Flight and damage models physics

[Sitaro]

I think it is safe to say the dm is really flawed and the 47 gets really hosed compared to many others. Not sure why it would take less hits to get higher damage values. 

[Roland_HUNter]

Nice dmg modell on that P-38

 

[357th_KW]

8 hours ago, Roland_HUNter said:

Nice dmg modell on that P-38

 

Looks a heck of a lot more reasonable then the P-38 at 7:20 of that same video.

[Roland_HUNter]

26 minutes ago, 357th_KW said:

Looks a heck of a lot more reasonable then the P-38 at 7:20 of that same video.

You really mean, take dozens of 20mm, 2xfire extinguishing is less broken than 1 boom?
Wow....

[357th_KW]

23 minutes ago, Roland_HUNter said:

You really mean, take dozens of 20mm, 2xfire extinguishing is less broken than 1 boom?
Wow....

 

15 x 20mm HE and 1 x 30mm HE, plus a bunch of AP.  And the P-38 was crippled almost immediately and ultimately went down.  Is it an outlier?  Sure.  Is it wildly unrealistic?  Not at all.  We know of historical cases where allied aircraft returned to base after taking dozens of cannon hits - clearly this was a possible outcome.

 

We know from US testing after the war, that a single 20mm Hispano HE hit only had about a 6% chance of producing an immediate kill on a P-47.  10 random hits only raised that about 50%.  Given those percentages, you could easily get a result where dozens of HE shells might be necessary.  In game we're seeing about 4-5 HE hits plus some AP is the average.  Keep in mind that plenty of our in game kills get hit with significantly more then what it actual took to score the kill, with multiple attackers trying to steal kills from each other.  The P-38s durability is right in the same ballpark in game.

 

As far as the instant explosions that rip the entire airframe apart - please find an example in some historic gun camera footage - I haven't found a single one yet.  What you see is that most of it looks more like that P-38 at the 21:00 mark.

 

 

 

 

 

[CountZero]

1 hour ago, Roland_HUNter said:

You really mean, take dozens of 20mm, 2xfire extinguishing is less broken than 1 boom?
Wow....

or its maybe broken net code in MP, you seam to understand that in his mosquito vs indistructable 109 video, its not DM then but net code, but here when allied airplane eats led ,his DM is broken , it can ot be anything els, on same server with same broken net code we have last few years... if airplanes online eat planty hitts its mostly bullet info lost and not recived/transmited. Test in SP if you think something is broken with DM, if its in MP you cant know whats broken as net code is mess on highly demanding servers like VP is.

Edited July 5, 2022 by CountZero

[Thales]

Brief description: The "bomb load" modification for the Fw 190 G-3 and Fw 190 G-3/R-5 seems to apply the properties of the underbelly ETC 501 bomb rack a second time.

 

Detailed description, conditions:

 

Selecting the "Fw 190 G-3" or "Fw 190 G-3/R-5" fighter bomber modification of the Fw 190 A-6 adds both underwing bomb racks and an underbelly ETC 501 bomb rack (without any bombs), leading to a corresponding reduction in top speed.

 

Combining the G-3 or G-3/R-5 with the "bomb load" modification (to actually equip bombs) seems to apply the drag and weight of the underbelly ETC 501 bomb rack a second time, leading to a further reduction in top speed even after all bombs have been dropped.

 

This can be easily verified: The difference in sea level top speed between a G-3 starting without bombs and a G-3 after equipping and dropping an SC 250 bomb is about 13 km/h even though the outward appearance of the aircraft is exactly the same in both cases.

[Hitcher]

Brief description:

Spitfire (all versions) becomes extremely difficult to fly with damage to horizontal stabilizers/elevators compared to all other fighters in game.
 

Detailed description, conditions:

With damage to the horizontal stabilizer all versions of the spitfire become extremely difficult to fly level in contrast to other fighters.

A single hit from high explosive shells (12.7mm, 13mm, 20mm) to the horizontal stabilizer are sufficient to dramatically destabilize the aircraft and cause a flat spin/inverted flat spin if close attention to the controls isn't applied.

Other fighters don't have this issue, there is added instability in other cases however the aircraft can still fly level with minimal effort and even perform advanced manoeuvres in most cases.

