Flaps.. I can't find any lift.

[Lephturn]

I have been doing some more testing of the F4U-1D in the Training Arena trying to find any benefit to flaps.  I can find none.

The drag is there, but I cannot find any lift benefit to the flaps.  Here is what I have done, please let me know if I am doing something wrong or missing something.

1.  Stall speed test... climb at full power at increasing angle until minimum speed is reached.  After the AC has stabilized, I try various flap settings to see if I can keep the nose up at a lower speed with flaps.  I cannot find any benefit.  I can climb at just as low a speed with no flap as I can with 10,20,30% or max flap.

2.  Min level flight speed test.  I cruise along at 200 feet and slow to 120 MPH to start the test.  Back off the throttle and watch the VSI to maintain level flight.  I can maintain level flight at about 105 MPH at best.. with or without flaps.  Engaging varying degrees of flaps does not lower my minimum flight speed, even momentarily.  The hog should be able to fly much slower with flaps... these things are HUGE!

3.  Turning tests.  On the deck, turning 360 degree turns endlessley.  Adding any amount of flaps at any time, even for a short period, only slows my 360 degree turning time.  Turning radius is unaffected as well.

I haven't tested any other birds, only the F4U-1D.  Still, I can find absolutely no benefit to the flaps.  Am I missing something?  Shouldn't minimal flap settings increase lift with not a lot of drag?  I don't even see a momentary increase in lift when I deploy flaps.. only instant slow degrading due to the additional drag.

Right now all flaps can do is slow you down, at least in the Hog.

------------------
Lephturn - Chief Trainer
A member of The Flying Pigs
Visit Lephturn's Aerodrome for AH news, resources, and training data.
 http://users.andara.com/~sconrad/
 

"MY P-47 is a pretty good ship
And she took a round coming 'cross the Channel last trip
I was thinking 'bout my baby and lettin' her rip
Always got me through so far
Well they can ship me all over this great big world
But I'll never find nothing like my North End girl
I'm taking her home with me one day, sir
Soon as we win this war"
 - Steve Earl

[This message has been edited by Lephturn (edited 03-03-2000).]

[Minotaur]

Leph;

I have been doing some flap testing myself.  Testing mostly to find a repeatable method of landing.  This is so that I can teach new players how to land in AH and provide a detailed document for doing so.  

Lately my testing has been in the P-38, my bird of choice.  The P-38 is not an easy bird to land.

Please note that I am not a pilot in RL and I am often prone to misconception.  

Here is what I assumed about flaps:

• For most planes the nose should pitch down when flaps are applied.
• P-38 is one exeception that I know of where the nose might pitch up especially if inverted
• A/C with manuvering flaps like the P-51 or F4U for the 1st 20-40% of deployment are also exceptions
• Full flap deployment should induce alot of drag
• Flaps should add lift to the wing

Flaps should:

• Keep the nose low enough to be able to see the runway when landing
• Keep the speed below the maximum speed for lowering the landing gear
• The stall speed low enough to allow the A/C to fly under control on approach
• Landing speed low enough to allow the A/C to stop on a reasonable length of runway

Things that I know are important to landing:

• Airspeed
• Rate of Descent
• Angle of Attack
• Touching down on the main gear

(Glide Slope = Airspeed + Rate of Descent)

This is the way I thought landings should be:

• Turning onto final I should be about 500ft AGL, 150mph, with 60-100% flaps deployed
• My AoA should be about neg 5-10 with the nose pointed at the nearest end of the runway
• Deploying more flaps as needed to control speed at 150mph or less
• When speed drops below 150mph drop the gear
• The nose should pitch down with a noticable drop in speed
• Pull the nose back up
• Maintain an AoA of neg 5-10
• Descent rate of 500fpm or less
• If the glide slope is too low lift the nose a little and throttle up, if the glide slope is to high then vice versa
• Flaps and gear down allowing the nose to be low and speed to stay under 150mph
• Keep the nose pointed at the nearest end of the runway or just in front of it
• Speed about 125mph
• At 100-150ft AGL rotate until the AoA is pos 1-3
• Descent rate of 300fpm or less
• Piont the nose at the far end of the runway
• Rotate to an AoA of pos 10-15
• Descent rate of 150fpm or less
• "Stall horn .. STALL Horn .. STALL HORN"
• Dscent rate of 50fpm or less
• Speed 100mph
• Stall
• Touchdown
• Apply the wheelbrakes

Problems that I have doing this:

• Even at full flaps and gear down, I can't stay slow enough unless I keep an AoA of pos 10-20
• Can't see the runway with high AoA, even using a turning approach
• Very hard to control speed with a high AoA
• Very hard to control descent rate at low speed

Basically I am coasting down blind to the runway, a high AoA with the stall horn blaring the whole time.  

