Flaps Management

[FLS]

The best flap tip I was given was to let the flaps do the work and not increase drag by adding elevator unless you have to make a desperate shot.

I wouldn't generally agree with that advice. You increase drag by adding lift and also by adding flaps. If you can make the turn with your elevator instead of your flaps you are better off.

Traveler, in a P-38, the first notch is 50% extension in the real world and 8 degrees of deflection.  After the first notch the deflection really goes up with each notch of extension since the lower rail hits a stop.  In AH the first notch represents the 50% extension and 8 degrees of deflection which is spoke of as the Maneuver flaps.

I don't think that's correct. The 3rd position is more likely for 50%.  That's also indicated by the turn performance.

[Traveler]

You guys are missing the point. It's not relevant whether a particular aircraft has a 50% flap setting. The point is before 50% gives you most of the increase in lift coefficient, after 50% gives you the most increase in drag. This is a useful guide for new pilots.

You also should not assume the 4 or 5 flap settings are equally dividing the extension range.

The decision to model flaps with discrete settings is a game design choice. I believe aircraft with variable flap settings generally had markings for flap positions HTC models.

From the indicator in the cockpit in AH the gauges showing the flap extension appears to be even distribution for each increment of flap up or down, no matter what aircraft.

[Mar]

From the indicator in the cockpit in AH the gauges showing the flap extension appears to be even distribution for each increment of flap up or down, no matter what aircraft.

You don't fly 190s much do you?

[Traveler]

You don't fly 190s much do you?

seldom , maybe once a year.

[Oldman731]

The best flap tip I was given was to let the flaps do the work and not increase drag by adding elevator unless you have to make a desperate shot.

Agreed, for certain planes.  Corsair and 38G, in my experience, benefit most from this technique, the 109s don't.

- oldman

[FLS]

From the indicator in the cockpit in AH the gauges showing the flap extension appears to be even distribution for each increment of flap up or down, no matter what aircraft.

The deflection angles the indicator shows and what the graphic model shows and what the flight model uses don't have to agree. They may be exactly the same in some cases but it seems unlikely.

[FLS]

Agreed, for certain planes.  Corsair and 38G, in my experience, benefit most from this technique, the 109s don't.

- oldman

Good point. With the 38 you increase the wing area. That's probably what Randy was referring to.   

[Traveler]

The deflection angles the indicator shows and what the graphic model shows and what the flight model uses don't have to agree. They may be exactly the same in some cases but it seems unlikely.

how do you know this?  has AH published this information somewhere?

[FLS]

how do you know this?  has AH published this information somewhere?

I believe it's been mentioned but I don't have a reference handy.

[Traveler]

I believe it's been mentioned but I don't have a reference handy.

Mentioned by Hightech Creations? or just mentioned by other players?  Would be nice to know the official version.

[Mar]

The flap indicators have never shown the angle the flaps are at, just which of the five/three/whatever positions they are in at a glance.

190 (including 152) flaps have 3 notches, the third one travels as far as both the top two combined and the indicator shows this as well. I'm not sure if any other planes have a notch that travels more or less than the others, but this shows that the indicator shows where the flaps are at from full up through full down.

[Randy1]

how do you know this?  has AH published this information somewhere?

The confusion comes when extension and deflection become interchangeable.  The P-38 is a Fowler flap hybrid.  The flap drops just enough to clear the trailing edge then slides back until the full flap is out of the pocket and extended behind the trailing edge fully.  In doing that it goes to 8 degrees deflection.  This gives the most efficient flap setting. From this point on any further extension of the flap stops since the bottom guide rail hits a stop. The top rail is still open.  That means the bottom of the flap is held firm while the top edge of the flap is being pushed back greatly increasing the deflection angle without any further extension of the flap from the trailing edge of the wing..  

In an old post HTC noted the first notch in AH P-38 was modeled to that 8 degrees which is about 50% of the top rail travel and 100% of the bottom rail travel in a real P-38. Another old post noted not to consider each notch to be equal since planes had different flap styles.

Keep in mind a flap on a plane like a door hinge to the trailing edge or split flaps offers no extension to the wing cord but Fowler flaps do add to the wing cord.  I am guessing here but I think the word "extension got tied to flaps with the invent of fowler like flaps.

Best I can tell HTC did a super job of modeling our AH flaps making them as close to real world as practical.

[colmbo]

The other thing you need to know about flaps is that the first 50% extension gives you most of the increase in coefficient of lift, the second 50% gives you most of the increase in drag. When you do need flaps don't use more than you need.

Real world never heard this expressed as a percentage.  I've always heard up to about 20 degrees is good, beyond that is just more drag.  

[FLS]

Real world never heard this expressed as a percentage.  I've always heard up to about 20 degrees is good, beyond that is just more drag.  

If you have 40 degrees full extension that would fit.     It's meant to be a general point for understanding flaps effect on lift and drag.  

Real world reference for this expression is Aerodynamics for Naval Aviators pg 45.

[Owlblink]

Link to full post

Thank you Randy1 for this imensely helpful post! Most of us forget or miss the fact that some planes have the fowler (spelling?) flaps which  have an impact on the wings cord!

On most planes, from my experience, anything beyond the first two settings are useful for trying to slow your plane down or to help create lift at slower speeds but does not in fact dicrease your turn radious or increase your turn rate. I remember a conversation sometime back where corshair pilots were testing this out with their flap settings and decided thT anything over two notches is detramental for trying to get better turn performance at a fixed speed but is more usefull for its braking power, snapping the nose back under the horizon when  near an inverted and slow attitude, and holding onto a little bit of lift when in a stall fight (but not to be kept out the whole time).

Does this make sense to you guys?