Landing help corsair!

[VOODOO]

If you watched the video link I posted you can see the aircraft goes into ground effect which gives more lift, nose goes up, out of ground effect , STALLs back into ground effect and back into ground effect, out of ground effect, stall to crash. Ground effect is just what fhuber said. "Ground effect will ADD lift, not cause a stall. Ground effect is essentially the "squeezing" of air between the wing and the ground". Which does not cause the stall but if you let the new lift take your nose up you bleed your airspeed and once you come out of ground effect stall will follow. cause and effect.

John

Afraid I must disagree with the assumption that ground effect caused the CORSAIR stall in the video. There is no ground effect at the altitude this plane started it's loss of control. About half the wingspan above the ground is where you might begin to feel the effect. Also, it is not a sudden, hit the wall experience, but comes on gradually, and increases as you get closer to the ground. My take on that video is it was caused by overcontrol, like many landing accidents.

[wrongroad]

G'day Zeo,
One tip to judge your airspeed, and this does take practice and lots of it, is to use your base leg on approach to get an idea of the speed of your model. After a while you will get the 'feel' of the speed from this part of the landing phase.
My FMS V3 Corsair gives very little notice of a stall except for a tiny amount of wing rock just before. Miss it and your model is rolling over and heading to the deck.
You tube has many videos of bad take of and landings of F4u's of various scales and power and they all look the same. Lack of airspeed is the main culprit most of the time.
Another thing to look for with the F4U is, as mentioned here before, tail drop during a turn. It is a sure sign of low airspeed and the result is often that the Corsiar will suddenly reverse its direction by rolling against the turn. IE, rolling left if you are turning right. The model will drop like a rock and be in a terminal stall with not enough air flow over any of the control surfaces to recover. And the machine is now often in a tumble as well. Time for the garbage bag:@:angel:.
I find the FMS 1400mm Corsair is easier to land with a fraction of nose down trim dialed in during the down wind leg. I do not mix in any nose down with flaps or any thing else as I like to be able to do any settings as required for the situation at hand.
The rest of the advice that has been given is sound.

G'day Voodoo,
I have been reading data from Airbus industries that is basically saying that ground effect may not be as much of a deal as previously thought.
Their reasoning and data seems to indicate that all the ground effect simply bleeds out from under the wing as there is nothing to restrict or retain the pressure under the wing.
They indicate that there is still some effect but nothing to what generations of pilots and engineers have been thinking.
It makes some sense to me as the ground effect Formula One cars of the eighties had skirts around the cars to restrain the vacuum that the aerodynamic package was developing. The simple way to prevent ground effect was to remove the shirts and therefore remove the 'fence'.
It is a good read and if I can find it again,[I did not think to book mark it and only found it by accident when I was wide awake at midnight a few years ago and at least one computer ago:D] I will post the link but it was related to the design work on the A380.
Regards and respect
Daryl

[JFandL]

Afraid I must disagree with the assumption that ground effect caused the CORSAIR stall in the video. There is no ground effect at the altitude this plane started it's loss of control. About half the wingspan above the ground is where you might begin to feel the effect. Also, it is not a sudden, hit the wall experience, but comes on gradually, and increases as you get closer to the ground. My take on that video is it was caused by overcontrol, like many landing accidents.

VooDoo,

you don't need be afraid to disagree with me, that is a good thing that you pointed out the stall (Flip) was to high to be in ground effect. Ground effect started the pilot's errors until aircraft crashed. Also there is nothing to fear about ground effect, a good pilot can and will use it to better control an airframe on landing(knows it there and how to adjust for it). My take on that video is wrong input by the pilot at the wrong time caused the crash, due to his lack of understanding what the 1st effect was or how to adjust to it before to late happened.

John

[zeo]

I just did some training on my flightsim aerofly 7 on my macbook with a spectrum radio and figured out it is easier to use flaps on landing with 20-30% power. The corsair simply glides in so easily! I hope it works the same way on the field.

[XF-15DCC]

You might need to mix your flaps with a stab input. Get 3 mistakes high and see how the plane reacts with the flaps down before trying to land with flaps.


Kevin

[zeo]

Yes XF-15DCC good idea, getting higher up to see how the flaps react before doing the real landing will help me gauge the plane speed.

[fhhuber]

Really its ALL about learning the glide characteristics of your aircraft.

Small deflection (5 to 10 deg) flaps is a minor drag addition with lift improvement. (usually exhibits nose-up with speed, but it is speed related and flaps are for when you are slow)
Moderate flaps more lift and drag.
More deflection after a certain point (close to 30 deg) tends to just add drag and may actually reduce lift depending on the style of flap.

Split flaps tend to give more drag and less lift.

Understanding how flaps affect the model will help you choose how much deflection to use for the current flight conditions.

Usually we are left with a 2 position or 3 position switch operating flaps.
2 position its easy to just have none vs too much as your choices.... better to pick a moderate (15 to 20 deg for start, adjust from how it flies) flaps down position.
3 position you have none, some and max.... A small to mild moderate (5 to 15) as mid position and high moderate (near 30) for max deflection usually works well.

Flaps on a slider/knob... I try to come up with a way to put appx 3 intermediate detents I can feel "click in" Full flaps rarely gets used if its more than 35 deg.

[benjack71]

I have a red bull corsair(beautiful plane!) from horizon hobby that I just did my maiden flight on recently. I had someone takeoff and land fine with no issues. When I got the controls I was able to fly fine and reduced the power to about 15-20% or so and was close to landing however about a few feet off the ground she just dropped like a brick and the landing gear collapsed and a prop blade broke. No damage to the structure of the plane though. Got the gear fixed and new prop blade is coming in soon and should be fixed soon to fly again. I need to know if I should land with 50% power instead? I guess war birds needs plenty of speed on the landings. I am just worried about doing a hard landing. Any suggestions?

