Flight and damage model physics

[LukeFF]

Please post any issues about the flight and damage model physics here. Please note this topic is strictly for bug reports. Any off-topic banter will be removed at our discretion. Thank you!

[Red_Dragon]

I was surprised by how quickly Sabre machine guns tear off the wings of the Mig-15. I was surprised by the power.. I did a quick test. I chose a Mustang and fired a very short burst at the B29, in about 1/4 second. You might be surprised, but I knocked him down.   

Скрытый текст

 

 

I repeated the test, the pattern is the same. A very small number of hits is enough, white smoke appears a second later, and black smoke appears a few seconds later. After about 3 to 5 more seconds, a fire appears. It always appeared in my tests! Even if I fired a very short burst and hardly aimed.No matter how I shot, from any angle, just playing and making almost no effort, this huge B29 fell every time.. Is this normal? If so, I would like to use such machine guns in Il2 Great Battle 😉

Anyway, a huge thank you to everyone for developing the new IL-2. This new Il2 just blew my mind, and I can't stop flying on this amazing map! You guys rock! These planes and this map literally saved the genre for me!

Edited July 1 by Red_Dragon

[Dash,Polder]

The two are not comparable, these are M3, not one part was interchangeable between guns and neither was the ammo from an M3 safe to fire through an M2, much higher rates of fire and velocity was also higher.  They are not the same gun.  Try the Mustang, that one is, it has M2 guns.

[Red_Dragon]

A B-29 isn't made of paper.. and  it’s still just a .50 cal, not a 37mm cannon.. Correct me if I'm wrong, but isn't this bomder called the Superfortress?

Anyway, if you had looked at the screenshots attached to my first post, you would have seen that I was testing the .50 cals using the Mustang.

 

 

Edited June 27 by Red_Dragon

[Gunfreak]

Is the crazy spinns i see the F80s doing particularly realistic. I would assume if you did that in a real F80(seen somewhat similar but less extreme versions in the F86) i don't think you would ever recover the aircraft.  That stuff looks more like something you could do in a space sim with newtonion physics. Not a 1950s jet in atmosphere. If player are already gaming the physics after 2 days. I'm afraid online play might soon become some silly breaking physics meta game.

[Gavrick]

28.06.2026 в 00:01, Gunfreak сказал:

Is the crazy spinns i see the F80s doing particularly realistic.

What do you mean?

[Dash,Polder]

Keep in mind the F-80 was so stable with such good flying characteristics it's one of the few fighters ever converted and purposely used in mass as a basic primary jet pilot training aircraft after it served in front line combat, as the T-33.  Training USAF jet pilots for over two decades, and even more if one counts foreign air forces.

[Gunfreak]

7 hours ago, Gavrick said:

What do you mean?

They basically tumble and roll like this.

 

[Gavrick]

 

6 часов назад, Dash,Polder сказал:

Keep in mind the F-80 was so stable

This pilot cannot agree with that)

 

This is interview with real pilot for some MSFS version of T33. And he said many interesting things about how T-33 "stable and simple".

Another opinion:

"So with the T-Bird, I remember our first flight they said you know once you take it off the wings are going to rock back and forth because the controls are very sensitive"

Hopefully I'll get a chance later to put up some graphs that really show what the F‑80's stability is all about.

 

[Gavrick]

5 часов назад, Gunfreak сказал:

They basically tumble and roll like this.

What you are describing sounds like dynamic roll coupling. I'm not surprised the F‑80 can get into that — with that mass spread (especially full ammo or tip tanks), high roll rate, and high speed.

When I get a chance, I'll try to push the aircraft into that regime myself. But it would be great if you could demonstrate what you mean, though.

[Mark_Krieger]

I understand perfect flight models do not exist (at least with actual technology) and I think that in general, actual flight models are more detailed and better than in Great Battles, but at the moment I tested all the prop planes in different airfields and I noticed that they bump a lot during takeoff. I understand that IL-2 Korea airfields aren't totally flat, like in Great Battles or other sims and that is a really great improvement, but this must come with a better simulation of dumpers of the landing gear of the plane to avoid this excessive and unrealistic bumping. The F-51D is a clear example, but it happens too with Yak-9P, La-11, and IL-10. Don't know if it happens with jets too. I admit that I don't have data of the dumpers effectiveness of these planes and I'm talking just about sensations that I feel.

