Flaps usage in real combat

[icepac]

I think they should simply snap off or get stuck if actuated at too high a speed except for planes in which they use spring tension to limit their actuation into a position that would snap them off.

[asterix]

Flaps allow more lift at slower speeds but with a substantial penalty of drag and do not allow higher angle of attack.

Slats allow more lift at slower speeds by allowing more angle of attack to be utilized.

My argument is that the flaps in aces high are allowing more angle of attack instead of simply increasing lift and lowering stall speed while the slats don't offer any more useful angle of attack than the flaps do yet they also add greatly to the drag even at zero angle of attack.

In real life, you don't pull  more angle of attack when using flaps but rather use the additional lift to get around more quickly when in a high G banked turn at the same angle of attack.

I don`t know if icepack is right or wrong but how do you see what gives you what angle of attack in Aces High. You can`t see the airflow direction, can you? Also slats may allow more angle of attack but only on the part of the wing these are fitted. The rest of the wing could be stalling and creating a lot of drag. Planes also have different weight, power etc, so it is pretty difficult to make accurate assumptipns imho.

[FLS]

Yeah but it surely helps as does having walked up to and seen the actuation of flaps on many warbirds in person and discussing it with guys like howard wolko as you are watching the surfaces actuate.

Me and Nels Wolko, his son, used to get lectures from howard on how the various control surfaces worked on the RC airplanes we built in his workshop.

Flaps allow more lift at slower speeds but with a substantial penalty of drag and do not allow higher angle of attack.

Slats allow more lift at slower speeds by allowing more angle of attack to be utilized.

My argument is that the flaps in aces high are allowing more angle of attack instead of simply increasing lift and lowering stall speed while the slats don't offer any more useful angle of attack than the flaps do yet they also add greatly to the drag even at zero angle of attack.

In real life, you don't pull  more angle of attack when using flaps but rather use the additional lift to get around more quickly when in a high G banked turn at the same angle of attack.

My point is that I know how they work, have discussed it with people who regularly fly planes with slats and flaps, and have flown a pretty good variety of planes myself.....thought most of them did not have slats.

I just think a few things could use a little adjustment for the sake of reality but HTC has to walk a fine line between full realism and having a sim where the extreme realism brings on enough difficulty that people decide they don't enjoy flying it.

This is why you don't see spins as easily entered by pulling hard Gs with controls crossed as you did in warbirds before version 3.

A sim is no good if nobody want's fl fly it.

I don't have the exact numbers but neither does anybody else on this thread.

The experienced may not need the exact numbers because experience here and in the real world would indicate flaps and slats don't quite act as they should..........close, but some inaccuracies that could be closer.

I think you're a little confused about flaps.  Flaps change the effective incidence of the wing so if you maintain pitch attitude the increased lift actually comes from increased AOA as well as increased co-efficient of lift. Flaps also allow a higher AOA because they change the shape of the wing.

[FLS]

I don`t know if icepack is right or wrong but how do you see what gives you what angle of attack in Aces High. You can`t see the airflow direction, can you? Also slats may allow more angle of attack but only on the part of the wing these are fitted. The rest of the wing could be stalling and creating a lot of drag. Planes also have different weight, power etc, so it is pretty difficult to make accurate assumptipns imho.

The flapped portion of the wing is at a higher AOA then the rest of the wing so it's the first to stall. That's why your ailerons are more effective in the stall with flaps down. You can see AOA with smoke on and in films with trails on. The smoke or trails show you the attitude in relation to the relative wind. Here's an example. You see the tail move above and below the smoke as the AOA changes.

http://www.youtube.com/watch?v=YuTycIGXfno

[icepac]

Flaps change the angle of incidence of a wing.........not the usable angle of attack of the airplane.

[colmbo]

Flaps change the angle of incidence of a wing.........not the usable angle of attack of the airplane.

Angle of incidence is fixed....like with bolts and stuff and can not be changed.  An exception being the F8U Crusader.

