PDA

View Full Version : P-39 & P-40 Roll Rates



XyZspineZyX
08-26-2003, 06:04 PM
Now that Oleg has agreed to correct the P-47's roll rate, how about the two remaining US pursuits? The P-39 rolls nearly twice as fast as it should, and the P-40 is significantly slower than it should be. The P-40 SHOULD out-roll the P-39.

I don't know about any of the other planes in FB, but my vote says make them all as correct as can be based on the available data.

This performance characteristic makes a huge difference in how these planes are used tactically, and severely affects the realism of FB as a combat sim.

If I was to prioritize software updates it would go like this:

1. Fix any outstanding bugs affecting software stability.

2. Correct individual aircraft performance and handling characteristics when substantiating data becomes available.

3. Add features/improve eye candy.


-Bill

XyZspineZyX
08-26-2003, 06:04 PM
Now that Oleg has agreed to correct the P-47's roll rate, how about the two remaining US pursuits? The P-39 rolls nearly twice as fast as it should, and the P-40 is significantly slower than it should be. The P-40 SHOULD out-roll the P-39.

I don't know about any of the other planes in FB, but my vote says make them all as correct as can be based on the available data.

This performance characteristic makes a huge difference in how these planes are used tactically, and severely affects the realism of FB as a combat sim.

If I was to prioritize software updates it would go like this:

1. Fix any outstanding bugs affecting software stability.

2. Correct individual aircraft performance and handling characteristics when substantiating data becomes available.

3. Add features/improve eye candy.


-Bill

XyZspineZyX
08-26-2003, 06:13 PM
And the Fw-190 rolls WAY too fast at high speeds, 3 second rolls at 863 km/h.

And the Bf-109F-K rolls too fast, too.

Regards,

SkyChimp

http://members.cox.net/rowlandparks/tiger.jpg

XyZspineZyX
08-26-2003, 08:59 PM
SkyChimp wrote:
-
- And the Bf-109F-K rolls too fast, too.


Details, please.

http://vo101isegrim.piranho.com/FB-desktopweb.jpg
'Only a dead Indianer is a good Indianer!'

Vezérünk a Bátorság, K*sérµnk a Szerencse!
(Courage leads, Luck escorts us! - Historical motto of the 101st Puma Fighter Regiment)

Flight tests and other aviation performance data: http://www.pbase.com/isegrim

XyZspineZyX
08-26-2003, 09:49 PM
I knew the P-39 was a bit overmodeled on the roll rates in some situations and P-47 was a bit undermodeled but I wasn't aware there was a problem with the P-40...it rolls as quickly as any of the footage I've seen with P-40's...not that thats a scientific representation...it just seems right.

http://freespace.volitionwatch.com/icefire/icefire_tempest.jpg
"Never in the field of human conflict was so much owed by so many to so few." - Winston Churchill

XyZspineZyX
08-26-2003, 09:54 PM
Please fix all of the roll-rates that require one. /i/smilies/16x16_smiley-happy.gif

The P-39 does seem to roll very fast.

Slow the 190's roll-rate down at speed if that is accurate, just please let it retain energy as it does now and not be the flying brick (along with P-47) that it was before.

And please look at the P-40's top speed. Some say it is WAY slower than it should be and never approaches its top speed.

<center>
http://www.brooksart.com/Icewarriors.jpg

"Ice Warriors", by Nicolas Trudgian.

Message Edited on 08/26/03 08:55PM by kyrule2

Message Edited on 08/26/0308:57PM by kyrule2

XyZspineZyX
08-26-2003, 10:17 PM
"it just seems right"

wow - how would you know that?

otherwise - i've seen enough discrepancies with the data shown to say that roll rates in general need a look at!

