Looking for some advice.

Flying a new plane designed by a friend in Texas that is on the heaving side.

Landing this plane without a head wind has proven to be a challenge due to the high landing speed required to avoid a stall.

Mixed in flaps last night and will try flying again this weekend.

So much for painting the picture, now to my questions:

What do I need to keep in mind during landing?

Do I need more up or down elevator than normal to sustain level flight?

How much flap should I start with? 20%, 30% ?

Any nasty flight tendancies when flying slower speeds with flaps?

Help.

GB

Watch your speed. It should be high anyway, with a heavy plane.
Flaps let you come down steeper more than slower.
Getting slow with flaps is just as bad as getting slow without them.
As for amount of travel and how much to trim, start with about 30% down, and at a decent altitude, but not fast, drop them. Observe which way the plane pitches, and how much elevator you have to hold.
Then pull the flaps up and land, and adjust the elevator mix to the same amount of stick.
For the next flight try 50-755 down flap and observe the elevator.
I generally just hold the elevator required, I don't mix it in.
Back at altitude, check what happens with full power. Sometimes the pitch-up is too much to control with elevator, only pulling the power back will prevent a stall-spin.
If that happens with your airplane, don't do that no more!
Flaps are not a cure-all for making a heavy plane fly slower, or better. It still must be flown properly.

Thanks for the detail.

Will keep it in mind tomorrow at the field.

The plane lands just fine in a head wind but with no wind it comes in hot, I can get it down ok but as soon as I touch down the wheels seem to grab (wire gear mounted in the wing with wheel center even with LE of wing) and the tail comes over and impacts on the top of the rudder (plane now upside down and at a full stop [:@])

FAA boys would call that one a CFIT (controlled flight into terrain).

Sounds like flaps may not help in this case from your description.

Any other ideas?

Thanks,

GB

Flaps will allow you to come in slower as the give you increased lift at a slower ground speed. The key thing to remember is that no airplane will stall if the nose is below the horizon or the wings center of lift. If you can see any of the top of the wing, it won't stall! When on the downwind approach with flaps you find the speed thats comfortable to easily maintain altitude and controllability. When on final you use the throttle to maintain you rate of descent. Less throttle to come down faster, more throttle to slow the rate of ascent. Dont start chasing the altitude with elevator, but use the throttle! The ailerons are used to keep the wings level only and the rudder to maintain course and alignment on the runway. This all can be practiced at altitude with a simulated landing approach. When you are landing hold the slightly nose down atitude until about 6 to 8 foot from the ground, then slowly pull the throttle back to idle and flair slowly as yuu get closer to the ground. You should be at idle when you make the final flair. If you do decide to go around, dont push the throttle full forward in an abrupt response. It may cause a danderous nose high condition. Push the throttle forward carefully and manage your pitch. When you have reached a safe speed and attitude then you start slowly raising your flaps. I really think when you are proficient with the flaps you won't fly without them.

Landing attitude with flaps... done properly, it looks like this..

Thanks guys.

Now for some practice.

GB

Hi,
I've moved the post to RC Humor:

http://www.rcuniverse.com/forum/fb.asp?m=2167046

If you look at most flap design most are designed to add lift at 7-15 degrees. Then at the higher levels of 20-35 degrees you end up with more drag than lift. Stall speed are only a result of the true angle of attack relitive to the models movement thru the air. Fowler flaps create more wing area and greatly let you slow the plane down for landing. I test all of my 1/2 scale planes in a sim that you can buy of the web called X-plane. It will let you build any aircraft from models to full scale and test your design. It has helped me with everything form cg, stall speeds and wing designs.

Stall speed is related to angle of attack and airspeed, but there are other factors, including wing loading. Dropping flaps alters the angle of attack of the wing without having to pitch the nose up; when the trailing edge of the wing lowers, the mean chord line (a line drawn through the wing from the center of the leading edge to the trailing edge) is angled more sharply to the relative wind, increasing angle of attack along the span of the flap. It does nothing to increase lift on the wingtip beyond the end of the flap, so flap performance on your plane will depend to a great degree on the "flap span" vs. the total wingspan. Lift may increase with partial flaps, but beware of higher settings if you have relatively narrow (span) flaps, because the tips beyond can stall if you get slow enough, even though the inner portion of the wing is still generating adequate lift, overall lift may not be enough to maintain flight and the plane will suddenly drop. Take a look sometime at some of the STOL planes, such as the Pilatus Porter or the Helio Courier/Stallion, and how much of the total wingspan is devoted to flaps. These aircraft can significantly increase total lift over 90% of their wingspan both for takeoff/landing and slow flight. The Courier, for instance has a max gross takeoff weight of over 3600 lbs but can fly at 27 mph (cruise is 140) and land in less than 100 ft. Compare that to a Super Cub, which weighs slightly over 1200 lbs, but stalls(with flaps) at about 35 mph. This is a rough comparison, but you get the idea. (The Courier also has self-deploying leading edge slats, which also improve lift)