Aces High Bulletin Board
General Forums => Aircraft and Vehicles => Topic started by: niklas on April 19, 2002, 03:27:15 PM
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ok now everyone will say is this guy crazy the G10 climbs like a rocket.
But lets compare:
109G10 7400lb 2000hp = 0.27hp / lb climbrate 4600ft/min
spit14 8460lb 2000hp = 0.23hp/ lb climbrate 4900ft/min
tempest 11400lb 2600hp = 0.22hp/lb climbrate 4600ft/min
though -by far - the G10 has the best power to weight ratio it climbs worse than a spit14 that has 800lb more weight. or equal to a tempest that has more power (i assumed A LOT of more power) and MUCH more weight.
sry that canīt be true. Why does the G10 climb so bad??
niklas
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I'm guessing it's the prop. Apparently Bf 109G did not have a constant speed prop.
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you start smoking the chiba again funked? are you saying they had a constant pitch propeller?
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Somebody posted a pilot report of flying the G-2 yesterday, and the pilot mentioned the plane did not have a constant speed prop.
Edit here it is: http://www.hitechcreations.com/forums/showthread.php?s=&threadid=51319
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Originally posted by funkedup
Somebody posted a pilot report of flying the G-2 yesterday, and the pilot mentioned the plane did not have a constant speed prop.
Edit here it is: http://www.hitechcreations.com/forums/showthread.php?s=&threadid=51319
End of the third paragraph:
"The engine is a Daimler-Benz DB605, driving a VDM variable pitch propeller which rotates clockwise when viewed from behind."
Variable Pitch = Constant Speed. Right?
Camo
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ehh funked i expected a better reply from someone like you. What you refer to seems to be the typical naiv RAF view of german technics. Yes, reducing manifold pressure also reduced RPM, but this wasnīt due to the lack of a constant speed unit, nono, this was the result of german single lever control unit technology hehe ;) But this isnīt the topic here.
FACT: Either RAF aircraft are overmodelled (they are, oh my god RAF has most overmodelled aircraft in the set imo, and they complain with spit and tempest over N1k or La-7 LOL) or G10 is undermodelled. Heck, even when i assume 1800hp the G10 should come close to a spit14. The 109 was always optimized for climb performance.
nik
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Oh Niklas, forgive me. I thought you were talking about real planes, not just making another FM whine.
I was just repeating what a man who flew the plane had to say. I'm sure he'd love to hear you talk about his "naiv" view. Hmm he's flying 109s and you're posting on a UBB, which one of you would be more qualified to discuss the prop system on the 109?
As for the performance of the Tempest and Spitfire XIV in AH, there is ample historical flight test data indicating that those aircraft perform correctly in the game. If you don't think the G-10 performance is right, then bring some flight test data to back it up. I'm sure HTC would love to see it.
And speaking of naive analyses...
You are considering only power and weight. Thrust and drag are important too. Have you ever seen a G-10 up close? It's skin is covered with bumps and protuberances and many unstreamlined features, which must cause a lot of drag compared to the quite smooth features of the Spitfire. Furthermore the G-10 has tiny wings for its weight, undoubtedly causing it to fly at a higher angle of attack than the Spitfire at best climb speed. Which means more induced drag. And we can't forget thrust. Could it be that the "naiv RAF" had a more efficient propellor design for low speed flight?
No, you ignore all of these possibilities and instead claim the programmers are in error. Ridiculous.
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Pfff whining. Of course i complain about the FM modelling, but this isnīt a whining like "tweak the N1k it is way too good and i got killed numerous times and this canīt be", nono, i brought up technical data, physics you know, and physics doesnīt lie.
hmm usually calling someone a whiner begins from posting nr. 20 on or so, you started at nr. 6 that is pretty early. Is this topic so unconvinient for you that you try to stop it this way right from the beginning? oh, i bet you KNOW that you have a nice present with climbrate of the spit14.....
nik
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historical RAF data lol even 1 year ago i showed that AH tempest is maybe 10-20mph too fast, and if you refer to AFDU spit14 test just compare critiacal altiutedes what may give you an imagination how much power was used in the AFDU trials
nik
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http://www.fourthfightergroup.com/eagles/spit14pt.html
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PS Sorry I edited that post. Read again, I added some new flames. :)
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Early in1944 the Air Fighting Development Unit at Duxford flew a Mk XIV Spitfire in a comparative trial against a captured Messerschmitt Bf109G. The 109G was the latest sub-type of this by-then veteran German fighter. The following are extracts from the official report.
SPITFIRE XIV VERSUS BF109G
Maximum Speed: The Spitfire XIV is 40 mph [64 km/hr] faster at all heights except near 16,000 feet
[4878 m] - where it is only 10 mph [16 km/hr] faster.
Maximum Climb: The same result - at 16,000 feet [4878 m] the two aircraft are virtually identical, otherwise the Spitfire XIV outclimbs the 109. The zoom climb is practically identical when the climb is made without the throttle open. Climbing at full throttle, the Spitfire XIV draws away from the 109 quite easily.
Dive: During the initial part of the dive, the 109 draws away slightly, but when a speed of 380 mph [611 km/hr] is reached the Spitfire XIV begins to gain on the 109.
Turning Circle: The Spitfire XIV easily out-turns the 109 in either direction.
Rate of Roll: The Spitfire XIV rolls much more quickly.
Conclusion: The Spitfire XIV is superior in every respect.
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OK I won't call it whining exactly. I apologizing for using the word "whine".
Let's call it "suggesting HTC are in error or dishonest without sufficient historical data or engineering analysis." This is more accurate.
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2 more things Niklas:
1. MW's Tempest site is down so I can't check those numbers. I remember there was some discussion of Tempest climb rate but I don't remember a problem with the speed.
2. Yes the AH Spit 14 critical altitudes do not match those in the A&AEE. The reason is because of a difference in supercharger gear ratio between the prototype and production engines. But the maximum speed and climb rate in AH is very similar to the A&AEE findings.
And even if we find that AH is different from the data on MW's website, does this mean HTC is wrong? Is it not possible that HTC have other sets of flight test data which we haven't seen. You have to remember that these guys have been doing this for a living since 1995. I'm pretty sure they have uncovered many documents that we amateurs don't know about.
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And I didn't get a nice present. I barely play AH these days. And when I do, it's scenarios. Tempest and Spit14 are never used in scenarios. And Tempest and Spit 14 are pretty much unusable in the MA due to perk pricing and gangbang-magnet-perk-icon. Whereas contemporary LW planes like G-10 and D-9 are unperked and have normal icons. So it's pretty clear who got the present here, and it's not me. :)
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Originally posted by funkedup
And I didn't get a nice present. I barely play AH these days. And when I do, it's scenarios. Tempest and Spit14 are never used in scenarios. And Tempest and Spit 14 are pretty much unusable in the MA due to perk pricing and gangbang-magnet-perk-icon. Whereas contemporary LW planes like G-10 and D-9 are unperked and have normal icons. So it's pretty clear who got the present here, and it's not me. :)
Your darn tootin. preach on.
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and if you refer to AFDU spit14 test just compare critiacal altiutedes what may give you an imagination how much power was used in the AFDU trials
Could you explain what you mean?
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Originally posted by Nashwan
Could you explain what you mean?
Probably not
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Dr. Zhivago,
I have the results of the tests you mention being conducted by the Air Fighter Development Squadron. They were published by William Green in his book "Augsburg Eagle." The aircraft being tested was a Bf 109G-6/U2 equipped with Rustsatz 2 (two underwing 20mm cannon gondolas) and the standard 30mm MK 108 cannon and two 13mm machine guns. Initial climb rate for the standard G-6 without Rustsatz 2 was 3,346 fpm at 7,000 lbs. normal loaded weight.
All other statistics are essentially correct. The report states that at the rated altitude of the 109G there was little to choose between the two fighters in climbing performance, but at all other altitudes the Spitfire possessed a marked advantage in rate of climb.
Tests against a Bf-109 G-10 would have come out somewhat differently. The G-10, from a standing start, could reach 20,000 feet in six minutes (Martin Caidin, "Me-109"). I don't know what the initial climb rate was for the G-10 upon leaving the ground but it must have been stupendous. The 109 G-2, with 1,474 hp for takeoff had an initial climb rate of 4,590 fpm. By comparison, the G-10 with DB 605DC engine had 2,000 hp available for take off.
Regards, Shuckins
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*Whistels*
Funked, gotto argree with you, climb performance in AH pretty much matches the numbers in book for all those 3 planes.
What doesn't SEEM (not sure how to calculate it) correct though is the climb angle, the 109's had a very steep climb angle but in AH all planes have more or less the same angle. IMO the 109 should have much steeper then it does, can anyone calculate it?
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Originally posted by funkedup
And I didn't get a nice present. I barely play AH these days. And when I do, it's scenarios. Tempest and Spit14 are never used in scenarios. And Tempest and Spit 14 are pretty much unusable in the MA due to perk pricing and gangbang-magnet-perk-icon. Whereas contemporary LW planes like G-10 and D-9 are unperked and have normal icons. So it's pretty clear who got the present here, and it's not me. :)
Isn't it funny how comments like these are perfectly allright as long as you are from the right camp. :)
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Hey that wasn't a whine, it was a counterwhine! :)
And you have to admit it is true.
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Good thing is that I don't have to admit anything cuz you can't point a gun at me over the pond. :D
Sooo...counterwhine isn't really a whine?? But what's the word whine doing there then? :)
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It's already been known for few years that german planes in AH are made by the lowest bidder, while british planes are made by the highest bidder.
also observed funny thing that people finds brit planes bit faster and finds german planes tad slower.
not other way around, if theres lacking/excess speeds.
then people will say "why do you complain of 10mph, thats nothing!"
so if ally plane is 10mph too fast and german planes 10mph too slow, it'll become 20mph difference.
mentioned things has also been found true with climb times.
okey.. go on, I were just reminding that nothing has changed.
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That's it Wmaker, I'm coming over the pond to get you. :)
It's OK, you can call me a whiner. I've called myself a whiner many times on this UBB. :)
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Niklas, you are excused now.
Fishu has come in with some major whining so I have no more energy for you.
Fishu is WW2Mod for GR ready yet? :)
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Originally posted by Fishu:
It's already been known for few years that german planes in AH are made by the lowest bidder, while british planes are made by the highest bidder.
Yeah, that's why we have the worst Spitfire Mk IX and worst Seafire ever whereas the Germans are saddled with the best Bf109G-10 and a MW50 equipped Fw190D-9. Those poor Germans.
The Bf109G-10 was also in AH from day one of it going live. The Bf109G-10 and the Fw190D-9 cost nary a point to fly, but if you want to fly the equivilent British aircraft you'd better have 60-70 perk points ready and be willing to be handicapped with a "gangbang" icon.
Yup, those Germans sure did get shafted.:rolleyes:
It should be noted that I do not feel in any way that the RAF fans have been shafted. We have one of the best planesets in the game, as do the German and American aircraft fans. I just don't think the German fans have anything to whine about, so I thought I'd poke some holes in their "woe is us" act.
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Originally posted by niklas
ok now everyone will say is this guy crazy the G10 climbs like a rocket.
But lets compare:
109G10 7400lb 2000hp = 0.27hp / lb climbrate 4600ft/min
spit14 8460lb 2000hp = 0.23hp/ lb climbrate 4900ft/min
tempest 11400lb 2600hp = 0.22hp/lb climbrate 4600ft/min
though -by far - the G10 has the best power to weight ratio it climbs worse than a spit14 that has 800lb more weight. or equal to a tempest that has more power (i assumed A LOT of more power) and MUCH more weight.
sry that canīt be true. Why does the G10 climb so bad??
niklas
How'd you get the ingame climb rates? Stopwatch?
I also think there is more to climb rate than just power to weight ratio. I'm a novice at this sort of thing, but I'd guess drag would play a significant role, and wing shape as well. Drag because it takes away from lift, essentially robbing the plane of horsepower, and wing shape because the Spitfire had a nice wing shape for low level performance. At least I think I read that somewhere lol.
Anyway, 109G-10 still climbs like a friggin rocket :).
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the wabbles used a bad paint layer wich made some drag too
:D
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Funckedup how can someone fly 109's anymore?
I thought there are no flyable 109's left.
If it's a converted 109 with a different engine then I doubt it has the original prop anymore either.
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It was a real 109g2 rebuilt to airworthy condition..Db605 and all.
then the stupid twits wrecked it....
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S! Funked
Are you gonna fly the CT when I run my late war setup with Spit XIV's perked at 2 points? :)
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Buzz I will whine about the perk price and fly in the MA in protest.
:D
j/k
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Originally posted by Nashwan
Could you explain what you mean?
Is it so hard to see? Just follow the link from funked and look at the charts from the links at the bottom. Compare them to the AH chart.
