Flap testing

[=X51=VC_]

I'll start with an apology because I know this has been discussed before but I'm fairly new here and thread searching hasn't given me a conclusive answer.

 

Basically, people are saying since at least a year ago that flap damage is now modeled. But I often see people in multiplayer (don't want to point fingers but it's nearly always Yak-1s) with flaps deployed in combat. So I decided to mess around. Not hugely thorough, but basic test in a few planes I care about, start at 3k and see what happens. Results:

 

Bf109G-2: 15 degrees of flaps (roughly, based on the wing indicator), no issue diving to 700km/h and pulling out hard. If anything it reduced the control stiffening and improved high speed agility

 

La-5: 20 degrees of flaps, no damage at 650km/h, started getting warnings about the structure and didn't go faster anyway as the ground was close

 

Yak-1: somewhere after 500km/h I got "flap rods jammed" and couldn't retract the flaps, but pushed on to 600km/h and no damage or flap rip

 

So it seems fighters that have a combat flap setting can use it basically without structural consequence at any speed, and the one that has only "up" or "down" positions can still use what is basically landing flaps at most combat speeds.

 

As I said, I apologise for bringing this up again but to me that doesn't seem right.

Edited January 20, 2018 by VC_

[-=PHX=-SuperEtendard]

In the case of the Yak the airflow pushes them up at high speeds, I think over 300-350 km/h they are rather retracted. If the rods get broken I dont know if they would get locked in that near retracted position or if they would come down as speed decreases and stay locked in that position.

[=X51=VC_]

In the case of the Yak the airflow pushes them up at high speeds, I think over 300-350 km/h they are rather retracted. If the rods get broken I dont know if they would get locked in that near retracted position or if they would come down as speed decreases and stay locked in that position.

 

They come back down (I pulled up and bailed out to check where they were).

[216th_Jordan]

They come back down (I pulled up and bailed out to check where they were).

 

It sounds like you didn't use ingame recording and no outside views? Flaps are very tough, I'd think non-pneumatic ones should break/get stuck easily but I don't know how realistic or not that is. I mean your ailerons also don't fly away when you roll hard...

Real life data is probably hard to come by with things like these.

Edited January 20, 2018 by 216th_Jordan

[Y-29.Silky]

Oh God not the "yak rainbow flap" circle jerk again. 

I think it's the automatic flap function because the 190 can snap fast with flaps deployed as well (90% of 190 pilots don't know that because they're too busy running away). 

[=X51=VC_]

It sounds like you didn't use ingame recording and no outside views? Flaps are very tough, I'd think non-pneumatic ones should break/get stuck easily but I don't know how realistic or not that is. I mean your ailerons also don't fly away when you roll hard...

Real life data is probably hard to come by with things like these.

 

As I said, I wasn't running a scientific experiment just a quick test. If flaps are that strong I have no issue, I just wanted to double-check because the chat was telling me to "retract flaps" from basically 300km/h and I always assumed they had structural limits different to the other control surfaces as they were mainly intended for low speed use.

 

Oh God not the "yak rainbow flap" circle jerk again. 

 

I think it's the automatic flap function because the 190 can snap fast with flaps deployed as well (90% of 190 pilots don't know that because they're too busy running away). 

 

Not circle jerking about the Yak, just observing it's the main one I see flap use on in MP. If anything the La-5 and 109G-2 got just as much benefit from 20/15 degrees. I flew a bit in Berloga with a 109 flaps to 15 degrees the whole time and how it turned surprised me, I'll probably use them a lot more now!

[=EXPEND=Tripwire]

I'll probably use them a lot more now!

No, don't lower your standards. There is hardly anything realistic about simulating air combat in a 109 or Yak deploying flaps like we see in-game. Some flap use, sure (especially planes with designated combat flaps), but it is incredibly rare to fight a Russian plane that is not abusing flap use. Yaks, Lagg3s, even LA5s..

 

We have artificial engine timers to prevent unrealistic use of WEP. Be amusing to see flap usage get the same treatment.

 

I remember one thread where someone asked a current yak3 pilot about deploying flaps at well above landing speeds. IIRC the reply was something like he would hope to hell both flaps would rip off evenly.

[Dakpilot]

No, don't lower your standards. There is hardly anything realistic about simulating air combat in a 109 or Yak deploying flaps like we see in-game. Some flap use, sure (especially planes with designated combat flaps), but it is incredibly rare to fight a Russian plane that is not abusing flap use. Yaks, Lagg3s, even LA5s..

 

We have artificial engine timers to prevent unrealistic use of WEP. Be amusing to see flap usage get the same treatment.

 

I remember one thread where someone asked a current yak3 pilot about deploying flaps at well above landing speeds. IIRC the reply was something like he would hope to hell both flaps would rip off evenly.

 

 

Please don't go down this road again 

 

even in the Yak 1 manual it allows you to fly at speed until the flap are pushed fully in by air pressure after take off and then lock them up

 

WWII Yak pilots talk of using Flaps to make tighter turns when dealing with bombers but would not use against fighters because of speed loss from drag, their most important principle was to keep up combat speed when in presence of German fighters

 

people do abuse use of flaps in general because most fights in game are flown in a very different way to real history

 

There is a drag penalty to using Yak flaps, but above 300kmh or so they are not deployed (pushed in) so no drag

 

people definitely  "game" the flaps but the "flaps should rip off business" is not accurate, if you deploy above landing speed they just don't come out, until slow enough (what would rip off?)

