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Old 01-04-2014, 06:59 PM
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BMatthews
 
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Yep VG, that's what I'm suggesting. And on the tail draggers I've flown those with a more scale like angle at rest do tend to land consistently smoother when wheeled on than tail dragger MODEL designs that tend to sit at a lower angle on the ground.

Mind you keep in mind that when I say "wheeled landings" I'm not talking about pushing the model down and force the touchdown. I'm still doing this from a slow, nose high glide path that produces a nice predictable descent angle. But that angle is already fairly close to the stall angle. So if the model isn't at an attitude where the wheels are already in the 3 point positions then forcing a higher angle just before touchdown is going to stall the model. Which is fine if we can stall it right smack dab at touch down. Otherwise if we flare even a few inches too high and the drag produces a sharp descent the wheels slam to the ground, that kicks the nose up and we get a nice bounce or two.

So I stopped trying with a couple of my models. I just set up the slow but fairly steep glide path and just before touchdown I'll add a click or two of throttle to slow the descent and grease it on. Then I cut the throttle the rest of the way and ease in the up elevator as the model slows down to aid with holding the tail down on our usually bumpy grass field.

With that method my landings on even the most bouncy models look pro. The model hardly jostles until the weight comes onto the mains after the first 10 feet of rollout.

Of course so many other things enter into the picture. The distance of the gear in front of the CG is a major player and might even be considered as THE MAIN factor for the landing behaviour of any model.

I can't say one way or the other what flaps would do for this. My only two flapped models were sailplanes which didn't seem to care one way or the other that the flaps were down as to the angle that the fuselage touched down.

I suspect that the key is that the angle of the wings when in the 3 point attitude still needs to be at or below the stall angle. If it's not then you can't reach the 3 point angle of attack, the plane will stall first. If the angle needed for a 3 pointer is comfortably less than the stall angle then I'd say that you'd likely have a model that can 3 point nice and smooth. If not then it's going to be darn tough to get good bounce free landings.