Aces High Bulletin Board
General Forums => Aircraft and Vehicles => Topic started by: Krusty on November 10, 2005, 09:01:22 PM
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109 E4 rolls like a zero at 400 mph. So does the 109 K4. The 109 F4 rolls pretty bad until you start hitting 175mph, then it gets back to what it normally is (normally in AH anyways). I haven't noticd any change in G6 and G14 is almost just like G6 (flight-wise).
109E-4 still has short span slats. [EDIT: Changed to slats, I typed flaps originally]
So, what's up with the roll rates? Bug or change to reflect accurate roll rates??
109E is no longer the nimble zero it's been since AH2 came out.
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Bf109G-14 felt pretty dang nice to me, but I haven't tried it in combat.
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i cant wait to see the 109F-4 vs Spit V re-match!:p
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109G-14 climbrate is fantastic! when i wa staking off the climb meter was at 3100, hit the wep then the climbrate went over 4K.
note i was carrying 1/2 main tanks
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Roll rate seems unchanged to me.
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G-14 seems to be too slow at higher altitudes.
Sea level - 317mph@1.3ata, 347mph@1.7ata = +30mph
16,000ft - 375mph@1.3ata, 390mph@1.7ata = +15mph
16,000ft is still below the critical altitude, so the speed gain should be similar to sea level, ie: G-14 should do 405mph at least!
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Sea level - 317mph@1.3ata, 347mph@1.7ata = +30mph
16,000ft - 375mph@1.3ata, 390mph@1.7ata = +15mph
16,000ft is still below the critical altitude, so the speed gain should be similar to sea level, ie: G-14 should do 405mph at least!
That's down to the nature of the DB's hydraulic coupling, surely? (less power required to maintain a particular boost pressure at low level than high, 1.7 ata at sea level should require little from the supercharger with RAM)
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Hydraulic couple doesn't do anything at s/l, it kicks in at about 8000ft(lower if using MW50 boost, at about 3000ft) - and at critical altitude it's not doing anything again(~16400ft if using MW50 boost).
German charts show about 30mph improvement with MW50 boost up to critical altitude(see here (http://www.spitfireperformance.com/spit14v109.html) - compare the pink and red curves).
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At 16k the G-14/AS, according to the chart you linked on Mike's site, does about 392 mph.
If the AH G-14 does 390 it may have the performance of the G-14/AS. What's the speed at 24.5k? 415mpg like the chart on Mike's page?
Even the deck speed, 347mph vs 342mph (see chart) is a bit low (352 for the G-6/R2 mph).
I haven't done any tests myself on AHs G-14, I will try to get to it later tonight.
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Originally posted by justin_g
G-14 seems to be too slow at higher altitudes.
Sea level - 317mph@1.3ata, 347mph@1.7ata = +30mph
16,000ft - 375mph@1.3ata, 390mph@1.7ata = +15mph
16,000ft is still below the critical altitude, so the speed gain should be similar to sea level, ie: G-14 should do 405mph at least!
Official figures for the (clean) G-14 maximum speed w. MW50 were 568kph/352mph at SL, and 665kph/413mph at 5000m/16400 feet.
Your data measured in the sim is well below the historical specs of the G-14, it's too slow.
Care needs to be taken with Mike's site, it doesn't list any 109 with full power, and it tends to cherry-pick from the worst results/data, often showing planes with external loads. The G-14/AS is one example, what Mike lists is a variant with external gunpods, not a clean one.
Official figures for the G-14/AS was 562kph SL, 680kph at 7500m.
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Originally posted by Kurfürst
Official figures for the (clean) G-14 maximum speed w. MW50 were 568kph/352mph at SL, and 665kph/413mph at 5000m/16400 feet.
Care needs to be taken with Mike's site, it doesn't list any 109 with full power, and it tends to cherry-pick from the worst results/data, often showing planes with external loads. The G-14/AS is one example, what Mike lists is a variant with external gunpods, not a clean one.
Official figures for the G-14/AS was 562kph SL, 680kph at 7500m.
If Mike did not state the ata for the a/c, the source of the data and that gondolas were fitted for the graph lines, then you would have a reason for your whines.
Mike states, "The GL/C-E2 for a clean G-14 with ASM engine gives 348mph(560kph) at Sea Level and 422mph(679kph) at FTH."
So you whine about a -2kph @ SL and and -1kph at altitude.:rolleyes:
Hans Knickrehm of I./JG3 recalled the condition of new Me109G-14/AS's received by his group in Oct 1944:
The machines that were delivered were technically obsolete and of considerable lower quality. The engines proved prone to trouble after much too short of time, because the factories had had to sharply curtail test runs for lack of fuel. The surface finish of the outer skin also left much to be desired. The sprayed on camoflage finish was rough and uneven. The result was a further reduction in speed. We discovered clear cases of sabotage during our acceptance checks. Cables or wires were not secured, were improperly attached, stretched or even been visibly cut.
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Yeah, I agree Milo, Mike's site is a bit selective of the facts and hardly anybody takes it seriously given the amount of bias in it.
The things you mentioned are typical examples : he's familiar with the clean G-14 performance, but only shows the graph for the gondola equipped ones. etc.
My personal favourite is though the strory he made up about the groundcrew being transferred to the infantry. Now that's really original.
This guy is really desperate, and appearantly hates the 109 more than he loves the Spit, given the sheer amount of material aimed to show the 109 in a bad light, well, with a bit of help from Mike. OTOH, not a single difficulty with the Spitfire is mentioned. It was a flawless design, and the 109 a complete crap, oh yeah, sure. I think the fact that not even the most die-hard Allied fans bother to qoute the site as a source tells it all. The attitude is too bothersome, even for them.
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Some further testing has revealed these facts:
1. AH Bf 109G-6 speeds match the red curve(G-6 Start-Emergency (1/27/58/44)) from the previously linked-to chart.
2. AH Bf 109G-14 also matches this curve at 21000ft and higher(ie: 395mph@1.42ata/2800rpm).
3. AH Bf 109G-14 is SLOWER at its critical altitude of 16400ft(390mph@1.7ata/2800rpm), even though it should have about +300PS more than at 21000ft.
Two things IMO are wrong here:
1. Considering the shape of the performance curve for the G-6/R2(DB 605AM) and extrapolating from the AH G-14's s/l speed of 347mph, the AH G-14 should be capable of least 407mph at 16400ft(Which is still less than the real life data states, but my main point is the relative disparity between speeds at s/l and at critical altitude).
2. With MW50 activated above critical altitude, iirc there was still a small power advantage -> G-14 should be a little faster than G-6 above 21000ft.
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I just ran some quick level speed tests for the G-14:
AH2 BF 109G-14 level speed tests
100% Fuel, FBM = .001 (minimum; no fuel burn)
1 x 1 MG151/2cm 150 rounds
100ft
WEP - 350 mph
MIL - 320 mph
5000ft
WEP - 369 mph
MIL - 340 mph
10000ft
WEP - 379 mph
MIL - 357 mph
15000ft
WEP - 388 mph
MIL - 366 mph
16400ft (FTH?)
WEP - 390 mph
MIL - 370 mph
20000ft
WEP - 397 mph
MIL - 377 mph
24500ft
WEP - 388 mph
MIL - 378 mph
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Originally posted by Bruno
I just ran some quick level speed tests for the G-14:
AH2 BF 109G-14 level speed tests
100% Fuel, FBM = .001 (minimum; no fuel burn)
1 x 1 MG151/2cm 150 rounds
100ft
WEP - 350 mph
MIL - 320 mph
5000ft
WEP - 369 mph
MIL - 340 mph
10000ft
WEP - 379 mph
MIL - 357 mph
15000ft
WEP - 388 mph
MIL - 366 mph
16400ft (FTH?)
WEP - 390 mph
MIL - 370 mph
20000ft
WEP - 397 mph
MIL - 377 mph
24500ft
WEP - 388 mph
MIL - 378 mph
Good numbers Bruno.
I just ran some speed tests with 25% fuel (zero burn). The purpose was to find the absolute maximum speed at the plane's best altitude. This is what I got (via E6B).
20,000 ft
ATA 1.48
399 mph
21,000 ft
ATA 1.42
401 mph
22,000 ft
ATA 1.36
399 mph
So, it appears that the 109G-14's best altitude is 21,000 feet. How that compares to actual test data is for our Luftwaffe experts to determine. However, the data is accurate for that specific fuel load.
My regards,
Widewing
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Mike's site is less selective and biased than your Kurfurst site, Kurfy. You only whine about it because the truth hurts about your beloved 109. I would not mention hatred for the 109, since you have much more hatred and ignorance for/of the Spitfire, or for that matter, anything British.
Yes, be sure, Mike's vivid imagination has the blackmen being transferred to infantry. :rolleyes:
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Been flying some of the new birds.
I liked the G-14. Was able to outrun a Spit XVI and a KI 84 on the deck, merge with them and outrun them again.
That said, the Spit XVI is quite a killer. Frigging awesome aircraft. But the best one to use for killing it, I found to be the Spit VIII.
Both seem to be somewhat under the performance I expected, but I'll have a look at it. Well, they're only +18 boost anyway, one would have to perk the + 25's.
Any LW data on G-14 actual data? I think it is fast and quite delightful, and it's going to be me new 109 friend. Either that one or the 109F ;)
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Originally posted by Widewing
So, it appears that the 109G-14's best altitude is 21,000 feet. How that compares to actual test data is for our Luftwaffe experts to determine. However, the data is accurate for that specific fuel load.
My regards,
Widewing
LW speed data generally refers to 100% fuel, as opposed to the RAF standard of 95%.
The G-14's rated alt was 5000m/16.4k ft, where the speed peaked out at 665kph/413 mph, at 1.7ata. Appearantly our G-14 is a bit slow at altitude, but looks about right at low alts, I have to check out exactly.
Above 5000m the G-14 should be only somewhat better than the G-6. The boost increase 1.42->1.7 enabled by MW50 would gradually decrease above the rated alt of 5000m, however, MW50's charge cooling qualities did not, and these yielded around 4% power increase even when boost pressure was the same compared to w/o MW50.
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German docs I posses show the climb rate for the G-14/U4 (a bit heavier variant with the MK 108 in the nose) with gondola weapons mounted, at 3501 kg (ie. +215kg becauase of the gondolas) as 21m/sec (4133 fpm) at SL, rising to 21.9m/sec (4300fpm) at 800m.
The 'normal' variant we have was about 50kg lighter, which would mean around .5m/sec added to the climb rate.
Other docs show the effect of removing the gondolas as + 2 m/sec for a 'clean' fighter, so the clean G-14 should be around 23 m/sec at SL, and or about 4550 fpm, rising to 23.9 at 800m (4700fpm).
The values are for a fully loaded fighter with the radiator flaps half-open to keep the temperatures rather below the max. operating temps of the eng.
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Hey Kuffie:
"LW speed data generally refers to 100% fuel, as opposed to the RAF standard of 95%.
The G-14's rated alt was 5000m/16.4k ft, where the speed peaked out at 665kph/413 mph, at 1.7ata. Appearantly our G-14 is a bit slow at altitude, but looks about right at low alts, I have to check out exactly. "
The RAF tests I've seen always refer to tanks fully loaded. So when are they completely full? Depends on the angle of tanks or rather the position of the filling, or did they jostle the aircraft and raise the tail to get everything full to the top.
Anyway 5% on a Spit or 109 is about the weight of a Gallon. About the margin whether the pilot is hungry and just took a crap, or the opposite :D
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In the case of the Bf109G-14 in AH, all things being considered, I would prefer to see HTC use the higher performance numbers.
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Originally posted by Karnak
In the case of the Bf109G-14 in AH, all things being considered, I would prefer to see HTC use the higher performance numbers.
timeout, which one u wanna see?:p 109G-14 was fitted with 2 diffrent engines... THe DB-605AS or DB-605AM. heh i dont even know which 109G-14 engine does AH have...
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@Angus, if you take a look at RAE speed curves, most of them note the results are corrected to 95% takeoff weight. There are a few exceptions of course. I think they opted for an avarage, half fuel load value as standard.