Another of the problems of Great Battles was that usually the breaks didn't have enough power. I haven't still tested this aspect enough, but my sensations at the moment is that generally they have more power when holding the already stopped plane compared to great Battles (improvement), but that they still lack power when landing. You can apply full breaking many times without risk of putting the nose on the ground or exploding the tires, when in reality you should brake with care, usually.

Another difference I noticed is that rudder control is quite more difficult now when attacking at the ground compared to Great Battles. Rudder input tends to overreact, so I tend to do esses overcompensating. Don't know if that's more realistic or not, because I never flied any of those planes, but ground attacking in a precise way is much more difficult now.

 

  

Edited July 22 by Mark_Krieger
Snap rolls in F-51 was a forbidden maneuver

[uumembwa]

Some physics bug?😂🙃

 

[Juri_JS]

After the latest update the engines of AI Yak-9P pilots suddenly fail. Devs, you can check this in the attached mission.

Yak_9P_mission.zip

[GrumpyGnome]

I have had this happen also. I get a tecno readout that states "Fuel Starvation". The gauges on the wing read 200L and the "System menu" displays a red engine. Has also occurred just after takeoff. 

[AEthelraedUnraed]

28 minutes ago, GrumpyGnome said:

I have had this happen also. I get a tecno readout that states "Fuel Starvation". The gauges on the wing read 200L and the "System menu" displays a red engine. Has also occurred just after takeoff. 

I have had a "fuel starvation" message as well, in both the Yak and the P-80, but just for short moments and never long enough to stall the engine. I wasn't doing any negative G manoeuvres or similar. In the P-80, it continuously appeared then disappeared for something like 2 minutes total. Not sure if that's a bug, or if I was doing anything wrong?

[Juri_JS]

Is it just me or is the B-29 much to easy to shoot down? With the Yak-9P I can destroy it with just the UB machine guns. It seems engines catch fire after just a single hit. 

[FuriousMeow]

F51's combat time is half of what is listed. 3k RPM @ 61MP I get 7.5 minutes of flight before engine stutters and dies - and I was at 60mp. Either regular or 150 fuel. Full or run mix no difference. Temp gets to edge of green but doesn't get to red. And taking off at 3k @ 60mp the temps climb into the red before backing to green - winter or spring map appears the same in that aspect - but that indicates it isn't temp causing the engine death.  

Should be 15 minutes according to the in-game flight manual. 

This is level flight, playing with trim to keep as straight as possible with a few slow turns. 

Unless I'm missing something?

Edited July 4 by FuriousMeow

[Tuna_Lead]

Is it redundant to post FM issues here that we already posted in the Discord bug-reports-il2korea channel of the IL-2 Series Community discord?

[Tuna_Lead]

My above post is pertaining to the F-84E's flight model. I have not seen any activity on the discord post so I will just post it here, as this seems to be the correct place. 
I'll "spoiler" it so it does not take up too much room.
The problem is response to G load at redline mach. It should be destructive.

 

Spoiler

Hello,
in "Handbook, Flight Operating Instructions, USAF SERIES F-84E AIRCRAFT" (AN 01-65BJC-1)
Page 27, paragraph 2-36 states:
"Below 15,000 any speed which is above red line airspeed (.82 Mach number) can have disastrous results. When more than 1G is placed on the airplane at close to the critical Mach number which is red line airspeed, the change in the angle of attack lowers the critical Mach number and a violent pitch-up occurs under 15,000 feet. The pitch-up G's combined with those already imposed by you can result in exceeding the design load limit of the airplane particularly if you are in a dive which is steep enough to maintain or increase the speed."

Apparently this is a consistent behavior, according to "Higham, Robin; Siddall, Abigail T., eds. (1975). Flying Combat Aircraft of the USAAF-USAF. Ames, Iowa: Iowa State University Press. ISBN 0-8138-0325-X." it was employed in combat, risking loss of the aircraft. 

