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Spitfire and Flap deployment...


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Ok,

 

I have now convinced myself that in order to agree / be coherent with it's present implementation of stick forces even for non FF joysticks, 1C / 777 should add the pitching down moment to the Spitfire Vb when flaps are deployed, and this should actually correspond to a slight displacement of the stick inside the cockpit, that the pilot would need to counter by pulling.

 

Why ? Because the trim tabs already do that on all control surfaces of aircraft with trim tabs, either pilot controlable or ground set. We can easily notice it even on ground when we give power and the propwash is enough to act on the tabs and make the elevator change position, with the corresponding displacemnet of the stick, even if very slight, being visually represented in the cockpit too.

 

Same applies for aileron and rudder tabs and their associated control surfaces and cockpit controls, that displace as "q" increases...

 

So, the problem of simulating the effect this way is already there, and means that full travel will not be possible in one of the directions, but I think the end result should be more intuitive to the virtual pilots. Even better if it can be reproduced for force feedback controllers...

Edited by jcomm
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Ok,

....

So, the problem of simulating the effect this way is already there, and means that full travel will not be possible in one of the directions, but I think the end result should be more intuitive to the virtual pilots. Even better if it can be reproduced for force feedback controllers...

You don't have to force the stick far off center. Trim forces induced by the flaps deployment are typically way less than stick forces induced by high speed or wrong trim. Of you force the stick just 5% of the whole travel off center, it willl be very noticeable on any Warthog type of gimbal. The You then just compress the whole travel range in the 95% remaining travel.

 

It is old stuff, any several sims do this. It is one of the design choices that uses something unrealistic to simulate something realistic on an unrealistic setting. ;)

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Indeed Zach,

 

and at least in IL-2 I can see the effect of all trim tabs coming into play as airflow increases over them, and the controls returning to their neutral when speed decreases considerably. This is probably the only fight sim where I can see this happening. Even in the 109s and 190s, where there is still a ground adjustable trim tab, we can see , using a close view,  the elevator moving a bit as propwash increases over the tail when we add power on ground - and that pretty much explains why the reaction of the elevator is different from what we sense in another sim.... and IMHO is wrongly modelled there or assuming a 0º displacement of the ground adjustable elevator trim tab...

 

P.S.: And, indeed, there is after all a slight initial pitching down, as flaps are deployed, specially noticeable at higher speeds. I've been looking more carefully from outside ( F2 ) view.

Edited by jcomm
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  • 2 weeks later...

 

P.S.: And, indeed, there is after all a slight initial pitching down, as flaps are deployed, specially noticeable at higher speeds..

 

 .."as flaps are deployed, specially noticeable at higher speeds "" ??? ...what 're you talking about? :o: 

 In real life, you cannot deploy the landing flaps at "hight speed" in neither aircrafts. ..Specially in a Spitfire? ..at hight speed NEVER! .. because if you could deploy the flaps, they will be ripped, and the wing would being seriously damaged..

..this is probably the worst bug of this game. 
Edited by III/JG52_Otto_-I-
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I thought I read somewhere that the flaps had a pneumatic system, and could not fully deploy if there was too much resistance due to air pressure. 

 

This makes them incredibly useful in combat

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Just like in the Yak the pneumatic flaps of the Spitfire were fitted with escape valves which prevented the system from overloading at high speed. That results in decreasing flap deflection the higher the speed. That is accurately represented ingame.

 

What really is missing in the sim is flap damage by Gs inform of hinge collapse and mechanical lockdown of the rods due to overstress.

Edited by 6./ZG26_5tuka
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This makes them incredibly useful in combat

It makes them incredibly useful in game. In combat, no pilot would abuse the flaps to the degree we see it in game, and no flaps would take this amount of abuse.

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It makes them incredibly useful in game. In combat, no pilot would abuse the flaps to the degree we see it in game, and no flaps would take this amount of abuse.

 

well those escape valves that ZG26_5tuka described would prevent such aircraft from being over stressed.

