Aces High Bulletin Board
General Forums => Aircraft and Vehicles => Topic started by: Furball on December 14, 2003, 11:56:50 AM
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im fed up of all the p38 threads, f4u, p51 etc etc etc threads so im starting my own. Fix the Spitfire 14, Spitfire IX and Mosquito!
TACTICAL COMPARISON WITH SPITFIRE IX
13. The tactical differences are caused chiefly by the fact that the Spitfire XIV has an engine of greater capacity and is the heavier aircraft (weighing 8,400 lbs. against 7,480 lbs. of Spitfire IX).
Range & Endurance
14. The Spitfire XIV, without a long-range tank, carries 110 gallons of fuel and 9 gallons of oil. When handled similarily, the Spitfire XIV uses fuel at about 1 1/4 times the rate of the Spitfire IX. Its endurance is therefore slightly less. Owing to its higher speed for corresponding engine settings, its range is about equal. For the same reasons, extra fuel carried in a long-range tank keeps its range about equal to that of the Spitfire IX, its endurance being slightly less.
Speeds
15. At all heights the Spitfire XIV is 30-35 mph faster in level flight. The best performance heights are similar, being just below 15,000 and between 25,000 and 32,000 ft.
Climb
16. The Spitfire XIV has a slightly better maximum climb than the Spitfire IX, having the best maximum rate of climb yet seen at this Unit. The In the zoom climb the Spitfire XIV gains slightly all the way, especially if full throttle is used in the climb.
Dive
17. The Spitfire XIV will pull away from the Spitfire IX in a dive.
Turning Circle
18. The turning circles of both aircraft are identical. The Spitfire XIV appears to turn slightly better to port than it does to starbord. The warning of an approaching high speed stall is less pronounced in the case of the Spitfire Mk XIV.
Rate of Roll
19. Rate of roll is very much the same.
Search View and Rear View
20. The search view from the pilot's cockpit is good; the longer nose of the aircraft interferes with the all-round visibility, which remains the same as that of the Spitfire IX. Rear View is similar.
Sighting View and Fire Power
21. The sighting view is slightly better being 4 deg (140 m.p.h.) as against 3 1/3 deg. The two bulges at the side cause little restriction. The firepower is identical with the Spitfire IX.
Armour
22. As for the Spitfire IX
Conclusions
23. The all-round performance of the Spitfire XIV is better than the Spitfire IX at all heights. In level flight it is 25-35 m.p.h. faster and has a correspondingly greater rate of climb. Its manoeuvrability is as good as a Spitfire IX. It is easy to fly but should be handled with care when taxying and taking off.
(http://www.onpoi.net/ah/pics/users/ah_71_1071342328.jpg)
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So you're saying Spitfire MkIX should be made turn worse so it has an identical turning circle with MkXIV?
// fats
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LOL fats :D
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Climb
16. The Spitfire XIV has a slightly better maximum climb than the Spitfire IX, having the best maximum rate of climb yet seen at this Unit. The In the zoom climb the Spitfire XIV gains slightly all the way, especially if full throttle is used in the climb.
Yes there is something very wrong with the Spit14. :D
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Good call GScholz. Damn, the XIV is really porked, thanks for bringing this to our attention Furball!
HTC, we need to have the FM's drastically altered in the SpitIX and SpitXIV. The SpitIX turning radius should be greatly increased, and the SpitXIV should have a greatly reduced climb rate and much less lenient stall characteristics. I suggest the IX change should be made immediately since it is flown so often.
:D
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(http://www.fourthfightergroup.com/eagles/jf319climb.gif)
Notice with radiator flaps open.. :p
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That the Spit14?
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Never mind, it must be with a T/O weight of 8400 lbs. That chart shows that the AH Spit14 is grossly over modelled in climb.
(http://www.hitechcreations.com/ahhelp/models/charts/spit14climb.gif)
The AH Spit14 holds it's climb rate way better as altitude increases compared to your chart.
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Originally posted by Furball
Notice with radiator flaps open.. :p
That's why you have radiator flaps. During climbing you need maximum cooling because the airspeed (i.e. cooling effect) is low. During cruise you can close the flaps to reduce drag and keep the engine at best operating temp.
All WWII fighters climb with open radiators.
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The chart Furball posted is for the prototype Spit XIV. It had a lower gearing for the first supercharger gear, thus a lower critical alt in low gear.
Whereas the prototype had a critical alt at climbing speed of just under 2000ft, the production version had a critical alt of just under 10,000ft. See the CENTRAL FIGHTER ESTABLISHMENT
REPORT No. 78 at
http://www.fourthfightergroup.com/eagles/spit14pt.html
AH seems to have gone somewhere in the middle, with a climb rate and critical alt between the production and prototype versions.
Climb
16. The Spitfire XIV has a slightly better maximum climb than the Spitfire IX, having the best maximum rate of climb yet seen at this Unit. The In the zoom climb the Spitfire XIV gains slightly all the way, especially if full throttle is used in the climb.
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Yes there is something very wrong with the Spit14.
Bear in mind the A&AEE were comparing the Spitfire XIV with the Spitfire LF IX, with Merlin 66, that had a climb rate of 4,700ft/min. ie, the major production variant of the Spit IX (4000+ produced).
Not comparing it against the AH Spit IX, which is an early F IX, with Merlin 61, climb rate 3,900 ft/min (350 produced)
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Still not right.
Max. rate of climb in MS supercharger gear 5,040 ft/min. at 2,100 ft.
The AH Spit14 holds 5000 fpm up to 8-9k.
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Originally posted by GScholz
Yes there is something very wrong with the Spit14. :D
That's because we have a Spitfire F.Mk IX with a Merlin 61, not a Spitfire LF.Mk IX with a Merlin 66 in AH. They were testing it against the LF.IX.
Or are you under the impression that a Spitfire Mk IX is a Spitfire Mk IX is a Spitfire Mk IX?
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You did notice the :D didn't you? ;)
Still ... I haven't seen any data that justifies the 5000 fpm climb rate up to 8-9k for the Spit14.
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1. Introduction.
...........Climb and level speed performance and position error measurements have been made on Spitfire F Mk.VIII (Conversion) JF.319, the prototype Mk.XIV. This aircraft was fitted with a Griffon RG5SM engine and a 5-bladed Rotol propeller. It is understood that the final version of the Mk.XIV will have a Griffon 65 engine which differs from the engine now installed in having a higher MS supercharger gear ratio. The external features of this aircraft were similar to the production version of the Mk.XIV, except that the shape of the fin and rudder will probably be different.
Maybe thats it?
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A fully loaded Spit XIV of production line will climb to 20K in 5 minutes smooth. In AH it takes close to 6 minutes, so the XIV is porked in that way.
It also turns worse than the Spit IX, and stalls worse as well.