5% takeoff weight diffo is quite a lot btw. For a mk9, it's around 370 lbs...that's quite a poop. :D Or about half the weight of the internal fuel load. How much it would effect max speed depends on the altitude - more weight requires higher AoA in level flight, thus means more drag, the speed diffo is afaik 1-2%, ie. 4-8mph, and should be more noticable above rated altitude. but that's just a sidenote.
@1K3. I think our one has the low altitude AM engine. It makes sense since it's an important model, and the high alt ones are more-or-less represented by the 109K. BTW, there was a 3rd engine mounted in the G-14/AS versions, the 605 ASC, 2000 PS output, similiar to the 605DC of the 109K.
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Kuffie! You mentioned FUEL WEIGHT in your initial post.
Your words:
"LW speed data generally refers to 100% fuel, as opposed to the RAF standard of 95%"
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If HTC would state which data they used and what engines they are using, we would be saved from a whole lot of BS. It should be in their interest too.
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How did they do a speed test with full fuel? DTs?
A few min climbing to full throttle height & another few accelerating at mil power should get to well below 95% fuel, shouldn't it?
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Would be very interesting to know what engine and settings has our G-14.
Sure it looks *slow* at 20K+, if compared to the C.205 with the old, early war DB605A-1 (about 400mph at 21-22K).
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I like 109s and fw 190s.
:p
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Originally posted by senna
I like 109s and fw 190s.
:p
So do I. :p
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;)
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Originally posted by gatt
Would be very interesting to know what engine and settings has our G-14.
Sure it looks *slow* at 20K+, if compared to the C.205 with the old, early war DB605A-1 (about 400mph at 21-22K).
The AS engined 109s required a redesigned cowling. The AH G-14 has the same cowling as the G-6. Speed at 20k isn't the issue so much as it is the speed from 11 to 16.4k (FTH). Above that its speed would be like the G-6 (maybe a little faster but only slightly w. MW50 due to charge cooling). Below 10k the speeds w. MW50 are believable for a G-14 w/ DB605AM. The AS had the DB603 supercharger and wasn't quite as fast the the non-AS G-14 down low. The G-14/AS also had a higher FTH then the non-AS G-14 and was faster at altitude (similar to the G-10 420-425 mph).
At FTH the G-14 should do about 410mph or so. It hits just 390mph @ 1.7ata and 2800rpm. Which is no better then the G-6 @ 1.42ata. It doesn't weigh any more then the G-6 and certainly doesn't have more drag.
See Kurfürst reply above
G-14 maximum speed w. MW50 were 568kph/352mph at SL, and 665kph/413mph at 5000m/16400 feet
Official figures for the G-14/AS was 562kph/350mph SL (w.MW50), 680kph/423 at 7500m/24600ft.
The AH G-14 never even reaches 400mph at any altitude, At 24500 ft I only reached 378 mph. I thing we can assume the AH G-14 in not an AS version and has a DB605AM.
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Thx, Bruno.
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Well, I hope it get's it's speed corrected. It is a nice little fighter, I just can't hit with the 30mm yet. Well, if it is a big, four engined bomber I can, but other than that....
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Will the issues with G-14 be read by HTC in this thread? Or should it get its own thread? Or maybe get posted in the Bug Section of the forums?
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(imo) the G-14 issue deserves its own thread
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I envy you guys who have such an attention to the technical detail. I end up getting lost in a hurry in that.
I just fly that Spit XVI cause it's got clipped wings and a tall tail like my favorite the XII and because it looks good :)
Hope you gents get your 109G14 to where you are happy with it. I couldn't tell you if the XVI is performing like it should, but it feels right when I fly it :)
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Well in order for the issue to be taken seriously it can't turn into a 'woo is the Luftwaffe fan' just like every other thread about LW aircraft does on this forum. Just read the G-10/F-4 threads in the General Discussion section of the forums.
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I couldn't tell you if the XVI is performing like it should, but it feels right when I fly it
it does... :p
It climbs a little better then I expected but still the numbers are believable...
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Originally posted by Bruno
Well in order for the issue to be taken seriously it can't turn into a 'woo is the Luftwaffe fan' just like every other thread about LW aircraft does on this forum. Just read the G-10/F-4 threads in the General Discussion section of the forums.
I'd agree with you. I thought you represented things well in the other thread Bruno.
The hardest part I see in these discussions regardless of the aircraft if folks wanting every last possible option/variant, when that's just not realistic.
Just because it was possible for a fighter to carry a certain load out, for example, doesn't mean we should have it in AH every time.
It's kind of like the guys asking for a Merlin Mustang with 4 20mm cannon because they saw a photo of it once. Or with the Spits, asking for a 4 cannon Spit Vc because it could carry that load. As I say everytime when that comes up, it makes no sense since it was used so rarely operationally.
And as you are pointing out regarding the G14, it's narrowing it down to which G14 it is and getting it right because there were different G14s, kind of like the guy in the Spit question thread screaming he should have an E wing in the AH Spit IX, when the Spit IX ours is modeled on never had an E wing in 42-43.
It goes on and on :)
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Well Bruno, I am by no means versed in Bf109 technical progression, but I certainly understood that the Bf109G-14 would top out at around 415mph. I flew it a bit last night and it is a very, very nice little fighter. I do hope it gets it's performance revised upwards so it hits the numbers it should.
I think that a bug thread would not be horribly out of order, but a dedicated thread in here providing source material to back up the needed correction might be better. Hopefully Kurfurst has some good documentation for the Bf109G-14.
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I have a copy of:
"Hinweise für Technische Aussenstellen (HTA), Neuerungen Nr. 4"
Which clearly states the Bf-109G14 DB605ASM should do 680kph at 7800meters clean using Start-u-Notleistung.
Anybody know of a picturehanger that is working and I will post the relevant portions?
Well in order for the issue to be taken seriously it can't turn into a 'woo is the Luftwaffe fan' just like every other thread about LW aircraft does on this forum.
Largest obstacle to serious discussions on these boards.
All the best,
Crumpp
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yes the G-14/AS was really fast at high alt, but the G14 with the 605AM was a different story.
Crumpp, you could use this to upload the image/s, and then post a thumbnail in the forum (clicking on it you get the original size image)
http://www.potato.com/
Even if AH doesn't have the G-14/AS I think you should post it anyway, your charts are always welcome :)
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Crump,
I also have a place I can host jpeg images. If you want me to, just email them to me and I'll put them up.
My email address is:
aaholaREMOVE@klassyREMOVE.com
Just remove the labeled bits.
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yes the G-14/AS was really fast at high alt, but the G14 with the 605AM was a different story.
I just checked and the DB605AM does do around 666 kph. So there is not much point in posting it.
Meyer I cannot get your link to work. I would like too as there are other documents I need to post. Karnak thank you for the offer. I will keep you email addy in my book if I need it in the future.
All the best,
Crumpp
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Interesting thread.
I took up a G-14 offline, made sure there was no wind. Went up to 21,000 on the button (6400 meters). I got via E6B and confirmed by film, 400 TAS even, sustained using full WEP which was just over 1.4 ATA.
I have no idea if that's a bit slow or not, I suspect it may be.
The only thing I can think of that may drop it @5mph is the large wheel blisters on the wings (some had them some did not?), although Im not suggesting they would have caused some massive ammount of drag, just pointing that out.
P.S. Fuel load was 50 percent at 1.0 burn.
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FTH for the G-14 (DB605AM) is 16400ft (5000m). In AH @ 16400 running at Emergency power (1.7ata 2800 rpm) 100% fuel, 1 x MG151/2cm top speed is 390mph.
If you click on the link justin_g provided (to MW's spit site) you see a chart with a line drawn for the 109G-6/R2. That's basically a G-14. It reaches a top speed of around 410-415mph @ 16400ft.
If anyone has a G-6/R2 or G-14 (non-AS all though all charts are welcomed) kennblatt please post it.
The only thing I recall on the 'web' for the G-14 was a capture report. It was a G-14 that was hit by AA and made an emergency landing in France. If you search the web you will find it (I will post the link tomorrow, I am headed out right now). Before I post in the Bug section I am hoping to come up with some better documentation to show HTC.
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Originally posted by Crumpp
I just checked and the DB605AM does do around 666 kph. So there is not much point in posting it.
Meyer I cannot get your link to work. I would like too as there are other documents I need to post.
Yes, i made a mistake with the link. sorry for the trouble. now it should work:
http://www.potato.com/
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Here is some Bf-109G14 info.
Can anyone answer why the 109 series flaps do not function correctly? Has this been fixed?
(http://img17.potato.com/loc34/th_514_bf109k4_performances_chart1.jpg) (http://img17.potato.com/img.php?loc=loc34&image=514_bf109k4_performances_chart1.jpg)
(http://img41.potato.com/loc31/th_471_109_Flap_deploy_speeds.jpg) (http://img41.potato.com/img.php?loc=loc31&image=471_109_Flap_deploy_speeds.jpg)
All the best,
Crumpp
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Thanks,
The second image is for the a 109E but first chart, (hard to read on my end) seems to confirm what I expected and what Kurfürst had posted. In this case a G-14/U4 (3cm):
568km/h (352mph) 1740ps @ SL
665km/h (413 mph) 1700ps @ 5000m (16400ft)
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Just for info what non-AS powerplants and fuel types could a 109G-14 conceiveably have?
DB605AM with C3+MW50 and what else? Or is that it?
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B4 all though C-3 could be used (not necessarily to increase boost beyond 1.7ata).
In fact here's a link to the captured G-14:
Captured Aircraft Report Me109G-14 W.Nr. 413601 (http://109lair.hobbyvista.com/articles/airframes/413601/413601_report.htm)
it mentions:
This engine has the normal small supercharger and both engine bearers are of light alloy. C-3 (100 octane) fuel is used but additional power for short periods is obtained from an apparatus known as the "MW 50", in conjunction with a boost pressure of 1.7 ata (equals British boost of +9.5). This is a system of delivering methanol and water to the eye of the supercharger from a light alloy tank (probably of 35 gallon capacity) situated behind the normal fuel tank.
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My last Q. would be concerning the fuel then, if its running at 1.7 ATA (as in AH2), lets say, does it make any difference in performance if its running on B4 or C3? If not, then it looks clear that the specs should be modified from what they are. Seems no other non-AS engine was used, and no other sub-type can be the reason for the difference in performance. It should be a FTH of 5000 meters.
Basically a process of elimination. Unless there is an "early" 109G-14 of some type or varient that you guys have not looked at yet. I couldnt find anything that suggested there was.
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The second image is for the a 109E
Flaps mechanism is the same on all 109's.
All the best,
Crumpp
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My last Q. would be concerning the fuel then, if its running at 1.7 ATA (as in AH2), lets say, does it make any difference in performance if its running on B4 or C3? If not, then it looks clear that the specs should be modified from what they are. Seems no other non-AS engine was used, and no other sub-type can be the reason for the difference in performance. It should be a FTH of 5000 meters.
Basically a process of elimination. Unless there is an "early" 109G-14 of some type or varient that you guys have not looked at yet. I couldnt find anything that suggested there was.
No C3 wouldn't make any difference. Max boost was still 1.7ata.
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Originally posted by Crumpp
Flaps mechanism is the same on all 109's.
All the best,
Crumpp
Not so. The E had different flaps than the F, G, and K series. The E had a solid flap with an aerodynamic housing behind the oil coolers, but the F and later had a separate flap for that area, and the oil cooler flaps would change shape with the flaps position.
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Not so. The E had different flaps than the F, G, and K series.
Flaps mechanism is the same on all 109's.
The flaps themselves are different but still most certainly strong enough to be lowered at similar speeds.
They were all lowered using same gearing differential and controls.
All the best,
Crumpp
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(http://img11.potato.com/loc298/th_1b1_109G6R2_8R5_10R2_CURVES.jpg) (http://img11.potato.com/img.php?loc=loc298&image=1b1_109G6R2_8R5_10R2_CURVES.jpg)
Thanks for the potato tip!
Here's the speed curve for the G-6/R2, it's the same thing as the G-14 performance wise (G6/r2 = recce G-6 with camera and 605AM with MW injection). The speed curve (2) for MW50 max power, the climb curve unfurtunately only for 30-min Kamfpleistung 1.3ata. The rest of the data on the chart is basically the same as the doc Crumpp just posted. (Dashed 3) seems to show normal G-6 (or G-8 recce) performance at 1.42ata.