 

I conducted my tests with a modded service pistol that shoots German 20mm HE shells into the horizontal stabilisers of random fighters and recorded the results.

I measured each aircrafts ability to maintain auto level and removed 1 stabiliser each for consistency in my testing.

These tests showed that with 1 stabilizer all aircraft except the 3 available models of spitfire could maintain auto level; the spitfire would rapidly nose up or down and enter a flat spin without immediate correctional inputs from the pilot.

 

I have attached clips and track files of all aircraft tested.

 

Additional assets (videos, screenshots, logs):

 

Spitfire Mk XIV:

https://gfycat.com/ambitioussizzlingarawana

spitXIV_hori_stab_test.rar

 

Spitfire Mk IX:

https://gfycat.com/bravescientificaurochs

https://gfycat.com/rewardingspitefulandalusianhorse

spitIX_hori_stab_test.rar

spitIX_hori_stab_test_2.rar

 

Spitfire Mk V:

https://gfycat.com/forthrightperfumedleafbird

https://gfycat.com/potableunfitislandwhistler

https://gfycat.com/livelypoliticalamericancreamdraft

spitV_hori_stab_test.rar

spitV_hori_stab_test_2.rar

spitV_hori_stab_test_3.rar

 

Typhoon:

https://gfycat.com/queasyregaljackrabbit

typhoon_hori_stab_test.rar

 

Tempest:

https://gfycat.com/impressionabledearchihuahua

tempest_hori_stab_test.rar

 

P47 D28:

https://gfycat.com/mellowweepyflyingfox

d28_hori_stab_test.rar

 

P51D:

https://gfycat.com/generouswholekusimanse

p51_hori_stab_test.rar

 

BF109 K4:

https://gfycat.com/ickymeeklaughingthrush

k4_hori_stab_test.rar

 

BF109 G14:

https://gfycat.com/opulenttatteredbedlingtonterrier

g14_hori_stab_test.rar

 

FW190 A8:

https://gfycat.com/carefreegoodnaturedhammerheadbird

a8_hori_stab_test.rar

 

FW190 D9:
https://gfycat.com/soggyimaginativeharrier

d9_hori_stab_test.rar

 

I'd be happy to provide additional assets.

[-DED-Rapidus]

On 7/15/2022 at 11:36 PM, Hitcher said:

Brief description:

Spitfire (all versions) becomes extremely difficult to fly with damage to horizontal stabilizers/elevators compared to all other fighters in game.

There was already a report about a similar problem earlier, engineers checked and it turned out to be a feature of spitfires. I'll check with the engineers again, maybe something has changed. The problem occurred after the update or has it been a long time?

[Hitcher]

8 hours ago, -DED-Rapidus said:

There was already a report about a similar problem earlier, engineers checked and it turned out to be a feature of spitfires. I'll check with the engineers again, maybe something has changed. The problem occurred after the update or has it been a long time?

Thanks for the reply Rapidus, perhaps the behaviour is correct in the case of a missing horizontal stabilizer.

I did a quick test of the p51 under the same conditions with full auxiliary fuel and observed similar results to the spitfire.

 

I suspect the problem could be how much skin damage high explosive shells are creating per shell.

 

The below image is the result of 1 20mm shell impact to the left stabiliser, as you can see the damage has extended to the other stabilizer as well as the rudder which could be effecting controllability excessively.

 

You and the team are probably aware of the overperformance of HE shells in the current version of the game so I wont revisit that topic again.

 

To answer your question this has been the case for a long time.

 

 

Additional testing:

 

After some testing it seems current HE modelling is most likely the culprit for this behaviour.

 

I modified the radius of the German 20mm shell from its original 5.7m to 0.57m so I could isolate damage to 1 stabilizer and recorded the results.

 

Original radius 5.7m:

spirfire_test_original_radius_5.7.rar

https://gfycat.com/terribleoptimalharlequinbug

 

Modified radius 0.57m:

spitfire_test_modified_radius_0.57.rar

https://gfycat.com/highlevelastonishinggrasshopper

 

From these clips/tracks you can observe the modified HE shell (reduced radius to 0.57) damage only effecting 1 control surface allowing the AI to maintain auto level.