And for GSchlozie: A Spit 9 is about a Spit 9 as 109G is a 109G:D
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Originally posted by Angus
And for GSchlozie: A Spit 9 is about a Spit 9 as 109G is a 109G:D
Don't ya love it :)
Lets see regarding Spit IX variants:
LFIX with Merlin 66 engine
-C wing
-E wing
-Clipped wing
-normal span wing
-Small rudder
-Pointed larger rudder
-no trop filter
-trop filter
FIX Merlin 61, 63, 63A
-C wing
-E wing
-Clipped wing
-normal span wing
-Small rudder
-Pointed larger rudder
-no trop filter
-trop filter
HFIX Merlin 70
-C wing
-E wing
-extended wing
-normal span wing
-Small rudder
-Pointed larger rudder
-no trop filter
-trop filter
Just a few different kinds to choose from don't ya think? :)
Dan/Slack
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ooo ooo pick my x-mas present.....
ill have a...
L.F. IX with Merlin 66 engine
with... universal wing with 4 hispano option (we SHOULD already have this on our IX/XIV)
Clipped ...
Pointed rudder ...
no tropical filter please!
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Originally posted by Furball
ooo ooo pick my x-mas present.....
ill have a...
L.F. IX with Merlin 66 engine
with... universal wing with 4 hispano option (we SHOULD already have this on our IX/XIV)
Clipped ...
Pointed rudder ...
no tropical filter please!
They rarely used the 4 cannon armament. I've seen it on some ground attack Spit Vcs in Italy and on a RAAF Spit VIII
With the other stuff you want, the tropical filter would have been standard. Not the big Vokes filter of the V but the one that you can see on all the restored Spit IXs.
I'm with you though, Clipped wing LFIXe with broad chord rudder and Merlin 66. Better low alt performance, roll rate etc. We've got how many G model 109s? Seems like we could get an LFIXe too don't ya think? :)
Dan/Slack
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Tested some climbers offline, just for fun....
Spit XIV, no wep, full load, with takeoff roll, 20K 6:46 Spit XIV, w. WEP, full load. with takeoff roll, 20K 5:50
in Real life this should be about 5 minutes, no WEP mentioned.
So the Spit XIV is definately porked. It actually gets outclimbed by the AH 109G2!
109G2 no WEP, full load,no gonds, with takeoff roll. 20K 6:34 109G2 w. WEP, full load,no gonds, with takeoff roll, 20K 5:48
Going to Spit I, AH SpitI climbs too well for the old wooden airscrew, but way too slow for the Rotol airscrew. And we are talking about the 87 oct fuel in that sense. Could it be that the AH SpitI is a two blade plane with 100 octs? Don't know really.
At least far from being the best Spit mounted in the BoB.
On the other side, the 109E4 seems about correct, - the test flight numbers match the 109E4 in AH running without WEP
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:rofl :rofl :rofl
:aok
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Originally posted by Nashwan
The chart Furball posted is for the prototype Spit XIV. It had a lower gearing for the first supercharger gear, thus a lower critical alt in low gear.
... and ~200 more power this way in first gear. The AH spit has the power of a ~2000hp Griffon in 1st gear, and holds it up to 9k...
Just to make it clear
(http://www.mitglied.lycos.de/luftwaffe2/stuff/spit14_climb_ca9k.gif)
niklas
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Bahh.
Our AH Spit XIV is one minute (at least) slower that a production type Spitfire up to 20K. That is a fact!
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just ran some climb comparisions off line . . . nothing new but here's the skinny on the spit14, g10, and la7. but first the spit 14. and yes, i have utterly too too much time on my hands:)
1) 0 alt, 100% fuel, 50 cals- timed from wheels ups with wep on until it burns out: 1 min = 3,500 ft. 10k: 2:31. & 20k 5:30.
1a) this time plane leveled on deck and began climb at end of runway instead of prior to tower when plane normally begings climbing, same loadout. 1 min = 5,100. 10k: 2:40. 15k: 3:21, & 20k 4:48.
1b) kept end of runway take off since the #'s were better especially climb after 1 min, and changed to 303's instead of 50 cals. 1 min = 5,150. 10k: 2:02. 15k: 3:18. 20k: 4:53.
so comparing best (303's taking off at end of runway) to worst (50 cals taking off when plane lifts) heres the #'s:
1 min = 5,150 ft vs 3,500 ft.
10k: 2:02 vs 2:31.
15k: 3:18 vs 3:49
20k: 4:53 vs 5:30.
here's the g10#'s taking off at end of runway with 20mm and no junk on her, 100% fuel.
1 min = 4,800 ft. 10k: 2:08. 15k: 3:21. 20k: 4:43.
now side by side spit w/303's being first both planes wepping from beginning and taking off at runway's end.
1 min 5,150 vs 4,800 ft
10k: 2:02 vs 2:08
15k: 3:18 vs 3:21
20k: 4:53 vs 4: 43
for another point of reference, here's the la7-w/20mm (just figure the 30mm's will be worse prob should of used that loadout but wanted to keep things as light as possible).
1 min 4,800 ft. 10k 2:30. 15k: 4:16. 20k: 6:14.
as to what to make of it all . . . some things i knew but couldn't verify. 1) autoclimbing out isn't as effective as going level then autoclimbing at end of runway (or when plane is at default climb speed i guess). 2) i didn't know the 1400 rds of 303 weighed less--or weighs less in aces high. 3) didn't know g10 would outclimb spit14 to 20k.
btw, fuel load does matter. ran the very first test with spit 14 climbing out immediately with 50% gas to 20k the 100% fuel took 5:30, 50% gas 5:05.
pity the 14 is so pricey. when i fly her i have fun but am thinking . . . paid too much for this and all its going to get me is chased all over the place. :lol
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WOnder how the new and improved G10 and sp14 of AH2 stack up. They are made and ready to fly.
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Autoclimb is only good at low alts. As alt increases you need to lower climb speed (IAS). On autoclimb every single plane in AH climbs worse than really can if you know what climbspeed you need at spesific alts.
The climb table at fourthfightergroup states 5.1 minutes to 20k in a cleaned up and polished Spit14 with gunports and muzzles covered + streamlined blanks over the 20mm gun barrels.
Hap, to test climb you should take off and imediately engage autopilot-level wait until the speed reaches climbspeed (175mph) and then engage autoclimb and the timer.
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Standard procedure was to tape gun ports for operational use.
Anyway, autoclimb or not, would a 109G2 outclimb a Spit XIV??
At least it does in AH.
Now the particular plane climbing in 5 minutes to 20 K had a trop filter and an enlarged radiator. 15 minutes would suffice to 40K!, and max speed was 447mph at 25600 feet.
A flying testbed, Spitfire mk VIIIG (very similar to the XIV), exceeded 5000 fpm climb at sealevel, and maxed out at 445 mph at 25000 feet.
