Hey you guys:
I am planning on flying a new Corsair this Sunday.
It's the CMPro 75.5" with flaps.
Does the use of flaps help stabilize an aircraft and help it overcome the thrust factor?
thanks


Tom

What's "the thrust factor"?

The use of flaps will help stabilize all warbirds on landing. There are some good discussions about flaps in the aerodynamics forum.

I wouldn't consider landing my warbirds without full flaps. Depending on the particular manufacturer, they can be very effective in allowing you to maintain steady, stable control of the plane at (final approach) speeds slower than you could fly without flaps. This makes landings much easier for the pilot AND less stressful on the airframe.

If you'll tell me what you mean by "thrust factor", I'll try to answer that too.


Mike

I think he means the torque and or left thrust produced by most tail dragging warbirds ? If not ,,, I'm all ears.
If that's what Tom is talking about the answer is no. You still have to use the rudder with throttle input on takeoffs, etc, etc.
And I wouldn't use flaps on roll out either. You may just rotate quicker than you'd like to.

Not to disagree with anyone, but if you come in for your first landing and flip the flaps full down, you will think ANYTHING BUT "stable."

Try them in the air, up high. See how much elevator you have to push to attain level flight, with flaps down at a slow speed. Then try landing.

Good luck,
Dave Olson

That's why you need to slow down the rate at which the flaps are deployed. When I hit my flap switch, it takes 3-4 seconds for the flaps to fully drop, and the plane becomes "rock" stable afterward.

Wanna see some examples of flapped landing? Check out the videos on my website. Your retracts and airframe will appreciate you IF you learn how to use flaps correctly.

Tom, you may have opened a can of worms here! The purpose of flaps is to increase lift to allow a slower landing speed. Period. Now on jets, it also has the benefit of increasing drag which allows the engine to maintain a higher thrust, and less throttle lag, which comes in handy should you need to go around, but this is not a factor with piston powered aircraft. Use of flaps won't change the inherent stability of your aircraft; it's just as stable (or unstable) with flaps as without. What happens that you naturally fly nearer the stall speed with flaps, so it may seem it's more unstable; which it can be in that part of the envelope, but it has nothing to do with the flaps themselves. Use of flaps can change your trim, and the faster you crank them out, the faster you notice the change. Best to go slow, and try different amounts of flaps. Depending on your wing loading you may find more or less flap works best for you. I fly a Topflite GS Mustang, and with full flaps it floats too much form my taste, and I usually only use about 1/2 flap to land. I also fly a Topflite GS Corsair that weighs 36# (!), and I can land it with anything from no to full flap. Of course there is a noticable difference on approach speed and the amount of roll out distance, but the point is I dont NEED the flaps, but the do look cool, expecially on a Corsair.

Depending on the design and throw flaps will increase lift and add drag. Split flaps seem to add a lot of drag. Slow and draggy my planes get a bit mushy. I deploy flaps slowly at about 1/4 throttle and before final. I let it settle make my turn and let it come on in. They can real nice on a calm day.

Carl

The increase in drag is an important consideration, and the flaps on the Corsair do add considerable drag; chopping the throttle abruptly with full flap is not recommended! As you say, I like to keep about 1/4 throttle with full flaps, set my attitude, and control decent with power.

The old rule of flaps is the first 20 degrees adds lift after that its just drag. This is why on a fowler flapped airplane you can use upto 20 degrees of flap on takeoff. On a split flap airplane such as a P40, the flaps do add lift but generate more drag than anything else which helps steepen your approach and allows you to make a nice stable power on landing. If you have a heavy slippery airplane you will see the most benefit. light wing loading with alot drag ie most sport planes we fly really don't benefit much from flaps.

I wasn't trying to open any cans, be it worms or corn. I was curious if flaps down during the take off roll and lift off would help stabilize the plane from the left thrust. I've added 3 degrees of right thrust and one degree of down thrust at the engine. I've seen the real thing take off and land with full flaps. Why not a model?
I've used flaps on my Cessna 182 Skylane on take off and landing and I mixed in down elevator to minimize the ballooning effect.