 

Cheers, Dakpilot

[=X51=VC_]

If they're fully pushed in by airflow and that was normal operation why did my flap rods break and I wasn't able to lock them up or retract them after I slowed down?

 

Anyway, I always though split flaps like Yak, LaGG and Spitfire have were meant mainly for large increase in lift and drag at low speeds (mainly to aid landing) but plain hinged flaps like the 109 are designed to improve lift without a huge drag penalty at low deployment angles. Was using 10-15 degrees of flaps setting for combat normal for 109 pilots historically? Or is this a myth created by modern sims?

[Dakpilot]

There are many Luftwaffe pilot reports using 'combat' flap on 109 for increased turn in 'awkward' moments, so it did happen, hard to say how much

 

Perhaps rod breaking on Yak has been introduced as an attempt to stop people gaming the flaps at historically unused speeds? I have not experienced this (there were  changes to flaps a while ago with a patch)

 

In reality I would expect pilots to have been generally cautious with abusing the pneumatic flaps, having relief valve blowing off while trying to force them out would seen counter intuitive, and any damage to flaps system can be life threatening on landing or asymmetric deployment a possibility (very unpleasant) 

 

Cheers, Dakpilot

[=EXPEND=Tripwire]

Please don't go down this road again

 

even in the Yak 1 manual it allows you to fly at speed until the flap are pushed fully in by air pressure after take off and then lock them up

IIRC you had to select a neutral position to have them blow back up (releasing pressure). Not fight against the pneumatic system trying to keep them deployed.

[Dakpilot]

Yes, it is a real shame that stage/setting is not modelled, we only have up and down modes in BoS, but I guess it does not really change the functionality

 

still it would be great to have, along with many other 'simplifications' but I guess a line has to be drawn somewhere or costs will go up

 

Cheers Dakpilot

[=EXPEND=Tripwire]

A quote from Bert_forster

 

 

"Now with respect to YAK Flap design. I have a close friend who maintains (runs an aircraft restoration/maintenance company) various warbirds and also flys multiple types. One aircraft in his charge (and he flies) is one of the new YAK3 re builds powered by the Allison engine. I posed the following question to him:

 

 

 

" C....... a curly one for you Is there any Flap load relief system in the Yak 3 ? By that I mean what happens if you select Full flap then accelerate the aeroplane ? Will the Flap progressively blow black as the Air load increases ? Or if say you are running at high speed and bang the flaps out what happens? Do they just deploy a little or attempt to go full throw and something gets bent ?"

 

 

 

His response:

 

 

 

"Nothing like that on the yak 3 deployed at high speed I'm sure they would remove them selves and hopefully both at the same time"

[Dakpilot]

I guess the WWII Yak-1 manual is wrong

 

that is the only possible explanation

 

this has previously been debated to the nth degree with pictures of valves relief valves and pressure graphs....etc.etc.

 

I'm out 

 

Cheers, Dakpilot

[4thFG_Cap_D_Gentile]

(there were changes to flaps a while ago with a patch)

 

The devs said in an update alright and everything went quit about Yak flaps afterwards LOL 

 

https://forum.il2sturmovik.com/topic/32379-yak-vs-109/

Edited January 21, 2018 by Ojisan_Mjoelner

[162nd-YU-Markoni]

Well i know a man who was a Yak-9P pilot. So i can ask him what you guys want to know.

He was not ww2 pilot but was a military pilot after ww2 and he flew on Yak-9P.

[=EXPEND=Tripwire]

I guess the WWII Yak-1 manual is wrong

 

that is the only possible explanation

 

Where in the manual does it state that the flaps blow back when set to the down position? Sure when set to Neutral, because the pressure has been released.

 

The whole blowback even when under pressure was someone on the Russian forums interpretation of how they work. And they managed to convince the developers of this too.

 

Anyway like you have said, this has been done to death.

 

Still looks ridiculous fighting planes with their flaps out all the time. The Yak is only one of many planes in this sim with flaps out, so targeting one plane as the problem is wrong.

[303_Kwiatek]

Another important thing is that deployed flaps got much lower G tolerance.  Example if plane got about 4-5 G allowed, with flaps down it got about 2.5 g max. 

[Herne]

Another important thing is that deployed flaps got much lower G tolerance.  Example if plane got about 4-5 G allowed, with flaps down it got about 2.5 g max. 

 

care to explain why ?

[=EXPEND=Tripwire]

 

8. New flaps functionality:

8.1 Flaps pneumatic valve can be set to the neutral position instead of retracting position, making the flaps retract by air flow pressure instead of a sharp retracement.

8.2 An incorrect flaps behavior, while pushed back by the air flow pressure, has been addressed.

 

 

Wow!

 

This might be the end of the flaps blow-back when in the down position!

[CisTer-dB-]

care to explain why ?

 An aircraft with the flaps, slats, gear down or anything else out loose some of it's for the structural integrity,  

[Herne]

 An aircraft with the flaps, slats, gear down or anything else out loose some of it's for the structural integrity,  

 

well I can understand how it might be a problem form the perspective of speed, but not so much from the perspective of pulling a hard turn. Indeed flaps in a combat setting should allow you to pull as much G's at an even slower airspeed giving you a tighter turn.

[-SF-Disarray]

care to explain why ?

 

At a guess it would be the force loading at angles the plane isn't strong in. With landing gear for example, a new torsion force is applied at the connection point. I'd imagine the same is true for flaps, though less extreme.

[CisTer-dB-]

It's just the way it is Herne, a wing with the flap in are part of the wing structure and it reinforce the the wing itself, on the other hand when the flaps are out they aren't. For a lack of better words