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AaronGT
02-22-2004, 02:13 PM
I was reading the P51 performance
thread a did some testing and
confirmed that it underperforms.
However I also tried the 109K4 at
6000m and noticed that this also
underperforms.

I'd like to start a thread without
flames, ideally, where we can
share in game performance figures
in the 6000 to 8000m range so
we can compare them to real life
figures to see if there is any
consistent behaviour.

AaronGT
02-22-2004, 02:13 PM
I was reading the P51 performance
thread a did some testing and
confirmed that it underperforms.
However I also tried the 109K4 at
6000m and noticed that this also
underperforms.

I'd like to start a thread without
flames, ideally, where we can
share in game performance figures
in the 6000 to 8000m range so
we can compare them to real life
figures to see if there is any
consistent behaviour.

VW-IceFire
02-22-2004, 08:52 PM
I don't have any figures but are you thinking there may be something across the board where alot of aircraft don't perform as they should in this height range? Interesting...should be an interesting topic if people stick to the facts.

http://home.cogeco.ca/~cczerneda/sigs/temp_sig1.jpg
RCAF 412 Falcon Squadron - "Swift to Avenge"

Aaron_GT
02-23-2004, 03:20 AM
Well so far I've only tested the P51D5 and I
picked a competitor 109, the K4, and this was
also below official performance specs at around
this altitude. Now this could be that the K4 is
modelled to Russian test data rather than
official specs, and you can't necessarily
conclude anything from two planes. So if we
all pitch in and post the official specs, and
an FB test at around these altitudes (at an
altitude that matches available figures) then
we can quickly generate a matrix of results.

We can at least see if US aircraft are
undermodelled at these altitudes compared to
factory specs. Since German aircraft are
modelled according to Russian test data, that
will be a little harder to compare, but
we can at least compare to official factory
data there as well.

It might be helpful to Oleg as his team, what
with getting the expansion out, might not have
time to test all these aircraft. However given
that the Aces Expansion might change the FMs
a bit, it might be worth repeating the
exercise after that has been released.

If we can stick to the facts, behave in a
responsible manner, and avoid whining then
it might actually be a service to the community.

By the way - I think testing probably needs
to be done at

99% throttle and full throttle (without Forszah/
MW50/etc).

With the planes trimmed as far as possible
for level flight, on the Smolensk map in clear
weather,

Aaron_GT
02-23-2004, 03:21 AM
To start it off:-

P51D5 - 7600m - 99%: 650, 110%: 685, expected: 703

Willey
02-23-2004, 06:11 AM
I could keep 703 at 7600m... But it takes ages to accelerate from 690 to 700+ in level flight. That's what the British got out of that plane. The engine was totally overheated as they tried to reach 700 in level flight. When sinking slightly, and then leveling out, you can hold that speed. This makes sense as the P-51D, "empty" weight (no fuel, oil, ammo, pilot, therefore "") has a worse power/weight ratio than a TO weight 109K-4 or 190D-9.

02-23-2004, 07:36 AM
What histotical data I have found in Report no. NA-46-130, dated 2-6-1946 for P-51D airplane at 10 000 lbs, but w/o external load shows 705 km/h at 25k ft, or 7600m. However this is w/o external rack, which are AFAIK present on our D-5.. these would slow it down by 12mh/19kph at altitude, so in fact the 685 km/h is very close match.

I dont know what spec you reached with the K-4 at 6000m - historically the plane would reach 715 km/h. However when I tried a good while ago, it was very hard to reach it, I was some 50 km/h short, as the ball needs to be centered perfectly - hard to do by twisting the joystick, AND keeping level at the same time, correcting for torque as well.. I guess I have to buy/make a rudder pedal for myself. Centering the ball, and speeding up the process with a shallow dive got me about 700-710 - good enough. The K-4 seem the be close to its historical specs regarding speed, save that its too slow at SL - about 585 km/h vs. 607 km/h. But I dont whine about that, it still has the insane climb, and huge power reserve for even turning combat. You cant turn as well as the Yak, but you can wear him down with 2000 HP against his puny 1250 or so. http://ubbxforums.ubi.com/images/smiley/16x16_smiley-tongue.gif And the MK 108 is just a plane-vaporizer. Nothing really to complain about. Oh well, I miss the ability to shut off damaged radiators to conserve the coolant.

Aaron_GT
02-23-2004, 08:35 AM
Willey - you should post in Maple Tiger's thread too as he seems to be under the impression that
the P51D5 is currently criminally undermodelled.
I certainly couldn't get it past 685 after
about 5 minutes of level flight. Did you get
703 with ammunition on board?

Aaron_GT
02-23-2004, 08:36 AM
Kurtzfurst - I'll dig out what I got for
the 109K4. From memory it was about 60 km/h
less than 715.