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XyZspineZyX
08-17-2003, 03:16 PM
This is based on looking at the NACA report 868 charts
(page 166 of that report) for roll velocities with 50lb
stick force. Admittedly the plane we have modelled is
the P39N, and the P39D is the one in the report, but
the results look like this in FB:

speed km/h, (mph): roll rate in FB, (roll rate from NACA)
and finally the equivalent P63 roll rate for comparasion.

300 (180): 144 (65) (P63: 88)
400 (250): 96 (75) (P63: 108)
500 (310): 72 (62) (P63: 90 est)

Did the P39N in reality roll much better than the D version? In FB is it more than double the roll rate
seen in the NACA report at 300km/h. The P63 has a much
better roll rate, though, so does the P39N have some
of the improvements that found their way onto the P63 included?



Message Edited on 08/17/0302:28PM by AaronGT

XyZspineZyX
08-17-2003, 03:16 PM
This is based on looking at the NACA report 868 charts
(page 166 of that report) for roll velocities with 50lb
stick force. Admittedly the plane we have modelled is
the P39N, and the P39D is the one in the report, but
the results look like this in FB:

speed km/h, (mph): roll rate in FB, (roll rate from NACA)
and finally the equivalent P63 roll rate for comparasion.

300 (180): 144 (65) (P63: 88)
400 (250): 96 (75) (P63: 108)
500 (310): 72 (62) (P63: 90 est)

Did the P39N in reality roll much better than the D version? In FB is it more than double the roll rate
seen in the NACA report at 300km/h. The P63 has a much
better roll rate, though, so does the P39N have some
of the improvements that found their way onto the P63 included?



Message Edited on 08/17/0302:28PM by AaronGT

XyZspineZyX
08-17-2003, 04:00 PM
perhaps best way is e-mail oleg or ubisoft that

i have never hear that p39 was american best rollrate plane





Message Edited on 08/17/0307:09PM by Skalgrim

XyZspineZyX
08-17-2003, 11:08 PM
bump

XyZspineZyX
08-17-2003, 11:20 PM
AaronGT wrote:
- bump
- /i/smilies/16x16_smiley-wink.gif
-

I'l second that.

Anyway how can you now you pushed with the equivalent force? cuz here, the calibration of your stick plays a important role also. /i/smilies/16x16_smiley-indifferent.gif

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Message Edited on 08/18/0305:04AM by Von_Zero

XyZspineZyX
08-18-2003, 02:58 AM
There were no changes made in the P-39 from the D through N (or Q, for that matter) that would have had a significant impact on roll rate. The FB Cobra is seriously overmodeled.

-Bill

XyZspineZyX
08-18-2003, 03:42 AM
Luft!Whiners. Leave the P-39 ALONE. It Fine. it's the only good plane we have.

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XyZspineZyX
08-18-2003, 03:47 AM
One of the best articles I have read on the subject of IL2 FB FM's.

I'm sure all the FM/data "experts" in here have already read it, and dismissed it, but makes sense to me.



http://www.simhq.com/_air/air_065a.html

All the best, Don

XyZspineZyX
08-18-2003, 03:48 AM
Copperhead310th wrote:
- Luft!Whiners. Leave the P-39 ALONE. It Fine. it's
- the only good plane we have.
-
-

Seems apparent that in some quarters that "realism" is only valued if it increases the capabilities of US aircraft.
Over modelled US aircraft are fine though.

XyZspineZyX
08-18-2003, 04:45 AM
The P39 should roll pretty well..I don't have any numbers in front of me, but planes that are unstable on the roll axis (like the Fw and to some extent the P39) tend to roll well because they roll with little input..and usually at higher speeds, they still have the ability to defelecct the control surfacees..

XyZspineZyX
08-18-2003, 06:08 AM
It should a superb roll rate. The only problem is you'll never know when it's goning to happen to ya! SNAP ROLL that is.

XyZspineZyX
08-18-2003, 10:24 AM
Von_Zero wrote:
- Anyway how can you now you pushed with the
- equivalent force? cuz here, the calibration of your
- stick plays a important role also.

I tried different stick calibrations, in the game,
and in Windows. Made no difference to the roll rates
at all with full joystick deflection in the game.

The 50lb stick force is probably a maximum practicably
attainable, so that probably gives a maximum outlier
for the roll rate.

But the N isn't the D, so there might be differences
in the N to give a higher roll rate, hence my question.

XyZspineZyX
08-18-2003, 10:27 AM
Copperhead310th wrote:
- Luft!Whiners.

