Flap Type and Efficiency

[thorsim]

Same thing comes up with the Corsairs. "Dump speed and get the flaps out immediately!" (personally, I think the rudder is just as if not MORE important).

i feel the same way about the rons ...

but i fly the a8 so dumping speed happens when you think about turning  ...

 

[Karnak]

90% of the so-called elite will go on giving tips and hints on how to out-turn anything with flaps in this game, including on this sub-forum. Most of the discussions helping new pilots involve "Use this plane's flaps, they're fowlers, and will make you turn super tight!"

I am not really one of the elite, but I have never recommended a new player use flaps.  I always point them towards fundamentals first.  They can learn about flaps on their own, once they have some idea how to fight.

[Captain Virgil Hilts]

Nice attempt at flamebaiting, Hilts, but you fail.

No attempt at flame baiting. Not at all. Merely a statement of fact well proven by your posting history.

[Boozeman]

Well, I asked this question in some P-38 thread not long ago, but no replies. Hopefully on this more focused thread, i`ll be luckier.

Raptor's diagram attributes a distinct "nose down pitch" to pretty much all the flap types when deployed.
In AH, all flap types generate a distinct "nose up pitch" when deployed.

So, which is right?
       

[FLS]

Well, I asked this question in some P-38 thread not long ago, but no replies. Hopefully on this more focused thread, i`ll be luckier.

Raptor's diagram attributes a distinct "nose down pitch" to pretty much all the flap types when deployed.
In AH, all flap types generate a distinct "nose up pitch" when deployed.

So, which is right?
       

It depends on the aircraft design. Some go up, some go down.

[BnZs]

Probably because in this game they're modeled as anti-gravity repulsor lifts.

Krusty, going by Dokgonzo's listed turn radii, I once got these figures:

A. Full deflection of the P-38's Fowler flaps reduces turn radius, as compared to non-flap radius, by about 26%.

B. Full deflection of the P-47D-40s's slotted flaps reduces turn radius by 25%.

C. Full deflection of the of the Fw-190s *split* flaps reduce turn radius by 24%.

D. Full deflection of the P-51D's plain maneuvering flaps reduce turn radius by 19%

E. Full deflection of the F4U-1D's flaps reduce turn radii by by 40%.

B, C, D, and E all seem a whole lot more worthy of questioning comment than A, IMO. As you can see, the the P-38s flaps cannot be superflaps, since they do not reduce the turn radius by degree remarkable in comparison to other aircraft. That the P-51D's plain flap comes out worse than the 190s split flap and that these flaps are right up there with some inherently better maneuvering flaps also seems odds.

[Anaxogoras]

E. Full deflection of the F4U-1D's flaps reduce turn radii by by 40%.

That is a lot.  It's no wonder good F4U pilots give me fits if I'm not in something with good powerloading.

[Boozeman]

It depends on the aircraft design. Some go up, some go down.

In AH, all go up. Regarding the AC design, can you give a little more detail? Thanks!

[Saxman]

Krusty, going by Dokgonzo's listed turn radii, I once got these figures:

A. Full deflection of the P-38's Fowler flaps reduces turn radius, as compared to non-flap radius, by about 26%.

B. Full deflection of the P-47D-40s's slotted flaps reduces turn radius by 25%.

C. Full deflection of the of the Fw-190s *split* flaps reduce turn radius by 24%.

D. Full deflection of the P-51D's plain maneuvering flaps reduce turn radius by 19%

E. Full deflection of the F4U-1D's flaps reduce turn radii by by 40%.

B, C, D, and E all seem a whole lot more worthy of questioning comment than A, IMO. As you can see, the the P-38s flaps cannot be superflaps, since they do not reduce the turn radius by degree remarkable in comparison to other aircraft. That the P-51D's plain flap comes out worse than the 190s split flap and that these flaps are right up there with some inherently better maneuvering flaps also seems odds.

Keep in mind that per its own operator's manual the F4U already gets a SIGNIFICANT reduction in stall speed at power-on and full flaps as opposed to power-on clean. It's been a while since I've looked at it but it may have been as high as 40% stall speed reduction, so these flaps are generating a TON of additional lift. Which also only makes sense for a carrier aircraft that needs to make abnormally slow landing approaches. I want to think that the P-51's stall speed reduction is in line with this as well, about 19% speed reduction at full flaps power-on, so HTC may have it modeled that % turn radius reduction is roughly equivalent to the % stall speed reduction.

Now SHOULD it be like this? That I don't know enough physics to answer, but it sounds ludicrous to me that that much additional lift wouldn't have a significant effect on turn radius.

[Anaxogoras]

The smallest possible radius is equivalent to turn-rate at stall speed.  If you can keep the same turn-rate but fly slower, your radius will decrease.  In the F4U, dropping flaps not only reduces the stall speed, but even increases the turn-rate.  So, yes, the flaps are clearly increasing the lift.  For the rest of our aircraft, there is usually a turn-rate penalty that comes with the smallest possible radius vs. the no flap radius.

[FLS]

In AH, all go up. Regarding the AC design, can you give a little more detail? Thanks!

In general the movement of the lift and drag forces when you add flaps and any change in airflow over the tail determines the direction of the pitch moment. In a particular aircraft the amount of flaps added can change the direction also.

I don't know that the pitch moment from flaps is modeled Aces High. Adding flaps will have the effect of increasing the wing incidence so you'll have more lift for the same pitch attitude. You may just be seeing the increased lift.

[bozon]

The smallest possible radius is equivalent to turn-rate at stall speed. 

If stall speed is defined as the slowed speed one can fly without loosing altitude, than it is impossible to turn at that speed without loosing alt.

It is meaningless to compare "full flaps" state between planes as full means different things on different planes, even on planes that had the same type of flaps. Flaps produce both lift and drag. The drag is needed for landings but is bad for sustained turning. The so called "maneuvering" setting is supposed to strike a balance between the added lift, drag and the available power of the plane and as far as I know is never the "full" setting, intended for landing.

[Anaxogoras]

Good point, "at stall speed" isn't very precise.  It would be an airspeed a little bit faster than stall speed, and even that's not precise.

[Stoney]

In the F4U, dropping flaps not only reduces the stall speed, but even increases the turn-rate. 

Don't forget Hammer's graphic.  The F4U only increases turn rate up to the third increment of flaps.  Any more than that and turn rate decreases.

[Kweassa]

Don't forget Hammer's graphic.  The F4U only increases turn rate up to the third increment of flaps.  Any more than that and turn rate decreases.

However, often there are situations where a significantly smaller turn radius in the short term, may actually provide the most important critical advantage over maintaing a better turn rate in the long run. Having a better turn rate doesn't amount up to much when the plane behind you gains a smaller turn radius just long enough to blow you out of the sky.

- just a reminder, ofcourse.