The G-14 used only the 605AM, the G-14/AS either the 605ASM or later the 605ASC. AM and ASM could run on either B4 or C3, the power being the same, C3 being safer for the engine if the MW system fails. ASC was introduced in 1945, and would run on C-3 fuel, either for 1.8ata=1800PS or 1.98ata, 2000PS, a' la K-4.
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I posted this (http://www.hitechcreations.com/forums/showthread.php?s=&threadid=164744) in the Bug Section.
It would be like saying "here is a Merlin 66 Spit graph" and showing the speed and climb of a Spitfire PR XI.
Not really, the G-6/R2 and G-14 differ only slightly, not enough to make any difference in performance...
The G-14 is mentioned in Mtt meetings minutes as the official name of the G-6/MW50 designation which was used internally by Mtt for the G-6 equipped with the MW-50 system (previously used on the recce G-6/R2 variant).
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Yup, I realised that and removed the post. It should be the same given it was an armed recce a/c, more like a Spit FR XIVE in design. I though originally it was a "straight" Recon bird.
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"Flaps mechanism is the same on all 109's.
The flaps themselves are different but still most certainly strong enough to be lowered at similar speeds.
They were all lowered using same gearing differential and controls."
IIRC in FGK models the ailerons drooped a bit as the flaps were lowered. Did the E have a same feature?
-C+
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Originally posted by Charge
IIRC in FGK models the ailerons drooped a bit as the flaps were lowered. Did the E have a same feature?
-C+
The other way around. The Emils ailerons dropped too when the flaps were lowered, the FGK's did not, they were independent.
The G-6/R2 was indeed an armed fighter-recce, like FR Spits, the only difference between the normal G-6 and the /R2 being the latter having cameras in the rear fuselage, and MW50 booster. If anything, the R2 would be somewhat more draggy because of the camera port, nevertheless the German datasheets give the same performance for both FR and and normal F types, ie. the G-10 (F) and G-10/R2 is also noted with the same performance. Now that I think of it, I don't think there was ever an unarmed 109 PR version, the G-4/R3 comes close to this, where the MG17s were removed for extra oil capacity (the plane was for long range recce with 2x300lit DTs under the wings), but it still retained the hub 20mm cannon.
As for the G-14's larger wing fairings, actually they were technically better than the small teardrops used previously, as their transition of the airflow was smoother. Even then, I don't thing those bulges would make any serious difference, maybe 1-2 kph, given drag data from other planes.
-
Pyro replied in the Bug thread:
Originally posted by Pyro
Ok, I'll take a look at changing that.
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Originally posted by Bruno
Pyro replied in the Bug thread:
Yay!
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All performance data in the GL/CE-E dated 13.8.1944 seem to be calculations. The same values in other papers of the same set are marked as "Rechnung".
gripen
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Emil dropped its ailerons 5 degrees when flaps were extended to the max. I read that in the "Bf109 in action" book, I think from Squadron.
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All performance data in the GL/CE-E dated 13.8.1944 seem to be calculations. The same values in other papers of the same set are marked as "Rechnung".
Hardly matters Gripen. Facts are the data matches the manufacturers base for guaranteed performance and are listed in the Flugzeug Handbuch.
This whole line of thinking that "calculations" are always optimistic is pure bunk as well. Aircraft manufacturers tend to be conservative in their estimates not optimistic.
Simple economics. If you cannot deliver what is promised your customers will buy products elsewhere.
Take the Me-262 for example; here are the calculations vs. flight-tested performance. You can see that the calculations are the back curve.
Secondly the middle graph has the data points plotted from over 100 test flights. You can see the wide range of performance exhibited by a given design.
(http://img21.potato.com/loc132/th_20b_Me262performance.jpg) (http://img21.potato.com/img.php?loc=loc132&image=20b_Me262performance.jpg)
(http://img11.potato.com/loc121/th_1e0_262speed.jpg) (http://img11.potato.com/img.php?loc=loc121&image=1e0_262speed.jpg)
I have many such calculations on the FW190A that are slower than the flight-tested data.
All the best,
Crumpp
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Originally posted by Crumpp
Hardly matters Gripen. Facts are the data matches the manufacturers base for guaranteed performance and are listed in the Flugzeug Handbuch.
Hm... if you have flight tested data for the G-14 or G-6, please bring it in. The Me 262 or Fw 190 have nothing to with this.
If you look same set of papers as that GL/C-E data you can find well over 700 km/h claims (with the DB 605A) for the Bf 109G by Mtt.
gripen
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Cut the crap gripen. These specifications are the official figures for the aircraft, and the manufacturer guaranteed performance to be within 3% of that. It's just plain obvious that you got nerveus that the much hated 109 would get fixed and throw in the 'it's only calculated' BS.
"If you look same set of papers as that GL/C-E data you can find well over 700 km/h claims (with the DB 605A) for the Bf 109G by Mtt."
Show those papers if those exists. I've seen one paper claiming 700kph, and it's very clear about the nature of the curve. It was prepeared by Rechlin, not Mtt, and contains simply estimation of the 109G speed calculated from the 109F with the 605A output. The figure isn't unbeliavable at all, considering it's probably not corrected for compressibility and assumes wheel well doors that were foreseen but did not made into the production Gustav, except a few examples. You made a false story out of that on purpose, 'revealing' da great mtt conspiracy to dismiss the official figures. In any case, 700km/h plus speeds would not be anything extraordinary at altitudes considering the GM-1 booster in some of the 109G. With that, the 605A put out about as much power as the RR Griffon, oh, and btw, we have the Spit XIV in the game that is just the like isn't based on any real life flight test results, 'just' calculations.
Your dishonesty is bothering. You have the G-5/AS speed results yourself. You can compare them to those bad bad calculated figures by Mtt for the same plane, and find how closely their calculations match the actual flight data. You probably already did, just playing your usual distgusting games here.
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Gripen,
Once again this performance is listed in the aircraft operating instructions.
Bf-109's could easily attain 666kph in flight:
http://www.beim-zeugmeister.de/zeugmeister/index.php?id=26&L=1
The calculations on the design are conservative:
http://www.beim-zeugmeister.de/zeugmeister/index.php?id=27&L=1
Your pretty much trolling Gripen.
All the best,
Crumpp
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I've seen one paper claiming 700kph,
The Bf-109K4 Handbuch list's 710 kph. It is also listed in:
"Hinweise für Technische Aussenstellen (HTA), Neuerungen Nr. 4"
All the best,
Crumpp
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Originally posted by Kurfürst
Show those papers if those exists. I've seen one paper claiming 700kph, and it's very clear about the nature of the curve.
All you need to do is find a Mtt paper (Datenblatt, errechnete werte) dated 12.5.1942 (among same set as GL/C-E data) and it claims 732 km/h at 7500m (DB 605A, Start- und Notlstg.).
Originally posted by Crumpp
Bf-109's could easily attain 666kph in flight:
http://www.beim-zeugmeister.de/zeugmeister/index.php?id=26&L=1
That's not Bf 109G-14 nor G-6.
Originally posted by Crumpp
The Bf-109K4 Handbuch list's 710 kph
That's not Bf 109G-14 nor G-6.
gripen
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That's not Bf 109G-14 nor G-6.
Again Gripen,
The performance is listed in the Flugzeug Handbuch and forms the bases for the 3% variation.
The posted documents simply illustrate Mtt's numbers are based on fact. Not your silly conspiracy theory.
The flight tested performance listed here:
http://www.beim-zeugmeister.de/zeugmeister/index.php?id=26&L=1
Simply illustrates the point that calculations are generally conservative as shown in Mtt calculated performance of the aircraft flight tested above:
http://www.beim-zeugmeister.de/zeugmeister/index.php?id=27&L=1
The calculations even show less speed for more input horsepower due to the conservative drag figures.
Now about the Bf-109G14 "calculations" which you have yet to show are in fact calculations.
This sheet lists 666kph at FTH on a clean configuration Bf-109G14/U4 weighing 3318Kg.
The flight test sheet for a DB605AM equipped Bf-109G14/U4 with Gondolawaffen with a weight of 3501Kg is listed as 652kph.
666kph as listed by Mtt is clearly within the attainable performance of the Bf-109G14 in clean configuration. In fact I would imagine actual flight performance to be generally better than Mtt's listed 666kph.
All the best,
Crumpp
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Originally posted by Crumpp
The performance is listed in the Flugzeug Handbuch and forms the bases for the 3% variation.
Just post the test data. I'm not interested about the rest.
Originally posted by Crumpp
The posted documents simply illustrate Mtt's numbers are based on fact. Not your silly conspiracy theory.
None of the posted documents are tested data on the G-14 or G-6
gripen
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None of the posted documents are tested data on the G-14 or G-6
I certainly am not going to post them for you horde. You can wonder what happenend and it will be amusing to see your arguments against it.
All the best,
Crumpp
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Originally posted by Crumpp
I certainly am not going to post them for you horde. You can wonder what happenend and it will be amusing to see your arguments against it.
My arguments against what? I can't follow your logic here.
gripen
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Originally posted by gripen
All you need to do is find a Mtt paper (Datenblatt, errechnete werte) dated 12.5.1942 (among same set as GL/C-E data) and it claims 732 km/h at 7500m (DB 605A, Start- und Notlstg.).
gripen
You can give the exact reference to the microfilm and archive so I can find it. Of course, IF you actually have this document. You can reproduce it here if it exists to see what it exactly says, what conditions for the aircraft, and what corrections were or were not made to the data.
732 kph is otherwise very reasonable speed for the 109G-1. The G-1 was rated 650 kph in its official kennblatt with 1,3ata, and with Startleistung 685kph. That's the official data, like the G-14 ones. If you don't like it, come up with your own sources.
GM-1 injection which all G-1s had as standard fitting added 300 HP to the engine, and added 120 km/h to the topspeed roughly 1,5km above rated altidude, which just happens to fit. With GM-1 the DB605A's output was ~1100 HP at 10km, slightly better than the RR Griffon 65. I don't see why the considerably slower 109G with more power would not attain similiar speed than the SpitXIV.
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That speed is ....whooping!
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Originally posted by Kurfürst
You can give the exact reference to the microfilm and archive so I can find it. Of course, IF you actually have this document. You can reproduce it here if it exists to see what it exactly says, what conditions for the aircraft, and what corrections were or were not made to the data.
Well, it's among the same set as other papers posted in this thread but to save some your work, here it is. I'm sure that Pyro will take it just as seriously as above posted data.
gripen
(http://img34.potato.com/loc213/th_c50_732kph.jpg) (http://img34.potato.com/img.php?loc=loc213&image=c50_732kph.jpg)
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That document is unreadable.
All the best,
Crumpp
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Hm... the type of the plane, speed values, weight, the type of the engine, setting of the engine etc. All are readable.
gripen
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gripen,
what IS that plane type? Does it say 500 rounds for the 1 x MG 151?
Is that some kind of spec sheet for some concept?
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The details of the plane (Bf 109 G-1 Endzustand) used for those calculations are shown in sheet IV/31/42. It includes the following improvements over the standard calculated performance of G-1:
- Wheel well doors
- Radiator flaps with improved kinematics
- Surfaces specially treated
In adition, the coolant relief valve setting in VDH is raised to 1,3 to 1,5 atü (standard was 0,75 atü), and the oil cooler intake is also improved.
Another history would be if the calculated performance of the basic G-1 was OK or not...
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The details of the plane (Bf 109 G-1 Endzustand) used for those calculations are shown in sheet IV/31/42. It includes the following improvements over the standard calculated performance of G-1:
There is your explanation, Gripen. I have FW-190 flight-tested performance that gives 700kph at 2nd Gear FTH. The same aircraft is also much slower at sea level.
Hardly typical but well within manufacturers guarantee.
For what it is worth:
German flight testing procedures tend to follow a different format than the allied ones for standard production performance in my experience. While the allies tend to test one or two aircraft producing a report specific to that serial number, the Germans tended to test multiple aircraft over several hundred flights. This can be seen in the Me-262 report posted in this thread.