Why has an engine much less power in the High gear of the supercharger? Because it needs more power for more RPM. If you reduce the critical altitude you let the charger run with less RPM, and in case of the AFDU spit14 it means the spit was running with more power. Oh i just compared the speeds, the spit14 has the same speed like in the AFDU trials but a critical altitude for the 1st gear that is 5-7000ft higher - VERY FUNNY!
I modified those charts to demonstrate you the effect of the supercharger design. The blue line connects both critical altitudes. Now i draw a horizontal line from the AH critical altitudes, this gives me now the power with the new critical altitude. In case of the climbrate i can go down vertically (green line) or in case of the speed i draw a parallel line to the given curve.
(http://members.tripod.de/luftwaffe1/sonstiges/spit14climb.gif)
(http://members.tripod.de/luftwaffe1/sonstiges/spit14speed.gif)
Is my method 100% accurate? No, but very close. Is it better or worse for the spit? Actually better, because at low altitudes density changes much faster than in high altitudes. That means lowering your critical altitude from 5000 down to 2000 will give you more power than from 25000ft down to 22000ft.
You may also read the intro of the spitfire testing page, this gives you also some hints about the credibillity of the test
It is tycial for RAF tests of german equipment that in the case of the 109G - Spit comparison they doesnīt mention wing gondolas. In case of the 109E test they donīt mention engine or supercharger problems and so on. Always telling half the truth, what gives you of course a completly different view.
Anyway, the question is only to 30% why does the RAF planes climb so good, the question is to 70% why does the G10 climb so bad. Even G2 and G6 do ~4000ft/min, and the G10 is not much heavier but has a LOT more power. I always wondered myself but now the time has come to ask.
niklas
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"then the stupid twits wrecked it...."
Yeah and that stupid twit was Mark Hannah, who died in hospital later and him and his father has been one of the best promoters and restorers of WW2 aircraft...what a bunch of twits.
Daff
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Ouch baby.....ouch
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Ok back to the original subject.
Niklas your only looking at Horsepower to weight ratio. Like some other have said, don't forget drag as well.
But your forgetting once very important item.
Prop Efficency.
A good example is the F4U. The F4U-1(A) and the F4U-1D have essentially the same engine, and are close in many other physical characteristics, but the -1D climbs much better.
You have to transfer the power from the engine into acceleration, which is essentially the same as climb rate (ie excess power).
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The Spit XIV is that good. And the G10 is not a K4 which would reach 16K in about 3 minutes.
And the biggest changes between G10 and K4 - if i remember right - were small changes to make the K4 "cleaner" which is just reducing drag.
What we all should not forget is that roughly no operational planes in WW2 would match the numbers we have in AH.
There is an RAE report at the PRO (document # AVIA06-10393) that contains an examination on speed differences between data sheets (taken from the manufactures "production" machines) and real production plane performances on spitfires.
Production machines were slower in general even up to more than 25 mph. And this differt from machine to machine also.
So we in AH can atleast be glad that the planes we have perform like the performance charts on the AH page.
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vermillion:
A) in a climb drag is not as much the deciding factor as for topspeed. After all the Spit was not better, maybe even worse looking at drag. More surface area, worse cooler and so on.
B) More blades doesnīt necessarily increase your efficiency. In opposite, in a slower flight - climb - the disturbing effects of one blade on the other is maybe even more pronounced than in a fast one. The Diameter wasnīt larger too.
Oh, when someone thinks the 3-bladed prop of the 109 couldnīt handle 2000hp: The world record machine 209 (109R) had an engine with 2770PS and a 3 bladed propeller with ~3m diameter.....
niklas
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Originally posted by Daff
"then the stupid twits wrecked it...."
Yeah and that stupid twit was Mark Hannah, who died in hospital later and him and his father has been one of the best promoters and restorers of WW2 aircraft...what a bunch of twits.
Nope Daff, The accident that Mark Hanna died in involved OFMC's Hispano Buchon HA-1112-M1L G-BOML. NOT Black 6 which is an original Bf-109G-2.
Black 6 was wrecked by RAF officer, and yes, he was a twit.
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Niklas, at the start of the Spitfire page Funked linked to, they mention production aircraft would get a different ms supercharger gear ratio. That would explain the differences, and the fact that the AH Spit climbs worse at low level than the tested one.
I found these charts over at the All About Warfare forum, courtesy of Neil Sterling.
http://pub47.ezboard.com/fallboutwarfarefrm1.showMessage?topicID=777.topic
Perhaps the RAF made them up, too?
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I wanna Hornet.
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Hmm, I wonder where Ho Hun and Wells are. More viewpoints from the aeronautical angle would come in handy in this debate.
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Originally posted by Nashwan
Niklas, at the start of the Spitfire page Funked linked to, they mention production aircraft would get a different ms supercharger gear ratio. That would explain the differences, and the fact that the AH Spit climbs worse at low level than the tested one.
You donīt want to understand or what? The AH sptifire climbs too good, not too bad. Just look at the green lines in the charts.
Any further details avaiable for the charts of butch2kīs page? Aircraft description, weapon load, surface condition, speedcorrection and so on?
nik
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:D ALL WILL KILL SPITFIRES:D
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I modified those charts to demonstrate you the effect of the supercharger design. The blue line connects both critical altitudes. Now i draw a horizontal line from the AH critical altitudes, this gives me now the power with the new critical altitude. In case of the climbrate i can go down vertically (green line) or in case of the speed i draw a parallel line to the given curve.
That's the part I don't understand.
How does connecting the MS critical alt and the FS critical alt give you the power available to a differently geared MS at a different alt?
Regardless, you can look at the power charts yourself
Griffon 61 (with modified MS, by the look of it)
http://pub47.ezboard.com/fallboutwarfarefrm1.showMessage?topicID=754.topic
Lots of Russian figures, including a Spit XIV and what looks like an un-rammed Griffon
http://pub47.ezboard.com/fallboutwarfarefrm27.showMessage?topicID=282.topic
Any further details avaiable for the charts of butch2kīs page? Aircraft description, weapon load, surface condition, speedcorrection and so on?
If you compare the chart for the modified MS gear Spit XIV on Butch's page with the A&AEE figures, you will see they are almost exactly the same for FS gear.
That suggests the plane condition, ammo load etc are as set out in the A&AEE report.
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Viper that 109 HO pic looks very cool! Where did you get it?
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Nashwan, MS gear and FS gear are two independent choosen gear ratios.
In the FS gear (high altitude) the engine power output, though using same MAP and RPM, is lower than for the MS gear.
Letīs take an example, a fighter that should have the critical altitudes of the charger at 5000ft and 20000ft, for both 2.0 ata / +18lb. In 5000ft atmosphere pressure has dropped to 0.84kg/m^3, so you need a compression ratio of 2,38:1 to reach 2.0 ata. in 20000ft atmosphere pressure has dropped to 0.47, so you need a compression ratio of 4.25:1 to reach 2.0ata.
Logically you need more power in the FS gear due to your higher compression ratio. This is the main reason why your engine has less power avaiable to drive the propeller in the FS gear. The problem is that for charger with fixed gear ratios, you have only 1 altitude where your charger runs optimal. The speed of the charger is constant also in other altitudes as long as your engine rpm is constant, this means you compress in my example near ground the air with a ratio of 2,38 to 2,38ata, or in 10000ft you compress the air with a at.p. of 0.70 and 4.25:1 to ~3ata. Way too much.
Letīs assume the engine produces 2000hp in the MS gear at 5000ft, and 1500hp in the FS gear at 20000ft. Now you want to change the first gear in a way that you reach 2.0ata in 10000ft with it. How much power will you have in 10000ft then? Logically it will be somewhere between 2000hp and 1500hp. Now what i did was a simple linear interpolation between those 2 points.
Check this picture. I modified now the engine chart that was made for speed (it includes ram-effect). Here i went the opposite way from a real griffon to the AFDU griffon. Check first the bottom green line. It gives you the bhp near ground when you would use the FS gear at sealevel. Connecting the critical altitudes gives me again the maximum bhp avaiable for any cricitcal altitude. So when i choose only 5k, my bhp goes up to way over 2000hp.
(http://members.tripod.de/luftwaffe1/sonstiges/spit14power.gif)
now it shcould be clear.
about the other docs. They basically say that the spit14 could reach 4800-5000ft/min with only 1850hp near ground. This improves the power to weight ratio advanatage of the G10 even more. And the question becomes even more valid why the G10 climbs poorer.
niklas
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Hi Niklas,
I think you have a point with regard to the Me 109G-10's climb rate. Here's an extrapolation of the initial climb rate for the Me 109 types I did a while ago:
Basis:
Me 109F-1: 2728 kg, 1175 HP, climb rate 18.5 m/s
Extrapolation:
Me 109F-4: 2890 kg, 1350 HP, climb rate 20.9 m/s
Extrapolation, 10% drag added over Me 109F-1
Me 109G-2: 3100 kg, 1475 HP, climb rate 21.2 m/s
Extrapolation, 10% drag added over Me 109G-2:
Me 109G-6 (MW50): 3320 kg, 1800 HP, climb rate 24.8 m/s
Me 109K-4: 3362 kg, 2000 HP, climb rate 27.8 m/s
Drag is not a major factor in the climb due to the low speed, it requires about 280 HP for the Me 109F-1 and about 340 HP for the Me 109K-4 to overcome.
If for example I'd add another 10% of drag to the K-4 numbers to account for the G-10's poorer aerodynamics, that would still leave it with an initial climb rate of 27.3 m/s (compared to 27.8 m/s).
The calculated value of 27.8 m/s equals about 5500 fpm, which matches the published figures for the Me 109K-4 quite well, so I'm confident my calculations are good enough to give a coarse impression of the Me 109 variants' climb rates.
A climb rate of just 4600 fpm (23.4 m/s) seems a bit low for a 2000 HP Messerschmitt. That's even below my calculation for the 1800 HP Me 109G-6 with MW50 (24.8 m/s).
Regards,
Henning (HoHun)
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Originally posted by funkedup
Fishu is WW2Mod for GR ready yet? :)
at this rate.. never :I
Karnak,
well, at least they got their worst spit IX manufactured by highest bidder :)
thats the whole issue here, not who gets the best model, but whos models are best manufactured. :)
Ps. happen to remember the time when Spit IX was nearly a spacecraft?
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Originally posted by funkedup
You are considering only power and weight. Thrust and drag are important too. Have you ever seen a G-10 up close? It's skin is covered with bumps and protuberances and many unstreamlined features, which must cause a lot of drag compared to the quite smooth features of the Spitfire.
I agree that Spitfire is easily more drag-free design. I also agree with Ho Hun that at speeds between 300-200km/h drag is nearly a non-issue...we are VERY far from top speeds of these planes here.
According to my sourches (Daimler-Benz performance sheet) DB-605D with MW-50 could put out 2200hp at sea level.
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Originally posted by Daff
"then the stupid twits wrecked it...."
Yeah and that stupid twit was Mark Hannah, who died in hospital later and him and his father has been one of the best promoters and restorers of WW2 aircraft...what a bunch of twits.
Daff
Doenst matter who it was. It is stupid to fly a one of a kind historical treasure.
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Okay, wrote a long reply and the board lost it :(
Niklas, your method doesn't take eficiency into account.
FS gear on a Griffon turned the impeller with tip speeds faster than mach 1. Got to be less efficient.
According to your method, the Spit XIV with 1850hp at sea level is only 8 mph faster than the Spit LF IX, with 1500 hp at sea level.
23% power increase, 2.5% speed increase.
According to the tests you don't believe, that 23% power increase gives 8% speed increase, which seems closer to the mark.
Your method should also be applicable to the Spit LF and HF IX, as iirc the Merlin 66 and 70 differed only in supercharger gear ratio.
If you apply your method to the LF and HF, it doesn't work. Climb is out, and speed is wrong as well.
In fact, speed is quite close at medium altitudes, but gets increasingly worse the higher or lower you go, suggesting efficiency at the extremes is the problem.
Your method would also give the Spit XIV lower climb rates at low level than the Spit IX, only 4500 ft/min (the critical altitude in climb was just over 9,000ft, not the 8000ft you used.)
In fact, there is a difference between the Spit prototype tests and the later ones, the raising of critical alt has made a difference, just nowhere near as large as you are suggesting.
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Sorry, just had a look at the speed approximation again.
(http://members.tripod.de/luftwaffe1/sonstiges/spit14speed.gif)
You hve used the wrong critical alt for the Spit, the later chrts show just over 12,000ft. I know you are calculating for AH, but just for a minute apply it to real life.
Your figures suggest that if critical alt is raised to 12,000ft, speed at sea level will be down to around 335mph. Is that correct?
If so, it implies raising critical alt by 7000ft decreases speed at sea level by nearly 30mph.