S!
609IAP_Recon

Forgotten Wars Virtual War
Forum: http://fogwar.luftwaffe.net/forums/index.php
Website: http://forgottenwars.dyndns.org
Visit 609IAP at http://takeoff.to/609IAP

http://www.leeboats.com/609/sig/609_recon3.jpg

Agnus Dei, Qui Tollis peccata mundi, Miserere nobis. Dona nobis pacem

XyZspineZyX
08-27-2003, 12:06 AM
yes I would love the 190s roll rate to be fixed. I havent had too much problem getting the P40 going pretty fast since the patch, but I havent recorded details so I am not saying its wrong or right now.


"Ich bin ein Wuergerwhiner"

"The future battle on the ground will be preceded by battle in the air. This will determine which of the contestants has to suffer operational and tactical disadvantages and be forced throughout the battle into adoption compromise solutions." --Erwin Rommel

http://lbhskier37.freeservers.com/Mesig.jpg
--NJG26_Killa--

XyZspineZyX
08-27-2003, 02:20 AM
Vo101_Isegrim wrote:
-
- SkyChimp wrote:
--
-- And the Bf-109F-K rolls too fast, too.
-
-
- Details, please.


Example:

Bf-109G-6 WITH Mk108 gunpods.

All rolls at 2,000 meters
All speeds at TAS

3 second roll @ 350 km/h
3.5 second roll @ 400 km/h
4 second roll @ 450 km/h

Regards,

SkyChimp

http://members.cox.net/rowlandparks/tiger.jpg

XyZspineZyX
08-27-2003, 03:18 AM
P-40 is still slower than it should be... it can never get even close to its top speed at any altitude. Best I ever got this bird to keep in level flight is about 290mph.

Roll rate is indeed way to slow for higher speeds as P-40 aerlon surfaces are small and it should roll faster at higher speeds than slower...and in FB this is opposite. Anything faster than 300mph and P-40 starts rolling like a He-111 or even slower. P-40 should roll badly at slow speeds and roll excellent at high speeds.

XyZspineZyX
08-27-2003, 05:16 AM
The NACA data for roll rates is fairly conclusive. The P-40 was one of the fastest rolling US planes of the war.

http://naca.larc.nasa.gov/reports/1947/naca-report-868/index.cgi?thumbnail1#start


-Bill

XyZspineZyX
08-27-2003, 08:58 AM
also the p40s torque and level flight speeds are well below the norm for the E and the M model, also the p40 e should be the one that stalls easier the M model fixed that problem, and the nose over the e had.

thats why the M model has the longer rudder and elevators

http://ubbxforums.ubi.com/infopop/emoticons/icon_wink.gif

the 190 yak3 p39 and mig3 need major dulling of the control sensativity and the 190 is the best rolling a/c in the charts but in fb its so unrealistic looking and the manuevers it can pull off make me think of cfs2 modded planes. also the roll tests are rolling one way you cant make an immediate opposite roll or bank at the same speed.

the b1 needs some major dulling as well. other then that 1.1b is pretty great.

I just hope oleg decides to check out fms online to see the moves and exploits all of us are using in the p39 yaks 190s and mig3u.



http://mysite.verizon.net/vze4jz7i/ls.gif

Good dogfighters bring ammo home, Great ones don't. (c) Leadspitter



Message Edited on 08/27/03 08:07AM by LeadSpitter_

Message Edited on 08/27/0308:09AM by LeadSpitter_

XyZspineZyX
08-27-2003, 10:09 AM
Yes please fix the roll rate,I could almost live with the slow speed if I had a better roll rate.

No1RAAF_Pourshot


http://members.optusnet.com.au/~andycarroll68/CAC-15.jpg

CAC CA-15 Kangaroo

XyZspineZyX
08-27-2003, 07:58 PM
SkyChimp wrote:
- And the Fw-190 rolls WAY too fast at high speeds, 3
- second rolls at 863 km/h.

Start a thread on the 190 then!

XyZspineZyX
08-28-2003, 02:05 AM
AaronGT wrote:
-
- SkyChimp wrote:
-- And the Fw-190 rolls WAY too fast at high speeds, 3
-- second rolls at 863 km/h.
-
- Start a thread on the 190 then!
-
-
-
-
-

Been done.