Boost on both of those was a "humble" 18.
I'll try to dig out what the boost-monster spitties did though (25 boost), - but many old spit jocks say it was the very best one.
We'll never see that in AH though I guess....it's just too good!:D
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The climb table at fourthfightergroup states 5.1 minutes
That's the prototype with lower critical alt in low gear. The production aircraft should be considerable better.
The production aircraft reached 9,000ft in 1 min 56.5 secs. 9k to 14k should take 1 min 13.2 secs, 14k to 20k should take 1 min 37.6 secs.
That's 4 mins 47 seconds to 20k.
with gunports and muzzles covered
Gunports are covered by red fabric, cannon muzzles by a rubber sleve (condom in some cases). This is the normal condition for every Spitfire.
streamlined blanks over the 20mm gun barrels.
No, the streamlined blanks are fitted over the empty cannon stubs, not over the guns.
It was also fitted with a rear view mirror above the canopy, which we don't have in AH.
Autoclimb is only good at low alts. As alt increases you need to lower climb speed (IAS). On autoclimb every single plane in AH climbs worse than really can if you know what climbspeed you need at spesific alts.
For the Spit XIV tests, A&AEE used a climb speed of 175 mph indicated on the ASI. So the IAS should be arround 175 mph from sea level up to around 22,000ft.
Angus, there're figures for the Spit VIII on 25lbs boost at http://www.fourthfightergroup.com/eagles/spit8.html
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Wow, 5500 feet climb from the deck, still doing above 5000 fpm at 11K!!! Looks like the ultimate Lala killer, hehehe.
Of course 400 mph plus in the close to 15K vicinity don't spoil it! And it's a good bit lighter than the Spit XIV!
Nice Nashwan,,,,NICE :D :D :D
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Originally posted by Angus
Wow, 5500 feet climb from the deck, still doing above 5000 fpm at 11K!!! Looks like the ultimate Lala killer, hehehe.
Of course 400 mph plus in the close to 15K vicinity don't spoil it! And it's a good bit lighter than the Spit XIV!
Nice Nashwan,,,,NICE :D :D :D
Expect that this "5500 feet climb rate" is a theoretical value, Angus. The dataset refers to a plane that had it`s radiators closed for the test. Nice trick Mike, not mentioning that, but anybody that reads the page for the JL 165`s trials at
http://www.fourthfightergroup.com/eagles/jl165.html
will find the reference to this "5500 fpm" Mk VIII test at +25 lbs boost by Vickers Armstrong, is doing 5580 fpm, but with radiator flaps closed.
Closing radiators was not possible on any serial Spits after the Mark V series : there was no provision to control the radiator flap position manually, they were automatic only (see any Mk IX, XIV etc. Flight Manual), banging out open very soon when running with so little airflow through them - as in a climb - for cooling. Result : decreasing the climb rate by apprx. 700 fpm at all altitudes (see JL165`s climb being 5740 with force-closed rads, and 5080 fpm with open ones). Now that`s one side of the coin - the other, the fact being that the Merlin 66`s supercharger was not designed to provide +25lbs boost on it`s own, and was unable to keep it up in MS gear for more than a mere 500ft up from SL... see boost tables again :
http://www.fourthfightergroup.com/eagles/jl165climb.gif
These Spit-myths are just so numerous ;)
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Closing radiators was not possible on any serial Spits after the Mark V series : there was no provision to control the radiator flap position manually, they were automatic only (see any Mk IX, XIV etc. Flight Manual), banging out open very soon when running with so little airflow through them - as in a climb - for cooling.
Well, the colling report shows that a 25 lbs boost climb could be maintained for 5 minutes without the coolant passing it's maximum temperature, when the rad flaps were shut, so for a considerable portion, at least, of a climb the rad flaps would be shut.
It should also be pointed out that the Spit VIII had a worse climb rate than the Spit IX (it was 370lbs heavier).
The report notes that climb rate is increased by the use of higher boost by approx 950 ft/min, and a normal Spit LF IX should have a climb rate of 4500 ft/min+ with 18lbs boost.
It should also be pointed out Rolls Royce got a figure of 5,740 ft/min with the same underperforming Spit IX the A&AEE used.
What condition was used for 109 climb tests? I believe you said shut, or partially shut, on Butch's board, didn't you?
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Of course ... Izzie will read that and gladly make a concession if not an outright reversal in judgement that may reflect positively on something not of German manufacture, Nashwan. :D
Luftdweeb: Luftwaffe is da chit!
RAFdweeb: No ... you is da lie ... RAF is da chit!
AAFdweeb: No you both lie ... USAAF is da chit!
NAVdweeb: Unless you count the US Navy it's da chit!
Everyone to everyone: No you all lie you is da suck!
Everyone to everyone: Oh yeah?! Prove it that I is da suck and you is da chit!
(And the chart/graph/interpretation version of WWII continues)
[/B]
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All german climb tests are flown with cooler settings at "climb flight settings"(steigflugstellung: half open at 220mm) up to the rated alt. Then changing from half open to "high speed setting"(schnellflugstellung: 65mm open) till 2500m to 3000m above the rated alt. From this point up to the service ceiling the radiator setting was fixed on high speed setting.
The power setting was at Steig&Kampfleistung.
...
The G-2 does 6000m(18k ft) at 5:45, and 7000m(21k ft) at 7:00 with 100% throttle and radiator flaps partially open. Maybe it's because AH planes don't overheat, don't have to worry about using emergency power at climbs, and the radiators are always considered closed, that the G-2 outclimbs Spit14 in AH.. who knows?
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Oh, btw, either the climb test wrong, or HTC is lying - but AH data shows the Spit14 outclimbs the G-2, WEP or no WEP. Only when the Spit14 is running on normal power and the G-2 on WEP, does the G-2 outclimb it.
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in offline test, g2 did not out climb spit 14
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Originally posted by Nashwan
That's the prototype with lower critical alt in low gear. The production aircraft should be considerable better.
BS. Why do you bring the same lie over and over again?
When the supercharger uses less revolutions, there remains more excess power on the prop shaft. The Spit14 in this test had a ~2000hp griffon up to 2k. See my picture to understand what would be a realistic climb rate with a reduction ratio that gives 9k critical alitutde. And this straight green line i drew is even optimistic, the realitic curve would run below it between 2k and 22k due to atmospheric conditions.
niklas
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Yeah! You is da biased. I is not da biased. My favorite plane is da chit! Yours is da suck![/b]
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arlo, you are teh suckest of teh sux.
not to mention biased against everything :D
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We all know the only real conclusion that can be reached from this debate--
Arlo is d@ REAL chit!!11!1!