From the original shell (radius 5.7) the damage is spread to all controls in the tail thus rendering the aircraft incredibly difficult to control with the AI unable to maintain level flight.

 

It seems more reasonable that a 20mm shell would most likely effect one control surface with very limited damage to other structures, in this case the rudder/vertical stabilizer.

 

Thanks.

Edited July 18, 2022 by Hitcher
Added additional assets

[357th_KW]

On 7/18/2022 at 5:31 AM, Hitcher said:

You and the team are probably aware of the overperformance of HE shells in the current version of the game so I wont revisit that topic again.

 

To answer your question this has been the case for a long time.

 

Additional testing:

 

After some testing it seems current HE modelling is most likely the culprit for this behaviour.

 

I modified the radius of the German 20mm shell from its original 5.7m to 0.57m so I could isolate damage to 1 stabilizer and recorded the results.

.

Just to add to this, I have to highlight that the current damage radius of an MG151/20mm HE is 5.7m!  That’s practically the entire airplane!  We can see in tests of the much larger MK108 shell (which had 4x the explosive of the 20mm mine shell and 20x the eplosive of the HEI and HE-T shells) that the damage radius is much smaller then this.  5.7 meters for the smaller 20mm shells in much too large.

 

 

[69th_Mobile_BBQ]

22 hours ago, 357th_KW said:

Just to add to this, I have to highlight that the current damage radius of an MG151/20mm HE is 5.7m!  That’s practically the entire airplane!  We can see in tests of the much larger MK108 shell (which had 4x the explosive of the 20mm mine shell and 20x the eplosive of the HEI and HE-T shells) that the damage radius is much smaller then this.  5.7 meters for the smaller 20mm shells in much too large.

 

 

 

That could explain why getting hit around the first 1/3 of a wing from the wing root or 1/3 down the spine from behind the pilot seat of an aircraft 1-shots the pilot so often.

 

[LukeFF]

There is an issue with War Emergency power on the P-39: according to the Specification page, 3000 rpm and 60 inHg should only be possible by having the fuel mixture lever in the Emergency Full Rich position. However, right now, 3000 rpm and 60 inHg can be attained with the fuel mixture lever in the Auto Rich position.

[354thFG_Panda_]

On 7/30/2022 at 5:44 PM, LukeFF said:

There is an issue with War Emergency power on the P-39: according to the Specification page, 3000 rpm and 60 inHg should only be possible by having the fuel mixture lever in the Emergency Full Rich position. However, right now, 3000 rpm and 60 inHg can be attained with the fuel mixture lever in the Auto Rich position.

Perhaps it is related to cooling performance? In game the 39 gets toasty at that power and overheats past the timer unless full mix is used.

Edited August 1, 2022 by theRedPanda

[354thFG_Panda_]

Brief description: 

Velocity dial on the Messerschmitt 410 in the cockpit is displaying a speed lower than it is actually flying unlike all aircraft in the simulator.

 

Detailed description, conditions: 

I have attached 3 instances to show the discrepancy. Gameplay wise it makes climbing this aircraft at a particular speed misleading and diving near the Vne Dangerous.

 

Additional assets (videos, screenshots, logs):

Edited August 7, 2022 by theRedPanda

[Regingrave-]

07.08.2022 в 21:25, theRedPanda сказал:

Velocity dial on the Messerschmitt 410 in the cockpit is displaying a speed lower than it is actually flying unlike all aircraft in the simulator.

It's probably because the gauge is animated incorrectly, will be fixed in the next update.

[354thFG_Panda_]

24 minutes ago, Regingrave said:

It's probably because the gauge is animated incorrectly, will be fixed in the next update.

Thank you))) 

[6./ZG26_Loke]

When one compare this 

 

 

to the guncam recordings posted by @357th_KW, then you will know that the damage effect is way over done. 

[354thFG_Rails]

You know it’s not just hispanukes that can do that right?

[6./ZG26_Loke]

4 minutes ago, 354th_Rails said:

You know it’s not just hispanukes that can do that right?

Properly not in game, but nothing you see in real guncam recordings. As shown above. 