They then produce a general report describing the average performance and specific aircraft set up used. Mtt will publish calculated figures included in this report as well many times. Focke Wulf does not usually include calculations in the report. A flying schedule and list of pilots and aircraft flown can sometimes be found as an appendix or referenced as a separate report in the case of Focke Wulf, Gmbh.
Focke Wulf produces the calculation reports separately from the flight test as well. These calculations tend to be extremely detailed and all the reports I have for FW-190V5g thru FW-190D15 are several hundred pages of calculations. For example the calculation report for the FW-190A8 are over 500 pages. Calculations are also very distinctly labeled as such.
Mtt will almost always include general calculation sheets as well in flight test reports:
http://www.beim-zeugmeister.de/zeugmeister/index.php?id=28&L=1
As a general trend, calculations tend to be conservative and not optimistic in any aircraft manufacturer. It is just simple economics. Everyone comes out a winner with conservative estimates and everyone looses with optimistic ones.
All the best,
Crumpp
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I can read that document but it could do with a tad of photoshopping.
Interesting stuff.
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Hm... the type of the plane, speed values, weight, the type of the engine, setting of the engine etc. All are readable.
If that is all the detail you focus on, Gripen, then you will draw an inordinate amount of erroneous conclusions.
All the best,
Crumpp
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Originally posted by Crumpp
If that is all the detail you focus on, Gripen, then you will draw an inordinate amount of erroneous conclusions.
I wonder what you might mean, I have not made any conclusions here, merely posted a datasheet from Mtt.
gripen
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From an old post on LEMB (http://www.luftwaffe-experten.org/forums/)
BPNZ
Hi Everyone,
I've got a data chart showing the G14 having the same speed as the G6/R2, both with DB605AM engines:
568km/h (353mph) @ SL
665km/h (413mph) @ 5000m
Felix99
From Datenblatt A/IV/141/44, and charts A/IV/142/44 and A/IV/144/44, for the G-14/U4 w. 605AM
At Take-off and Emergency setting:
557km/h (346mph) @ SL
652km/h (405mph) @ 5000m
At Climb and Combat setting:
486km/h (301mph) @ SL
619km/h (384mph) @ 6600m
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Hi Bruno,
on your second 109G14 Dokument is there a weight indicated?
Maybe the slower speeds are with Mg151/20 gondolas?!
The first Document i now its a clean 109G14-U4 with 3318kg!
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Originally posted by Porta
The details of the plane (Bf 109 G-1 Endzustand) used for those calculations are shown in sheet IV/31/42. It includes the following improvements over the standard calculated performance of G-1:
- Wheel well doors
- Radiator flaps with improved kinematics
- Surfaces specially treated
In adition, the coolant relief valve setting in VDH is raised to 1,3 to 1,5 atü (standard was 0,75 atü), and the oil cooler intake is also improved.
Another history would be if the calculated performance of the basic G-1 was OK or not...
Oh, that makes it clear... gripen was telling half the truth it seems. Rechlin was regularly suggesting possible improvements to the manufacturers about how to improve plane performance, sometimes these were introduced, other times - not. The 109G was originally planned to have well doors, but in the end only a few got them. Just check a 109F wheel well, it's circlur, while the 109G had staight panel towards the wingtip - that's where the wheel well door would have been fitted.
Porta, do you have the complete report? I'd be interested, I've got a lot of 109 stuff, I'll see what I can give you in exchange. My email is kurfurst@atw.hu !
BTW, Leistungzusammenstellung for the 109G notes +10kph for the well doors, +12 for improved finish at SL. That's +22, and to adjust it to the VDH, alone these changes would result +35, plus the other we dont know how much it would worth.
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Originally posted by Porta
The details of the plane (Bf 109 G-1 Endzustand) used for those calculations are shown in sheet IV/31/42. It includes the following improvements over the standard calculated performance of G-1:
- Wheel well doors
- Radiator flaps with improved kinematics
- Surfaces specially treated
In adition, the coolant relief valve setting in VDH is raised to 1,3 to 1,5 atü (standard was 0,75 atü), and the oil cooler intake is also improved.
Another history would be if the calculated performance of the basic G-1 was OK or not...
Using Raunios article and MT-215 data as a baseline, 636 km/h at 6400 m (couple km/h could be added for the slightly lower rpm than the spec):
Tailwheel 10 km/h
Wheel doors 10 km/h (Raunio gives 5 km/h but Mtt test data about 10 km/h)
Polished surfaces 15 km/h
Can't say much about the kinematics of the radiators and oil cooler intake but these were in shut position on the MT-215 speed runs anyway. That will result about 670 km/h somewhere around 6600-6700 m assuming no losses on the propeller. Propeller efficiency curves for 6000 m (both, by Mtt and Raunio) give about 2-3% decrease from 640 to 670 km/h so in practice something around 660 km/h at around 6700 m would have been reachable at 1,3ata 2600 rpm, while the datasheet claims 707 km/h at 7500m. Correcting the FTH to 6700 m for the datasheet gives about 695 km/h so a quick and dirty analysis gives roughly 35 km/h difference between practice and calculation.
gripen
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Originally posted by Kurfürst
The 109G was originally planned to have well doors, but in the end only a few got them.
Actually some FAF Bf 109G-2s had hydraulic lines fitted for the wheel doors and even some G-6s had them.
gripen
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What about the effect of air temp and humidity between calculations and real flight testing?
-C+
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Originally posted by Charge
What about the effect of air temp and humidity between calculations and real flight testing?
AFAIK Mtt calculations are based on CINA atmosphere and in the MT-215 tests conditions were quite near CINA standard (according to the report).
gripen
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gripen,
The calculations for the start model (Me 109 G-1 Ausführung), for which those calculations (Me 109 G-1 Endzustand) were based on, are outlined in sheets IV/42/42 (Vorbemerkungen zum Datenblatt...) and IV/43/42 (Datenblatt...).
The "starting" numbers are (Kampfleistung, n = 2600 U/min):
- 0 m : 535 Km/h
- VDH: 660 Km/h @ 7000 m
With this in mind, the fantastic performance of the "Me 109 G-1 final condition" initially calculated is more "believable". But, as I said, the calculations for the basic model might bring even more heated discussions than the ones you initially showed... ;)
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Originally posted by Porta
The calculations for the start model (Me 109 G-1 Ausführung), for which those calculations (Me 109 G-1 Endzustand) were based on, are outlined in sheets IV/42/42 (Vorbemerkungen zum Datenblatt...) and IV/43/42 (Datenblatt...).
The "starting" numbers are (Kampfleistung, n = 2600 U/min):
- 0 m : 535 Km/h
- VDH: 660 Km/h @ 7000 m
With this in mind, the fantastic performance of the "Me 109 G-1 final condition" initially calculated is more "believable". But, as I said, the calculations for the basic model might bring even more heated discussions than the ones you initially showed... ;)
Yep, I know but I'm merely using the posted datasheet as an example how a calculation (at what ever condition of the plane) can give quite false indication of reachable performance.
Overall the main problem in these calculations (Ausführung or Endzustand) is that the engine did not reach the estimated altitude performance. But even if the engine had lived up to the estimations, the high altitude performance would have been quite bit lower than in calculations, at least with the given propeller. At low altitude the difference to flight tested performance is quite low, say 10-20 km/h but at high altitude the gap is quite large.
Anyway, Mtt was not alone with these estimation problems and that is what I'm promoting here ie importace of flight tested data.
gripen
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Yep, I know but I'm merely using the posted datasheet as an example how a calculation (at what ever condition of the plane) can give quite false indication of reachable performance.
It is not a false indication, you just do not take all the factors into consideration. In short you make assumptions which are not correct.
Anyway, Mtt was not alone with these estimation problems and that is what I'm promoting here ie importace of flight tested data.
Your not promoting anything and how arrogant of you to make such a claim. You simply posted a troll which is a non-issue. The numbers listed by Mtt are flight tested data. The sheet posted in this thread is unknown however it has great agreement with the mean average of flight test data from another report.
There is no estimation or calculation problem except of your own invention.
Calculations are generally conservative and not optimistic.
No one has claimed calculations should replace flight tested data in this thread or anyother thread. Much of the time flight tested data is the better of the two!
What has been shown through documentation is:
1. Flight tested data falls within a wide range of performance based on manufacturers guarenteed percentages within the same design.
To argue over an exact number is rather silly especially when that number is the manufacturer's specification as published by the end user organization.
2. Calculations tend to be conservative not optimistic.
All the best,
Crumpp
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Originally posted by elkaskone
Hi Bruno,
on your second 109G14 Dokument is there a weight indicated?
Maybe the slower speeds are with Mg151/20 gondolas?!
The first Document i now its a clean 109G14-U4 with 3318kg!
I don't have access to the documents. I simply ran accross that info while over at LEMB while looking for G-14 paint schemes for a skin I am doing.
I posted it here in hopes that some one else might have them.
My first thought on the lower numbers was that it may have had gondolas.
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Originally posted by Crumpp
It is not a false indication, you just do not take all the factors into consideration. In short you make assumptions which are not correct.
I have no idea what you are trying to argue, I don't make any particular assumptions. I simply compare documented test data to the calculations.
Originally posted by Crumpp
Your not promoting anything and how arrogant of you to make such a claim.
Maybe you should leave personal attacks out of this thread and post data and facts instead.
Originally posted by Crumpp
You simply posted a troll which is a non-issue.
I have no idea what you are trying to argue, my first post to this thread was simply a note that GL/C-E data seem to a calculation and the Mtt data is an example how some caculations were unreachable in real life due to various reasons (engine not giving the expected performance, propeller efficiency etc.).
Originally posted by Crumpp
The numbers listed by Mtt are flight tested data. The sheet posted in this thread is unknown however it has great agreement with the mean average of flight test data from another report.
If the datasheet says "Rechnung" or "errechnete werte" there is no question if these are calculations or flight tested. If you want to prove that there is a great agreement, just post the data instead personal attacks.
gripen
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just post the data instead personal attacks.
There are no personal attacks in anything I posted, Gripen. You were not promoting anything and are making a baseless claim. Even if the data is calculations, it is conservative and not optimistic. I see nothing on the data sheet I posted on the Bf-109G14 which says calculations. You are the one making that claim and have not proven it.
We only have your word.
Please point out on the data sheet I posted where it says:
If the datasheet says "Rechnung" or "errechnete werte" there is no question if these are calculations or flight tested. If you want to prove that there is a great agreement, just post the data instead personal attacks.
Your "IF" does not apply so far.
I have an actual flight test report as well as the Flugzueg-Handbuch data on the Bf-109G14 to compare. Both say the sheet is well within Mtt specifications for an average performing Bf-109G14 in clean configuration.
I don't make any particular assumptions.
Obviously if you assume all the data you need is:
the type of the plane, speed values, weight, the type of the engine, setting of the engine etc. All are readable.
To determine what the "correct" performance "should be" of a given type then you are making some large assumptions that will often lead you to incorrect conclusions.
Especially if you are trying to compare flight tested data from one or two data points. Good example of your margin of error is found in the Me262 flight test data points:
http://img21.potato.com/img.php?loc=loc132&image=20b_Me262performance.jpg
Mtt data is an example how some caculations were unreachable in real life due to various reasons (engine not giving the expected performance, propeller efficiency etc.).
Sure a few calculations are optimistic. However this is very much the exception and not the rule.
You are trying to create the impression that calculations are almost always optimistic.
Again, examine the Me 262 calculated performance document vs flight tested data. Here is the Bf-109F4 performance estimates:
http://www.beim-zeugmeister.de/zeugmeister/index.php?id=27&L=1
AT 1185PS @ 6KM altitude we see a top speed of 635kph calculated.
In the flight tested data we see at 1180PS @ 6.2KM a top speed of 660kph:
http://www.beim-zeugmeister.de/zeugmeister/index.php?id=26&L=1
A 25kph increase over the calculated performance and very good agreement for a performance estimate.
In the Me 262 we see an increase of almost 50kph in the flight tested data OVER the performance estimate calculations.
The Focke Wulf estimates run about 15kph slower than the flight tested data.