[asterix]

I would not say that the flaps change the incidence of a wing. First of all the incidence is measured at a point where the wing meets the fuselage. On some aircraft (P-51 for example) the flaps are mounted away from the point where incidence is measured, so these do not change it. Secondly if angle of incidence is measured between a chord line and reference axis then spilt flaps for example should not change the chord line. The upper trailing edge is further away from the drooped trailing edge.

What is "effective incidence" and where is it measured?

I would not say that the flapped portion of a wing is always at a higher AOA because the chord line doesn`t seem to change with split flaps.

Does the smoke trail really show the attitude in relation to the relative wind? AOA is usually measured relative to the airflow in front of the aircraft, shouldn`t attitude as well? Does the wing downwash affect the smoke trailing the aircraft in AH2 as it could in real life?

[Brent Haliday]

I think they should simply snap off or get stuck if actuated at too high a speed except for planes in which they use spring tension to limit their actuation into a position that would snap them off.

I Would like to see documentation of that being an actual recorded normal consequence of above speed warning speed flap deployment.

[FLS]

I would not say that the flaps change the incidence of a wing. First of all the incidence is measured at a point where the wing meets the fuselage. On some aircraft (P-51 for example) the flaps are mounted away from the point where incidence is measured, so these do not change it. Secondly if angle of incidence is measured between a chord line and reference axis then spilt flaps for example should not change the chord line. The upper trailing edge is further away from the drooped trailing edge.

What is "effective incidence" and where is it measured?

I would not say that the flapped portion of a wing is always at a higher AOA because the chord line doesn`t seem to change with split flaps.

Does the smoke trail really show the attitude in relation to the relative wind? AOA is usually measured relative to the airflow in front of the aircraft, shouldn`t attitude as well? Does the wing downwash affect the smoke trailing the aircraft in AH2 as it could in real life?

Compare the attitude for the 0 lift AOA with and without flaps. The difference in attitude is the change in effective incidence.

[Brent Haliday]

MA is a lot of fighting on the deck at low speed.  In that environment, using lots of flaps is a good tool.  Scenario fighting is much less of that and a lot more higher alt and higher speed fighting, usually also many on many.  The style of fighting then is different and tends to be more historical in nature.

As for flap restrictions, they are very likely based on documentation for that aircraft (such as pilot's manual or flight-test data).  Some planes could deploy flaps at much higher speeds than others.  Ones you are reading about are P-51's and P-38's, which could deploy flaps at high speed.  Some 109's would have had a very hard time deploying flaps in combat because it took lots of turns on a wheel to get a little bit of flaps out -- it would take forever to get them out and back in again.  (I'm not sure if Marseille used flaps in combat -- could be wrong, but don't remember reading that he did.)  Nevertheless, there are 109's in the game that use flaps all the time once they are scrambling around on the deck.

Complaining about some planes having better flaps or flaps that are deployable at higher speeds is like complaining that the Zero is slower than F4U's, and because of an account here or there (like Boyington being shot down from behind by a Zero), all planes should be given about the same top speed.

The determination that a structure that is deemed safe  at x speed and y deflection is some how not safe at any higher speeds at 1/2 to 1/45 y deflection can not be reconciled with real world physics.  As far as documentation goes it would be silly for the poh to offer more than a max deployment warning for landing on the 109 because it had no other fixed settings.  Should they post numbers for every degree of deployment?   Also I fail to see how a procedure that is simple enough to use at low speeds and altitudes somehow becomes more complicated with altitude and speed.

Restricting the FDS by POH (while ignoring the basic physics involved) in an air combat simulation is like a rally racing game limited to the car's operators manual.  It may be easy to justify, right up to the point where you see the actual real world operation of a rally car by a rally car driver in a race extracting the maximum possibilities from his vehicle.
Once you see the truth the video game would leave you a bit disappointed, wouldn't it.  

[Brooke]

The determination that a structure that is deemed safe  at x speed and y deflection is some how not safe at any higher speeds at 1/2 to 1/45 y deflection can not be reconciled with real world physics.  As far as documentation goes it would be silly for the poh to offer more than a max deployment warning for landing on the 109 because it had no other fixed settings.  Should they post numbers for every degree of deployment?   Also I fail to see how a procedure that is simple enough to use at low speeds and altitudes somehow becomes more complicated with altitude and speed.