[354thFG_Rails]

I’m just saying that that sort of catastrophic fuel explosion is what HE is doing. Even the German 131’s can do that. Whether it’s realistic or not can be debated but it’s not just a Hispano thing. 

[=RS=EnvyC]

That has nothing to do with Hispanos and everything to do with incorrect HE modelling and fuel explosions.

Edit: lmaaaaaaaaaao fixed

Edited August 21, 2022 by =RS=EnvyC

[RossMarBow]

Fuel explosions now seem to be directly related to how much fuel is left in a tank
 

So planes with multiple tanks explode a lot

And especially planes that have extra tanks that never have fuel in them when flying short 60-30min missions

 

Is the fuel explosion chance now 100%/% fuel remaining = % explosion chance? 

 

 

Edited August 18, 2022 by RossMarBow

[Bulhoes_Neto]

Brief description: 109 and 190  are extremely  resistent 
Detailed description, these planes withstansing 2 or more 37mm shots, and still flying  like nothing else
 

 

Brief description Dying in soft forced landings
Detailed description, most of forced landings pilot are dying

 

Edited August 21, 2022 by Bulhoes_Neto

[Aurora_Stealth]

Brief description: Tempest Mark V flight model appears to be performing at a considerably higher CLmax in-game (estimated CLmax 1.52) than can be substantiated, verified or calculated from primary source materials or test data. Detailed analysis confirms this discrepancy is outside of the 2 - 3% tolerance range.

 

Detailed description, conditions: Analysis of the lift characteristics (CLmax) including aerofoil analysis and primary sources (wind tunnel test data and RAE test reports) give considerably lower CLmax numbers. The Tempest Mark V pilots notes do indeed give surprisingly low stall speeds in clean configuration (85mph) for an aircraft of this weight and size, but it is suspected this is due to instrument, pitot and other errors.

 

Primary sources (as per thread link further below) show CLmax as low as 0.9 - 1.0, one RAE Tempest high speed wind tunnel model describes a CLmax of 1.3 (at 0.75 Mach).

 

Data analysis indicates (thanks to all contributors including @Holtzauge

 

airfoiltools.com 2D Clmax number for the Tempest profile of 1.2

CLmax estimated manual calculation 1.13-1.15 power off
CLmax estimated manual calculation 1.21-1.25 power on

 

The Tempest V was described as being similar to the P-47 D in real life comparisons and reports with regards to turning performance, such as those written by the AFDU (Air Fighting Development Unit).

 

In-game the effect of this discrepancy is leading (under certain conditions) to a lower than expected stall speed (by as much as 15mph or more) and unusually capable manoeuvring characteristics compared to much lighter fighters. This is especially apparent when comparing manoeuvring, G loading in IL-2 with regards to low speed turn performance.

 

Additional assets: Please refer to page 4 of the following thread for primary source materials:

 

Comparative analysis (estimated, clean, power on unless stated otherwise):

 

Bf 109 G                   1.33 (slats out max 1.4)
Fw 190 A                  1.35 - 1.37
Hurricane (NACA)    1.31
Spitfire                     1.36
Hellcat (NACA)        1.4

 

So CLmax of ~1.3 range is typical of non-slatted fighters, which contrasts with 1.52 currently for Tempest Mark V
 

Conclusions:

 

The aerofoil of the Tempest V is of a high speed / low drag type, attempting to achieve laminar flow across a large portion of the wing surface (similar in cross sectional shape and characteristics to the Mustang's aerofoil / wing section).

 

In order to achieve this low drag, and due to its shape... the lift production of the aerofoil is characteristically lower than other conventional aerofoils at low to medium speeds, meeting its CLmax (max lift coefficient) at around 0.75 mach. This means less lift production per sq ft at those lower speeds which would be required to offset the Tempest's heavier weight compared to many of its contemporaries (despite having substantial wing area).

 

This means the true airspeed on the stall is likely to be higher, as well as turning performance being worser in the low to medium speed range, despite the indicated airspeed (IAS) given in the pilot notes... which is likely being affected by pitot tube and instrument errors specific to this design.