Simply put, you have raised a non-issue.
All the best,
Crumpp
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Originally posted by Porta
The "starting" numbers are (Kampfleistung, n = 2600 U/min):
- 0 m : 535 Km/h
- VDH: 660 Km/h @ 7000 m
Originally posted by gripen
....what I'm promoting here ie importace of flight tested data.
That's great gripen, but tell us first why you presented that calculation in a dishonest manner, telling only half the truth about the conditions? Because it's plain simply to see what you did, you tried to dismiss G-14 saying that it's calculations only (which you did not prove), and calculations are very unreliable, especially that of Mtt. For that you brought us an example that bad Mtt calculated 737 km/h - only you 'forgot' to tell the conditions were special with great change in finish compared to the serial planes, simple to put you manipulated with the evidence didn't you? For the serial condition we are interested in Mtt appearantly calculated, as said :
"(Kampfleistung, n = 2600 U/min):
- 0 m : 535 Km/h
- VDH: 660 Km/h @ 7000 m"
Curiously, the Russians did actual flight tests with a Me 109G-2 at Kampfleistung, too. What happens, they got almost the same numbers as Messerschmitt AG calculated, they got 530 kph at SL (+5) and 666 kph at 7000m :
http://www.pbase.com/isegrim/image/11679724
In other words, Messerschmitt's calculations, which you claim to be non-representative, were SPOT ON on the VDH, and actually pessimistic by 5kph ... here crumbles the theory about calculations being totally different than flight tests.
Rechlin measured 650 kph at 7000m for another 109G-1, for which the plane conditions are unknown, which was the figure that was officially accepted and published for the 109G-1/2 :
http://www.pbase.com/isegrim/image/9759597
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Originally posted by Crumpp
There are no personal attacks in anything I posted, Gripen.
At least in my scale calling some one's actions arrogant is quite personal.
Originally posted by Crumpp
I see nothing on the data sheet I posted on the Bf-109G14 which says calculations.
As noted above in the same data set there is exactly same speed values for the G-14 dated 13.8.1944 and marked as Rechnung just like all other values from the same date.
(http://img106.potato.com/loc169/th_69e_rechn.jpg) (http://img106.potato.com/img.php?loc=loc169&image=69e_rechn.jpg)
Originally posted by Kurfürst
Curiously, the Russians did actual flight tests with a Me 109G-2 at Kampfleistung, too.
Did the Russians actually do the full speed tests?
gripen
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At least in my scale calling some one's actions arrogant is quite personal.
They were arrogant. Spade is Spade. I don't see where it says calculations anywhere on the document you posted. Of course it is unreadable for the most part.
You mean they will clearly be labeled calculations at the top of the page just like this one?
(http://img101.potato.com/loc296/th_c47_page_3G14.jpg) (http://img101.potato.com/img.php?loc=loc296&image=c47_page_3G14.jpg)
All the best,
Crumpp
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Originally posted by Crumpp
They were arrogant.
So in my scale you are taking this personally.
Originally posted by Crumpp
I don't see where it says calculations anywhere on the document you posted.
"Rechn." means "Rechnung" ie calculation. If it's flight tested it should be marked as "Erfolgen" and nothing on these documents indicates that the values are flight tested.
gripen
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grippen,
look the word up from a dictionary.
It refers to your actions, not to your person. One's actions can be seen as aggressive, defensive, arrogant, flattering, etc. It is not like calling you names or such.
Seems to me, that sometimes when you cannot base your arguments on data, you revert to playing silly tricks with semantics. Please look back at the theme of this thread and present your arguments with data.
If your only argument is that calculations do not always provide reliable data, why are you bringing it into discussion about how the "new" 109:s perform in the game? Do you even play the game? Furthermore, your evidence cannot claim that calculations never provide reliable data... so what is the point?
If you want to argue about flight test data and calculation, start a new thread. Include the allied data and calulations to that discussion as well. Actually I have yet to see you criticize any allied data on these boards... then again, I have not been reading such threads with great interest.
It has been interesting, again, so far. Please keep it that way, and dont begin whining about personal attacks when your actions are being criticized.
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IMO, if WW2 engineers could produce calculations that fall within the (usually 3%) tolerance for performance(I believe they could), then it doesn't matter if the data is calculated or recorded from flight.
What DOES matter is the condition of the aircraft in question - as has been pointed out - the 732kph G-1 was not based on a standard condition serial aircraft.
If a calculated data sheet is based on an aircraft of the SAME condition as what was actually manufactured then it should be treated as worthy as flight test data for the purpose of modelling in a computer game simulation!
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Originally posted by BlauK
Seems to me, that sometimes when you cannot base your arguments on data, you revert to playing silly tricks with semantics. Please look back at the theme of this thread and present your arguments with data.
Hm... I have claimed that the GL/C-E data for the G-14 seems to be a calculation and I have posted data which indeed states that the values are calculated ie "rechnung".
(http://img106.potato.com/loc169/th_69e_rechn.jpg) (http://img106.potato.com/img.php?loc=loc169&image=69e_rechn.jpg)
Originally posted by BlauK
If your only argument is that calculations do not always provide reliable data, why are you bringing it into discussion about how the "new" 109:s perform in the game?
Actually the others came up first with the argument on the historical performance of the G-14. I merely posted a note that the so called historical performance seem to be a calculation without any opinion if the calculation is right or wrong. The others started to argue about the validity of the calculations.
Originally posted by BlauK
Furthermore, your evidence cannot claim that calculations never provide reliable data... so what is the point?
I wonder what you might mean, I have not claimed that the calculations never provide reliable data. The others came up with the arguments like "Calculations tend to be conservative not optimistic", my opinion is quite different.
Originally posted by BlauK
Actually I have yet to see you criticize any allied data on these boards... then again, I have not been reading such threads with great interest.
Well, you should dug some of the old P-38 threads.
Originally posted by justin_g
What DOES matter is the condition of the aircraft in question - as has been pointed out - the 732kph G-1 was not based on a standard condition serial aircraft.
What does matter is that the DB 605 did not live up to estimated performance and the efficiency of the propeller at high speed is too low for such performance. See Raunio's article, it contains quite a lot analyses on the Bf 109G.
gripen
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Did the Russians actually do the full speed tests?
gripen
Yes gripen, it was a captured 109G2, I have the Wrknr too somewhere. Butch2k has the full Soviet report on that tests, it's some 17 pages afaik, they did tests with and w/o gunpods. There are even pictures of that plane, posing with the Red Star on it's wings.
In clean config the captured G-2 did 530 kph at SL, 666kph at 7000m, at 1.3ata kampfleistung, within (actually higher) 5kph of Messerschmitt's calculations.
In other words, Mtt's calculations are VERY accurate for the aircraft of the same conditions.
What does matter is that the DB 605 did not live up to estimated performance and the efficiency of the propeller at high speed is too low for such performance. See Raunio's article, it contains quite a lot analyses on the Bf 109G.
Oh well, I guess that's just other claims you need to back up with something...
You need to back up :
"the DB 605 did not live up to estimated performance"
"the efficiency of the propeller at high speed is too low for such performance"
We have already seen how accurate Mtt's calculations were, ie. they calculated 660 kph at 7000m, Soviets actually achieved 666kph with the same type of plane. Pretty convincing, huh?
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Originally posted by Kurfürst
Yes gripen, it was a captured 109G2, I have the Wrknr too somewhere. Butch2k has the full Soviet report on that tests, it's some 17 pages afaik, they did tests with and w/o gunpods. There are even pictures of that plane, posing with the Red Star on it's wings.
So far no one has come up with proofable data from these tests. Infact even those who have supposedly seen the data, have had problems to read the text. It's not known if the data is calculation or real test data.
Originally posted by Kurfürst
We have already seen how accurate Mtt's calculations were, ie. they calculated 660 kph at 7000m, Soviets actually achieved 666kph with the same type of plane. Pretty convincing, huh?
As you have allready seen, the Mtt tested Bf 109G did 626 km/h at FTH 6100m with the 1,3ata and 2600rpm. In the Erla set (13 planes), none of the planes reached 7000m FTH the average being 6700m and highest being 6900m (probably above spec rpm and/or below spec MAP).
gripen
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Originally posted by gripen
What does matter is that the DB 605 did not live up to estimated performance and the efficiency of the propeller at high speed is too low for such performance. See Raunio's article, it contains quite a lot analyses on the Bf 109G.
Exactly my point - the engine power used in the calculations was not the same as that achieved by production aircraft. It's a case of "garbage in, garbage out".
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Originally posted by justin_g
Exactly my point - the engine power used in the calculations was not the same as that achieved by production aircraft. It's a case of "garbage in, garbage out".
OK, if you want to put it that way. To give some idea about the issue, at 10 km the calculated speed for the G-1 (Ausführung) is 632 km/h, which is about the same performance as the prototype 109G-5/AS reached in flight tests with the DB 605 AS and high altitude propeller at same power setting (1,3 ata 2600 rpm).
gripen
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OK, if you want to put it that way. To give some idea about the issue, at 10 km the calculated speed for the G-1 (Ausführung) is 632 km/h, which is about the same performance as the prototype 109G-5/AS reached in flight tests with the DB 605 AS and high altitude propeller at same power setting (1,3 ata 2600 rpm).
What does performance of the production G-1 have to do with performance of the prototype G-5? What a totally silly comparison.
Computations are both aircraft and condition specific.
Flight tested data exhibits a wide range of performance within a given design.
Prototypes can exhibit an even wider range of performance!
With "New Type" aircraft, however, the error might be up to 6-7% in speed, and 200-250 ft./min. in climb.
Only when trials with representative production machines have been carried out under known conditions can the Final figures be issued. These figures then represent the performance expected of an average production machine of this type.
http://www.spitfireperformance.com/
All the best,
Crumpp
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Originally posted by gripen
So far no one has come up with proofable data from these tests. Infact even those who have supposedly seen the data, have had problems to read the text. It's not known if the data is calculation or real test data.
[/B]
Hate to point it out, but butch2k is without exception is a very credible and honest person, who has literally tons of documentation on the Bf 109 and always backs up his words with that. I've no reason to believe he has the flight test report on that G-2 that easily made 666kph, especially as Soviet literature also mentions this plane test. The plane is question is identified and the Werknummer is known.
You on the other hand was just caught misrepresenting that '732 kph' datenblatt until you got exposed with it, and not very good at supporting your claims with documentations. You can't even give reference numbers, what's the panic, that someone will take the time, find the report and show it in it's completeness, unlike you who picks out parts of it to support his jihad?
You are the one who don't have the report, but deny that it exists.
As you have allready seen, the Mtt tested Bf 109G did 626 km/h at FTH 6100m with the 1,3ata and 2600rpm.[/B]
Uhum, a particular G-1 airframe where tests themselves note the engine problems of the DB 605 engine, probably faulty supercharger. Curious why you don't note that small isn't it, the
In the Erla set (13 planes), none of the planes reached 7000m FTH the average being 6700m and highest being 6900m (probably above spec rpm and/or below spec MAP).
gripen [/B]
You are welcome to share the details of those tests, so we can all see the conditions of those planes. A reference to your source would be the minimum. I must note that you have already exposed yourself with that little affair saying 'Mtt claiming 732kph in it's calculations,' when in fact it claimed 660kph (perfectly believable), and the one you cherry-picked was the factory's estimation of a non-standard, aerodynamically improved project. Basically there's no reason to believe you.
OK, if you want to put it that way. To give some idea about the issue, at 10 km the calculated speed for the G-1 (Ausführung) is 632 km/h, which is about the same performance as the prototype 109G-5/AS reached in flight tests with the DB 605 AS and high altitude propeller at same power setting (1,3 ata 2600 rpm).[/B]
Oh, geez, not that cheap demagog bs again...
The G-1 was a considerably lighter aircraft (this means a lot at high altitude) with much cleaner lines.
109G-1 weighted some 3047kg a TO, the G-5 weighted 3220kg or so.
Aerodynamically, the G-5 differed from the G-1 having the following extra drag items (speed penelty at SL):
non retractable tailwheel : -12 kph
13mm bulges : - 9kph
wing bulges, maybe 1-2 kph.