:D
BTW niklas, although I do agree with the sentiment in your sig, I think it deserves a better wording: "The only good spitfire is a burning spitfire"
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QUOTE]Originally posted by Nashwan
That's the prototype with lower critical alt in low gear. The production aircraft should be considerable better.
BS. Why do you bring the same lie over and over again?
Niklas, before accusing me of lying and Bull****, perhaps you could read what I said, and more importantly THE POINT I WAS REPLYING TO.
GScholz said:
The climb table at fourthfightergroup states 5.1 minutes to 20k
To which I replied:
That's the prototype with lower critical alt in low gear. The production aircraft should be considerable better.
The prototype with a lower critical alt undoubtedly had a better climb rate below that critical alt, which was about 2,000ft iirc. However, it undoubtedly had worse climb above that critical alt, compared to the production model with increased supercharger gear speed.
The production aircraft could maintain 18lbs boost up to 9,000ft, the prototype, which had a better climb rate below 2,000ft, had dropped to 12.9 lbs by 8,000ft.
To compare the climb rates:
The production aircraft reached 9,000ft in 1 min 56.5 secs. 9k to 14k should take 1 min 13.2 secs, 14k to 20k should take 1 min 37.6 secs.
That's 4 mins 47 seconds to 20k.
The prototype reached 20,000ft in 5.1 mins, which either means 5 mins 6 secs, or 5 mins 10 secs. Either way, it takes longer to get to 20,000ft than the production machine.
So when I replied to
The climb table at fourthfightergroup states 5.1 minutes to 20k
with
That's the prototype with lower critical alt in low gear. The production aircraft should be considerable better.
I was 100% correct. You seem to have assumed I was speaking about the climb rate below 2,000ft, when I was talking about the overall climb rate up to 20,000ft, as was the quote I was replying to.
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...and is that a Spit XIV with 150 octane fuel or not?
Those figures for the Spit XIV are with normal 100 octane fuel, at 18 lbs boost (or very close to it)
Edit: What happened to Squire's post?
Niklas:
When the supercharger uses less revolutions, there remains more excess power on the prop shaft.
I don't know anyone who'd argue with that. As to how much difference, I believe we argued that one already, and I don't have the energy to go over it again.
See my picture to understand what would be a realistic climb rate with a reduction ratio that gives 9k critical alitutde.
I'm not 100% sure what your point is here. Are you saying we should use your calculations instead of the climb chart we have for the production Spit XIV? I'd rather believe the actual tests, thanks.
However, there isn't that much difference between your calculations and the real test results. You seem to be showing about 4,550 ft/min up to 9k, the test results show an average of 4650 ft/min. Note, however, that the Spit on this test seems to be climbing a bit better than the prototype, in general. Where the prototype had a climb rate of 3,600 ft min, the production plane has 3,700 ft/min. Add the same 100 ft/min to the calculations you've done, and you arrive at the same figures the A&AEE did when they did the tests.
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OOO-HOOOO warming up are we?
Hap:
"Oh, btw, either the climb test wrong, or HTC is lying - but AH data shows the Spit14 outclimbs the G-2, WEP or no WEP. Only when the Spit14 is running on normal power and the G-2 on WEP, does the G-2 outclimb it."
Don't know where to see that result, but a stopwatch brought me those results (error may be 3 secs or so, tops ):
Spit XIV, no wep, full load, with takeoff roll, 20K 6:46 Spit XIV, w. WEP, full load. with takeoff roll, 20K 5:50
in Real life this should be about 5 minutes, no WEP mentioned.
So the Spit XIV is definately porked. It actually gets outclimbed by the AH 109G2!
109G2 no WEP, full load,no gonds, with takeoff roll. 20K 6:34 109G2 w. WEP, full load,no gonds, with takeoff roll, 20K 5:48
Niklas:
I don't give doodly-squat about your quite advanced logistics about the gears and alt-bands, atmospheric pressure and so on. The fact remains. An EARLY production line Spitfire XIV of 8400 lbs climbed to 20K in 5 minutes/5 minutes 6 seconds in the test pilots first flight BTW... with NO engine overheating, using the boost of 18. Calculate as you want, this is a clocked test, (and probably a careful one regarding the engine). Wanna go to Newtons? Will make a quick calculation, but would LOVE to have a comparitive number from a different plane to 20K, hehe.
And Isengrim....a cookie for ya
:D
"Expect that this "5500 feet climb rate" is a theoretical value, Angus. The dataset refers to a plane that had it`s radiators closed for the test. Nice trick Mike, not mentioning that, but anybody that reads the page for the JL 165`s trials at
http://www.fourthfightergroup.com/eagles/jl165.html
will find the reference to this "5500 fpm" Mk VIII test at +25 lbs boost by Vickers Armstrong, is doing 5580 fpm, but with radiator flaps closed. "
Well, will have to dig deeper to verify your statement about no other planes of this versions being able to close the radiator flaps
However, what an amazing test, climbing like that with the flap closed without harming the engine?!?!?!?!?......after all, that's what the plane did! And it kept on to what,,,,,20K+????
I'll look into it :D :D :D :D
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Oops musta hit the wrong key.
Do we know what version the HTC XIV is supposed to have for fuel?
As to its turn rate compared to the IX I would expect it to be somewhat less at lower speeds due to the added weight, the test says same turning circle, but not at what speed and alt?
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The test indicates a max turn "chase"
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Originally posted by GScholz
Hap, to test climb you should take off and imediately engage autopilot-level wait until the speed reaches climbspeed (175mph) and then engage autoclimb and the timer.
If you look at the A&AEE test of the Spit XIV, it's clear they either began the test staionary, or at wheels up, not at climb speed.
The table gives the time taken to reach 1,700 ft as 35 seconds, which equals a climb rate of just under 3,000ft/min. The plane was actually capable of over 5,100 ft/min.
If you assume a climb rate of 5,100 ft/min, 1,700 ft should take 20 seconds, which means 15 seconds wasted taking off/getting up to climb speed after takeoff.
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Well they have different corner velocities, and they also bleed energy at different rates, so Im not sure what to make of that either. I have no doubt the XIV could turn a hard corner, it should.
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Nashwan: you're spot on there.
I recall reading about the tests being made from a heated and running engin. Clock starts at opening up.
The Spit is nice there. Never saw a warbird taking off as easily as a Spit. If you count out biplanes, and,, ,, ehhh, Hurricanes actually.
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Spit XIV, no wep, full load, with takeoff roll, 20K 6:46 Spit XIV, w. WEP, full load. with takeoff roll, 20K 5:50
in Real life this should be about 5 minutes, no WEP mentioned.
So the Spit XIV is definately porked. It actually gets outclimbed by the AH 109G2!
109G2 no WEP, full load,no gonds, with takeoff roll. 20K 6:34 109G2 w. WEP, full load,no gonds, with takeoff roll, 20K 5:48
So you're saying the guys who made this sim, lied when they posted the charts for their game, and your testings are absolutely right?