 

"With a (clean/power on) Clmax of 1.2, the Tempest at 5,600 kg flaps up stalls around 115 mph, flaps down and (at) an assumed Clmax of 1.6, we get 100 mph, all TAS. 30 mph error on the dial is possible."

"~ 1.21 at mach .17, Re of 4.68e6. At an Re of 4.04e6 mach .2 the maximum Cl for the wing is 1.19"

 

Thanks to@Yak_Panther

for primary sources. 

 

In summary, would recommend correction to the flight model to a (clean/power on) CLmax of 1.2.

Edited September 11, 2022 by Aurora_Stealth

[Roland_HUNter]

Half of the Hurris right wing cant be damaged.
Please check it.

[Roland_HUNter]

Mk-108 hit before wingtip breaks off:
P-47: 3 hit
P-51: 3-4 hit
Spitfire: 2-4 hit
Tempest:3 hit
P-40:4 hit
P-39: 3 hit
P-38: 2 hit
Hurricane LEFT wing: 5 hit
Hurricane RIGHT wing: 6-7 hit
Tempest: 2 hit
Mosquito: 2 hit, and the Mosquito can fly without wingtip:
https://gfycat.com/forcefulfoolhardyanemoneshrimp

Soviet planes: 1-3 hit depending on variants, not tested all of them, because I aimed for the stronger winged planes.

 

[1PL-Husar-1Esk]

FC Camel wings are to weak and shake unrealistic .

1) after one bullet shot wings start to shake as whole plane do

2) next shots and shaking is increased significantly 

3) after 5 shots wing breaks
This damage model is overdone and make Camel too vulnerable and frustrating to fight after taking small damage. In real multiplayer scenario when fire rates are in hundredths bullets per minute this spoils whole game. Guys those bullets should go through canvas. I know you can't simulate it as it should be but how it is now is not good and because of those changes to wings damge model many players do not enjoy the game as they would like. Aafter recent patch and changes to aircraft DM, FC wings are weaker than before. That weak wings plus  some G load make wings fall off in no time.. 

 

 

Same with tail plane when one shot destroys all struts and cables and make plane shake and become hard to fly.

 

Edited September 15, 2022 by 1PL-Husar-1Esk

[1PL-Husar-1Esk]

FC
The fuel tank fires do not accrue. You can shot day long at fuel tank even when it's almost empty, it ain't gonna ignatie and do not explode.  Only engine can burn but that proces lead to nothing  (fire do not propagate even if fuel tanks is close to engine and leaking) wached at 8x accelatated time  with delete plane  after death set to off.

Edited September 17, 2022 by 1PL-Husar-1Esk

[Roland_HUNter]

Please check the damage model of some planes, because some have an indestructible tail section, or in the case of the hurricane, the wing is too strong.

[No_Face]

Brief description: Aircraft engines sometimes seem invulnerable to Sdk.fz 10/5 shoots.
Detailed description, conditions: When I shoot the engines of these planes, the damage appears aesthetically well but does not seem to have any impact. In my tests I only used HE ammunition.
Additional assets (videos, screenshots, logs): Example:

 

I put here the files of the replay in which I shoot different Pe-2 : https://www.swisstransfer.com/d/9347f02d-6fe3-406e-998d-5f32ff4cc951

[[F.Circus]MoerasGrizzly]

Brief description: PO-2 reacts very strongly to ww1 era machineguns

Detailed description, conditions: When under fire from a couple of Albetrosses (Albetri?), this U2-VS plane, in its role as a substitute for the Be2C, jinks extremely strongly when shot down. I can not say if this happened before or after the pilots were shot down, or if the sudden G forces killed the pilots.

 

Assets:

Video of the incident: https://giant.gfycat.com/AssuredShimmeringCaimanlizard.mp4

Track of the incident: Track files

Took place on the Flugpark server.

Edited November 7, 2022 by [F.Circus]MoerasGrizzly

[1PL-Husar-1Esk]

17 hours ago, [F.Circus]MoerasGrizzly said:

Brief description: PO-2 reacts very strongly to ww1 era machineguns

Detailed description, conditions: When under fire from a couple of Albetrosses (Albetri?), this U2-VS plane, in its role as a substitute for the Be2C, jinks extremely strongly when shot down. I can not say if this happened before or after the pilots were shot down, or if the sudden G forces killed the pilots.