Alltogether 22-24 kph at sl, at 10 000m this is about 70% greater loss in speed! Or about 40 kph worth at 10km alt. Now is it a wonder the dirtier G-5/AS airframe even with it's better altitude engine needed a lot more power to get the same speed?
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I think the "Performance Statistic recorded by the General Luftzeugmeisters/C-E2 13 August and 1 November 1944" is flight data over several Airplanes (Statistic)!
And the 109G6/R2 Reconnaissance with DB605AM has nearly the same Performance like the 109G14 with DB605AM!
- Performance Statistic by GLZM August and November
Me109G6 with DB605A 1310PS - 0m, combat speed, 3196kg
0m 510km/h
6600m 630km/h
Me109G6 with DB605A 1475PS - 0m, emergency speed, 3196kg
0m 530km/h
6600m 640km/h
- Performance Statistic by GLZM August and November
Me109G6/R2 Reconnaissance with DB605AM 1240PS - 0m, combat speed, 3320kg
0m 498km/h
6600m 628km/h
Me109G6/R2 with DB605AM 1800PS - 0m, emergency speed, 3320kg
0m 569km/h
5000m 666km/h
- Performance Statistic by GLZM August and November
Me109G6AS with DB605AS 1275PS - 0m, combat speed, 3221kg
0m 500km/h
8800m 648km/h
Me109G6AS with DB605AS 1435PS - 0m, emergency speed, 3221kg
0m 520km/h
9000m 660km/h
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(http://img101.potato.com/img.php?loc=loc135&image=bca_Me109G6A_AM_AS_daten.jpg)
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Originally posted by Crumpp
What does performance of the production G-1 have to do with performance of the prototype G-5?
I compared calculated performance of the G-1 to the flight tested performance of the G-5/AS. If we compare flight tested performance of the G-1 to the flight tested performance of the G-5/AS, the later is over 50 km/h faster at 10000m at same power setting.
Originally posted by Kurfürst
Hate to point it out, but butch2k is without exception is a very credible and honest person, who has literally tons of documentation on the Bf 109 and always backs up his words with that.
Butch has noted that he had problems to undestand the cryptic content of the report.
Originally posted by Kurfürst
Uhum, a particular G-1 airframe where tests themselves note the engine problems of the DB 605 engine, probably faulty supercharger.
I can't find any note about faulty supercharger from the report? Based on "Gebläsedruck" curves supercharger actually seem to be give better than normal performance at low altitude. Speed at 10000m is very normal for a tested G-1 or G-2.
Originally posted by Kurfürst
You are welcome to share the details of those tests, so we can all see the conditions of those planes. A reference to your source would be the minimum.
It's from the NASM microfilms (I don't know which because I got these from other people), butch2k has a copy if you are interested. There is no details on tested planes but given the dates, these were probably G-1s.
Originally posted by Kurfürst
109G-1 weighted some 3047kg a TO, the G-5 weighted 3220kg or so.
The tested plane weighed 3190kg in take off and it was a AS airframe ie no mg bulges. It was some 50 km/h faster at 10000m than flight tested G-1s.
gripen
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I compared calculated performance of the G-1 to the flight tested performance of the G-5/AS. If we compare flight tested performance of the G-1 to the flight tested performance of the G-5/AS, the later is over 50 km/h faster at 10000m at same power setting.
It is an ignorant comparison for the reasons stated in my previous post.
It is impossible to determine the performance of one type of aircraft based off the prototype of another.
Look up the phrase, "rhetorical question" too BTW. It will keep you from looking like a complete idiot by answering the question.
http://www.wordreference.com/definition/rhetorical%20question
All the best,
Crumpp
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Originally posted by Crumpp
It is an ignorant comparison for the reasons stated in my previous post.
I can't follow your logic here, the flight tested difference between the series production G-1 and the G-5/AS prototype was over 50 km/h. The G-1 simply lacks the key features of the high altitude performance ie high altutitude propeller and the larger supercharger. Besides, the flight tested FTH of the G-5/AS was 8300m while the claimed FTH was 8800m, so the gap would have been even larger if it had done up to the claimed performance.
gripen
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I can't follow your logic here, the flight tested difference between the series production G-1 and the G-5/AS prototype was over 50 km/h. The G-1 simply lacks the key features of the high altitude performance ie high altutitude propeller and the larger supercharger. Besides, the flight tested FTH of the G-5/AS was 8300m while the claimed FTH was 8800m, so the gap would have been even larger if it had done up to the claimed performance.
This is why people put you on their ignore list, Gripen.
Seems to me, that sometimes when you cannot base your arguments on data, you revert to playing silly tricks with semantics.
Your comparison of:
OK, if you want to put it that way. To give some idea about the issue, at 10 km the calculated speed for the G-1 (Ausführung) is 632 km/h, which is about the same performance as the prototype 109G-5/AS reached in flight tests with the DB 605 AS and high altitude propeller at same power setting (1,3 ata 2600 rpm).
Is not a valid comparison for the simple fact the aircraft are different. One is a prototype with a much larger percentage speed range.
The data was valid or invalid as determined by Mtt for their prototype during the development of the Bf-109G5/AS. It would have been used or discarded in that program. That is what prototypes are for in the first place!
To turn around and use that data and compare it to performance estimates of completely different aircraft further compounds the margin of error even more.
You trying to make a judgment on the validity of Mtt's design estimates off of such an ignorant comparison it is just plain silly.
All the best,
Crumpp
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Originally posted by gripen
I compared calculated performance of the G-1 to the flight tested performance of the G-5/AS. If we compare flight tested performance of the G-1 to the flight tested performance of the G-5/AS, the later is over 50 km/h faster at 10000m at same power setting..
[/B]
You also ignore that there was significant drag and weight difference between the G-1 and G-5 models that explans why the G-5 needs more power than the G-1 to get the same speed. Unless you claim the G-1 and G-5 was aerodynamiccaly the same, which of course they were not. The G-5 had worser cowling, wing bulges, weighted some 100-150kg more, and most importantly, it had non-retractable tailwheel.
Some G-1 and G-2 test results for you at 10km, 1.3ata :
Rechlin's tested G-1, 640 kph.
NII VVS tested G-2, 645 kph.
Originally posted by gripen
Butch has noted that he had problems to undestand the cryptic content of the report.
[/B]
Curious, I can't remember that, but I can remember he had said it's a flight test, which is supported by Soviet literature itself, and to qoute Carl-Frederik Geust's "Under the Red Star" the NII VVS got 650 km/h @ 7000 m from a Me 109G-2/R6, and 16 - 19 km/h more from a clean Me 109G-2 (W.-Nr. 14513).
I can't find any note about faulty supercharger from the report?
To qoute you :
"the Mtt tested Bf 109G did 626 km/h at FTH 6100m with the 1,3ata and 2600rpm. In the Erla set (13 planes), none of the planes reached 7000m FTH the average being 6700m and highest being 6900m (probably above spec rpm and/or below spec MAP). "
Moreover, the single Mtt tested G-1's FTH in climb was only 5500m, whereas the DB605A's static FTH was already 5800m.
The report is about compared the DB 601E and the 605A at the same powersetting btw (1.3ata) in the same airframe.. The DB 605A relates in output to the 601E similiarly as the 605AS relates to the 605A (in which case gripen argues it should be 50kph faster in a worser airframe), ie. nominally 1200 PS vs 1310 PS at 1.3ata, and much better at altitude.
Still, curiously, when the SAME airframe was tested with 601E, it reached 621 kph at 6000m.
When tested with the 605A, it only improved to 626kph at 6200m.
According to gripen analogy with the G5/AS, it should have reached at least 4-50kph more than with the 601E. Oops, that's exactly the same value the Soviets, Rechlin measured in flight tests, and Mtt calculated.
Based on "Gebläsedruck" curves supercharger actually seem to be give better than normal performance at low altitude. ..
[/B]
I don't think you understand what Gebläsedruck means.
Speed at 10000m is very normal for a tested G-1 or G-2..
[/B]
What is 'normal'? How do you decide what is 'normal'?
No, it's much lower than tested G-1 or G-2 tested by the NII VVS, or Rechlin, or Mtt calculations, or the official Kennblatt that was issued to inform pilots about the plane's performance.
It's from the NASM microfilms (I don't know which because I got these from other people), butch2k has a copy if you are interested. There is no details on tested planes but given the dates, these were probably G-1s.
[/B]
'Some NASM microfilms' - that doesn't helps much others the get idea of the test conditions, gripen. And I won't bug butch because of your claims. If you wish the fill your statements with credibilty, make the report clearly identifiable, or post it, send it via email, etc. Or just post the relevant conditions.
The tested plane weighed 3190kg in take off and it was a AS airframe ie no mg bulges. [/B]
The AS cowling also had MG bulges gripen. That cowling was still draggier than the G-1, and the non-retractable tailwheel (G-1s was retractable)is still there, not to say 3190 kg weight vs. 3047 kg of the G-1.
All in all, the G-5 airframe is at least 30-40kph draggier than the G-1 airframe at 10km altitude. The AS engine only made up for that. It's doesn't needs to be explained why a draggier plane needs more power to get similiar speeds.
It was some 50 km/h faster at 10000m than flight tested G-1s.
gripen [/B]
Your not is not very good, gripen.
Ie. the flight tested G-1s speed at 10km :
Rechlin's tested G-1, 640 kph.
NII VVS tested G-2, 645 kph.
You say the G-5/as was some 50 km/h faster than this, it means it must have reached some 690kph at 10km. Impressive, for a 30-min rating.
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Kurfürst,
The Bf 109 G-1 Kennblatt data isn't corrected for compressibility. At 10 km TAS would be ~614 km/h.
This brings some questions about the soviet test, like what kind of performance reductions the soviets used or what were the conditions of the plane (manifold pressure reached, radiator flap position, etc).
Finally, you can get the sheet of Erla measurements (A/IV/64/43) from NASM Reel 2258, starting at Frame 430.
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Thanks for the reference, Porta. I`ll look into it.
As for the Soviet test, manifold pressure was 1,3ata as per butch2k, and indeed the Soviet climb curves are in very close agreement with finnish and Rechlin climb data at 1,3ata.
"The Bf 109 G-1 Kennblatt data isn't corrected for compressibility. At 10 km TAS would be ~614 km/h."
How did you confirm that? The last I checked the 1943 Kennblat does not note this, neither the (2 page of the )Rechlin paper I have. However ~614 does seem to make sense, if the compressibility notice is valid. It would comply well with the ~590kph claimed by those docs which are done with 109G with non retractable tailwheel. Given the -12kph penelty at SL (see Leistungzustammenstellung Me109G), it should be around 20kph at 10km... 614-20=595... :)
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The Kennblat gives both Va and Vw values, and you can cheek that Vw is just Va corrected for density changes. By the way, 640 Km/h @ 10 km is a typo, it should read 630 km/h.i
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about the 109G-14 speed
The 109G-14 speedgraph on this link http://www.spitfireperformance.com/spit14v109.html is the speeds we get on our AH 109G-14?
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Originally posted by 1K3
about the 109G-14 speed
The 109G-14 speedgraph on this link http://www.spitfireperformance.com/spit14v109.html is the speeds we get on our AH 109G-14?
Try reading the thread...
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The Bf 109 G-1 Kennblatt data isn't corrected for compressibility.
Correct.
The Kennblatt will show exactly what the pilot should read on the gauge.
The Luftwaffe used two different types of airspeed indicators, Fahrtmesser 22231 and Fahrtmesser 22234, in the FW190. Not sure whether both were used in the 109 series as well.
The allies did the same thing with their published data. The speed shown is the speed the pilot reads in the cockpit.
All the best,
Crumpp
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Originally posted by Crumpp
...Fahrtmesser ...Fahrtmesser...
L0loLOLol0LOloL0loLOLol0LOl0L 0loLOLol0LOlOL0loLOLol0LOlOL0 loLOLol0LOl
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Grow *snicker* up, debonair, they're *giggle* posting perfect *snort* legitimate words here *snicker*
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Originally posted by Crumpp
This is why people put you on their ignore list, Gripen.
You can also do that if you don't like my postings.