The Spit LF IX had a critical alt of 10,800, the HF of 15,400, a difference of 4,600. That decreased speed by about 5 mph.
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Going by the manifold pressure gauge, it looks like WEP is giving you only 1.8 atm which implies the 605DB engine (1800 hp) for the 109G10.
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Do you mean with impeller the supercharger? Why should it be less efficient? What are the gear ratios? I assume 1:10 and 1:15 or so. I bet even for the MS gear the tips run with more than Mach1. But this is not a propeller, the airflow is from the inside to the outside and not vertical like for a propeller, so it isnīt so critical. In opposite, for a compression this is maybe an advantage. Even the LF test mentions : "These modifications had the effect of raising the supercharger top speed, thus improving the efficiency".
The LF version had a Merlin66 engine that produced with +18ata 1700hp. The report mentions some improvments, so maybe power output was even higher. Gun ports were sealed. Maybe the cooler were also smaller than for the spit14? Maybe the lighter and more compact Merlin didnīt need as much balance from the elevator (less deflection), resulting in a bit less drag? And more than 1300lb less weight (~7100lb, from the graph image) has generally also a minor influence. Anyway, let it be 350mph for the spit14 - no problem here from my side.
Climbrate: The spit14 has at low altitudes roughly 200hp more power. Actually a bit less. This is 12% more power (actually only 11.7) compared to 1700hp, but it has 13% more weight. So power to weight ratio got worse. No contradiction to my theory, in opposite, climbrates up to 5000ft/min of the spit14 becomes more and more questionable for a "normal" spit14 and favour my theorie that those tests were done with griffons doing 2200hp or even more.
That the spit LF equipped with a lower MF gear ratio (spit 354) was SLOWER than the Merlin66 equipped spit surprised even the engineers obviously:
".It is a matter of interest that at sea level, Spitfire BS.354 with the RM-9SM engine, although nominally develping 50 B.H.P. more power than the Merlin 66 engines BS.543, is 7 m.p.h. slower, indicating either that the nominal powers were not realized and/or that there was a considerable difference between the drags of the two aircraft."
BUT this DOES confirm my theory. Why does the RM-9SM produce 50hp more power ehh? lower critical altiutde my friend ;) This does exactly confirm my theory!
niklas
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Originally posted by wells
Going by the manifold pressure gauge, it looks like WEP is giving you only 1.8 atm which implies the 605DB engine (1800 hp) for the 109G10.
According to this profile drawing AH's G-10 has (or should have) DB-605DCM engine.
(http://www.hitechcreations.com/forums/attachment.php?s=&postid=433723)
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By Doc 109, May 2001
The DB605AS was born around the concept that it could be possible to recycle the existing DB605A into a high altitude engine, comparable to the new DB605D. The DB605D needed 2 bulges on the forward edge of the underside cowl due to the slightly different profile of the valve covers. Otherwise, the engine had similar dimensions to the A version. The AS and D versions had virtually identical performance ratings as well. This may look weird from our point of view, but there is a rational explanation.
The DB605D was intended to be the sole high altitude version of the DB605 but the program encountered huge delays. The situation deteriorated to the point that in the spring of 1943, the increasingly desperate Luftwaffe ordered an interim solution to be found. That solution was to install the DB603 supercharger on the DB605A. Performances were almost identical to the coming DB605D. In fact, when the DB605D entered production, the DB605AS continued to be produced as well since it allowed for the recycling of existing engines.
After autumn 1944, DB605D engines were only delivered to factories producing new 109G-10s and K-4s, while the DB605AS engines were delivered exclusively to the workshop and repair centers, which explains why its possible to see a G-10 with a DB605AS- it would have been installed during a repair. The DB605AS was not suitable for the K-4, however, since this aircraft relying upon the engine compressor to supply pneumatic pressure for the centerline MK108 cannon (The G-10 still used bottles).
So, from a visual perspective, the general rule is no DB605D= no bulges= no enlarged oil cooler.
However: A few of the last DB605AS produced (installed on G-14/AS) got the new valve covers from the D version therefore needing the bulges.
To add even more confusion, some G-14/AS got the lower cowl with bulges in order to use the enlarged oil cooler from the K-4/G-10 versions.
Thus, to reiterate: GENERALLY, there were no bulges on the AS version, but as we've seen, there are exceptions.
Finally, let's not forget the Erla produced G-10 which had a totally new enlarged underside cowl which makes the plane look like a G-14/AS...
Maybe read this too (http://109lair.hobbyvista.com/home.html)
The 109g10 we have is said to be have a DB605D engine. It shouldn't have the bulges or oversized oil cooler if so drag would ne less then a g14 or g6/as.
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Niklas,
The speed of the supercharger in the DB 605 series was variable just in the gven range (typically between about 7-10:1) . For example at 1,42ata the DB 605 utilized variable speed between 2-5,7km, outside these altitudes it was a fixed speed system. It should be also noted that hydraulic coupling allways wastes some energy (2-3%).
gripen
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What are the gear ratios? I assume 1:10 and 1:15 or so.
I remeber seeing 5.5 and 8, but I can't remeber where.
The LF version had a Merlin66 engine that produced with +18ata 1700hp. The report mentions some improvments, so maybe power output was even higher.
I have seen peak output quoted for the Merlin 66 as 1670hp or 1760hp. That looks like a misunderstanding to me, but could be a genuine power difference.
Anyway, let it be 350mph for the spit14 - no problem here from my side.
It's not a question of let it be. You can't come up with a way of working out performance, and when the result is too low say ok I'll agree it's more, and expect your model to be accurate. If your model shows 335, and you don't want to accept that, your model doesn't work properly.
Your calculations show 335mph at sea level for a Spit XIV with FTH of 12,200ft in MS gear. That is the same speed as a Spit LF IX. That suggests to me an error in your method.
Again, a change of 4,600ft in FTH in the Merlin produced a speed difference of 5 - 7mph.
Your figures show a difference in FTH of 7000ft in the Griffon producing a speed difference of 28 mph. I find that impossible to believe.
Climbrate: The spit14 has at low altitudes roughly 200hp more power. Actually a bit less. This is 12% more power (actually only 11.7) compared to 1700hp, but it has 13% more weight. So power to weight ratio got worse. No contradiction to my theory, in opposite, climbrates up to 5000ft/min of the spit14 becomes more and more questionable for a "normal" spit14 and favour my theorie that those tests were done with griffons doing 2200hp or even more.
The LF IX had around 1700hp at 7,000ft (FTH). ROC was 4700ft/min. Weight 7485lbs.
The XIV had 2000hp at 9000ft. ROC was nearly the same. Weight was 8400lbs.
That gives the Spit XIV 4.2lbs/hp, and the LF IX 4.25lbs/hp if you assume 1760, 4.48lbs/hp if you assume 1670hp.
Those figures seem in line to me.
That the spit LF equipped with a lower MF gear ratio (spit 354) was SLOWER than the Merlin66 equipped spit surprised even the engineers obviously:
".It is a matter of interest that at sea level, Spitfire BS.354 with the RM-9SM engine, although nominally develping 50 B.H.P. more power than the Merlin 66 engines BS.543, is 7 m.p.h. slower, indicating either that the nominal powers were not realized and/or that there was a considerable difference between the drags of the two aircraft."
BUT this DOES confirm my theory. Why does the RM-9SM produce 50hp more power ehh? lower critical altiutde my friend This does exactly confirm my theory!
This is getting bizarre.
A plane that is supposed to have more power, but doesn't seem to have more power, confirms your theory?
If BS 354's odd performance was down to drag, presumably climb would not be so affected. However, it was badly affected with BS354 trailing well behind in climb rates as well.
In fact, BS354 seemed to have similar climb performance in FS gear, indicating it had less power in MS gear, not more.
In other words, their theory being wrong confirms your wrong theory as well?
, climbrates up to 5000ft/min of the spit14 becomes more and more questionable for a "normal" spit14 and favour my theorie that those tests were done with griffons doing 2200hp or even more.
Okay, now I have real problems.
Why would they try to hide the fact if the Griffon was producing 2200hp or more?
If a Griffon could be run at 2200hp at 18lbs boost, I would think they would acknowledge that fact, and make them all that way.
Secondly, a Spit LF IX doing 4700ft/min has a lbs/hp ratio of 4.48 to 1.
A Spit XIV with 2200hp would have a lbs/hp ratio of 3.81 to 1.
A Spit XIV with 2050hp (usuall quoted figure) would have a ratio of 4.09.
In other words, assuming it wasn't all some giant conspiracy, and using the figures published, the Spit XIV should be much better than the IX anyway.
The other point is that a 2200hp Spit should go faster than 363 at sea level.
If a 1500hp Spit IX can do 335, you think that 46% more power would only get you 8.4% more speed?
Which Spit figures do you disbelieve, and which do you believe?
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thrust decreases linearly with airspeed. drag increases quadratically (zero lift drag) and it dominates at near vmax speeds so as a very rough approximation you can say that a x increase in power should give a x^.3333 increase in speed (as i said very rough because ignores prop eff. but if you resign the prop you shoudl be able to achieve comparable efficiecies). It also ignores the larger induced drag present even at high speeds due to the greater weight.
hence a 46% increase in power should yield about a 13.4% increase in speed ie i would expect a 2200 hp spit to be able to optimistically reach nearly 380 on the deck.
if the griff could truly produce 2050 on the deck you would expect around the ballpark of 366. but like I said thhis cube root rule is very optimistic.
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at speeds between 300-200km/h drag is nearly a non-issue.
Induced drag is quite significant in that speed range.
Only about 60% of the engine's power goes towards increasing energy (climbing) at best climb speed. Where is the other 40% of the power going? Prop inefficiency and drag. You can't just ignore 40% of the power requirement and expect to answer why one plane outperforms the other. At least not if you are actually interested in answering the question objectively...
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Sorry all, but I'm still trying to understand this.
(http://members.tripod.de/luftwaffe1/sonstiges/spit14power.gif)
I've looked at this again, and I can see I was wrong in thinking you meant 2200 hp at sea level. Looks like you are suggesting 2130 at sea level.
Apart from the performance differences you'd expect, this chart seems wrong to me.
You have taken the power beyond what a Griffon could do at 21lbs boost. My understanding of what you are saying is that gearing the supercharger to produce the same boost at a higher altitude means more power is used for the supercharger at all altitudes, because it has to spin faster. (not sure about above rated alt, but we are talking below anyway)
I accept that, I just don't think it's as large a power loss as you think.
This chart is instructive, because it shows you think raising the FTH meant the supercharger consumed an EXTRA 300 hp, over and above what the supercharger was consuming in the Griffon rated for the lower altitude.
Taking your chart to extremes, and calculating a supercharger rated for 0 ft, we see that the Griffon rated for 12,000ft is using 500hp more to drive the supercharger than one rated for 0 feet.
The zero feet rated supercharger would have to add 18lbs per square inch pressure, the 12,000ft superchrager would have to add 22lbs pressure. The one rated at 0ft would have to compress at approx 1.8 to 1, the one rated at 12,000ft at 3.2 to 1.
I'm getting confused here, but if you assume double the power to raise boost to 18lbs at 12,000ft that it would take at 0 ft , and it takes 500 hp MORE for the 12,000 ft rated engine, that implies the 12,000ft rated engine is using 1000hp for it's supercharger, in MS gear.
Your chart also implies the prototype with the lower FTH would be faster all the way up to 7000ft than a Spitfire XIV running 21lbs boost with 150 octane fuel.
Considering 150 octane was first authorised for V-1 chasing, which took place below these altitudes, and that great effort as put into making high octane fuels, experiments with NO2 etc, it seems a waste when all they would need to do is change the gear ratio in the supercharger.
Changing a gear ratio doesn't sound like a huge amount of effort to me, not when compared with the efforts actually used to fight the V-1s.
A chart showing speed increase that could be obtained by using high octane fuel at 3000ft shows the Spit XIV at 372 mph at 3K at 18lb boost, which is the same as the revised production figures, slower than the prototype figures (about 380 at 3K)
With 21lbs boost, it shows speed increasing to 393, with 25lbs boost 410mph.
Your horsepower extrapolations show lowering the gear ratio would mean horsepower mid way between the 21lb and 25lb figures, for a speed of around 400 mph.
As it was, early Spit XIVs were limited to 21lbs because of bearing weaknesses, so just by changing gear ratios the Spit XIV could have been faster chasing V-1s than it as running on 150 octane fuel.
Sounds wrong to me.
When there was an effort to make a Spit V faster at sea level, they cropped the supercharger impeller to reduce the ammount of power used by the supercharger. Why bother if changing the gear ratio would do the same?
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Originally posted by Wmaker
According to this profile drawing AH's G-10 has (or should have) DB-605DCM engine.