 

I did a quick search for combat flaps :-

 

CkvrPKs.png

 

This is from https://books.google.co.uk/books?id=P0KiPMJuXkUC&pg=PA65&lpg=PA65&dq=combat+flaps+in+ww2&source=bl&ots=bSXPWpZ9Xo&sig=6YW2qiHJ9xX9eRS2rcV7ftQllv8&hl=en&sa=X&ved=0ahUKEwi-poLQzO_VAhXQEVAKHVO3Cyg4ChDoAQgnMAA#v=onepage&q=combat%20flaps%20in%20ww2&f=false

 

Now I know we don't have a P38 in game, I'm just trying to point out that flaps are a perfectly valid tool to be used in combat, although I would like them to be subject to what was possible in the real world. If a 109 for example could drop full flaps in a 600 km/h dive in the real world, then that should be in game, allthough I suspect very much that they might break off, before they fully deployed at those speeds.

 

The real problem's we have though is that we just don't really know what the limitations were. What is modeled may not be entirely accurate, but I think its just too much to ask that they could ever be entirely accurate.

Edited by =11=herne
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See in this way: Spitfire don't use "maneuver flaps", but "landing flaps".  :)

 

You find combat report of P-51 pilots using - some degrees - of flaps during combats, with variable results.

Edited by Sokol1
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Sure flaps could be used in combat but in most cases anything above manouvering (~10°) would be irrational or dangerous.

 

As for the Bf109 the flaps were only designed for the stress during landing (hence why above 250km/h flaps must not be fully deployed). The manual handle however acts as a protection mechanism since the high resistence at high speed would prevent the pilot from overstressing the mechanism mistakenly

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Just like in the Yak the pneumatic flaps of the Spitfire were fitted with escape valves which prevented the system from overloading at high speed. That results in decreasing flap deflection the higher the speed. That is accurately represented ingame.

 

 

A "escape valve" will not compromise the compressed air storage?

 

"Spitfire...As mentioned, the flaps are also operated off the air pressure system, and they are held in the open position against aerodynamic load by air pressure.

So, if you lose air pressure because of a leak in the flap system, the stored air pressure in the compressed air tanks will rapidly leak, and can easily exceed the small engine driven air compressor’s ability to restore the pressure. In this situation, you will eventually have the flaps blow back, and you will also have no air pressure to operate the brakes on landing. "

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There shouldn't be a displacement of stick due to flaps being deployed, you'll need a bit of back pressure to counter it but that is what trim is for. And the Spitfire flaps are just for landing.

 

I agree regarding it's use, but as far as the back pressure goes, what would happen if the pilot didn't apply it ? Would the stick stay put ?

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well those escape valves that ZG26_5tuka described would prevent such aircraft from being over stressed...

 

..Now I know we don't have a P38 in game, I'm just trying to point out that flaps are a perfectly valid tool to be used in combat,

You have no idea, ...P-38 have Fowler flaps, and Spitfire have Split flaps, with only landing position, ..BTW the Bf-109 had slotted flaps,

They are different systems and Split flaps is the worst system of them for combat manoeuvring.

 

 flaps1.GIF

 

 

 

A "escape valve" will not compromise the compressed air storage?

 

"Spitfire...As mentioned, the flaps are also operated off the air pressure system, and they are held in the open position against aerodynamic load by air pressure.

So, if you lose air pressure because of a leak in the flap system, the stored air pressure in the compressed air tanks will rapidly leak, and can easily exceed the small engine driven air compressor’s ability to restore the pressure. In this situation, you will eventually have the flaps blow back, and you will also have no air pressure to operate the brakes on landing. "

 Yes, you are right; ..And when the escape valves open, it produces flap fluttering and aircraft vibration and some instability, that is not modelled in the game at present date.. 

 

And... Otto, higher speeds withing the flaps deployment range ( bellow 140 mph indicated )...

I think that 140mph (≈180 km/h) is not high speed in any case.,

Edited by III/JG52_Otto_-I-
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