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Originally posted by Angus
Tested some climbers offline, just for fun....
Spit XIV, no wep, full load, with takeoff roll, 20K 6:46 Spit XIV, w. WEP, full load. with takeoff roll, 20K 5:50
in Real life this should be about 5 minutes, no WEP mentioned.
So the Spit XIV is definately porked. It actually gets outclimbed by the AH 109G2!
109G2 no WEP, full load,no gonds, with takeoff roll. 20K 6:34 109G2 w. WEP, full load,no gonds, with takeoff roll, 20K 5:48
Angus, Angus, Angus *shakes head* AH Spit14 on WEP is running 18lbs boost, 16lbs no WEP. The climb table at fourthfightergroup clearly stated 18.3lbs boost at SL and 18.3lbs boost where the SC could handle it. The test was done WITH "WEP".
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Fun being on this side of the argument for a change! ;)
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dunno what all the #'s are about; loadup a 14 with 303's and no bombs; take off, hit wep, level to end of run way hit alt-6, 4:53 later give or take a sec, you'll be at 20k. wep dies about 19k.
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Kweassa: AH speed chart does not mention time to altitude, nor do HTC's webcharts give an absolute time to alt. The only things you can read out of the charts is climb rate at alt bands. So I checked it with a stopwatch. Guess what inspired me? Well, I had been flying the G-2 and found the climb rate quite impressive.:D
Oh, and Gscholz: the test I refer to is probably not the same as the one from fourthfightergroup. The only thing I can dig out about the engine is that it's an 18 boost engine, but whether it was applied in the test is not mentioned, however would be likely from the numbers.
None the less, sitting on the runway to 20K it is still almost a minute too slow, and slower than the G-2 (which may however be the case, would love to have recorded figures for the G-2)
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You're still wrong Angus. According to the climb table the Spit14 in the test reached 1700 feet in 0.35 minutes and 4000 feet in 0.8 minutes. The test was clearly not from "sitting on the runway", but rater already airborn, or at climbspeed rolling down the runway and timed from wheels-up.
http://www.fourthfightergroup.com/eagles/jf319.html
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What Nashwan said:
"If you look at the A&AEE test of the Spit XIV, it's clear they either began the test staionary, or at wheels up, not at climb speed.
The table gives the time taken to reach 1,700 ft as 35 seconds, which equals a climb rate of just under 3,000ft/min. The plane was actually capable of over 5,100 ft/min.
If you assume a climb rate of 5,100 ft/min, 1,700 ft should take 20 seconds, which means 15 seconds wasted taking off/getting up to climb speed after takeoff."
Aha, see he has it wrong! 0,35 minutes is only 21 sec,has to be from liftoff. However, our AH spit only climbs to 1200 feet in that time. Awwww, this is getting frustrating
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I get a little over 1600 feet in 20 seconds when TO at climbspeed.
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I started clocking at "gear up", still a few secs away from 170 mph
pewwie, gotta clock everything again.
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Ok so the bottom line is that you don't have any documentation to support your claims that the AH Spit14 is under modelled. You don't even have documentation that can justify the AH Spit14's current performance.
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My mistake, it is .35 minutes instead of 35 seconds. In my defence, it was late, and I was tired :(
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Well, GScholzie, got a present for you ;)
Levelling after gear raise at roughly 175 mph, climb at 170 mph, I get to 1700 feet in 21 secs!!!
I roughly stay on the "line" of the fourthfightergroups figure all the way up to 20K. I am actually a couple of seconds faster than their figure, - but, alas, I did not set my fuel burn to the right figure, so I guess AH is totally spot on there.
It goes very much wrong after 20K though, the AH spit being lighter, but none the less a lot slower in the climb. It is a minute slower to 30K, and a whole 7 minutes slower to 40K
That would indicate that our XIV is porked actually ;)
Well, it has the low alt performance of a high alt Spit XIV, and a high alt performance of a low alt Spit XIV. It gets outclimbed by a humble 109G2, and costs you perkies!!!!yeachhh
Anyway, honestly, nice to have help to get the test method right. Looking at it, the pilot would have to have done it this way, - he needs his arms for controls, he needs to write things down on his kneepad, a logical moment to start is by retracting UC, levelling to gain speed, start the stopwatch, and pull the stick!
Of course it would have been logical to start the stopwatch as one opened the throttle, but that's that.
So, my documentation DOES support the undermodelling of the Spit XIV, presumably at high alt, and to the best knowledge it is by far not performing properly in the turn. I hope that test pilot reports are good enough for that
:p
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Oh, BTW, how do you set fuel burn to Real Life value in the offline mode? And where can I get a good stopwatch for my desktop??
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Angus, did you reduce climb speed after 20K or did you just ride the autoclimb?
If you see the climb table at fourthfightergroup you will notice that as alt increases beyond 20K you need to reduce airspeed to get the best climb. Up to 20K you should have an IAS of 175mph, but at 30k it should be 151mph and at 40k 121mph, but there are many increments in between those alts. Also note that the test AC used 18.3lbs boost for longer than the 5-minute operational limit which is forced in AH.
I love being on this side of the argument for a change. I can see how much fun you guys must have had in the LW threads! :D
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I rode the autoclimb on 170, and tortured the WEP every minute or so.
Actually, the plane manages a bit above 40K,however at that alt it's practically riding on the prop, and I presume the total ceiling is close to 41K instead of 44
I did not lower the speed as to those you mentioned, but will try at opportunity. BEI GELEGENHEIT! I doubt it will make up whole 7 minutes though. WeŽll see.
Oh, and I do enjoy the LW threads very much indeed, hehe.
Will post later with speed comparisons etc, gotta go feed my cows:)
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So you're saying a certain plane that boasts a higher rate of climb compared to another certain plane, at all altitude bands, actually climbs slower?
What's the G-2 you tested equipped with, a hyperdrive? :D
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"Teh Schpittfire was teh sukiest suk suk fitar in teh hole worl! It is teh way uber-modeled plane! Teh 109 was way muchest bettar and is teh CHIT!"
"No ... teh Spitfare is the bestest best and is porked way bad worser den it shood be. It is teh watermelon and kood kik yer gran-dad's butt!"
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Originally posted by Kweassa
So you're saying a certain plane that boasts a higher rate of climb compared to another certain plane, at all altitude bands, actually climbs slower?
What's the G-2 you tested equipped with, a hyperdrive? :D
One thing you must consider is that the 109G2 has twice the WEP time of the Spit14. Without WEP the Spi14 is a very average climber at about 3500 fpm, while the 109G2 still on WEP climbs 4500 fpm at 5k falling to 3500 fpm at 20K.