(http://www.hitechcreations.com/forums/attachment.php?s=&postid=433723)
It might be, but the manifold pressure is still only 1.8 atm for 1800 hp. If it were 2000 hp, you should be seeing 1.98 atm (59" Hg) on the gauge and the climb rate would be better. :)
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Nashwan,
Some supercharger gear ratios of the RR engines:
Merlin 61: 6,39 and 8,03
Merlin 66: 5,79 and 7,06
V-1650-3: 6,39 and 8,095
V-1650-7: 5,80 and 7,35
Griffon VI: 9,0 and 11,07
Griffon 65: 5,84 and 7,58
gripen
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Hi Funked,
>Only about 60% of the engine's power goes towards increasing energy (climbing) at best climb speed.
Could you elaborate on how you arrived at that number? By my own calculations, the Me 109K-4 expends about 83.5% of its engine power for climbing.
Regards,
Henning (HoHun)
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Spanish
Pido perdon por esta mala traduccion al ingles, pero uso "altavista translator" y posiblemente no esten mis palabras lo suficientemente claras para los angloparlantes, Si alguien puede hacer una mejor traduccion, por favor, haganlo. Gracias.
Todos Los datos que se escriben en estos post son datos procedentes de pruebas de la RAF o USAF, y como muy bien dice Niklas en ellos se omiten muchas cosas, estoy seguro que intencionadamente por motivos propagandisticos. Mi pregunta es:
No hay esas mismas pruebas comparativas entre Spitfire, P51 versus 109 o 190 en los archivos capturados de la LW?
Si existiesen, podrian ustedes hacerlas publicas?
English
I request pardon by this bad translation to ingles, but translator "altavista" use and the sufficiently clear thing for the English-speakers possibly do not esten my words, If somebody can make one better translation, please. Thanks.
All the data that are written in these post are data coming from tests of RAF or USAF, and as Niklas in them says very well omit many things, I am sure that deliberately by propagand reasons. My question is: There is those same comparative tests between Spitfire, no P51 versus 109 or 190 in the captured archives of the LW
Supongo
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Woo-hoo, what a lot of data. Thanks everybody, I collect that kind of stuff
;)
It seems that the best way to get the world's best data is to let out a thesis if this kind in the AH forum.
Now we have a lot of numbers here, I do not want to add a lot more. I'll keep to what real ww2 Pilots said.
Firstly, The Spitfire and the 109 were practically on par in climb rate pr. Hp, the Spitfire winning by a slight margin if anything.
Example: Spitfire I would be able to hang on a 109E's tail, except for the Steep angle of the 109E. I guess that would mean the 109 generally climbs steeper at a slower speed.
(various sources)
Spitfire Vb would catch a 109F in a prolonged climbing race.
(T.E.Jonsson)
Spitfire XIV would not need to worry against anything. In Spitfire XIV pilots would even allow themselves to be bounced, just to get the german plane to the fight, once they were at the same altitude, the german had no chance of escape
(J.Johnsson, R.H.Harries)
Looking at the aircraft this looks logical. The Spitfire simply had a more efficient wing, and most often a lower wing loading too. Increased Hp would just exaggerate the difference between these two aircraft.
Now there was quite some data about manifold pressure, WEP, constant speed props etc etc.
There was a reason why the spit XIV had more propeller blades than earlier versions. With more power, you need some way of turning it into torque, and lengthening the prop was out of the question because of the bladetips breaking the sound barrier. Thus more blades.
Looking at the 109 prop I am a wee bit confused, - how did they turn 2000 Hp properly into torque through THAT?
WEP is another abstract factor. With only 5 minutes of WEP recommended, the RR engines were known to be able to take up to 30 minutes without damage. I do not know about the DB, but I do know that for some reason it would wear much quicker than the RR, losing power earlier in its lifetime than the RR. That however applies to real life and not our sim.
And finally, when it comes to variable pitch/constant speed, I think I am right in saying that at the time, the Germans were not ahead (any more? of the Allies.
Well, enough now, keep on flaming
:D
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Originally posted by Nashwan
Your figures suggest that if critical alt is raised to 12,000ft, speed at sea level will be down to around 335mph. Is that correct?
No. First i used indeed AH altituted. Furhtermore you can see that the gradient down from the 2nd gear is steeper. If i use a mean gradient speed wonīt become so bad.
You donīt want to understand obviously. Those lines drawn in 20seconds are not 100% correct and i donīt want to say the spit performed exactly this way. I just want to give you an imagination about the effect. You better look at the climbrates, which depend much more directly on power instead of speed.
Those other docs with 12k alt are nice, but it is noteworth that
A) no further detail are available compared to the data from mwīs pages. Just lines that could be also calculations, and which can be drawn by every child in 20seconds.
B) the date in the bottom right corner says July 46. Those charts were made over 1 year later then the end of the war, or 2 years later then the introduction of the Spit14 in the RAF. You have to decide yourself whether you consider those charts, maybe from spits produced under civil circumstances instead of wartime (what also could mean not in armed mode), are representative for a ī44 spit14.
I have seen peak output quoted for the Merlin 66 as 1670hp or 1760hp. That looks like a misunderstanding to me, but could be a genuine power difference.
I assume that one power output is for sealevel, the other for the critical altitude of the 1st gear. The power outputs for the RR engines are very often given for the critical altitude of the 1st gear, what is usually higher than sealevel output. The griffon is given with 2050hp, but at sealevel the output was only 1850hp-1900hp. This way the power output looks better, german engines are usually given with sealevl output AND sometimes, especially in case of the 801 with the reduced poweroutput due to rameffects. (static thrust 1800PS, dynamic 1730PS or 1700hp).
A plane that is supposed to have more power, but doesn't seem to have more power, confirms your theory?
The first time i donīt understand. The spit is supposed to have more power, but look what the engineers said, they assumed drag problems or unknown loss factors. So practical results vary from theoretical predictions, like so often, but the important fact is that the R4.. engine is supposed to have 50hp more with a reduced critical altitude of the 1st. gear.
Your doubts about the influence of the gear ratio on power are valid. The differences look also very large for me. But i only can repeat those charts from me were basically made to demonstrate you the effect, and not to make an exact calculation.
Originally posted by Wells
Going by the manifold pressure gauge, it looks like WEP is giving you only 1.8 atm which implies the 605DB engine (1800 hp) for the 109G10.
Yes, but i donīt believe those gauges. The tempest gauge goes up to only +9lb, does this mean it climbs 4600ft/min with only 2100hp? Well, even when it should be +11lb and 2300hp, when 4600ft/min are modelled for such an average powerloading, then iīm not surprised why the Tempest flies like it does fly. Even 2600hp canīt explain imo the climbrate.
But even with 1800hp near ground, the G10 has a powerloading of 0.243hp/lb, the spit14 with 1850hp near ground 0.219hp/lb. This means the powerloading of the G10 is still 11% (!!!) better. And it climbs 300ft/min worse???
Originally posted by Funked
Induced drag is quite significant in that speed range.
The steeper you climb the less is the influence of induced drag, because your wing must produce less lift. The aircraft with the higher wingloading becomes superior, less wingarea, less drag. This changes in high altitudes, where usually low wingloadings can keep the advantage.
Originally posted by Agnus
The Spitfire simply had a more efficient wing
I really wondered myself when someone brings up the unique "the elliptical wing explains everything" argument. Actually the wing of the 109 was much superior. The wing of the spit can described by only 2 words: wing area. Lot of wing area, thatīs all. No slats, cannons and guns in the wing, only one setting for flaps.. actually a very primitive wing. Nevertheless it can achieve with a very gentle slow speed handling the lift coefficients of a 109 that uses slats and has no disturbing weapons in the wing(same for Tempest, Typhoon), but i already said that i consider RAF planes the most overmodelled ones in the set. The naca test says the spit had a surpisingly low CL btw, and this was a wing with 8*30. Installing the large cannons booms reduced cl by another 2-5% for sure!
What remains for the 109 is the poorer arment of only one central mounted cannon....and even dispersion is very close to that of a spit where the cannons are mounted far outside in a rather "soft" environment (wing)... ahh i better stop...
nik
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OK just one observation to make regarding lift and drag, the higher loaded and smaller surface area wing on the 109, to produce an equal amount of lift to the spits would have to be at a greater AoA and would generate higher drag.
Your argument that drag is really small at slow speeds does not appear to consider the higher drag caused by the wing flying at a greater AoA.
Now i have nothing like the aeronautical knowledge of some of the guys who could answer this, but it seems logical to assume at slower speeds the drag caused by the larger surface area of a wing would have less of an impact than the drag caused by a wing having to fly at a higher AoA.
Anyway flame away if you wish or correct me but saying "i dont believe it" aint good enough.
And you cannot put me into either camp as i rarely fly both there just too hard for me :)
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Hi Cavalier,
>Your argument that drag is really small at slow speeds does not appear to consider the higher drag caused by the wing flying at a greater AoA.
The point is not how the drag between two aircraft compares, but that it is very small compared to the power available for lifting the aircraft. Drag differences can't explain large climb rate differences.
Let's have a look at the Me 109K-4. It climbs at about 5500 fpm - as you can tell from climb rate and aircraft weight, this is equivalent to 1250 HP just lifting the aircraft. Assuming a propeller efficiency of 75%, the Me 109K-4 has only 1500 HP available. Accordingly, only 250 HP are left for overcoming the drag.
If you now add a ridiculous amount of extra drag, like +50%, you'd have 375 HP lost to drag, and 1175 HP left for climbing. This would still leave the Me 109K-4 with a climb rate of 4900 fpm.
This is still more than the 4600 fpm that Naudet quoted.
Wells' observation that the Me 109G-10 according to its instruments runs only at 1.8 ata, which would suggest just 1800 HP power, leaves us with similar numbers:
1800 HP total, 1350 HP available, 250 HP spent on drag, 1100 HP left for a climb of 4800 fpm.
The conclusion: There's reason to speculate that the Me 109G-10 in Aces High is equipped with an engine of 1800 HP (or less).
Regards,
Henning (HoHun)
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Prop designs for climb or speed, the never ending problem gets much worse with more HP.
Just curious anyone every think what happens to thrust when the prop airfoil stalls? And hence why the padle blade was devloped?
Or about such simple things as the effect of the prop to eng gear ratio?
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Hohun here's an example, Fw 190A-5.
h_dot (rate of climb) = 3900 ft/min = 65 ft/s
W (weight) = 8600 lb
Rate of energy change (assuming constant TAS climb) = W * h_dot = 8600 * 65 = 559000 lb-ft/s = 1016 hp.
(conversion factor is 550 lb-ft/s per hp)
P (engine shaft power) = 1700 hp
W * h_dot / P = 1016 / 1700 = 0.598 = 60%
This is the fraction of engine shaft power which is used to increase the energy of the airplane at best climb speed.
WWII fighters tend to fall between 55% and 65% in my experience.
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Has anyone actually seen a G10 prop? It only has three blades but they are very very wide. Much wider than the 5 blades on the Spitfire XIV. Every succesive 109 model introduced wider blades to harness increasing power with the G10 and K4 having
enourmous paddle blades.
Look this certainly wouldnt be the first time AH had a FM performance error, maybe we just found a new one. Certainly this is a reasonable discussion using facts.
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Ho-Hun - I just read through the rest of your posts. The difference between your result and my result was the power figure. I'm using shaft power and you were using power available (shaft power times prop efficiency). Both of our results are valid, they are just answering different questions.
My point:
Niklas' rudimentary power/weight analysis did not include drag or prop efficiency as a possible reason for the performance variations between aircraft.
But it's clear that about 40% of the engine's power is wasted by the prop and drag. Obviously a variation in prop efficiency or drag could explain the performance variation.
But Niklas didn't seem to want to acknowledge this fact. Probably because it doesn't agree with his theory about incompetence and dishonesty by HTC and various Allied aeronautical agencies.
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As far as the relative importance of induced drag and zero-lift drag: Best climb rates for a prop fighter occur at a quite low airspeed, below the minimum drag speed. This is in the regime where induced drag becomes more significant than zero lift drag.
As far as climb angle: For non-maneuvering constant speed flight, climb angles for WW2 prop fighters are quite shallow at best sustained climb conditions. The angle is only about 15 degrees, which means only about a 4-6% lift reductions due to climb angle.
Induced drag is still going to be the dominant source of drag on the aircraft.
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Originally posted by funkedup
Induced drag is quite significant in that speed range.
Only about 60% of the engine's power goes towards increasing energy (climbing) at best climb speed. Where is the other 40% of the power going? Prop inefficiency and drag. You can't just ignore 40% of the power requirement and expect to answer why one plane outperforms the other. At least not if you are actually interested in answering the question objectively...