In the same Flight Operating Instructions, but on page 28 and 28A there are graphs displaying the regions in which pitch up occurs.

I have been able to exceed 600 mph at 5000 feet, beyond the mach for the 1g limit, and exceed 3gs without separating my wings. In fact, in a steep dive from 10,000 feet, you can well exceed all of those metrics and pull out of the dive as violently as possible (using trim) and still have your wings and a functioning aircraft.

Steps to reproduce this:

Task editor > Free flight > F-84 with full fuel load. Start at 10000 feet.
Spawn in. Trim full nose up, using the stick to level yourself. (to give max pull out authority)

Nose down 70-80 degrees. Any harsh dive will do.

Dive until your speedometer's mach window exceeds 0.85. Through the shaking, you can make out you can handily reach 0.9. before being too low to do this. 

When the altimeter indicates 5,000 feet, glance and verify your speed is exceeding mach 0.85.

Rip the stick backwards. 
Record max G. Compare the speed, altitude, and G combination to the flight operating instruction handbook as listed above.

By all of the manual's warnings and historical accounts your wings should separate from the aircraft as it violently pitches up, ripping itself apart. You should find even with a full fuel and ammo load you will survive this maneuver if you do it over the ocean at 5000 feet. 

My recommendation to fix this:
The aircraft should experience a sudden, uncommanded pitch up when exceeding the limitations of the curves on the chart "Effect of altitude on V.G. Diagram (Indicated Airspeed) on page 28A of "Handbook, Flight Operating Instructions, USAF SERIES F-84E AIRCRAFT" (AN 01-65BJC-1). This pitch up should physically remove the wings from the aircraft.

System Specs:
CPU : Ryzen 7950X3D
GPU : 5070TI
Ram:  96GB
VR Headset: Quest 3
Peripherals: T16000M HOTAS with pedals

Thank you for your time. I will have to rely on the developers to already have the Flight Operating Instructions for the F-84E as the copy I have is a scan that was purchased, and forbids reproduction of the scans (and therefore the charts I would attach if it was not the case). The words, however, are obviously not copywritten.

 

Edited July 5 by Tuna_Lead

[LukeFF]

On 7/3/2026 at 9:24 AM, Juri_JS said:

Is it just me or is the B-29 much to easy to shoot down? With the Yak-9P I can destroy it with just the UB machine guns. It seems engines catch fire after just a single hit. 

It is planned to have some DM updates to the B-29 in the next public release.

[pr0x]

In the Mig-15, the fuel gauge does not update after a fuel leak. I get the "10 minute or less of fuel" warning with the gauge still showing close to full.

[Kareem]

An airplane is unlikely to be able to rely on a propeller blade like that. The propeller must either turn or bend. Even the tail is broken, but the propeller blade is intact...

[ZYSS]

Take the La-11 and F-51D as examples: with the game’s default 3 m/s crosswind from the left on ground, and with the tailwheel unlocked, the aircraft requires constant braking just to maintain directional control during taxi. Even with the tailwheel locked, I still need frequent brake taps to keep it straight.

A wind speed of 3 m/s is only a Force‑2 light breeze. If such a low wind speed can have such a big impact on the aircraft’s directional control during taxiing, is the plane made of paper?

Would pilots really need to use brakes so often under such conditions in real?

[BlitzPig_EL]

I have a small convoy of US ships steaming at 10 knots.  2 Gleaves DMSs, 1 Liberty ship, and 1 LST.

Attacking them with the IL10 I can easily sink the Gleaves and the Liberty ship, but the LST can absorb damage like a battleship.  I hit it with four pairs of FAB 250s and numerous of the larger Russian rockets, to no avail.  No smoke, no fires, nothing.  I also tried a Kamikaze attack and nothing happened to the LST. 

[pr0x]

I know the Yak is bugged due to a fuel mixture issue, but even with the correct fuel mixture the Yak seems to randomly shut down its engine. Yak bugs seem to happen much more frequently on multiplayer servers - I wonder if this maybe has something to do with AI helpers being enforced on these servers?

Edited July 13 by reidarpeidar