The 109G2 should out climb the Spit14 to 20K, but over 20K the Spit gains the advantage.
The Spit will out climb the 109 at first but when it reaches 8-9K the Spit looses power due to the two-stage SC and the 109 will gain superiority in climb for the next 10K. They should be pretty close to 20K.
The Spit14 is a 5-minute monster plane that becomes very average after, much like the 109G10 ... except it's a 10-minute monster that is a bit faster on the deck, which is more useful for escaping.
I wouldn't say the Spit14 is undermodelled, but it is definitively overperked.
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i dunno understand. you take a g2, me spit14 lets climb. nefsed.
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Sure, I'll take the 109G2.
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Originally posted by GScholz
One thing you must consider is that the 109G2 has twice the WEP time of the Spit14. Without WEP the Spi14 is a very average climber at about 3500 fpm, while the 109G2 still on WEP climbs 4500 fpm at 5k falling to 3500 fpm at 20K.
The 109G2 should out climb the Spit14 to 20K, but over 20K the Spit gains the advantage.
The Spit will out climb the 109 at first but when it reaches 8-9K the Spit looses power due to the two-stage SC and the 109 will gain superiority in climb for the next 10K. They should be pretty close to 20K.
The Spit14 is a 5-minute monster plane that becomes very average after, much like the 109G10 ... except it's a 10-minute monster that is a bit faster on the deck, which is more useful for escaping.
I wouldn't say the Spit14 is undermodelled, but it is definitively overperked.
I killed a Spit14 earlier this tour with a G-2. He tried to escape in a steep climb... Whoops, he'll think twice about that next time. I then went after his useless Spit9 wingman. A few minutes later, I chased down a 262 and shot off one of his elevators. He then augered, unable to pull out of his dive... Poor lil' lambchop. You have to love the under-used G-2.
My regards,
Widewing
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To justfy its perk price and perk tag while still offering survivability the Spitfire Mk XIV should have been modeled with 150 octane fuel. At that point it would have had the speed to escape (390mph on the deck) the gang bang its perk tag brings on it.
As it is it isn't fast enough to run and can only climb away in favorable situations (i.e., nobody above you) and can never climb away from some aircraft. As it is the Spitfire Mk XIV should either not be perked or not have a SPIT14 icon.
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The Spit14 needs to be perked, but not so much.
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Why does it need to be perked? It sucks :D
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Should be around 4~8 perks.
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I doesn't suck bad enough! :D
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Originally posted by Kweassa
Should be around 4~8 perks.
Your own "Perk Agenda" says 20! :D
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I changed my mind after that. ;) The NPA has been discussed a loooong time ago!
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Spit XIV, no wep, full load, with takeoff roll, 20K 6:46 Spit XIV, w. WEP, full load. with takeoff roll, 20K 5:50
A fully loaded Spit XIV of production line will climb to 20K in 5 minutes smooth. In AH it takes close to 6 minutes, so the XIV is porked in that way.
Does FS and MS stand for Full stage supercharger and medium stage supercharger?
F Mk XIV, XIVE, FR Mk XIV, FR Mk XIVE.
Engines: Griffon 65, two speed, two stage super; 2,035hp at 7000ft, 1540 at take of (MS), 1,820 at 21,000ft (FS).
Griffon 85 (used for the spit 14 with counter rotating props I believe, need to read up more on it). 2,055hp at 2,750rpm 8,250ft.
Griffon 61 1,785hp at take off with 2,750rpm.
Fuel: 100 octane 18 boost (should be what we have in AH as we too have 18 boost WEP). 150 octane gives 21 boost.
Performance
Max Speed: 439 at 24,500ft (FS), 404 at 11,000 (MS), 274 at 30,000ft (FS), 220 at 35,000ft (FS). 357 at Sea Level (MS). Normal Cruise 362 at 20,000. Max dive 470.
Rate of climb 4,580ft/min at sea level (MS), 3,700 at 22,500ft (FS), 4,700 at 8000ft (MS).
Time to 20,000 7 min. Service cealing 43,000. Stall: Flaps up 87mph, down, 75. Landing 75.
Source: Spitfire The History by Eric B. Morgan and Edward Shecklady.
ISBN: 0-946219-48-6
I highly recomend it although I haven't taken the time to read a whole lot in it yet, very interesting but also very long, over 600 pages of pure facts.
Karnak, maybe you can help, which spit 14 do we have? F or Fr or non of those two? The "E" had clipped wings, right?
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To justfy its perk price and perk tag while still offering survivability the Spitfire Mk XIV should have been modeled with 150 octane fuel. At that point it would have had the speed to escape (390mph on the deck) the gang bang its perk tag brings on it.
I completely agree with you Karnak, but this should go for the Ta152 and the F4u4 aswell although the F4u4 is the one of the three with highest survivabilty thanks to it fast deck speed which is about the same of the LA7.
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Does FS and MS stand for Full stage supercharger and medium stage supercharger?
Full speed and medium speed, I think.
Certainly on the Merlin, both stages run all the time, but there are two different speeds. It's the speeds that change, not the stages. I haven't checked, but I'm pretty sure it would be the same for the Griffon.
Karnak, maybe you can help, which spit 14 do we have? F or Fr or non of those two?
AH has the F XIV. The FR stands for fighter-recconisance, and had a camera mounted in the rear fuselage (in addition to the guns).
The Griffon 65 was limited to 18 lbs boost on 100/130 fuel (100 octane), and at least 21 lbs on 100/150. Neil Sterling has posted documents from mid summer 44 (iirc) that say the Griffon 65 is limited to 21lbs boost because of main bearing problems, but will be capable of 25 lbs later on.
I have seen one pilot's account saying they were anxiously awaiting their Fr XIVs because it's engine allowed higher boost than the F XIV, but I suspect that's just because they were newer machines, and probably incorporated modifications. (Can't remember the source now, so I can't check the details)
At the same boost levels, the Fr XIV should have a slightly worse climb than the F XIV, due to the extra weight.
The Griffon 65 gained about 200 hp going from 18 lbs boost to 21 lbs, and gained about 500 hp going from 18lbs to 25 lbs. The AH Spit XIV has 18 lbs.
The "E" had clipped wings, right?
Wing tips are independent of wing type. You could have C or E wings on the XIV, and either normal or clipped wings (never seen a XIV with extended tips, but I should think they were possible as well). Wether the Es were all made with clipped wings or not I don't know, but wingtips could be changed easily in the field, so there was probably a combination of types in service.
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Originally posted by Angus
None the less, sitting on the runway to 20K it is still almost a minute too slow, and slower than the G-2 (which may however be the case, would love to have recorded figures for the G-2)
In the test flights conducted by Finnish Air Force G-2 climbed from approx. climb speed at sea level to 6000m in 5min 5s.