'
My comment about the drag came from reading about earlier 109s and how the lower engine power/top speeds "allowed" them to be un-aerodynamic until the E-series. DB 601A had enough power to bring 109E into speeds which encouraged the re-design of the cowlings to the F-series. Always wondered this a bit myself since more aerodynamic car goes faster than the not-so-aerodynamic and the speeds are still far from 310mph for example. :) So right now I agree that drag is a factor. That's one of the reasons why climb curves of these planes don't have a their peak at the sea level where the air is the most dense.
Funked, you are yet to hear an FM-whine from me...I'm pretty sure you never will. Search this board and try to find a single whine by me...you can't find one. I'm not going to try to convince you since I'm pretty sure you won't believe me on this but I'm really trying remain objective on this kind of stuff since love aircraft (especially WWII aircraft) in general. I find "my plane is better than yours-stuff" ridiculous and childish. You know, when I was a kid (ok well, smaller kid :D) my favourite fighter plane was P-40. I just loved the way it looked...still do. :) In short I love to discuss this kind of stuff I just hope people could leave their agendas and biases to the door.
So back to the G-10.
I'm assuming AH's G-10 has DB-605DCM engine because of the profile drawing (it's has the same markings as the one in AH) and because of its top speed (440-445mph according to the speed gauge). Depending on source its out put is listed between 2000-2200hp.
Here's comparision between G-2 and G-10 in AH:
G-2: power/weight: 0.216 hp/lbs. climb on the deck: about 4100ft/min (AH chart)
G-10: power/weight: 0.270 hp/lbs. climb on the deck: about 4600ft/min (AH chart)
Point of this comparision is that AH's G-2 climb chart is fairly close to what I have about real G-2's climb test. And even though G-10 produces more drag than G-2 the difference very small compared to the difference between G-10 and Spitfire. Prop between G-10 and G-2 is also very similar...G-10 has broader blades because of the added power.
So, 25% increase in power loading gives 12% (500ft/min) increase in climb rate. I dunno maybe so...
For the record, I'm very happy with the G-10 as it is. If something is wrong I hope it will get fixed...I doubt it tough...G-10 has been in the game since the beginning I think pyro would have allready changed it if something was off.
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Originally posted by LLv34_Camouflage
End of the third paragraph:
"The engine is a Daimler-Benz DB605, driving a VDM variable pitch propeller which rotates clockwise when viewed from behind."
Variable Pitch = Constant Speed. Right?
Camo
Variable pitch does not necessarily mean constant speed. There have been many propellers that had a manual (be it electric or hydraulic) means of varying the pitch, but were not constant speed props.
I believe that the VDM propeller had several different pitch settings, but was not constant speed.
My regards,
Widewing
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love to discuss this kind of stuff I just hope people could leave their agendas and biases to the door.
Amen Wmaker.
Here's what I think about G-10. This is my best guess:
HTC probably have some German flight test data showing the performance we have in AH.
The lb/hp stuff comparison with earlier 109G doesn't work out because the G-10 has too much motor for the prop. Or the actual power ratings of the plane tested are not what everybody thinks.
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Originally posted by funkedup
The lb/hp stuff comparison with earlier 109G doesn't work out because the G-10 has too much motor for the prop. Or the actual power ratings of the plane tested are not what everybody thinks.
Wouldn't it be VERY bad engineering to design bigger engine (more cubic inches) with more power...install into an airframe with allready high wing loading and not to have a prop to take advantage of the added power? I think G-10 had prop with broader blades for a reason.
Originally posted by funkedup
Amen Wmaker.
That involves you too Funked!! ;) :D
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Hi Funked,
>Induced drag is still going to be the dominant source of drag on the aircraft.
Climb rate is dominated by the power to weight ratio.
As I demonstrated above, you can increase drag by 50% and see your climb rate drop by just 12% for the Me 109K-4.
Regards,
Henning (HoHun)
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BTW if you look at the HTC chart for the G-10 and carefully measure the scale of the pixels, the peak climb rate is 4786 fpm.
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Hohun:
Climb rate is dominated by the power to weight ratio.
Obviously.
But that is not equivalent to "Climb rate is solely a function of power to weight ratio."
As I demonstrated above, you can increase drag by 50% and see your climb rate drop by just 12% for the Me 109K-4.
I didn't check all of your calcs but that sounds about right.
But the whole point of this thread is small variations in climb rate. Variations on the order of 10-15%. A variation of "just 12%" is exactly what this thread is all about. The difference between the AH G-10 (4786 fpm) and a nice fat figure like 5300 fpm is "only" 11%.
A little parasite drag here, a little induced drag here, a little prop efficiency here, and you can fully explain the variations that Niklas pointed out. No need to accuse RAF or HTC of error or dishonesty.
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Hmmm 1800 hp theory is interesting. I don't know much about different DB605 variants.
Seems like 1800 hp would explain the 4786 fpm climb rate.
What are the power ratings for G-2 and G-6? Using the cubic drag power approximation, can somebody work out how much speed increase we could expect with 1800 hp in those airframes?
E.g. Bf 109G-2
S/L ~340 mph (HTC chart), 1500 hp (HP figure I'm making up, don't know actual rating)
Increase to 1800 hp would give approximately 340 * (1800/1500)^(1/3) = 361 mph.
361 is pretty dang close to the HTC chart for the G-10.
So if my G-2 HP guess is correct, this seems to back up Wells boost argument and Ho-Hun's climb argument for an 1800 HP G-10 in AH.
If it's only 1800 hp then this points even more strongly to the K-4 being a good perk addition to the LW plane set.
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Prop designs for climb or speed, the never ending problem gets much worse with more HP.
True hitech. What do you think, was the tempest designed for speed or climb? Was the 109 in itīs lifetime well known also for climbrate or only for topspeed?
Actually the germans were the first who recognized that a prop designed for climb improves very much climbrate with a little loss of speed. If it helps you, a german prop test i have says the efficiency tops out for a 109K at 135m/s near ground (~490km/h), raising to ~150m/s at higher altititudes. This is imo not a design for topspeed only.
Just curious anyone every think what happens to thrust when the prop airfoil stalls? And hence why the padle blade was devloped?
ok and who developed paddle blades first? Again, search for pictures of the 109R /209 world record machine, it was able to handle 2770PS with a ~3m 3-blade propeller.
I donīt think that someone would have installed a power system that couldnīt be used because the prop was not suitable. That doesnīt make sense.
The decision to take a 5-bladed prop for the spit14 may have had other reasons. The longer nose of the Griffon made the space between prop and ground smaller during takeoff and landings, so they were forced to reduce diameter. Furthermore - not sure here - a 4-bladed one may cause oscillations during sharp manoevering. At least a symmetrical 2-bladed one causes torque moments during manoevering, the assymetrical 3-bladed one not, and maybe those effects are back for a symmetrical 4-bladed one. So "maybe" this were also reasons to switch over to a smaller assymetrical 5-bladed propeller. It was also clear that the Griffon could be soon boosted to much more than 2000hp, so maybe it was a decission for the future too.
Or about such simple things as the effect of the prop to eng gear ratio?
basically a question of altitude. You simulate obviously not the D engine with the bigger 603 charger but the first 1550ps basis variant, so the ratio should be the normal 1:1.625. Only for the true high altitude variants the ratio was changed to stay away from high prop tip mach numbers.
Actually the propeller of the spit14 runs with lower rpm, so especially near ground the propeller of the G10 should have the advantage.
btw should you simulate a 2000ps G10 then the power to weight advantage near ground compared to a spit14 is more than 20%.
niklas
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Just a short sidenote on Supongos request.
Yes there are performance tests from the LW containing data on allied birds.
I saw them today.
There publication is limited and i can't afford to buy them. Also you get no allowance to publish them once you have them.
But you can find them in Freiburg Archive in Germany.
And if we would ever build a sim just around those numbers, you would hear the allied cries up to the moon.
Its just a completely wrong concept to trust allied data sheets more than the original data sheets from the manufactures.
Niklas&HoHun, if you are interested were you can get original factory data on the 109er email me to LNhome@gmx.net. I will give you the email of the guy in germany that has all this documents in his private archive (roughly 16,000 original documents).
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If the G10 gets anymore of a boost in climb performance, that bad boy needs to get perked.
-SW
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Using the "60%" rule, 1800 hp would give a 7500 lb G-10 a 4752 fpm climb rate. Pretty damn close to the HTC chart also!
I think Wells and Hohun are on to something.
BTW
This is also a very similar weight and hp to the Spitfire LF IX, which also had peak climb rate ~4700 fpm.
Extending "60% rule" to the Spitfire XIV with 8475 lb and 5000 fpm, shaft power required is ~2150 hp.
It's common for Spitfire books to report only military power ratings, not combat power ratings. For instance LF IX always shows up as 1580 hp in books, when the actual combat power was about 1800 hp.
So I wonder if "2035 hp Merlin 65" had a bit higher combat rating. I have some photocopies from a book with all the combat power ratings for Merlins, Griffons, and Sabres, and I will check it out.
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Its just a completely wrong concept to trust allied data sheets more than the original data sheets from the manufactures.
Even when Allied tests show equal or better performance than German tests? Even when Allied sheets are based on actual flying while some German sheets are based on calculations only?
Did you know that most Allied aircraft in AH are not based on manufacturer's data? Do you understand why it might be more reliable to trust the customer's evaluation of a product over the manufacturer's evaulation of a product?
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You donīt want to understand obviously. Those lines drawn in 20seconds are not 100% correct and i donīt want to say the spit performed exactly this way. I just want to give you an imagination about the effect. You better look at the climbrates, which depend much more directly on power instead of speed.
I agree they demonstrate the effect, but that effect is present in the documents I linked to.
Your calculations show speed and climb should both be reduced with an increase in critical altitude.
The documents show that they are, for example the aircraft with 12K FTH is approx 6mph slower at sea level.
I accept the theory, and the documents support the theory. You seemed to be arguing the effect should be greater than the documents suggest.
B) the date in the bottom right corner says July 46. Those charts were made over 1 year later then the end of the war, or 2 years later then the introduction of the Spit14 in the RAF. You have to decide yourself whether you consider those charts, maybe from spits produced under civil circumstances instead of wartime (what also could mean not in armed mode), are representative for a ī44 spit14.
Looking at the PRO catalogue, the charts are probably from the tests carried out on the Hornet.
A few things make me believe they are of a standard wartime Spitfire XIV in combat trim.
1, They match what you could expect from a Spitfire XIV with increased full throttle height.
2. At FS altitudes they match the test results of the prototype Spitfire XIV, which the test reports says was in combat trim.
3. There is little point comparing various combat aircraft if they are not in combat trim.
4. I doubt new performance tests were carried out on the Spit XIV in 1946. It had already been superceeded by the Spitfire XVIII and 21, 22 etc.
5. The report I mentioned on raising the speed of various fighters at 3000 for V-1 chasing was produced in mid 44, and gave the speed of the Spitfire XIV as 372mph at 3K, the same as the later report showed. The prototype Spit did 380 mph at 3000ft.
I have seen peak output quoted for the Merlin 66 as 1670hp or 1760hp. That looks like a misunderstanding to me, but could be a genuine power difference.
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I assume that one power output is for sealevel, the other for the critical altitude of the 1st gear. The power outputs for the RR engines are very often given for the critical altitude of the 1st gear, what is usually higher than sealevel output. The griffon is given with 2050hp, but at sealevel the output was only 1850hp-1900hp. This way the power output looks better, german engines are usually given with sealevl output AND sometimes, especially in case of the 801 with the reduced poweroutput due to rameffects. (static thrust 1800PS, dynamic 1730PS or 1700hp).
No, I am sure the 1760 hp figure is just a misunderstanding of the 1670hp figure.
The Merlin 66 was very similar in MS gear to the Packard -7 engine, and that was rated at 1500hp at sea level, 1670 in MS gear, iirc.
Your second sentence demonstrates your agenda, I think.
Engines can be rated in many different ways. Most people talking about an engine want to know maximum power, so that is what is most commonly talked about. British engines were rated at max, max continuous, 30 min rating etc.
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To sum it up again from history.
Spitfire I vs Me 109E ......on par
Spitfire V vs Me 109F....Spit slightly better if anything
Spitfire Mk IX vs Me 109G2/G6 Spitfire slightly better, increasingly over 19.000 feet
Spitfire XIV vs Me 109 G10.....Spitfire better.
This is what the pilots said. Please post anything you find that indicates the opposite.
Those aircraft being rather closely on par with engine power have a difference rather in favour of the Spitfire, so I at least would point my finger at the wing rather than thrust-to-weight or prop blades etc etc. to explain the difference between the two.
There must be a good equation somewhere to be able to get at least a close guess at climb rate from the input data "wing area, weight and thrust" rather than just weight to thrust as Niklas used in the beginning. Does anyone have it? ??