Regards,

SkyChimp

http://members.cox.net/rowlandparks/corsairs.jpg

XyZspineZyX
08-28-2003, 02:56 AM
Salute

The P-40 rollrate is low.

Here is a comprehensive set of tests of the P-40F done by NACA:

http://mitglied.lycos.de/luftwaffe1/aircraft/usaaf/P40F_aileron.pdf

Go to page 29 for the Degrees per second rollrate chart.


RAF74 Buzzsaw

XyZspineZyX
08-28-2003, 02:58 AM
Salute

By the way, although the speed and rollrate of the P-40's are low, their climbrate is a bit too high.


RAF74 Buzzsaw

XyZspineZyX
08-28-2003, 12:45 PM
My best TAS in the P40E is 325mph @ 15,000ft. This is about 35MPH too slow....

And the roll rate for the newer versions was less than the early birds, but the worst ones were still 90 deg./sec.

<center><FONT color="red">[b]BlitzPig_EL</FONT>[B]<CENTER> http://old.jccc.net/~droberts/p40/images/p40home.gif
</img>.
"All men dream, but not equally. Those who dream by night in the dusty recesses of their minds, wake in the day that it was vanity:
but the dreamers of the day are dangerous men, for they may act on their dreams with open eyes, to make them possible. "
--T.E. Lawrence

XyZspineZyX
08-29-2003, 04:40 AM
RAF74BuzzsawXO wrote:
- Salute
-
- By the way, although the speed and rollrate of the
- P-40's are low, their climbrate is a bit too high.

In FB best sustained climb rate is about 2000ft/min...what does reliable info on P-40 climb rate says???

XyZspineZyX
08-29-2003, 05:08 AM
No.1RAAF_edin wrote:

- In FB best sustained climb rate is about
- 2000ft/min...what does reliable info on P-40 climb
- rate says???



2,000 fpm is too low and that's about what I get.

Climb for any P-40 model was poor at best. For the P-40K, climb rate at MILITARY POWER was about 2,000 fpm @ SL, 2,200 fpm @ 5,000 feet, 2,350 @ 10,000 feet, 1,750 @ 15,000 feet.


COMBAT POWER will increase rate of climb but I don't have a chart.

BTW, the P-40E should climb pretty closely inline with the P-40K.

AHT does have a "time to climb" chart for early American fighters on NORMAL POWER. Combat power rates-of-climb and times-to-climb will have to be extrapolated:

http://members.cox.net/rowlandparks/climb_earlyarmy.jpg



Regards,

SkyChimp

http://members.cox.net/rowlandparks/corsairs.jpg


Message Edited on 08/29/0308:19AM by SkyChimp

XyZspineZyX
08-29-2003, 05:23 AM
Best info I have says 2,067ft/min for both the P-40E and P-40M. The K is listed as 2,017ft/min, which makes sense because it was heavier. For comparison's sake, the Merlin-engined F-5 and L-5 are listed as 3,277 and 3,327 respectively. The N-20 is 2,136.

-Bill

XyZspineZyX
08-29-2003, 05:47 AM
hawkmeister wrote:
- Best info I have says 2,067ft/min for both the P-40E
- and P-40M. The K is listed as 2,017ft/min, which
- makes sense because it was heavier. For
- comparison's sake, the Merlin-engined F-5 and L-5
- are listed as 3,277 and 3,327 respectively. The
- N-20 is 2,136.
-
--Bill
-
-

Bill,

Does your source say what the power rating and altiude is for the E and M?

I think the K's climb would be a fairly good basis for modelling the E and M. The gross weight of the K was 8,522 lbs. The gross weight of the E was 8,290, but the K had a little more power. The Gross weight of the M was 8,541. I'd think differences in climb would be pretty inconsequential.