I can get the plane down, don't get me wrong.  My best results use a long shallow approach to drop speed, with a very low neg AoA.  This kind of goes against what I believe to be the grain of a good landing.  Relying almost totally upon engine Hp and prop thrust vs controlling the descent rate using the above mentioned method.

Previously I might just skid the heck out of the A/C to control speed.  The P-38 will not skid very well at all.

I'll take all criticisms and any help that I can get.  Thanks in advance!          

------------------
Mino
The Wrecking Crew
Trainer

[This message has been edited by Minotaur (edited 03-03-2000).]

[funked]

Flaps caused an upward pitching moment on some planes.

Otherwise I agree, landings seem weird.  To keep the plane slow enough you need a combination of high AoA and low glideslope angle that makes the runway invisible.  I just fly curving approaches.  However I have read more than a few real life pilot comments about poor visibility over the nose on approach, so maybe it's right.

[Sorrow[S=A]]

No, it's not really too right. The flaps are NOT giving us extra lift. We are supposed to land the average fighter at 90 mph. As a matter of fact most of these guys should shear a gear at over 150 mph. However we have airbrakes instead of flaps here. All the drag no lift. At 110 mph the 109 feels like it's a stone dropping out of the sky with 20 degrees  flap, yet 20-30 degrees and 90 mph was the desired landing setup.

BTW for the P-38 I found the EASIEST way to land is to remember it has a tripod gear. stay at -3 AOA and use full flaps plus a hair of throtle to keep at 130 mph until you are 50 ft off the runway. Then flare that baby like an F-16. Chop throttle pull back, push forward and drop onto a 3 point landing. I have yet to miff one yet. You can not land nose down on her, couldn't do it in real life either.

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If your in range, so is the enemy.

 

[This message has been edited by Sorrow[S=A] (edited 03-03-2000).]

[Minotaur]

Well, HTC was ahead of me again.

The installation of ver 1012 fixed alot of the problems I was having.  I can now skid the P-38 to slow down and E retention at lower speeds seems less.  But, IMO you should only have to skid if you come in hot or too high, otherwise flaps should maintain a low approach speed.

I do feel the flaps need more work in the FM.  They don't feel right, don't ask me how I my know this.  They just don't.  




------------------
Mino
The Wrecking Crew
Trainer

[funked]

Heheh Sorrow I think you are right.

My problem is that I have been doing too many landings in Falcon 4.  I'm used to planes that need a high AoA and feel like a stone dropping out of the sky.  

[MiG Eater]

 

Originally posted by Lephturn:
I have been doing some more testing of the F4U-1D in the Training Arena trying to find any benefit to flaps.  I can find none.

The drag is there, but I cannot find any lift benefit to the flaps.  

Thanks for checking my observations from the P-51 torque-(turned F4U flap discussion) thread.  I also tried some flap vs. no flap take offs and found little or no difference in take off run distance.  There is slightly decrease acceleration due to the increased flap drag.

MiG

[Lephturn]

Missed your earlier post MiG.  

Glad to hear I'm not the only one who's noticed that there is no lift component when you deploy flaps.  So you tested the 51, I tested the Hog.  I'd bet it's accross the board, but I'll check a couple of other planes just to make sure.

------------------
Lephturn - Chief Trainer
A member of The Flying Pigs
Visit Lephturn's Aerodrome for AH news, resources, and training data.
 http://users.andara.com/~sconrad/
 

"MY P-47 is a pretty good ship
And she took a round coming 'cross the Channel last trip
I was thinking 'bout my baby and lettin' her rip
Always got me through so far
Well they can ship me all over this great big world
But I'll never find nothing like my North End girl
I'm taking her home with me one day, sir
Soon as we win this war"
 - Steve Earl

[This message has been edited by Lephturn (edited 03-06-2000).]