And now to the "Much superior wing of the 109"
Niklas:
"I really wondered myself when someone brings up the unique "the elliptical wing explains everything" argument. Actually the wing of the 109 was much superior. The wing of the spit can described by only 2 words: wing area. Lot of wing area, thatīs all. No slats, cannons and guns in the wing, only one setting for flaps.. actually a very primitive wing. Nevertheless it can achieve with a very gentle slow speed handling the lift coefficients of a 109 that uses slats and has no disturbing weapons in the wing(same for Tempest, Typhoon), but i already said that i consider RAF planes the most overmodelled ones in the set. The naca test says the spit had a surpisingly low CL btw, and this was a wing with 8*30. Installing the large cannons booms reduced cl by another 2-5% for sure!
What remains for the 109 is the poorer arment of only one central mounted cannon....and even dispersion is very close to that of a spit where the cannons are mounted far outside in a rather "soft" environment (wing)... ahh i better stop... "
Well...:mad:
Here comes an educated lesson in the superiority of an elliptical wing platform:
"The benefit in flight is significant. The amost perfect spanwise distribution of lift combined with the small wingtips reduces induced drag.
This means that the aircraft can maneuvre without substantial loss of performance.
Conversely, an aircraft with straight, constant section wings has a very highinduced drag. It may be fast but it slows when it turns..................
............................. ......The significance of this induced drag is illustrated by the Avions Mudry CAP 10 with its elliptical wing. Although relatively low powered, it can complete an aerobatic sequence without loss off altitude and, if managed properly, can even climb throughout."
(AEROBATICS, principles and practice by David Robson)
So.....an elliptical wing is no laughing matter....it is a seriously superior design in aerodynamic terms. Furthermore, the Spitfire wing was STRONGER than the one of the 109. And finally, regarding the issue of loading guns into it, That was because it was intended to take guns. Although not intended to take the 20mm originally, it could. However, the Wing of the 109 had "structural?" problems with that, so apart from the 109E, the 109 was not loaded with wing mounted guns.
The Spitfire could however have been loaded with more guns near center (cowling, pods or hub) had the designs demanded that. Remember that the reason that the .303's were wing mounted in the first place was that in that way they were able to deliver the maximum fire output, uninterrupted by the engine RPM.
So, what do we yet have in favour of the 109 wing? Well, the slats. Well, that is one double edged sword. For while the inferiority of the 109 wing near the stall could be compensated withg slats, they proved rather a nuicance in combat. In wild maneuvers, turbulences etc the slats were prone to slam out when they were not supposed to resulting in many a pilot having them "fixed" resulting in worse stall behaviour while other aspects remained more predictable.
BTW, weren't the slats originally from Handley-Page...a brithish design,,,,,
So, to sum it up, I have not been able to find any field in which the 109 wing was superior. Apart from the ease of manifacture of course....
Well...there will be some flames...looking forward.
;)
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Oh yes, the Spitfire was just a pathetic design, tremendously primitive. While the German aircraft were all fabulously advanced.:rolleyes:
Talk about transparent agendas.
The Spit and 109 both had innovations in them. They both had strengths. It so happens that the Spitfire was able to develope better than the 109 was. Cie la vie.
Fortunately for the Germans, they had the excellent Fw190 series to step up to the plate. The British had a fighter to do that too, the Typhoon. It was a disaster in air-to-air combat. Fortunately for the British (and us all) the Spitfire proved to be exceptionally adaptable. That is fact.
All of the top end warplanes of WWII (even the much maligned, unfairly I think, A6M) had lots of innovations.
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I dont know how you can say Spit V was even slightly better than 109F. The 109F was faster, climbed faster, dove faster, accelerated better, had similar roll, turned almost as well, its only real weakness vs the spitfire might be in armament- but even on that count I have heard that quite a few senior British pilots thought the light centerline armament more effective vs heavier wing armament.
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If you wanna go say the slats were British, and they were, than I can say that the whole Spitfire wing was German, since it was copied from the He70. No previous Supermarine aircraft had such a wing and the leader of the Spitfire wing design addmited he copied the He70. Of course he was lying because that's just so uncool you know.....
They all copied each other thats nothing new, just like the Grumman Fw-8F! :)
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GRUNHERZ,
I would say that I see the breakdown like this:
Bf109E-4 is better than the Spitfire Mk Ia (Bf109E-4 climbs better, out rolls the Spitfire Mk Ia and isn't handicapped by a float caurburator)
Bf109F-4 is slightly better than the Spitfire Mk Vb (for the reasons you stated, except the Spitfire Mk Vb outrolled the Bf109F-4 significantly)
Spitfire LF.Mk IX is slightly better than the Bf109G-6/U2
Spitfire F.Mk XIV is better than the Bf109K-4 (The Spitfire's better ability to take more power and weight has had a telling effect by this point and the Spitfire has a significant edge)
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@funkeup:
sure it's better to tell from the consumers end, but hell i know HTC doesn't do it.
There is a PRO document (# not at hand, i am at work) and this examines the difference betweem technical sheet data and production machines. The differences are impressive, and as far as i can read the AH charts, those are not for production machines (all nations).
The test flights on the spitpage where all the quotes are from are also no real production machines, they are shiny "performance chart makers".
And the data i mean is from Rechlin, flight evaluation of production machines, no calculations. Problem is the publication of this material is restricted and some things (especially from the FW190) yet have not returned to germany.
And the british airministry admitted that the RAE did some incredible inaccuracies in some test. i.e. the 109E evaluation. In the comments to them, the ministry asks the RAE guys what a roadkill they did by not telling the engine of the 109E was not running smooth.
And i wonder which allied data you mean that shows the german planes better? Every allied charts posted in here show them worse as in GE charts.
Same goes with allied planes in german examinations.
Were might be the reason for this?
It's simple: production machines usually suffer performance losses, but those losses are not modeled in AH. We all fly shiny prototypes, everyone of the same quality not faults no differences.
A little example of what i remember what was found out in Rechlin about 109G+K:
all late 109ers G10-K4 in the chart had climbrates of 20-22 m/s at steig&kampfleistung (climb&combat rating) at sea level, which translates into 3934 - 4327 ft./min. Now if someone can provide a performance chart of the DB605D we could tell how many HPs were used to get that, and what is the HP difference between climb&combat and Special WEP.
I can't provide data special WEP with MW50 cause my time was limited and i was more interested in some new FW190D data and ammunition charts.
P.S.: HoHun, were did i quote 4600 ft./mins? i quoted rougly 3 mins to 16k, which is to me more like 5300 ft./mins for the K4
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Hi Funked,
>A variation of "just 12%" is exactly what this thread is all about.
And I demonstrated that it would take a ridiculous amount of extra drag to generate this small variation.
>The difference between the AH G-10 (4786 fpm) and a nice fat figure like 5300 fpm is "only" 11%.
The difference between 4600 fpm Niklas measured and the 5500 fpm for the 2000 HP Me 109K-4 is 20%.
>No need to accuse RAF or HTC of error or dishonesty.
This is a very unfortunate statement since it places well justified and factual criticism in close proximity of personal attacks. It's also unfortunate by implying that I've posted a personal attack here, which couldn't be farther from the truth. I'd appreciate it if you'd choose your words with a bit more care unless you're trolling for a flame war - which I'm confident you weren't.
Regards,
Henning (HoHun)
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lol, if a differnce of 11-12% is doesn't matter, cause its "just" or "only" that difference, i vote for a test by reducing all Spitfire climbrates by the small amount 10%. :p
Sure if it doesn't matter in a 109 it should not matter in a spit. ;)
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Hi Naudet,
>P.S.: HoHun, were did i quote 4600 ft./mins? i quoted rougly 3 mins to 16k, which is to me more like 5300 ft./mins for the K4
Sorry, I quoted Niklas' numbers, not yours. Your names both start with an "N", that's what confused me :-)
Regards,
Henning (HoHun)
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Hi Hitech,
>Prop designs for climb or speed, the never ending problem gets much worse with more HP.
No doubt we're using crude methods to analyze the game. However, we're fortunate to have the Me 109K-4 for reference which is very similar to the Me 109G-10, so crude methods work quite well for once.
Of course, the analysis is even easier for you since you - unlike us - can actually check whether the Me 109G-10 has a 1800 HP or a 2000 HP engine in the game.
Regards,
Henning (HoHun)
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HoHun, your really think he will post a single ingame number?
When we did our D9 research, he never posted anything, i think this behaviour hasn't not changed.
and with such comments
Prop designs for climb or speed, the never ending problem gets much worse with more HP.
Just curious anyone every think what happens to thrust when the prop airfoil stalls? And hence why the padle blade was devloped?
Or about such simple things as the effect of the prop to eng gear ratio?
HT has lost many trust points to me,
how could we assume gear ratio, if we don't even know what AH uses, or the effect of a paddle blade prob - a 109G has one - if he doesn't give any ingame numbers
many player do researches, have original tables and HT implies that they are generally wrong cause they forget something
but if anyone uses an original chart - even if it only contains peformance calculations - i would say he has a valid point
AH "just" calculates the performances of planes too, based on some "raw" material like drag numbers etc., but as long as HT never posts some of those basics anyone will have a real chance to compare
P.S. just a question of personal interest, is it true that Pyro was the guy back in WB who put some extra weight into the FW190?
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Hohun, sorry about that, didn't mean to accuse you of anything. :(
I agree with you that 4600 to 5500 fpm is too big to be explained by variation in drag or prop efficiency between G-10 and K-4.
All the stuff I was saying about climb rate variation is directed towards Niklas' initial comparisons between different aircraft types. I.e. How could a Spitfire outclimb a 109 which has a better hp/weight ratio? In those cases where you have a big difference in the airframe and prop design, it's clear than you can get significant variations in the climb rate even if power loadings are similar.
But 4600 to 5500 is definitely too much for 109 to 109. Unless the G-10 was turning one of the plastic props from a balsa wood model.
BTW the AH chart shows ~4790 fpm for the G-10. Where do you get 5500 fpm for the K-4?
PS did you read my quick-and-dirty estimates of G-10 hp in AH? It looks like ~1800 hp to me if I assume the Bf 109G-2 in AH has about 1500 hp.
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Naudet
Hitech was merely pointing out things which were missing from the analysis in the original post. As far as him posting his figures and methods, it's quite unlikely. This is proprietary information which he has no doubt spent a lot of time and money to develop. It's not in his best interest to teach us how to make flight models as good as his. :)
About flight test data sources, I think I understand what you mean. Just be aware that most of the USAAF and RAF planes in the game appear to be based on service flight test data, not manufacturer's flight test data. If they used manufacturer's data we would have a 450 mph P-51B among other things. :)
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One more thing - What the heck is a PS?
I only know kW and hp. PS is not used by US engineers.
It seems to be used interchangably with hp, but are we certain that PS and hp are the same thing?
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Funked they are the same according to this I saw on a auto industry website:
"The relationship between horsepower (ps) and torque is expressed by the following formula:"
I think ps might a Japanese term as this was a Mitsubishi website.
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Our P51B does rougly 442mph, thats the same as i found in my books, better it is even a tad faster than the numbers i the books.
But i still use the good old william green books. As US planes interest me not very much i don't own much about them.
Btw i yet never found a source stating a 450 mph P51B.
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Naudet,
Maybe get the America's Hundred Thousand? I don't have that but I've seen folks here quote quite lot of numbers from it on american planes. Nor do I know what it uses as its sources primarily but perhaps someone who owns it can tell.
Shame the LW documents about Allied plane tests are so expensive and under such a license that you can't publish them even if you buy them.
http://www.schifferbooks.com/military/aviationwwii/0764300725.html
// fats
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Originally posted by Wmaker
'
Here's comparision between G-2 and G-10 in AH:
G-2: power/weight: 0.216 hp/lbs. climb on the deck: about 4100ft/min (AH chart)
G-10: power/weight: 0.270 hp/lbs. climb on the deck: about 4600ft/min (AH chart)
So, 25% increase in power loading gives 12% (500ft/min) increase in climb rate. I dunno maybe so...
Actually itīs less than 12%. You donīt have to forget that with zero power, the G10 is gliding. From my eperience you can add 1500ft/min for a 109 without propdrag. So in total the G2 climbs 5600ft, the G10 6100ft. the difference is only 9%
nik
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PS stands for pferdestäerke , which translates as horsepower .
However, when talking about Physics' magnitudes, they are two different things:
(by convention)
1 PS ~ 0.736 kW
1 hp ~ 0.746 kW
1 PS ~ 0.986 hp
So the often (wrongly) quoted power output for DB 605A of 1475 hp is, really, 1475 PS, which is roughly 1454 hp.
For DB 605DB, 1850 PS ~ 1825 hp (C3 fuel or B4 + MW 50)
" DB 605DC, 2000 PS ~ 1972 hp (C3 + MW 50)
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Originally posted by Angus
To sum it up again from history.