Restricting the FDS by POH (while ignoring the basic physics involved) in an air combat simulation is like a rally racing game limited to the car's operators manual.  It may be easy to justify, right up to the point where you see the actual real world operation of a rally car by a rally car driver in a race extracting the maximum possibilities from his vehicle.
Once you see the truth the video game would leave you a bit disappointed, wouldn't it.  

Some airplanes have information in pilots manuals and/or flight-test data that give flap deployment speeds for different settings of flaps.  My guess is that HTC does not pick flap-deployment speeds arbitrarily but instead based on information they have.

Here's a video of using flaps in one model of 109 -- doesn't look like it would be too easy during a dogfight.  http://www.youtube.com/watch?v=qcMjhihuuX8&feature=player_embedded  In AH, all we have is the keyboard, so it's easier in the game than in real life, but then flaps are restricted to several discrete settings, rather than continuously variable on the 109 that has continuously-variable deployment.

[GScholz]

Here's a video of using flaps in one model of 109 -- doesn't look like it would be too easy during a dogfight. 

Why would you say that? The wheel next to the flap-wheel is the elevator trim-wheel, which the pilot would have to use in combat. The position and side-by-side arrangement of these wheels were considered a good feature in the 109 cockpit since it allowed lowering flaps and trimming for flaps-down in one motion with one hand (109 became nose-heavy with flaps down).

[Brooke]

Flaps allow more lift at slower speeds but with a substantial penalty of drag and do not allow higher angle of attack.

Slats allow more lift at slower speeds by allowing more angle of attack to be utilized.

My argument is . . .

Angle of attack is not the important factor.  Both devices alter the lift and drag profiles of the wing, and what ends up being important are things like what C_L_max is (at whatever AoA), and what max L/D is (at whatever AoA).

Also, I don't think that there is a way for anyone, by feel in the game, to figure out whether or not flaps or slats are incorrectly modeled (unless they are drastically off, which I doubt).

I don't have the exact numbers but neither does anybody else on this thread.

Years ago, there were arguments that "the F4U turns better than it should, especially with flaps."  These arguments were made by folks based on feelings and personal intuition, but without any knowledge of the basics of aircraft dynamics.  So, I decided to take a crack at it using standard, well-accepted aircraft dynamics to see if they agreed with the performance shown in Aces High -- including stats with and without flaps deployed.  They do.  It is also a decent overview of some basics of aircraft dynamics:

http://electraforge.com/brooke/flightsims/aces_high/stallSpeedMath/turningMath.html

I could probably do the same picking a 109 and including the modeling of slats.  I'll look at it at some point and, if it's not so much work, I'll take a crack at it.  First, though, I'll probably work on adding more accuracy to my analysis given above (adding some more-picky factors to it, making it more akin to this: http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19930092640_1993092640.pdf).

In case of any interest, some of my favorite books on aircraft dynamics.

Airplane Performance Stability and Control, by Courtland D. Perkins and Robert E. Hage
Theory of Flight, by Richard Von Mises
Fundamentals of Flight, Second Edition, by Richard S. Shevell.
Aerodynamics Aeronautics and Flight Mechanics, Second Edition, by Barnes W. McCormick.
Introduction to Flight, by John D. Anderson, Jr. (best introduction to the field of all books of this list)

[Brooke]

Why would you say that? The wheel next to the flap-wheel is the elevator trim-wheel, which the pilot would have to use in combat. The position and side-by-side arrangement of these wheels were considered a good feature in the 109 cockpit since it allowed lowering flaps and trimming for flaps-down in one motion with one hand (109 became nose-heavy with flaps down).

It's based on how cramped it is for the left hand and how many turns it takes.  Yes, you could maybe do a crank or two in and out, but I don't think you'd be going in and out of full flaps (or even half flaps) in a dogfight with it like we commonly have here.

[GScholz]

No, full flaps wouldn't even be useful in real life combat. "Combat flaps" however could be achieved with a couple of cranks on that wheel.