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Thanks Nashwan :)
I fail to see a problem with our spit 14 as it's modelled with 100 octance fuel. Only thing would be too good climb rate bellow 8k or so.
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Originally posted by Wilbus
Karnak, maybe you can help, which spit 14 do we have? F or Fr or non of those two? The "E" had clipped wings, right?
We have a Spitfire F.Mk XIV.
It has the option for the .303s and it lacks the fuel tank behind the pilot.
The fuel tank is the most significant as it it reduces both range and weight. Reduced weight of course should also mean a bit higher performance.
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Originally posted by Nashwan
The production aircraft reached 9,000ft in 1 min 56.5 secs. 9k to 14k should take 1 min 13.2 secs, 14k to 20k should take 1 min 37.6 secs.
That's 4 mins 47 seconds to 20k.
The prototype reached 20,000ft in 5.1 mins, which either means 5 mins 6 secs, or 5 mins 10 secs. Either way, it takes longer to get to 20,000ft than the production machine.
I was 100% correct [/B]
Well, youŽre right at the first look the production aircraft would climb faster to 20k ( i misunderstood you, sorry) , but i wouldnŽt call it considerable better. Furthermore i get 4.86min to 20k (4min 52sec) and i already said that the 4550ft/min is rather optimistic. Atmosphereic pressure drops quicker at low altitudes, so 4300f-4400ft/min would be more realitic in 1st gear than 4550.
My calculations say the AH spitfire, according to the charts, will need only 4.55min or roughly 4min 30sec. to 20k
niklas
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The second production run that was done during the summer when the factory tools were slightly larger and more maleable gave a critical differential of .00127983492 in the size of the rivets used to secure the dynamic gimbling to the camphorgesic widget thereby causing a loss of .0020457834 negative psi to the airflow coefficient.
But you're completely ignoring the fact that during that run they procured rivets that were made of type 97 aluminum to offset the differential thereby actually increasing the reduction of the critical negative psi which made the plane climb faster and mo better than you seem to think it don't.
No, it shows right here in this here chart that the flabbergastrum tendency of the hemophicoptic latitudinal plate overlaps the gradient lasitometer reading by over .003979539 thereby backing up my claim and disproving yours!
On the contrary. The chart, when compared to THIS chart (from an even more reliable source than yours, might I add) shows that the bernealian factor was left out and didn't figure in the klappimatic effect.
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Oh yeah Arlo my planes better then yours . Because, yo mommas a poopyhead too.
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The fuel tank is the most significant as it it reduces both range and weight. Reduced weight of course should also mean a bit higher performance.
For good and for bad than, shorter range but a bit better performance. Acording to what I posted before our XIV looks to be climbing about 500 feet/min too fast at the deck, do you have any charts Karnak? I can't find any.
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Originally posted by Wilbus
For good and for bad than, shorter range but a bit better performance. Acording to what I posted before our XIV looks to be climbing about 500 feet/min too fast at the deck, do you have any charts Karnak? I can't find any.
Not that I can think of off hand.
I was surprised by the initial climbrate of HTC's model of the Spitfire XIV as well. I was expecting the 4,580ft/min figure.
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Originally posted by Nashwan
[B.
Wing tips are independent of wing type. You could have C or E wings on the XIV, and either normal or clipped wings (never seen a XIV with extended tips, but I should think they were possible as well). Wether the Es were all made with clipped wings or not I don't know, but wingtips could be changed easily in the field, so there was probably a combination of types in service. [/B]
Most of the XIVs that flew in Europe had full span wings. Lots of photos of E Wing Spit XIVs on the continent with full span wings until the end of the war. XIVs in the Pac also had full span wings. I think the clipped XIVs were more of a postwar deal.
I have a photo in my collection of Ginger Lacy's 17 Squadron Spit XIV postwar with clipped wings while stationed in Japan. When he was flying it before the end of the war it had full span wings.
Certainly it was something that could be done as needed and you'd find both clipped and full span winged Spits in the same squadrons.
The clipped Wing Spits were mainly the Vbs early on to increase the roll rate and when they were optimized for low alt work and then the 2TAF IXs and XVIs as they were doing the ground support work.
Dan/Slack
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Originally posted by Nashwan
Well, the colling report shows that a 25 lbs boost climb could be maintained for 5 minutes without the coolant passing it's maximum temperature, when the rad flaps were shut, so for a considerable portion, at least, of a climb the rad flaps would be shut.
Not quite, you are misqouting the report. The report deals with the same JL 165 MkIX, which had a additional device installed to keep the rad flaps in shut position. In the report they state the "suitability" of the radiator is just enough for "temperate" conditions, but unsatisfactory for "tropical" conditions. Given that most of the report is calculations based on some flight tests with pre-determined numbers for "satisfactory results", it`s hard to say how much really it means it won`t overheat. In any case, the radiator flaps would soon open just as the temperature passes the "normal" level (about 90 deg IIRC), decreasing climb rate as mentioned. And there`s no override to that.
It should also be pointed out that the Spit VIII had a worse climb rate than the Spit IX (it was 370lbs heavier).
Yep, it`s about 200 fpm worser than the Mk. IX, which cuts in very nicely with the decrease in climb rate with clipped models, suffering from the same wingload increase.
The report notes that climb rate is increased by the use of higher boost by approx 950 ft/min, and a normal Spit LF IX should have a climb rate of 4500 ft/min+ with 18lbs boost.
It should also be pointed out Rolls Royce got a figure of 5,740 ft/min with the same underperforming Spit IX the A&AEE used.
Uhm, if a "normal" Spit could do ~4500 fpm, and increasing the boost would raise that by about 950 fpm (4500+950= 5450 fpm), than how could RR`s Spit be "underperforming at 5740 fpm?
At Rollce-Royce`s test the "same underperforming Spit IX" was very close to it`s official specs at 399 mph max speed. With the same plane A&AEE mesured 389 mph as max speed, so clearly, for some reason, in the RR tests the plane was perfectly representative of an avarage spitfire.
What condition was used for 109 climb tests? I believe you said shut, or partially shut, on Butch's board, didn't you?
I said they were about halfways open up the the FTH, and from then onwards, about 1/4-1/3 open. This is to what most German tests refer to, ie.radiators being "Automatik". Of course since the 109 pilot could override automatic control of his radiators, he could shut them more, reducing drag and increasing his climb rate at the expense of overheating - but as we know, late 109s had double the WEP time than Spits.
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Originally posted by Angus
Don't know where to see that result, but a stopwatch brought me those results (error may be 3 secs or so, tops ):
Spit XIV, no wep, full load, with takeoff roll, 20K 6:46 Spit XIV, w. WEP, full load. with takeoff roll, 20K 5:50
in Real life this should be about 5 minutes, no WEP mentioned.
So the Spit XIV is definately porked. It actually gets outclimbed by the AH 109G2!