Spitfire I vs Me 109E ......on par
Spitfire V vs Me 109F....Spit slightly better if anything
Spitfire Mk IX vs Me 109G2/G6 Spitfire slightly better, increasingly over 19.000 feet
Spitfire XIV vs Me 109 G10.....Spitfire better.
This is what the pilots said. Please post anything you find that indicates the opposite.
Lol define "worse" or "better". Do you have only the slightest imagination about what pilots actually are talking here? Is this all, do you expect the FM modelling based on such statements? Unbelievable.
Here comes an educated lesson in the superiority of an elliptical wing platform:
"The benefit in flight is significant. The amost perfect spanwise distribution of lift combined with the small wingtips reduces induced drag.
This means that the aircraft can maneuvre without substantial loss of performance.
Conversely, an aircraft with straight, constant section wings has a very highinduced drag. It may be fast but it slows when it turns..................
............................. ......The significance of this induced drag is illustrated by the Avions Mudry CAP 10 with its elliptical wing. Although relatively low powered, it can complete an aerobatic sequence without loss off altitude and, if managed properly, can even climb throughout."
(AEROBATICS, principles and practice by David Robson)
You better start to learn what youīre talking about before you begin to quote wildly statements.
The THEORETICAL elliptical wing has a constant ca over the wingspan. The 100%(!!) rectangular wing has an elliptical distribution. This picture makes it clear:
(http://members.tripod.de/luftwaffe1/sonstiges/fluegelform.gif)
Now what is the difference between a rectangular wing and an elliptical wing?
You can write the induced drag coefficient as
cwi = k*K*ca^2
k is the correction Factor, K is the 1/ pi*aspect ratio
For a 100% rectangular wing the correction factor k is as follow:
AR = 3 -> k = 1.02
AR = 5 -> k = 1.04
AR = 10 -> k = 1.09
So even high aspect ratio wings with 100% rectangular shape have only 9% more drag.
In reality, fighter wingshapes are very close to elliptical ones, so the advantage of elliptical aircraft is marginal compared to a wing of P51, 109, 190 or so with Aspect Ratios between 5 and 6. But the elliptical wing made it unpossible to install features like slats, this was only possible on straight leading edges.
Furthermore you donīt take washout into account. This lift distribution was calculated with a special program, and you can see that washout and other influences can change the lift distribution a lot:
(http://members.tripod.de/luftwaffe1/sonstiges/auftriebsverteilung.jpg)
What WAS actually a serious advantage for the 109 is the higher aspect ratio of 6 compared to 5.5 for a spit. This means you can achieve steeper dCA/dAoA gradients, or in simple words higher CA-values with same AoA. Furthermore it goes directly into the equation of drag with 9% advantage for the 109.
- the wing of the spit has a lower thickness ratio what wonīt allow as high AoA as a thicker one.
- they have guns mounted destroying parts of the leading edge
what leads to earlier stall
- they donīt take use of slats and can only achieve good slow speed handling with a lot of washout giving up lift in the outer region
- the wing of a spit has a lower aspect ratio and wonīt be again able to reach the same CA values like a wing of a 109 with same AoA.
No way that they could achieve the lift coefficients of a 109, but in AH it does, enabling them to do the silliest manoevre. And if you donīt believe it, read this Naca test of spitfire stall characteristics:
http://members.tripod.de/luftwaffe1/aircraft/raf/spit_stalling.pdf
Just a quote out of it:
"The maximum lift coefficients obtained are considerable lower than normal"
And this for a wing without those large cannons....
Many views on the slats are based on tests of emils again. But a emil is not a F, G, or K. AFAIK With the F roller bearings were used in the slats instead of gliding mechanism what improved the symmetrical work of the slats.
So next time learn first before you shout so loud please
niklas
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Naudet, I havent' seen much in the way of manufacturers data on the 109's, but I do know that the 190A8 and the 190D9 in AH are both based upon manufacturers data, because I've repeatedly posted the Focke-Wulf factory performance charts. If you have 109 factory data please post it, I would love to see it.
I also would suggest you pick up a copy of America's Hundred Thousand. Its the best single source of data on American fighters. It contains both manufacturers flight test data and US Air Force flight test data, for every major fighter type the US used in the war. Its easily the best single resource for WWII fighters I have ever seen, even though it only covers US Fighters. I truely wish the same was available for the other nationalities.
Niklas, its really funny that you told me I was full of toejam when I told you that it was a function of prop efficency, but when HiTech told you the same answer, you considered the answer "obvious".
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i canīt understand you vermillion. I brought the same example of the 209 as a reply to your posting and to hitechīs posting. And in both cases my reply was basically that the german prop efficiency doesnīt lack behind the allied ones. And even when it was the case, then not by such a margin that is justifies the difference in climb performance.
What you did, posting "prop efficiency" alone with any further description, examples or logic conclusions, isnīt helpful btw. It just reflect the typcial "non-german" view THAT german equipment was (or has to be) worse in any case. You canīt prove it. But this is typcial too, allied guys just have to throw in "prop efficiency" or "elliptical wing" to justify a non-historical huge advantage while the LW-boy has to do calculations, search original data etc. And if he is lucky he is heard. But only on good days. And when a valid question about FM is not immediatly taken as an insult by HTC. Frustrating.
niklas
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====>:pThe Daimler-Benz DB 605 (http://w1.1861.telia.com/~u186104874/db605.htm):p<====
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Niklas, I'm getting off-scale readings on my roadkill detector!!! :)
Porta thanks for the info on PS!!!
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Hi Funked,
>Hohun, sorry about that, didn't mean to accuse you of anything. :(
No problem, I never thought you were :-) I was just afraid others would misunderstand you and think we were flaming each other, and "contribute". We'd both have become "colleratal damage" then ;-)
>All the stuff I was saying about climb rate variation is directed towards Niklas' initial comparisons between different aircraft types.
Yes, though one can learn something by the comparison, the problem is that you'll end up comparing one set of uncertain data to another set of uncertain data, which doesn't help the discussion.
>BTW the AH chart shows ~4790 fpm for the G-10. Where do you get 5500 fpm for the K-4?
That's a frequently quoted figure for the K-4, for example by Green and by Griehl, too. Climb is 3 min to 5 km, which gives an average of 5500 fpm.
>PS did you read my quick-and-dirty estimates of G-10 hp in AH? It looks like ~1800 hp to me if I assume the Bf 109G-2 in AH has about 1500 hp.
The DB605A rating was actually 1475 HP, I think, but I'd say you've got another piece that fits into the puzzle there.
Regards,
Henning (HoHun)
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Porta, can you give me the source for you ps definition?
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HT check this: http://www.flash.net/~lorint/lorin/convert.htm
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HoHun,
Check out DB 605 manual. It reached it's peak power at about 2km and there it did about 1520hp (2800rpm 1,42ata). The supercharger of the DB 605 worked like a single speed system below 2km and above 5,7km, therefore power output increases from sealevel to the altitude where variable speed system starts to work (at higher MAP this altitude would be lower).
gripen
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Well, it is taught in german high schools, but I got definitions some time ago from the astrophysics faculty of Bonn's university. It is the metric horsepower (735.499 Watts):
Germany: PS (Pferdestärke) 736 W
France: CV (Cheval-vapeur) 735 W
Italy: CV (Cavallo vapore) 735 W
Spain: CV (Caballo de vapor) 735 W
You can find it in every german encyclopaedia.
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Look how eager HT is to find an excuse to cut the power of German engines.......
Its only half joke, so feel free to get only a little bit pissed whoever is not in agreement on what I said.... :)
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I think PS is a nice round number in metric,
1 PS = 75 kg.m/s
Whereas 1 HP converts from 550 lbs.ft/s to something like
76.12 kg.m/s
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Grunherz, don't fear that all data we gave HTC had metric system.
No matter what he does, if the GE planes get slower after his PS-to-HP convert, we know that something is definitivly wrong.
But what really scares me is that a guy who models WW2 planes for years doesn't know that PS is not excatly the same as HP. So much to his exact knowledge of the basics. :eek: :rolleyes:
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Well, all post is very interesting.
At that conclusion we can arrive?
I continue saying that the 109 in all their variants this badly modeled, Niklas and others estan (I create) in agreement with me.
Is going to have any change in the 109? (or in Sitfire?)
Supongo
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Originally posted by Naudet
Grunherz, don't fear that all data we gave HTC had metric system.
No matter what he does, if the GE planes get slower after his PS-to-HP convert, we know that something is definitivly wrong.
But what really scares me is that a guy who models WW2 planes for years doesn't know that PS is not excatly the same as HP. So much to his exact knowledge of the basics.
Lemme see if I've got this right...
IF[/B] there was a modeling problem based on this translation error, KP/HP taken at a 1/1 ratio, wouldn't that mean that any plane modeled on this faulty data would be overmodeled? Now that's funny.
-Sikboy
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Sikboy, i will explain what i mean.
If HT took 1 HP for 1 PS, all GE planes would have a few extra HPs, thats right.
But their performance numbers roughly (in case of D9 pretty exactly) match the numbers from WW2 with a tendency to fall short.
Therefor they are not overmodeled with the higher available power, they are modeled on the point.
Now if HT takes away those extra HPS, they would all become undermodeled, cause they would suffer in speed and climb and would fall further below WW2 numbers.
And if this is so something different than HPs must be wrong, which can be drag or weight.
You see, that way two faults in the FM would make them perform properly while only one would make them mismodeled.
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lol, keep plugging away at it.
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"But their performance numbers roughly (in case of D9 pretty exactly) match the numbers from WW2 with a tendency to fall short. "
Yet you squeakes still whine.
Which is it? Are they on the numbers or not?
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Originally posted by Naudet
A little example of what i remember what was found out in Rechlin about 109G+K:
all late 109ers G10-K4 in the chart had climbrates of 20-22 m/s at steig&kampfleistung (climb&combat rating) at sea level, which translates into 3934 - 4327 ft./min.
(http://www.hitechcreations.com/pyro/109kclimb1.jpg)
(http://www.hitechcreations.com/pyro/109kclimb2.jpg)
I would have fun at this point with a little turnaround satire questioning your integrity and competency but I'm sure the irony and humor would be missed by some so I'll refrain.
There is no proof, there is only evidence. Typically, the more evidence you collect, the more questions that are raised. It doesn't just all fit together to form a perfect model. If you only look at one thing or only from one side, it seems pretty clear, but that doesn't make it so. If our roles were reversed and it was you that modeled the G10 in the game, I could offer this "proof" of how overmodeled it is and how biased you are towards German planes. Do you see the irony?
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Originally posted by Pyro
If you only look at one thing or only from one side, it seems pretty clear, but that doesn't make it so. If our roles were reversed and it was you that modeled the G10 in the game, I could offer this "proof" of how overmodeled it is and how biased you are towards German planes. Do you see the irony?
Wahhoooo I was right! Kiss my bellybutton everyone there is no holy grail!
Oh wait, 10 to 1 someone comes in an explains how that chart actually says the planes are undermodeled.
-Sikboy
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Hi Pyro.
First i want to ask you whether you received my mail some weeks ago, if not please sent me one thank you.
I must admit that i wasnīt happy at all with Naudets pretty personal statements (diddlye.. err Funkedupīs posting was not much better but it showed me at least i was on the right path). I know how difficult modelling is, especially if you try to bring a simple climb chart or speed chart together with a flightmodel where you calculate lift and drag at severeal positions. I know it because i tried the same just for fun for myself :)
Of course i know the picture Nr.1 very well. I only want to say that this chart uses 1250PS for climb power (hp, PS, the difference is small. Naudet, if you read this, model same speed with less hp means better aerdynamic btw)
Itīs interesting to see that the oil injection of the second cicuit in the supercharger coupling was dependant on the installation. 2km without MW-50, 0.5-0.9km for 1.8-2.0ata basis
So chart 1 uses later "simple" D2 engine without MW-50 but with enlarged charger and 1250PS for climb and combat power (~1,3ata)
Chart nr.2 shows some other nice details, the increased boost for Steigleistung is noteworthy and confirms my doc that says 1550hp with 1,50ata the first D engine.
Anyway, the most important - and the reason why you posted it - of the chart is the pretty low climb rate for 1,8ata. Iīd really like to know why 1,8ata has different climbrates depending whether the engine was cleared for 1,8ata or 1,98ata.
BUT i spot a little contradiction in the chart. Just look at the left curve that tells you altitude over climbtime. There the 109 reaches 8km in 5minutes. This is equal to 26.66 m/s climbrate.
Soooooo, is it *maybe* possible that instead of 21.5m/s it should mean 26.5m/s and the man who is responsible for this chart just did an error shifting the climbrate curve one tick mark (5m/s) to the left ?
niklas
*editied the chart says no use of MW-50 in the header. Just asking myself now where the weight of 3400kg comes from.