Anyway the first flight will have to wait a week or so until I can install a better linkage for the flaps instead of the lousy set up that came with the ARF. They used stranded cable inside a less than perfect guide tube that would flex when pushing the flaps up which would have no constant end point.
Guess I'll have no choice but to install bellcranks or to make a box for a servo on each side.


Happy flying!!


Tom

Flaps can add stability becasue they increase lift. When they increase lift you reduce the AOA of the wingtip, enabling you to fly slower without tipstalling.

I always use flaps to land my Spitfire. I put in full flaps and then approach steeper witha lower nose than with my other planes but because of the flaps the the plane does not gather too much speed. I find that much safer than coming in low and slow.

A P40 has split flaps which add to much drag to be useful for take off. A Cesna 182 has fowler flaps which do not start adding alot of drag untill you go over 20 degrees. I would leave the engine thrust angles at the Top flights specs for now and play with them after you have got the plane in the air and sorted it out. There is no majic bullit when it comes to these warbirds. I would suggest that if you are not comfortable flying airplanes which require alot of rudder on take off, that you fly something else for a while. These Top Flite P40's will eat your lunch if your not a good pilot. This is not a Hanger nine P40 by any stretch of the imagination. My Top Flite Bearcat usually takes full right rudder on take off and even then it may not be enough in a cross wind. My Old top Flite P39 was the same way. You really begin to understand what that rudder stick is for when your doing the dance on roll out after landing. By the way nobody takes a plane off, real or model at full flaps.

Hey:
Well I flew the Corsair today without the flaps. The flaps are on the plane, but not functional until I can rig up another way to control them from what came with the ARF.
WOW is an understatement! Roll out was a bit touchy cause we had a bit of a cross wind and it wanted to weathervane but once in the air it flew great. Nice Corsair like rolls, biggggggggggg loops and had plenty of speed.
My knees were shaking so bad I didn't have the guts to try much more.
The thing flew on about 1/3 throttle.
The retracts worked flawlessly and it looked so clean on a low pass.
I'm very happy with it's performance.
One concern I have is the tail doesn't want to leave the ground without hammering the throttle.
Another concern is it is hard to see sometimes.

Happy Flying

Tom

PS: Now I can add the decals and do the weathering.

One thing I forgot to mention. My flaps are indeed split but I put webbing between the inboard and center flap so when they are down there is no gap
I sure hope the wife doesn't miss her amex card!!!


Happy Flying

Your Corsair does not have split flaps, Look at a P40 sometime and you will see the difference. On a split flap the top of the wing stays in place and only the bottom lowers therefore the name split flap. I generally take my warbirds off by easing into the throttle without holding any elevator and pouring the coals to her when she can handle it without nosing over, let the tail come up on its own and let it run as long as you can, lift off and then do a relatively flat climb out just like a real one. Safer and looks better to. Holding elevator on take off role is a good way lift off early and snap role into the ground.

I think he meant the flaps seperate into three pieces as they are lowered, right? Many Warbird models have a flap option. A scale Warbird benefits greatly from flap useage. However, I have a Great Planes F4U Corsair without flaps and doesn't need them as this is a Fun Scale airplane. It's an ideal First Warbird. Easy to take off, fly and land. I have more Scale Warbirds that I do use the flaps when landing. This is something good to practice on your simulator at home. Put in variable wind conditions and practice landing with flaps. Once you get the hang of it, you'll see how much more realistic your airplane looks when landing. Not only that, but crashing on the sim doesn't cost you anything. One more thing; don't forget the Warbird has a very useful control surface called a RUDDER. Please use it!

Thanks Slow for the correction. I like learning without it costing me anything. One thing I am going to argue is that real corsairs employed flaps (whether full flaps or not I'm not sure) to take off from carriers in WWII and I have a pic to prove it if I can scan it and post it I will.
Did you also know that the real pilots of the day used the landing gear as speed brakes?
The gear wouldn't lock unless the aircraft was at a certain speed.
There were 12,000+ corsairs built, they had a 11-1 kill ratio. They were also the first prop plane to reach 400 mph and catch the Zero.
Anyway I have the info I need and will be installing the flaps one I get a couple of servos and start cutting.
Can't scan the photo *&%$*&Y)(&^.


Happy Flying


Tom

Every one is correct,although you might disagree with that!!! Tom

No!!, but I may agree to disagree!!! lol