Regards,

SkyChimp

http://members.cox.net/rowlandparks/corsairs.jpg

XyZspineZyX
08-29-2003, 06:04 AM
It doesn't specify, but I'd assume full military power.

As for weights - I don't like to go by gross weight because that's the maximum the plane is rated to weigh. It includes things like external ordnance, etc. I prefer to go by empty weight when comparing planes. That way you add the weight of the pilot, fuel, and ammo and you get a more accurate reflection of the plane's weight in combat.

The empty weights and rated hp are as follows:

E - 2,686 kg, 5,922 lb, 1,150 hp (V-1710-39)
K - 2,903 kg, 6,400 lb, 1,350 hp (V-1710-73)
M - 2,940 kg, 6,482 lb, 1,350 hp (V-1710-73)
N - 2,812 kg, 6,199 lb, 1,200 hp (V-1710-99)

-Bill

XyZspineZyX
08-29-2003, 06:22 AM
hawkmeister wrote:
- I don't like to go by gross weight
- because that's the maximum the plane
- is rated to weigh. It includes things
- like external ordnance, etc.
- ...
- The empty weights and rated hp are as follows:
-
- E - 2,686 kg, 5,922 lb, 1,150 hp (V-1710-39)
- K - 2,903 kg, 6,400 lb, 1,350 hp (V-1710-73)
- M - 2,940 kg, 6,482 lb, 1,350 hp (V-1710-73)
- N - 2,812 kg, 6,199 lb, 1,200 hp (V-1710-99)
-
--Bill
-
-


The gross weights I offered were equal to the basic weights plus useable disposeable loads (pilot, useable oil, internal fuel and full .50 cal ammo (no external stores)). This provides a weight for a P-40 in clean fighter configuration.

At any rate, my sources show very similar empty weights, but different engines for all three:

E - 6,069 lbs
=============
V-1710-39/F3R
T.O 1,150 hp
W.E. 1,490 @ 56" MAP
Mil 1,150
Norm 1,000



K - 6,367 lbs
=============
V-1710-73/F4R
T.O. 1,325 hp
W.E. 1,580 @ 60" MAP
Mil 1,150
Norm 1,080



M - 6,386 lbs
==============
V-1710-81/F20R
T.O. 1,200
W.E 1,410 @ 57" MAP
Mil 1,125
Norm not listed for some odd reason




Regards,

SkyChimp

http://members.cox.net/rowlandparks/corsairs.jpg


Message Edited on 08/29/0310:56AM by SkyChimp

XyZspineZyX
08-29-2003, 08:09 AM
Your engine data is more detailed than that from my original reference. I double-checked the data on Joe Baugher's website and yours is more correct.

http://www.csd.uwo.ca/~pettypi/elevon/baugher_us/


There is a typo in his data on the M where he shows an "V-1710-18" instead of the -81.

For what it's worth, "Empty Weight" is a specific term that includes all fluids necessary for operation of the airplane except fuel. So if you added the weights of oil, hydraulic fluid, radiator fluid, etc., you essentially doubled those values.

-Bill

XyZspineZyX
08-29-2003, 10:13 AM
SkyChimp wrote:
-- Start a thread on the 190 then!
-
- Been done.

Good! It is just that if all planes get dragged
into a thread it seems to quickly degenerate into
a slanging match and nothing gets achieved. The P47
threads managed to stay relatively clean, and got
something done!

XyZspineZyX
08-29-2003, 10:16 AM
SkyChimp wrote:
- No.1RAAF_edin wrote:
-
-- In FB best sustained climb rate is about
-- 2000ft/min...what does reliable info on P-40 climb
-- rate says???
-
-
-
- 2,000 fpm is too low and that's about what I get.
-
-
-
- Climb for any P-40 model was poor at best. For the
- P-40K, climb rate at MILITARY POWER was about 2,000
- fpm @ SL, 2,200 fpm @ 5,000 feet, 2,350 @ 10,000
- feet, 1,750 @ 15,000 feet.