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Here you go:
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Originally posted by funkedup
Here you go:
LOL Thank you, Thank you... It's a gift I have.
-Sikboy
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HoHun,
Second oil pump of the supercharger started work when first one could not keep up wanted manifold pressure. Therefore it's a bit od that in the second chart peaks are at same altitude with all manifold pressure. Peaks should be higher at lower MAPs.
gripen
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A few things to clear up:
1st if someone studies my latest responses to Mandoble or any other post regarding FW190D9 speed or climb, i said that the AH D9 is right, that it flies on the numbers. So i don't squeak against it, i defended it against questione to increase its speed or climb.
To the G10, i was just reposting to Niklas post, and i admit that my knowledge of the 109 is far far away from the information i have for the D9.
And the documents i saw, were roughly 100 pages, including every little detail of the G-Series. I would really like to have copied em, but as i said, the archive restrics such things. And on the same day i saw a few dozen other documents (mainly on ammuniton, amored glass etc.) each containing lots of sites. So please if i remember wrong, than sorry i remember wrong. I DID NOT said i know it excatly!
I never ever stated i have any clue of aerodynamics or such things. If it comes down to calculations i ask people like HoHun, Niklas or Wells.
But such basics like 1PS = 0.986 even i know and it didnt not even take 2 minutes to find it out.
And if you now say, you model AHs K4 on the charts you posted, its OK. Cause than i have an idea which data your FM is based on.
That is my main critic to HTs answers, he doesnt give such things. One such chart, and the thing is cleared for me. Point.
To niklas:
hp, PS, the difference is small. Naudet, if you read this, model same speed with less hp means better aerdynamic btw
i know the difference is low
but ain't the second part what i said, just inverted?
I said if you model a few extra HP (lets say cause you took 2130 PS for 2130HP instead of the 2100HP they really are) and hit the numbers, you are working with worse aerodynamics.
That's right, or not?
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No naudet, that is not correct.
It can all be absorbed by prop eff curves. So if you are refering to worse dynamics of the prop yes, but the plane can be exactly the same.
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Somebody needs to hi-jack this thread! :D
Regards, Shuckins
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As i said, i have no clue of the factors influencing drag and aerodynamics.
My idea was (very) basicly this.
We have a forward force consisting of engine power/thrust
and this is counteracted by overall drag.
At Topspeed i have thrust = drag.
So if i if increase thrust (i.e. more engine power) i get a little bit more thrust to accelerate and increase topspeed until
thrust = drag matches again.
is that right so far (remember that english is not my motherlanguage so my terms might be a little bit of :) )
but if at the same time i increase a drag factor, i might be able to get the exact same speed as if both factors were lower.
I also recognize that there are other factors influencing that, such as prop efficiency, as it effects the way engine power is converted into thrust
so if i use a thumbrule of
power x prop efficiency = thrust
if i now increase power, i would get more thrust, but if at the same time i lower prop efficiency thrust can be constant.
If the above is right.
Than my general statement, that 2 little faults might eliminate each other without affecting the results (here speed), while just 1 fault would changes the result, is right?
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Hi Niklas,
>Chart nr.2 shows some other nice details, the increased boost for Steigleistung is noteworthy and confirms my doc that says 1550hp with 1,50ata the first D engine.
I've to say I find that chart somewhat confusing.
"Grundeinstellung" ('basic setting') seems to imply that the engine was set up differently (probably with different compression values?) to handle high emergency power boosts.
Apparently, the highest power setting actually used in that test was 1.8 ata - do you have any idea of what power it could have yielded? Your suggestion of 1550 hp would result in a 20.1 m/s climb rate according to my crude estimate, which matches the 1.8/1.98 ata branch quite well.
>BUT i spot a little contradiction in the chart. Just look at the left curve that tells you altitude over climbtime.
I'd say the scale is 1 cm = 100 s, this seems to fit the climb rate data.
Regards,
Henning (HoHun)
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Compression was always 8.x for the D engines and ASC. No, it looks like they compared a DC and ASC engine that run with reduced boost like a DB and ASB engine to a real DB and ASB engine. So Grundeinstellung 1.8 seems to refer to xB engine, 1.98 to xC engine.
This makes sense because my docs say 1430PS Steigleistung for DB engines and only 1370 for DC engines. If you assume also same boost for Notleistung the power the power seems to be 1800PS for the DC now, and 1850PS for the DB or DB-basis what is sure and documented (http://members.tripod.de/luftwaffe1/aircraft/lw/DB605_varianten.pdf)
Because they used only 1.8ata they were able to use C3 fuel without MW-50. I just want to know why weight is still so high.
That the scale could be 100s is a good oberservation, this makes sense and seem to fit - pretty unusual though. Funny that i heard people so far speaking about 8km in 5minutes for the 109K. Same source, same misunderstanding?
Itīs a calculation anyway, probably like the first one with safety factors. Other real testflight docs quote 1,98ata but only 1.30 ata for climbpower. This makes everything even more confusing. It would be interesting to know in which context this doc was made.
niklas
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Originally posted by niklas
...... I just want to know why weight is still so high.
Its the weight w Gondolas.
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Correct Naudet
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How about that middle east huh?;)
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Hi Niklas,
>If you assume also same boost for Notleistung the power the power seems to be 1800PS for the DC now, and 1850PS for the DB or DB-basis what is sure and documented.
I'm afraid the document you linked doesn't provide numbers for anything above 1.50 ata without MW50.
>Because they used only 1.8ata they were able to use C3 fuel without MW-50. I just want to know why weight is still so high.
No idea. Griehl quotes the climb data from this sheet for the Me 109K-6, which had MK108 wing guns, so perhaps it was a projection for this type. (Note the "Forschungsanstalt" in the upper left hand corner - this was not "Erprobung" of operational aircraft.)
>That the scale could be 100s is a good oberservation, this makes sense and seem to fit - pretty unusual though. Funny that i heard people so far speaking about 8km in 5minutes for the 109K. Same source, same misunderstanding?
Yes, that's the source for the most often published Me 109K-4 climb data - 3 min to 5 km, 5 min to 8 km, 6.7 min to 10 km, 10.2 min to 11.8 km. Green, Griehl, Elevon ... all wrong :-)
>It would be interesting to know in which context this doc was made.
Do you understand the reference to "Schrb. 12199 z. 12159"? Could it have been a propeller test? (There's also a reference to "9-605-2290/91" - sounds like a RLM engine chart to me.)
Regards,
Henning (HoHun)
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Because they used only 1.8ata they were able to use C3 fuel without MW-50
What was the maximum boost for c3 with mw-50, and for b4 with mw-50?
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Forschungsanstallt Oberammergau? Hmmmmm never saw anythink from this. Must be a Test from the Hofbräuhaus :D
Was in Oberammergau a Maschienen-Prüf-Stand?
Henning did u have any sources from Luftschrauben Tests?
The first chart is from other source but not Rechlin.
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Wulfmen,
The first chart appear to be one of those Messerschmitt project papers which are available as microfilms from the Smithsonian institute (originals migt be at the Deutches Museum nowadays) It's from early 1944 so those are just calculations.
I'm not sure about second paper, but as noted earlier, the altitude where variable speed system starts to work seems to be same for all MAPs and this is not how system worked, so that paper might be a calculation too.
gripen
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If you need to find the location of a certain archive here is what i know so far:
Messerschmitt archive went to DASA, and Messerschmidt charts that were captured by the allied were given back to Freiburg archive.
Focke-Wulf archive can now be found at the "Technisches Museum Berlin".
Junkers archive is at the "Deutsches Museum" at Munich.
Daimler Benz documents should still be located at the company archive, but this is restricted to invited guests.
Btw, i have heard if you ask the folks in Freiburg if the USA and GB gave back all documents, you just get a smile. So there might be more than a few microfilm copies left in the USA, especially FW190 documents seem to have "disappeared" in the last 50 years.
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Naudet,
Some of the stuff captured and microfilmed by USAF are nowadays at Deutsches Museum. Many documents there have Wright Field stamps on them.
gripen
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Good job guys. :)
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Originally posted by Pyro
(http://www.hitechcreations.com/pyro/109kclimb1.jpg)
(http://www.hitechcreations.com/pyro/109kclimb2.jpg)
I would have fun at this point with a little turnaround satire questioning your integrity and competency but I'm sure the irony and humor would be missed by some so I'll refrain.
There is no proof, there is only evidence. Typically, the more evidence you collect, the more questions that are raised. It doesn't just all fit together to form a perfect model. If you only look at one thing or only from one side, it seems pretty clear, but that doesn't make it so. If our roles were reversed and it was you that modeled the G10 in the game, I could offer this "proof" of how overmodeled it is and how biased you are towards German planes. Do you see the irony?
Your charts show 109k-4 climbrate without MW-50 used.(Note o.=ohne=without MW-50) Which is 21.5m/s.
It's no irony.
Now let us see 109g-10 with 27m/s climb. :)
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Interesting thread. Is Illo right?
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Thannks for the awsome thread you egg heads...
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More 109s, more color schemes. The luffwaffe planes R undermodeled in the game IMHO.
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Originally posted by Hortlund
Interesting thread. Is Illo right?
Yes and no.
Yes, o. MW-50 means ohne MW-50, without MW-50. 1750 PS.
No, climb should be more like 25m/s with MW-50, 2000 PS.
check this out: http://pub47.ezboard.com/fallboutwarfarefrm31.showMessage?topicID=111.topic
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Interesting thread.
Did AH 109G-10 had 2000hp? Can anyone say what engine was used on AH 109G-10? There were five different engines in G-10's:
DB605 AS: B4 fuel, 1435 hp
DB605 D: C3 fuel 1550 hp
DB605 D-2: C3 or B4 1435 hp (B4 with MW-50?)
DB605 DC: C3 + MW-50, 2000 hp
DB605 DB: C4 or (B4 + MW-50), 1850 hp
Figures taken from DB605 site (http://w1.1861.telia.com/~u186104874/db605.htm)
Let's try to approach this "problem" from another perspective, it's futile to argue about real G-10's performances because of variations. Some were delivered with different engines, with different wings, with different tails, with different landing gears etc. There were short of everything in late war and that led to equip planes what ever was available. Let's have a good look at the AH G-10.
It was flown by Franz Wienhusen from JG-4 (November -44?).
Only few images could be found from the net:
(http://www.kolumbus.fi/cool/g-10.jpg)
This is a drawing, but only one to give more details from the nose.
(http://www.kolumbus.fi/cool/g-10_2.jpg)
No nose visible, but MW-50 tank is, so what we know for sure is that AH G-10 should have MW-50.
Now, let's have a look to first image.
1. This bulge is required when DB605D was used (also G-10's with DB605 AS engines has these)
2. Larger oil tank was used with DB605D engines. This one could be the most important hint. Were there AS engines with larger oil tanks? If AS engine with normal oil tank was used, it would require some additional modification on oil fill system.
3. Larger Fo 987 oil cooler suggests DB605D engine (also G-10's with DB605 AS had Fo 987 oil cooler).
4. Larger intake duct suggest again DB605D engine (also G-10's with DB605 AS had this one).
5. Engine cowling type "100".
6. MW-50
We cannot say for sure which engine this particular G-10 had. Although many hints suggests DB605D (still could be 1435 hp to 2000hp), it could be AS engine too.
Comments?
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Identifying DB605AS vs. DB605D-engined aircraft (http://109lair.hobbyvista.com/techref/as_vs_d/as_vs_d.htm)
Edit: Could someone explain why G10 still got fixed tail wheel (more drag) while F4, G2 and K4 got retractable tail wheel ???
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Yeah, that's why we have the worst Spitfire Mk IX and worst Seafire ever whereas the Germans are saddled with the best Bf109G-10 and a MW50 equipped Fw190D-9. Those poor Germans.
The Bf109G-10 was also in AH from day one of it going live. The Bf109G-10 and the Fw190D-9 cost nary a point to fly, but if you want to fly the equivilent British aircraft you'd better have 60-70 perk points ready and be willing to be handicapped with a "gangbang" icon.
Yup, those Germans sure did get shafted.
Yes, stop the whining and perk the G-10! :)
Fishu gets my vote to lead the brigade....
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Originally posted by Dr Zhivago
Edit: Could someone explain why G10 still got fixed tail wheel (more drag) while F4, G2 and K4 got retractable tail wheel ???
IIRC smaller, retractable tailwheel didn't work well when flying from soft, grass (muddy) runways. Bigger wheel didn't fit to the tailwheel's bay.
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They wanted to raise the nose for ground handling(the number of 109s lost on the ground was staggering.) With that length of strut on the tail weel, it will not fit in the tail. They solved that problem with the K4. wich had a long but retracing tail wheel.
our 109G10 is wrk number 130282..the 130000 series was supposed to have 605D engines...not proof..but another clue..