I'm not a Luftwhiner! I am in a VVS squad and
(except in training if we split into LW v VVS teams
to test tactics) fly VVS/allied planes almost
exclusively. I enjoy flying the P39, 40, and 47!

However, I want to see the P39N and Q roll as they
did historically.

Sadly, I also want to see the Tempest V, when we get
it, to roll at a historical rate too, even though it
means about the only thing it will outroll will be
the TB3!





Message Edited on 08/18/03 09:30AM by AaronGT

Message Edited on 08/18/0309:31AM by AaronGT

XyZspineZyX
08-18-2003, 10:29 AM
griego wrote:
- It should a superb roll rate.

The NACA tests of the P39D give it a fairly average
roll rate, but the P63 a superb roll rate.

XyZspineZyX
08-18-2003, 02:14 PM
I hear all these people online saying the p39 is so uber, they are all flying them online and blowing up 190s la5s online, saying only a p39 can shoot down a p39, i took my 109g14 against 3 p39s bnzing on them blew them all out of the sky a number of times with 1 shot, they dont seem too uber to me at all.

mig3u
190s

now theres some wrong rollrates


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XyZspineZyX
08-18-2003, 02:18 PM
They're only uber when they can land a 37mm shell on your wing. Much of that has to do with pilot ability.

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XyZspineZyX
08-18-2003, 03:18 PM
Well obviously if youre bnz them you have a serious advantage from the start.If youre talking about a1 that don't count.

XyZspineZyX
08-18-2003, 03:21 PM
see the p47 roll rate being off, and the 190 at high speeds roll rate being off...

it wouldn't surprise me if roll rates in general are 'off'

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XyZspineZyX
08-18-2003, 03:47 PM
Recon_609IAP wrote:
- see the p47 roll rate being off, and the 190 at high
- speeds roll rate being off...
-
- it wouldn't surprise me if roll rates in general are
- 'off'

It must be hard to get it right in a physics based model,
though. You have to put in the figures for various
parts of the airfoil - or this is how it works in Xplane
in which you have a plane creator to play with, or in
Fighter Squadron (SDOE), and then hope that it all comes
out right. Must be a nightmare to test and get it all
tweaked properly, and maybe this is what we are seeing?

Maybe this is why for the Next Sim, Oleg is suggesting
fewer aircraft - more chance to test enough and get it
all correct?

I might fire up Xplane tonight or tomorow and give the
P51 a run through to see how it compares to the NACA figures.
It needs a ton of trim in XPlane just to get it in the air!

Zayets
08-18-2003, 03:49 PM
I don't understand numbers /i/smilies/16x16_smiley-sad.gif


Zayets out

XyZspineZyX
08-18-2003, 04:10 PM
LeadSpitter_ wrote:
- I hear all these people online saying the p39 is so
- uber, they are all flying them online and blowing up
- 190s la5s online, saying only a p39 can shoot down a
- p39, i took my 109g14 against 3 p39s bnzing on them
- blew them all out of the sky a number of times with
- 1 shot, they dont seem too uber to me at all.
-
- mig3u
- 190s
-
- now theres some wrong rollrates



Absolutely.
The point still remains that if they put roll, climb, stall, and any other rates (they want to pull out of their arse) to the side the fact still remains that it's easier to kill and survive online with several other planes (Yaks for one). So is the P-39 really that uber? I don't think so fellas.






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XyZspineZyX
08-18-2003, 06:50 PM
The FB P-39 rolls nearly twice as fast as the actual NACA data on the P-39D show (138d/s in my tests) compared to NACA's 75d/s. There were NO changes in P-39 construction that would account for a significant increase in roll rate.

The FB P-40M rolls a measly 48d/s compared to 95d/s for the P-40F (Merlin engined P-40E/M - short AND long tailed variants).

So we have the FB P-39 rolling 43d/s FASTER than the P-40M when in reality it should be 20d/s SLOWER.

I did all my tests at the airspeeds shown on the NACA charts to provide peak roll rate.

My personal desire is that all the planes be ACCURATE. That's the appeal of sims for me. The P-40 is my favorite airplane and I still prefer to fly it EVEN though it's undermodeled. I feel like I'm cheating in a P-39 (which is my second favorite airplane).

Make it right. If you really love it, you'll fly it anyway.

-Bill

The_Blue_Devil
08-18-2003, 08:10 PM
Copperhead310th wrote:
- Luft!Whiners. Leave the P-39 ALONE. It Fine. it's
- the only good plane we have.
-
-
No it is incorrect.. The Old Iron Dawg was a rookie killer due to the stall factor. No it is gone and she is bada$$ just incorrect. I want the old IL2 Airacobra back..now that was a hard bird to learn but fun to fly.

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