Question (I mentioned this in GD too).

Is Oleg modelling the P40 based on USAAF data, with
decent fuel, or based on Russian data, with lower
octane typical Soviet fuel? The latter would mean
a lower HP rating for military power.

If there are charts showing the typical HP developed
in the Allison with lower octane fuel, and charts
showing climb for particular HP ratings, then we might
be able to do a more direct comparasion of the P40
in the game, with that of reality.

I am just wondering, though, if Oleg is basing the
performance on the results the USSR got with low
octane fuel. Or it could just as easily be a bug, of
course!

XyZspineZyX
08-29-2003, 03:40 PM
hawkmeister wrote:

- For what it's worth, "Empty Weight" is a specific
- term that includes all fluids necessary for
- operation of the airplane except fuel. So if you
- added the weights of oil, hydraulic fluid, radiator
- fluid, etc., you essentially doubled those values.
-
--Bill


I used the "basic weight" and added the the "Total Disposable Load" to get to the Gross weight.

The "basic weight" of the aircraft is determined by taking the "empty weight" and adding such things as:

trapped oil

trapped fuel (in this case zero)

.50 cal gun installation

gunsight (if added in addition to basic crosshair sites)

armor/BP Glass (unless already included in empty weight (which it is on the E, K and M))

pyrotechnics (in this case zero)

Oxygen Equipment (in this case zero)



Regards,

SkyChimp

http://members.cox.net/rowlandparks/corsairs.jpg

XyZspineZyX
08-29-2003, 03:42 PM
AaronGT wrote:
-
- SkyChimp wrote:

- Question (I mentioned this in GD too).
-
- Is Oleg modelling the P40 based on USAAF data, with
- decent fuel, or based on Russian data, with lower
- octane typical Soviet fuel? The latter would mean
- a lower HP rating for military power.
-
- If there are charts showing the typical HP developed
- in the Allison with lower octane fuel, and charts
- showing climb for particular HP ratings, then we
- might
- be able to do a more direct comparasion of the P40
- in the game, with that of reality.
-
- I am just wondering, though, if Oleg is basing the
- performance on the results the USSR got with low
- octane fuel. Or it could just as easily be a bug, of
-
-
- course!


This has been brought up before, but quite a long time ago (IL2 days I think). Oleg has stated that he models US planes based on their performance on US aviation fuel. The reason is becasue in addition to planes, the Soviets got huge qunatities of US fuel to run them on.



Regards,

SkyChimp

http://members.cox.net/rowlandparks/corsairs.jpg

XyZspineZyX
08-29-2003, 10:05 PM
A USAAF evaluation of the P-40E(weight unknown) with the 109F-4 gives a time of climb to 15,000ft. for the P-40 as 7.2 minutes. That would be about 2083 ft/min.




<center><img src= "http://www.luftwaffepics.com/LCBW4/FW190-A0-52.jpg" height=215 width=365>

<center>"We are now in a position of inferiority...There is no doubt in my mind, nor in the minds of my fighter pilots, that the FW190 is the best all-round fighter in the world today."

Sholto Douglas, 17 July 1942

XyZspineZyX
08-29-2003, 10:37 PM
SkyChimp wrote:
- This has been brought up before, but quite a long
- time ago (IL2 days I think). Oleg has stated that
- he models US planes based on their performance on US
- aviation fuel. The reason is becasue in addition to
- planes, the Soviets got huge qunatities of US fuel
- to run them on.

Fair enough. That means that comparasion of in game
results to USAAF performance figures is fair, then.
I wasn't sure what data Oleg had used, hence the
question.

Thanks

XyZspineZyX
08-30-2003, 12:31 AM
I think the more pertinent problem with the P-39 is the fact that it can't elevator stall in game. Sure, the roll rate is on crack at the moment, but what fun is the P-39 if it isn't stalling like it should?