[Hangtime]

Hunh... thanks Lephturn for this thread!

Did some quick and dirty tests with the P51.. and saw some diffrences.

Agreed; no discernable lift; however it would seem that I can hold about 3 degrees higher AoA at stall on combat flap w/the P51.

No discernable climb improvemnet, but when light on fuel that 3 degrees higher AoA seems to give me shots I woulda missed; hanging there clawing up on my prop...

As for landings.. I love just pullin the nose up about 15 degrees and holding at idle till she gets sluggish and begins descent, 2 notch flap; gear down at 150. I stay cross controlled till just short of touchdown; and continue to feed in flap; and gently goose the throttle to slow the descent rate..

Had some nice no-bounce 3 pointers.... ;0

Hang

[Duckwing6]

yea i know about those extra 3° AOA you're talking about just too well Hang  

[Lephturn]

Hangtime,

I wonder if that extra tiny bit of AOA is due to the effect flaps have on your trim condition?

Also, in regards to landing, it's a damn good thing the F4U's gear is so tough.  If we ever get a carrier it will be really tough to set a Hog down on it without the flaps being fixed.  I don't wanna see what would happen if you tried to drop one on the deck at 110 MPH.

No lift from flaps is a large problem for me in the Hog.  When I've evaded a higher attacker and he's worked me to the deck, the only thing I have left is decent low-speed maneuverability.  With flaps, I should be able to out-manuever a P51 at low speeds.. but I can't right now.  The flaps should lower the stall speed to 80-90 MPH and give me additional lift.  Not to mention the better turn rate I should have with 20 degrees of flap popped.

Maybe it's different in each plane... but the flaps on the F4U are broken.. they are only good as air brakes and nothing more.  

------------------
Lephturn - Chief Trainer
A member of The Flying Pigs
Visit Lephturn's Aerodrome for AH news, resources, and training data.
 http://users.andara.com/~sconrad/
 

"MY P-47 is a pretty good ship
And she took a round coming 'cross the Channel last trip
I was thinking 'bout my baby and lettin' her rip
Always got me through so far
Well they can ship me all over this great big world
But I'll never find nothing like my North End girl
I'm taking her home with me one day, sir
Soon as we win this war"
 - Steve Earl

[This message has been edited by Lephturn (edited 03-08-2000).]

[Hangtime]

Hiya Lepth!

>>I wonder if that extra tiny bit of AOA is due to the effect flaps have on your trim condition?<<

Certainly.. this is so.

>>I don't wanna see what would happen if you tried to drop one on the deck at 110 MPH.<<

I do. I'd pay money ta see that.   Film would be worth somethin too. Muhahahhaaaa!

>>With flaps, I should be able to out-manuever a P51 at low speeds.. <<

Hmmmmmmmmm... Thats highly debatable IMHO.  (assuming flaps work the same in both planes)
I'd sure like ta give it a try. For that; I'm already payin thirty a month.  

>>Maybe it's different in each plane... but the flaps on the F4U are broken.. they are only good as air brakes and nothing more.<<

Cheer up. It's porked in all planes across the board I bet. Certainly is in the P51; B26 and C47. Mayhaps 'porked' is too harsh a word.. I initially just figured the AH Mustangs flight model was more refined; but it turns out I was just 'conditioned' by it. (Awful lot of hours flyin it)

Shall we call the flap portion of the AH FM 'unfinished' or 'developmental'??

I mean; since we're outta "beta" and all, that term would no longer be appropriate..  

Hang
TDY/357th Pony Express

[Pyro]

We went looking into this today and did find a couple of problems in the flap system, one of which was causing the problem mentioned in this topic.  It'll be fixed in the next version and makes a marked difference.



------------------
Doug "Pyro" Balmos
HiTech Creations

"If it's stupid but works, it's not stupid."

[indian]

Vulchamatic getting more tunring ability.

------------------
Tommy (INDIAN) Toon
  1st Aces High Trainer Crew
Home of The Allied Fighter Wing A.F.W.
A.F.W. Homepage

[funked]

Outstanding Pyro!