I am about to get slammed by everyone on here. My first bit of advice. Leave your flaps alone. Do not use the flaps. Learn to land that plane, on its mains without flaps. Your going to set up and do a low flyby over the center of that runway. Your going to put your mains down and do another low flyby over the center of your runway. Your going to circle again, this time as your doing your low fly by, your going get a little lower. Your going to fly that airplane, with some speed (yeah half throttle most likely) about a foot off the deck. Then your going to cut the power. That plane will settle on the mains. Let it run out, dont jerk on the elevator. Slightly apply some up elevator as it is running out. As it is slowing, increase the up elevator. Your back wheel touches. Your down. Learning to fly on a high wing trainer type plane is great. Most of us did it. It does not prepare you for a Corsair worth a darn. Of all the prop warbirds a corsair is the hardest, most rewarding, break your heart, beautiful thing in the air. Keep landing like that. After your proficient, start using HALF FLAPS with the same approach. Look what you got to do is get this notion of landing like a cessna out of your head. You cant be real high, and setup with your flaps and float it in like a high wing plane. Which brings another point. Altitude and cutting corners. When your going to land get that plane down. Dont set up on your final way high thinking your going to float it in on the flaps. Its a corsair not a high wing. Get your self straight with the runway. Do not cut the corner. In other words take your plane PAST the end of the runway, turn it back toward the runway. Do not turn your plane where it cuts the corner of the runway. Once you get past your runway, and you make your turn, then line that plane up with your chin. Yes, I mean line that plane up with your chin, where you are standing. If your still to high, go back around and line it up with your chest. Get that altitude down and dont cut that corner. Ok, so your lined up on yourself. I know, your thinking that is just dumb. Tell you what. I would bet you a dollar bill when you line up on your chest, you end up in the middle of that runway with virtually no adjustment almost every time. Try that trick once with a easier plane to fly and see if it does not work. Another thing to remember. Do not lower gear or play with flaps until you are lined up on your approach. Dont put wheels down and flaps down then start making your turns. Eventually you can play around like that, but for now, just say no to that. That is my bit of advice.

[Prowler901]

Hi Ben,

Could you elaborate further on what you mean by lining up on your chin/chest. I'm having trouble visualizing what you mean.

Thanks,
Todd

[WintrSol]

I am about to get slammed by everyone on here. My first bit of advice. Leave your flaps alone. Do not use the flaps. Learn to land that plane, on its mains without flaps.

My FIL flew P-40s and P-51s in WWII; we asked if he ever used flaps, and he said he never did.

[wpmay]

I am about to get slammed by everyone on here. .............. Ok, so your lined up on yourself. I know, your thinking that is just dumb. Tell you what. I would bet you a dollar bill when you line up on your chest, you end up in the middle of that runway with virtually no adjustment almost every time.

Your whole post was excellent and the quote above is the exact advice that one of the most experienced pilots at my club gave me when I joined four years ago. When you turn on final you should aim the plane directly toward you and it will ensure that you get your plane on the runway/field every time. Naturally, as the plane gets closer to you and the field you will automatically turn it slightly away from you but you will do that without even having to think about it. I can't tell you how many times I have seen other pilots (and myself) end up landing on the far edge of the field or even off it because we're trying to land "parallel" to the field and misjudge the plane's position until it's too late. Aim it directly at yourself when you make your turn to final and your plane will end up on the field/runway even if it's the first time you've ever landed there. Great advice for new or experienced pilots.

Bill

[benjack71]

Hi Ben,

Could you elaborate further on what you mean by lining up on your chin/chest. I'm having trouble visualizing what you mean.

Thanks,
Todd

Sure. You turn your head to the left to watch your plane come down the center of the runway, or you turn your head to the right. Lets set this up this. Your RC Runway runs North/South (most usually do). If your APPROACHING from the north, your head will be turned left. If you line that plane up on your body you will put that plane right over the middle of the runway almost every time. So when I said chin high, I meant you want to have that plane lined up on your body, as your head is turned looking at that plane approaching to land, have it lined up to appear about chin high. If you find that your still to high and eating up to much real estate punch it and go around. This time line it up chest/abdomen high until you get that altitude for approaching just right. Of course this can be adjusted for the length of the field your flying on. The shorter the runway the lower you want to be as you approach generally speaking. The biggest problem I see with landing a warbird especially a Corsair is coming in to high and trying to float it in on flaps. Examples.
My home RC field is really long, its close to 600 feet. But, you can see I had power and speed and got that altitude down to level flight. There was no attempt at "floating it in on flaps". Hangar 9 50 size corsairs do not have flaps. Landing at 530 mark.

https://www.youtube.com/watch?v=NXHa-lKjV4w

Example two without flaps. Hangar 9 60 size Hellcat. landing starts at 515 mark

https://www.youtube.com/watch?v=rurqzv1eDQs

Final example with flaps. Its hard to see but I made a mistake and I cut the corner. Notice how I ended up having to correct for that. Had I brought it lined up on my body, I would have avoided that correction. The thing to look at though is even with my flaps deployed, I have power going and I am flying that plane down to the deck. I am not depending on that Corsair to float in on those flaps. Where the flaps came in handy, was at slightly less than 1 ft. off the deck, I raised that nose slightly and cut power, at that point the air braking of the flaps caused the plane to slow at just the moment the mains were touching down. Start landing at about 830 mark. Topflite 60 size corsair.

https://www.youtube.com/watch?v=IvGoRRe99oA

[Prowler901]

Alright. I see what your sayin' now. Thanks for the clarification and the examples. Very helpful. :)

Todd