 

Assets:

Video of the incident: https://giant.gfycat.com/AssuredShimmeringCaimanlizard.mp4

Track of the incident: Track files

Took place on the Flugpark server.

It looks like fuel tank explosion. Nothing wrong with that except there is no fire....

Edited November 8, 2022 by 1PL-Husar-1Esk

[[F.Circus]MoerasGrizzly]

2 hours ago, 1PL-Husar-1Esk said:

It looks like fuel tank explosion. Nothing wrong with that except there is no fire....

I'm no expert or anything, but it seems like *jolt* on the starboard wing that causes the plane to spin like that, rather then a fuel tank explosion which I'd expect to have a lot more effect around the center of the plane, and a more erratic effect on its flight path.

Edited November 8, 2022 by [F.Circus]MoerasGrizzly

[1PL-Husar-1Esk]

48 minutes ago, [F.Circus]MoerasGrizzly said:

I'm no expert or anything, but it seems like *jolt* on the starboard wing that causes the plane to spin like that, rather then a fuel tank explosion which I'd expect to have a lot more effect around the center of the plane, and a more erratic effect on its flight path.

You might be right, need to test it , take alb and attack some Po2s. In multiplayer environment there is also lag issue, that might be collision. Another is invisible object like a tree, this happened in the past. 

[moustache]

Brief description:

MG interne damage

Detailed description, conditions:

reappearance of an old bug, enemy small caliber machine guns are again able to damage the internals of a tank or injure/kill members inside the tank...

Additional assets (videos, screenshots, logs):

bug MG dommage interne.rar

Your PC config data (OS, drivers, specific software):

no mods, driver ok

[357th_KW]

Brief description: P-38J suffers a loss of control at low speed
This was mentioned in this thread below, but many had never seen it and/or couldn't reproduce it

 

Detailed description, conditions: The P-38J appears to enter some sort of tail stall if you use forward elevator with flaps deployed.  Once that happens, it flips into an inverted dive, and cannot be recovered with the elevator.  It appears that retracting flaps will allow the aircraft to eventually start flying again.  There is no mention of this behavior in the actual P-38 pilots manual, or any warning against using forward elevator with the flaps deployed, so my suspicion is that this behavior is incorrect. 

Additional assets (videos, screenshots, logs):  Track of the tail stall behavior

[Roland_HUNter]

Brief description: Invisible tracers, no hit on the enemy
Detailed description, conditions: You can hear the shots and 1x-2x muzzle flashes, but no tracers or hits. The event happened on the finnish server. After experiencing this, I went to another server without restarting the game, selected exactly the same aircraft type and everything worked fine.
Additional assets (videos, screenshots, logs): Example:/report (http://stats.virtualpilots.fi:8000/en/sortie/3214731/?tour=58)

 

[JG4_Moltke1871]

I have a question for the attackers almost in WW1…. When ever I create a mission in @SYN_Vander’s EMG or fly career in @PatrickAWlson’s campaign generator the AI show’s strange behaviour. It seems the AI flight lead makes a slow flying stall contest. The rest of the AI squad can’t hold formation and crash. A similar behaviour I also had with Stukas. Is there any problem known with the AI in that case?

Attackers show that behaviour are Halberstadt and DFW with AI as flight lead.

Edited December 22, 2022 by JG4_Moltke1871

[SYN_Vander]

17 minutes ago, JG4_Moltke1871 said:

I have a question for the attackers almost in WW1…. When ever I create a mission in @SYN_Vander’s EMG or fly career in @PatrickAWlson’s campaign generator the AI show’s strange behaviour. It seems the AI flight lead makes a slow flying stall contest. The rest of the AI squad can’t hold formation and crash. A similar behaviour I also had with Stukas. Is there any problem known with the AI in that case?

Attackers show that behaviour are Halberstadt and DFW with AI as flight lead.

 

Does this still happen with the latest version? I had hoped it was fixed. I have even tried to lower the speeds for these aircraft. It is definitely something that was introduced in one of the latest updates, because it was never a problem.