109G2 no WEP, full load,no gonds, with takeoff roll. 20K 6:34 109G2 w. WEP, full load,no gonds, with takeoff roll, 20K 5:48
Well if that`s the case, then both planes are porked. The XIV`s figures seem to be low, didn`t check it, but I checked the G-2s climb times.
ie. real-life figures :
Finnish tests:
109G2 no WEP, full load,no gonds, 20K = 5:03 min
German tests at rechlin
109G1 no WEP, full load,no gonds, with takeoff roll. 20K 5 : 14
vs. your 6 : 34 min.
These figures were done at 30-min rating at 1.3ata, the maximum WEP would be 1.42ata for about 10% more power at all altitudes, with an appx. same level increase in climb rate. Dunno how much would that be in climb time, guess somewhere between 4.5 and 5 mins to 20k.
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Originally posted by Wilbus
F Mk XIV, XIVE, FR Mk XIV, FR Mk XIVE.
Performance
Max Speed: 439 at 24,500ft (FS), 404 at 11,000 (MS), 274 at 30,000ft (FS), 220 at 35,000ft (FS). 357 at Sea Level (MS).
Normal Cruise 362 at 20,000.
Max dive 470.
Do I understanding it right and "Normal Cruise" refers to the highest obtaiable speed (362mph/583kph) that could be kept up w/o the engine overheating ? What engine setting ?
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Yes, normal cruise would be the "cruising" speed of the plane, not flying on emergency power or military power.
However I believe it could cruise faster without the engine overheating. I can't find the engine settings for cruise.
Maybe Nashwan or Karnak know it?
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None the less, sitting on the runway to 20K it is still almost a minute too slow
Please Angus, from where do you get your numbers? A source please, as it is now the only "porked" thing about it is the climb rate, this could very likely be because of the lack of a fuel tank but it does not (atleast not from the numbers I and others have posted) climb too slow. It actually climbs 500ft/min too fast at the deck.
Source?
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Given that most of the report is calculations based on some flight tests with pre-determined numbers for "satisfactory results",
The "pre determined numbers" are the permitted coolant temperatures."Satisfactory results" are temperatures lower than the permitted coolant temperatures.
Yep, it`s about 200 fpm worser than the Mk. IX, which cuts in very nicely with the decrease in climb rate with clipped models, suffering from the same wingload increase.
If you clip the wings of the Spit IX, you may get a wingloading increase to the same as a Spit VIII (I haven't checked), but of course you still have a higher power to weight ratio, which has far more effect on climb rate than wingloading, so you would still outclimb the Spit VIII.
Uhm, if a "normal" Spit could do ~4500 fpm, and increasing the boost would raise that by about 950 fpm (4500+950= 5450 fpm), than how could RR`s Spit be "underperforming at 5740 fpm?
Because the 4500+ figure is with rad flaps open. RRs test of JL165 was with rad flaps shut.
At Rollce-Royce`s test the "same underperforming Spit IX" was very close to it`s official specs at 399 mph max speed.
It was 397 mph, and that is lower than similar Spits. MA548, with an SU fuel pump instead of carb, did 411 mph. (The SU pump increased the speed of the Spit V by 5 mph). BS543 did 407mph, BS310 did 404mph.
With the same plane A&AEE mesured 389 mph as max speed, so clearly, for some reason, in the RR tests the plane was perfectly representative of an avarage spitfire.
Apart from being 5 - 10 mph slower than any other Spit IX, and having a climb rate 200 - 300 ft/min worse. (In the RR tests. By the time A&AEE tested it, it was 15 - 20 mph slower than other Spit IXs, and had a climb rate 500 ft/min worse.)
but as we know, late 109s had double the WEP time than Spits.
Do you have a cooling report on the 109? Because WEP time has no bearing on engine overheating. The Spit cooling report shows that after 5 mins at 25 lbs boost in level flight, the coolant was still way below permitted temperatures, even with the rad flaps shut. Got the figures for the 109? How long it could run at 1.98 ata with rad flaps shut, half open, etc?
German tests at rechlin
109G1 no WEP, full load,no gonds, with takeoff roll. 20K 5 : 14
No takeoff roll. The Rechlin figures for the G1 show 47 seconds to 1000m, 1 min 35 secs to 2000m. That works out at an average of 21 m/s for both the 0-1 km stretch, and the 1 - 2km stretch.
Also, the G1 reached 6000m in 5:14, 20,000ft would be 5:20.
These figures were done at 30-min rating at 1.3ata, the maximum WEP would be 1.42ata for about 10% more power at all altitudes,
1.42 ata was forbidden on the DB605 from June 1942 until June 1943, by which time production of the 109G2 had stopped.
vs. your 6 : 34 min.
I get 4:55 vs the actual 5:20.
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However I believe it could cruise faster without the engine overheating. I can't find the engine settings for cruise.
Maybe Nashwan or Karnak know it?
I don't know. The manual lists maximum continuous as 2400 rpm, 7lbs boost. It also lists a max 1 hr climbing limit of 2600 rpm, 9lbs boost.
Cruising implies a continuous rating to me, but wether it's the same as the max continuous figure above, I have no idea.
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Nashwan, I believe the coolant did not overheat when running on WEP (Spit and 109), but the piston heads and/or valves overheated. They would not be cooled at all except for the oil and excess fuel usage. The piston heads were designed to operate at high temps, but on WEP they would eventually overheat and could seize up the engine. The increase in coolant temp would be minimal, in fact what I have read is that the MW-50 and C3 injection used by the Germans actually reduced heat build-up since they had a heat dissipating/vaporizing effect. The 5 and 10 minute operational limit on the Spit and 109 is not dependent on coolant temp, but on the additional heat and stress on certain components of the engine.
EDIT: In AH this is simplified for all AC. All AC can run at MIL setting and max revs without running hot or damaging the engine, but in RL this was not so and different engines had different operational limits. AH does not model this AFAIK.
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Hey Wilbus
My mistake. The test clock was apparently started after takeoff, as soon as the plane entered climbing speed. So, out Spit XIV is actually spot on with the plane registered at the fourthfightergroup website. If it is too fast climbing in some zones up to 20K, it must thereby also be too slow in others.
However, performance above 20K seems to fall short, but I will have to look at it better.
Hey Isengrim: where do you find that data? I sorely need more tables of all 109 variants, (also the 190 actually), so if you have a nice thread, please post.
oh, - " but as we know, late 109s had double the WEP time than Spits."
What WEP time did Spits have? I know of Spits being run on "panic boost" for up to 30 minutes without engine damage.
Well, wish we had a better engine modelling in AH anyway :)
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i own a spit14, and fly it regular. Best plane my money can buy.
mines slightly modified, has 26" wings.
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Got any pics of that?
Must be kinda small though :D