Originally posted by Crumpp
Is not a valid comparison for the simple fact the aircraft are different. One is a prototype with a much larger percentage speed range.
It's up to you prove that the G-5/AS data is not valid. Using the data for the basicly similar G-6/AS posted by elkaskone, the claimed speed at 9000m is 660km/h while the tested G-5/AS did about 647km/h ie well within 3% tolerance.
Comparing the test data from Mtt and FAF for production G-1 and G-2 to the Mtt calculation gives more than 50km/h difference ie far above 3% tolerance.
Originally posted by Kurfürst
Some G-1 and G-2 test results for you at 10km, 1.3ata :
Rechlin's tested G-1, 640 kph.
NII VVS tested G-2, 645 kph.
So far no one has come up with the verifyable documentation that these are really flight tested values. Normal flight tested values at 10000m for the Bf 109G with the DB 605A are around 550-580 km/h (as an example Mtt and FAF data which you have).
Originally posted by Kurfürst
All in all, the G-5 airframe is at least 30-40kph draggier than the G-1 airframe at 10km altitude. The AS engine only made up for that. It's doesn't needs to be explained why a draggier plane needs more power to get similiar speeds.
Simply looking the low altitude speed values of the tested planes, the drag difference is less than 20km/h and the AS had roughly 200ps more available at 10000m and a better propeller for high altitude.
Originally posted by Kurfürst
I don't think you understand what Gebläsedruck means.
Please explain.
gripen
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Originally posted by gripen
Comparing the test data from Mtt and FAF for production G-1 and G-2 to the Mtt calculation gives more than 50km/h difference ie far above 3% tolerance.
[/B]
Different plane conditions, apples and oranges.
Tests done by Rechlin and NII VVS perfectly match Mtts calculations.
So far no one has come up with the verifyable documentation that these are really flight tested values.
[/B]
Nope, it's only you who deny the existence of these test flights, despite several sources veryfying that fact and identifying the plane themselves.
It's up to you to prove your claims that those tests weren't... err, tests.
Normal flight tested values at 10000m for the Bf 109G with the DB 605A are around 550-580 km/h (as an example Mtt and FAF data which you have).
[/B]
Just a little more sweating gripen, and you can made the 109G slower than the 109E. The Mtt data was done with a plane that had some kind of trouble with it's engines altitude output. You know that very well.
Simply looking the low altitude speed values of the tested planes, the drag difference is less than 20km/h and the AS had roughly 200ps more available at 10000m and a better propeller for high altitude.
[/B]
Well let's see.
A plane does 520 kph at SL with 1310 PS, and another 500 kph with the same power.
We want to make the 2nd plane just as fast as the 1st plane. The speed difference is 20kph, or 4%. The power requirement increases on the cube :
Speed difference : 520 / 500 = 1.04
Power required to get 500 to 520 : 1.04^3 = 1.125, or 12.5% more power required. 1310 x 1.125 = 1473 PS. Or an extra 131 PS.
Summary : For the 20kph (assumed true for the example ) draggier G-5 to get the same speed as the G-1, 131 PS extra power is required.
One can see very well why is there not much of a surprise to see why the draggier aircraft isn't that much faster than the cleaner one, despite more power.
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It's up to you prove that the G-5/AS data is not valid.
Gripen,
Please point out where anyone claimed the Bf-109G5/AS data was not valid?
It is a new type testing and has a much larger percentage of error.
What was said is:
The data was valid or invalid as determined by Mtt for their prototype during the development of the Bf-109G5/AS. It would have been used or discarded in that program. That is what prototypes are for in the first place!
What's invalid and ignorant is your attempting to draw conclusions about the accuracy of Mtt calculations by comparing the Bf-109G1 production machine calculations and the flight test of a Bf-109G6/AS prototype.
Comparing the test data from Mtt and FAF for production G-1 and G-2 to the Mtt calculation gives more than 50km/h difference ie far above 3% tolerance.
BTW Gripen, VDM 9-12159 on WNr 26108 is the standard Bf-109G VDM propeller for GM-1 installation.
All the best,
Crumpp
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Originally posted by Kurfürst
Different plane conditions, apples and oranges.
No, these flight tested planes were standard production G-1s and G-2s as claimed for the Mtt calculation.
Originally posted by Kurfürst
Tests done by Rechlin and NII VVS perfectly match Mtts calculations.
So far no one has come up with the verifyable documentation that these are really flight tested values. To put it simple: No documentation, no proof.
Originally posted by Kurfürst
The Mtt data was done with a plane that had some kind of trouble with it's engines altitude output.
There is no claim about problems with supercharger in the report. The reached FTH is quite typical for summer time testing and within normal variation as given in the Erla set.
Originally posted by Kurfürst
A plane does 520 kph at SL with 1310 PS, and another 500 kph with the same power...
The tested G-5/AS did 507km/h at 0m with about 35ps less than the Mtt tested G-1 which did same speed. The MT-215 did 523km/h and the reference G-5 did 506km/h at same power setting. And this tells nothing about efficiency differences in the propeller efficiency at high altitude.
Originally posted by Crumpp
Please point out where anyone claimed the Bf-109G5/AS data was not valid?
Your post 11-19-2005 02:22 PM:
"Is not a valid comparison for the simple fact the aircraft are different. One is a prototype with a much larger percentage speed range."
The G-5/AS performance data (prototype) is well within 3% variation claimed for the AS type type aircraft.
Originally posted by Crumpp
What's invalid and ignorant is your attempting to draw conclusions about the accuracy of Mtt calculations by comparing the Bf-109G1 production machine calculations and the flight test of a Bf-109G6/AS prototype.
It's fully valid showing the tested performance of the specialized high altitude aircraft with high altitude engine and propeller compared to the calculated performance of standard aircraft with standard engine and propeller.
gripen
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Originally posted by gripen
So far no one has come up with the verifyable documentation that these are really flight tested values. To put it simple: No documentation, no proof.
I'd express it more precisly :
Gripen so far no one has come up with the verifyable documentation about these claims of his. To put it simple: No documentation, no proof - just of obviously biased zealotry.
And since you started your claims with a lie about the true conditions of the Mtt datenblatt, and you are very selective which tests, regardless of the noted conditions, are to be worshipped, and which are to be neglected and dismissed, which happen to be the ones that disprove your claims, I think we can just safely ignore all what you say. I don't even see a danger of someone actually believing that cr@p, it's that much in-credible.
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Try understanding what you read, Gripen. If you have questions please ask. However once again your assumptions are killing you.
is not a valid comparison for the simple fact the aircraft are different. One is a prototype with a much larger percentage speed range."
Nothing in that sentence says anything about the Bf-109G5/AS protoype data not being valid for Bf-109G5/AS develpment. IN fact the report recommends further development of the DB605AS.
That sentence says your comparision is not valid.
It's fully valid showing the tested performance of the specialized high altitude aircraft with high altitude engine and propeller compared to the calculated performance of standard aircraft with standard engine and propeller.
Now your adding to the ignorance. Changing to a generally more efficient prop does not necessarily mean a level speed increase. For example, flight testing the wide chord wooden prop on the FW190A showed a drop in level speed but greatly increased climb.
Just changing propellers on the same aircraft can have a dramatic effect on speed. Here in this flight test, we see the variation in speed at a given altitude of the exact same aircraft flown with 5 different propellers:
(http://img13.potato.com/loc253/th_db7_Props.jpg) (http://img13.potato.com/img.php?loc=loc253&image=db7_Props.jpg)
You simply do not have enough data on the propeller to make the kind of sweeping judgement your trying to conclude.
You are attempting to draw general conclusions about Mtt's performance estimate accuracy based off standard production estimates of one variant by cross checking it with flight tested information from a completely different variants prototype.
A comparision which is ignorant.
All the best,
Crumpp
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Some note on the propellors, I possess some flight testing results for the 109K with four different propellors mounted, including the 12087 of the early 109G, and the 12159 of the high alt engines 109G/Ks, like the G-5/AS. There was also more advanced forms of these two tested.
The speed difference between the 4 props was rather minimal, 5-10 kph max between the best and worst, on the same airplane.
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Rather close to the max speed specs of other props I have seen Kuffie.
Sometimes, climb rate would be affected more I belive.
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Originally posted by Kurfürst
And since you started your claims with a lie about the true conditions of the Mtt datenblatt, and you are very selective which tests, regardless of the noted conditions, are to be worshipped, and which are to be neglected and dismissed, which happen to be the ones that disprove your claims, I think we can just safely ignore all what you say. I don't even see a danger of someone actually believing that cr@p, it's that much in-credible.
Hm... the Mtt data sheets are open for everyone to check out what I have claimed in this thread as well as the tests I have quoted.
BTW you have announced to ignore me earlier too.
Originally posted by Crumpp
That sentence says your comparision is not valid.
The prototype G-5/AS values are within less than 3% of claimed speed of the AS.
Originally posted by Crumpp
Changing to a generally more efficient prop does not necessarily mean a level speed increase.
The propeller of the AS ie the 12159 is a high altitude propeller and 10000m is high altitude.
gripen
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The prototype G-5/AS values are within less than 3% of claimed speed of the AS.
Which has nothing to do with you original contention that a conclusion can be drawn from comparing them with Bf-109G1 performance estimates.
No one is denying that the Bf-109G5/AS data is valid for the prototype Bf-109G5/AS. You’re like a scratched record. This is the third time I have had to repeat that.
The propeller of the AS ie the 12159 is a high altitude propeller and 10000m is high altitude.
True, 10,000M is very high and VDW 12159 is supposed to be a high altitude propeller.
Other nice to know information that has nothing to do with your comparision is submarines can dive deep in the ocean and the ocean is very deep.
:confused:
What does any of this have to do with the your ignorant comparision of the Bf-109G1 performance estimates and flight testing of the Bf-109G5/AS prototype??
All the best,
Crumpp
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Originally posted by Crumpp
What does any of this have to do with the your ignorant comparision of the Bf-109G1 performance estimates and flight testing of the Bf-109G5/AS prototype??
It's a fully valid comparison showing that calculated performance of the G-1 is at same class with the flight tested AS at 10000m. In the flight tests of the production G-1 and mostly similar G-2, the results at 10000m were more than 50km/h below the calculated values ie the difference is far over 3%.
gripen
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It's a fully valid comparison showing that calculated performance of the G-1 is at same class with the flight tested AS at 10000m. In the flight tests of the production G-1 and mostly similar G-2, the results at 10000m were more than 50km/h below the calculated values ie the difference is far over 3%.
I don't see any Bf-109G1 production machine performance estimates posted in this thread to compare with production Bf-109G1 flight test results.
Nor do I see any Bf-109G5/AS prototype performance estimates to compare with the prototype flight test results.
All I see your conclusions based on an ignorant assumption.
All the best,
Crumpp
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I don't really understand why there is this drive in some people to make their oposition fighter out to be as crappy as possible, cherry picking the data to make it look just so.
Yes, there are examples of poor performing airframes of just about all fighters, but to hold the low end up as the normal performance level seems very biased and suspect.
Cherry picking data to match a preconcieved bias is just poor research methodology.
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Originally posted by Crumpp
I don't see any Bf-109G1 production machine performance estimates posted in this thread to compare with production Bf-109G1 flight test results.
Available from NASM as pointed out by Mr. Porta.
Originally posted by Crumpp
Nor do I see any Bf-109G5/AS prototype performance estimates to compare with the prototype flight test results.
The G6/AS (data posted by Mr. elkaskone) is basicly the same as the G5/AS.
gripen
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Originally posted by Karnak
I don't really understand why there is this drive in some people to make their oposition fighter out to be as crappy as possible, cherry picking the data to make it look just so.
I don't know if you mean me but lets have a look to the data.
The flight test data for the G-1 is from Mtt test (ie manufacturer) and this data was used as reference in Mtt documentation.
The MT-215 test data (a basicly similar G-2) is from the FAF tests of a new plane in the squadron service and the results are actually somewhat better than Mtt measurements specially at low altitude (mostly due to colder conditions). There is much worse data available if somebody cares to search a bit.
