trimming for glide

I don't seem to have the coordination to throw something flat and level, so
my attempts at glide testing have always had problems.
has anyone tried making a gadget that could launch a plane enough to do
glide tests? I was thinking like a high start but then realized that if
something didn't work well I'd have a long length of tubing dragging my
creation along the ground doing its best to re-kit said plane.
I ask this in regard to a rocket boosted glider, but have realized in my
experience that my inability shows in other areas, and If I want to build a
frankenfoamy like bird, I am going to need to do some testing.
Reply to
tater schuld
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Practice with a cheap chuck glider. You need to aim it straight at the horizon (slightly down, actually, but experience suggests that if you aim at the horizon the model will usually end up pointing slightly below the horizon anyway) and give it just enough shove to fly out of your hand. The secret is having it in its best gliding attitude at its best gliding speed as it leaves your hand. This *is* a test glide, after all. Hold it just as near to the CofG as you can too, and obviously wings level.
The technique is good for any hand-launched model - glider or power - although obviously heavier models will need a rather firmer launch than gossamer-weight floaters ..... and low-wingers are notoriously difficult to hand launch because the wing is right in the way of where you want to hold!
Don't take a huge run-up before launching - all it does is make you breathless and sweaty. Watch almost anyone do this and you will see that they practically stop running before they actually launch the model anyway. So don't do it. Two or three steps is more than enough as most of the launch is done by the arm swing. Don't try and launch the model too hard though, it's a model, not an olympic javelin. If you try too hard you can't control your technique and the results are, at their cheapest, disappointing.
Steve
Reply to
Steve
I've never made such a device, but what comes to mind is a speargun, or crossbow type arrangement. PVC and surgical tubing?
have fun :)
Reply to
Steve Banks
Two options:
1.) Perfect your launch technique. Unless you have serious physical limitations, you CAN learn to chuck gliders. I'm the world's second-biggest klutz, and I learned.
2.) Look into "pedal launchers."
Reply to
mkirsch1
Trim is speed-sensitive, by definition. If the trim is unchanged, and the airplane is travelling faster than the desired glide speed, it will pull its nose up, and of course the nose will drop if the speed is too low. Launch attitude is critical, but so is the release speed. Dan
Reply to
Dan_Thomas_nospam
| I don't seem to have the coordination to throw something flat and | level, so my attempts at glide testing have always had problems.
Sure you do. As suggested, try it with a cheap free-flight plane. The $3 foam planes at Wal Mart ought to be fine. | has anyone tried making a gadget that could launch a plane enough to do | glide tests?
If you're using a gadget, it's not really a proper glide test :)
| I was thinking like a high start but then realized that if | something didn't work well I'd have a long length of tubing dragging my | creation along the ground doing its best to re-kit said plane.
Well, a high start is pretty much the logical conclusion of what you're talking about ...
| I ask this in regard to a rocket boosted glider, but have realized in my | experience that my inability shows in other areas, and If I want to build a | frankenfoamy like bird, I am going to need to do some testing.
If you just need more flight time, stand at the top of a hill and throw it straight ahead -- and it doesn't have to be a hard throw. Preferably into the wind. If the wind is strong enough, you're slope soaring, and if your plane is properly trimmed and all, you can keep it up for a long time. (And of course, some of us love to fly like this.)
Reply to
Doug McLaren
Depends on what you're trying to do. If you're only trying to test the glide of the rockt-boosted glider, try aiming the plane at the ground 50 feet in front of you and give it a solid toss. With the nose of the plane pointed at the spot you are trying to hit, the glider will get there with a 10-1 glide ratio. Trying to toss flat and level is much harder than pointing the nose down. Use the elevator to level out the plane and flatten the glide once the plane is safely in the air.
-Fritz
Reply to
Fritz Bien

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