If we compare these measurements to the AH G-2 at 30k (military power):
AH G-2 about 600 km/h
Mtt G-1about 600 km/h
MT-215 about 595 km/h (slightly below spec rpm)
So the flight tests give same kind of performance as the AH G-2, so apparently I'm making the Bf 109G-1 or G-2 to look just as good as it is in the AH. As for comparison the Mtt calculation for the G-1 (Ausführung) gives a bit over 640km/h at same altitude and the calculation for the Endzustand gives something over 670km/h (673km/h at 10000m).
Note that these tests are open for anyone to check out: Mtt G-1 data is available from the NASM (as well as Mtt calculations and G-5/AS test data) and MT-215 data is available from the Hallinportti Ilmailumuseo (an aviation museum in Finland) and Sota-arkisto (Finnish war archives). In addition many members of the this BBS have this data allready.
Overall this has quite little to do with the performance of the G-14 with MW-50, I can say that the performance given in the Mtt datasheet is marked as calculation and I have no idea if it is realistic. And the official AH data is not yet avalable so there is not much to discuss about.
gripen
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Sure gripen, and all the other flight tests are conviniently ignored by you, pointing a test by Mtt with a DB605 engine that obviously had problems, bringing only marginal (6km/h) speed increase to the 601E 'despite having 200 more HP and a better high altitude propeller', and a Finnish flight test that was done with a draggier version of the 109G-2, ie. photographs of the test MT 215 shows the aircraft had non-retractable tailwheel which unlike most G-1s and G-2s. This was responsible for -20 kph speed loss at alttiude, which curiously would just bring the MT 215 to the level of the other tested aircraft by Rechlin and NII VVS.
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Originally posted by Kurfürst
Mtt with a DB605 engine that obviously had problems, bringing only marginal (6km/h) speed increase to the 601E 'despite having 200 more HP.
The output difference between the DB 605A and the DD 601E is between 50-110PS depending on RAM with given ratings. There is no particular problems mentioned in the report. The coolers were more open with the DB605A causing some drag penalty.
Originally posted by Kurfürst
and a better high altitude propeller',
The propellers used for the tests seem to be standard propellers; the 12010 for the DB 601E and the 12087 for the DB 605A. There is no reason to believe that there was large differences in the efficiency.
Originally posted by Kurfürst
and a Finnish flight test that was done with a draggier version of the 109G-2, ie. photographs of the test MT 215 shows the aircraft had non-retractable tailwheel which unlike most G-1s and G-2s.
Actually most of the Finnish G-2s had a fixed tailwheel when delivered and all G-1s and G-2s got sooner or later fixed tail wheel.
Originally posted by Kurfürst
This was responsible for -20 kph speed loss at alttiude.
According to Raunio and Hörner, the loss was around 10km/h at altitude. And the MT-215 (slightly below spec rpm) did actually roughly 560km/h at 10000m ie about 20km/h less than the Mtt tested G-1.
gripen
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Well, according to the Janes I have, the G-14 could have any number DB605 power plants. Janes lists the DB605 A, AM, AS, ASB, ASM, and D engines as all having been fitted to the G-14, with either MW50 or GM1 power boosting equipment depending upon the exact subtype.
I'll post some of the relavant specs from the engines section below:
DB605 AM: 1,800hp at 2800rpm @ sea level (1.7 ata)
DB605 AM: 1,700hp at 2800rpm @ 13,500 ft (1.7 ata)
DB605 AS: 1,435hp at 2800rpm @ sea level (1.42 ata)
DB605 AS: 1,200hp at 2800rpm @ 26,200 ft (1.42 ata)
I don't know why Janes doesn't have them tested at the same boost pressure, but that's the specs the list for those.
The D engine apparently has 2 subtypes - DB and DC
DB is 8.3:1 compression running 87 Octane and the MW50 system
DC is 8.5:1 compression running 96 Octane and the MW50 system
DB605DB: 1,800hp at 2,800rpm @ sea level (1.8 ata)
DB605DB: 1,530hp at 2,800rpm @ 19,600 ft (1.8 ata)
DB605DC: 2,000hp at 2,800rpm @ sea level (1.98 ata)
DB605DC: 1,800hp at 2,800rpm @ 16,700 ft (1.98 ata)
The DB605DC looks to be the best version of the motor, which tells me that isn't the one that is in the G-14! The 109K4 is listed in Janes only with the DB605D series motors, so there is some hope that we at least have the best power plant in that.
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Originally posted by EagleDNY
Well, according to the Janes I have, the G-14 could have any number DB605 power plants. Janes lists the DB605 A, AM, AS, ASB, ASM, and D engines as all having been fitted to the G-14, with either MW50 or GM1 power boosting equipment depending upon the exact subtype.
I'll post some of the relavant specs from the engines section below:
DB605 AM: 1,800hp at 2800rpm @ sea level (1.7 ata)
DB605 AM: 1,700hp at 2800rpm @ 13,500 ft (1.7 ata)
DB605 AS: 1,435hp at 2800rpm @ sea level (1.42 ata)
DB605 AS: 1,200hp at 2800rpm @ 26,200 ft (1.42 ata)
I don't know why Janes doesn't have them tested at the same boost pressure, but that's the specs the list for those.
The D engine apparently has 2 subtypes - DB and DC
DB is 8.3:1 compression running 87 Octane and the MW50 system
DC is 8.5:1 compression running 96 Octane and the MW50 system
DB605DB: 1,800hp at 2,800rpm @ sea level (1.8 ata)
DB605DB: 1,530hp at 2,800rpm @ 19,600 ft (1.8 ata)
DB605DC: 2,000hp at 2,800rpm @ sea level (1.98 ata)
DB605DC: 1,800hp at 2,800rpm @ 16,700 ft (1.98 ata)
The DB605DC looks to be the best version of the motor, which tells me that isn't the one that is in the G-14! The 109K4 is listed in Janes only with the DB605D series motors, so there is some hope that we at least have the best power plant in that.
The G-14 in AH has the DB605AM. All it is is a G-6 (DB605A) with MW-50 (DB605AM = M = MW-50). All MW-50 does is cool the charge and allow for higher boost by preventing the fuel from detontating.
The other engine the G-14 had was the DB605ASM. The 'AS' indicates that this DB605A(M) is fitted with the larger supercharger of the DB603. This gave a higher FTH and better performance up high.
The DB605D was fitted on the G-10 and the K-4. It too had the DB603 supercharger and MW-50. The C and B indicate the fuel type. For example a DB605DC ran on C-3 fuel, a DB605B ran on B-4 fuel.
A K-4/G-10 running at 1.98ata rquired C-3 + MW-50 and was only available late in the war (I will let others argue over when and how many) but most G-10 and K-4s did not run at 1.98ata.
In AH the K-4 has a DB605DB. (B-4 + MW-50)
Also GM-1 was never serialized on the late 109s. It provide a performance boost 2000m or so above FTH. With the larger DB603 supercharger 109s high alt performance was sufficient.
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German spec sheets on the DB605s
http://mitglied.lycos.de/luftwaffe1/aircraft/lw/DB605_varianten.pdf
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Thanks for the note on the fuel codes - I knew they had 87 & 96 octane, I just didn't know their name for it.
I personally would like to see a 109 variant utilizing the DC605DC - maybe we can talk HT into making the K-6 available. My Janes is showing that as having an additional 2 30mm gondolas (103's not 108's) and IMHO that with the DB605DC powerplant would make a good "slightly perked" 109 variant. I'm sure it would cause some "brown trousers" in the bombing ranks.
I myself am still testing out the various types - frankly, I'm having plenty of luck perk-farming with the G-2. It seems like so many folks are used to fighting the rocket-sled 109s they forget that there are a few varieties that can hang in a turn-fight.
EagleDNY
;)
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Actually most of the Finnish G-2s had a fixed tailwheel when delivered
There were some other differences too, Gripen in the Finnish 109's. Can you say "export" version?? No country in the world has ever sold their best equipment to another nation in Tier 1 condition.
All the best,
Crumpp
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K-6 had a new wing with 2 built in Mk-108 (not 103 :) ), but didn't make it in time before the end of the war
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Originally posted by EagleDNY
Thanks for the note on the fuel codes - I knew they had 87 & 96 octane, I just didn't know their name for it.
I personally would like to see a 109 variant utilizing the DC605DC - maybe we can talk HT into making the K-6 available. My Janes is showing that as having an additional 2 30mm gondolas (103's not 108's) and IMHO that with the DB605DC powerplant would make a good "slightly perked" 109 variant. I'm sure it would cause some "brown trousers" in the bombing ranks.
;)
Agreed, a perked 109 with the DC engine would be nice. The DC was mounted from January 1945 onwards into the 109G-10 and K-4, and a very similiar (identical in output, ie.2000 HP) engine, the DB 605 ASC was put into the 109 G-14/AS. Output was 2000 PS at 1.98ata manifold pressure, which was cleared for service use after trials in late February. There's written documentation from 20th March 1945 for 1.98ata use for the 109Ks/G-10s of four Luftwaffe wings, ie. II and III of JG 27, and III and IV Gruppe of JG 53, altogether possessing ca 150 planes at that time. See my site for details!
At 1.98ata, the 109K did 607 kph at SL, 715 kph at 6000m, initial climb rate was 24.5-25 m/sec.
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Hi, gripen and everyone
Yes, Russians tested Bf109G-2. Pls see below results of test in NII VVS.
I also have a speed curve, but do not know how to attach it to this message
Altitude TAS (km/h) Vertical speed Climb time
m/sec min
G-2/R6 G-2 G-2/R6 G-2 G-2/R6 G-2
0 505 524 16,8 19 0 0
1000 535 554 17,8 20,2 1,0 0,8
2000 564 582 18,3 21,0 1,9 1,7
3000 586 602 16,2 18,9 2,8 2,6
4000 592 608 16,7 17,5 3,9 3,5
5000 593 610 13,9 16,6 5,1 4,4
6000 621 640 13,4 15,9 6,3 5.4
7000 650 666 11,0 13,2 7,7 6,5
8000 643 660 8,4 10,6 9,4 7,9
9000 630 648 6,0 8,0 11,7 9,8
10000 603 624 3,5 5,3 15,4 12,3
Dear ALL
I'm collecting German original tests of Luftwaffe aircrafts
I found some data charts on this forum.
Maybe somebody can add anything new from GL/CE-2 or something like this.
I can exchange for data of Russian aircrafts (Yak, etc.)
BRGS
George
Originally posted by gripen
At least in my scale calling some one's actions arrogant is quite personal.
As noted above in the same data set there is exactly same speed values for the G-14 dated 13.8.1944 and marked as Rechnung just like all other values from the same date.
(http://img106.potato.com/loc169/th_69e_rechn.jpg) (http://img106.potato.com/img.php?loc=loc169&image=69e_rechn.jpg)
Did the Russians actually do the full speed tests?
gripen
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Sorry for such format
The order of shown numbers is following:
Altitude, m
TAS, km/h (both fop G-2/R6 and G-2)
Vertical speed m/sec (both fop G-2/R6 and G-2)
Climb time, min (both fop G-2/R6 and G-2)
BRGS
Originally posted by George
Hi, gripen and everyone
Yes, Russians tested Bf109G-2. Pls see below results of test in NII VVS.
I also have a speed curve, but do not know how to attach it to this message
Altitude TAS (km/h) Vertical speed Climb time
m/sec min
G-2/R6 G-2 G-2/R6 G-2 G-2/R6 G-2
0 505 524 16,8 19 0 0
1000 535 554 17,8 20,2 1,0 0,8
2000 564 582 18,3 21,0 1,9 1,7
3000 586 602 16,2 18,9 2,8 2,6
4000 592 608 16,7 17,5 3,9 3,5
5000 593 610 13,9 16,6 5,1 4,4
6000 621 640 13,4 15,9 6,3 5.4
7000 650 666 11,0 13,2 7,7 6,5
8000 643 660 8,4 10,6 9,4 7,9
9000 630 648 6,0 8,0 11,7 9,8
10000 603 624 3,5 5,3 15,4 12,3
Dear ALL
I'm collecting German original tests of Luftwaffe aircrafts
I found some data charts on this forum.
Maybe somebody can add anything new from GL/CE-2 or something like this.
I can exchange for data of Russian aircrafts (Yak, etc.)
BRGS
George