Unwanted snap?
06-10-2002 | 04:35 AM
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Unwanted snap?
snap-rolling out of a loop is usually a tip-stall situation. 2 basic causes:
1)You apply excessive elevator and stall the wing, even at high speeds. (probably not this case)
2)You lose too much speed before going over the top.
If you've got enough power for the weight of the plane... try a longer, lower pitch prop. This will reduce the loss of speed.
the problem can be agrivated by having the plane set up with cross correction of rudder and aileron. Go to www.nsrca.org for the correct way to ensure a plane is trimmed.
1)You apply excessive elevator and stall the wing, even at high speeds. (probably not this case)
2)You lose too much speed before going over the top.
If you've got enough power for the weight of the plane... try a longer, lower pitch prop. This will reduce the loss of speed.
the problem can be agrivated by having the plane set up with cross correction of rudder and aileron. Go to www.nsrca.org for the correct way to ensure a plane is trimmed.
06-10-2002 | 08:39 AM
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Unwanted snap?
Just thought of another thing that might help...
1 to 2 turns on the aileron clevices to "reflex" them upward, giving a touch of a wash-out effect. This makes the tips stall a little later.
1 to 2 turns on the aileron clevices to "reflex" them upward, giving a touch of a wash-out effect. This makes the tips stall a little later.
07-25-2002 | 01:03 PM
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Unwanted snap?
Yes, the ailerons being deflected down, even imperceptibly to the naked eye, can cause some large effects on performance.
A member at our field had a GP C-182 ARF that had a bad snap and ballooning problem. 2 turns on each aileron clevice, which didn't visibly move the ailerons, completely cured it.
Not the same plane... but the same problems...
On dual aileron servo aircraft... I will sometmes set up the ailerons as flaperons. and dial in the correct neutral, then adjust the clevices for that positioning using the Y-cable. Pin the ailerons in position with the TX and RX on. disconnect the clevices, change to the Y... adjust servo centers and clevices without moving the ailerons.
(I always try to reset back to 100% throw and 0 trim center on the TX, using mechanical adjustments.)
A member at our field had a GP C-182 ARF that had a bad snap and ballooning problem. 2 turns on each aileron clevice, which didn't visibly move the ailerons, completely cured it.
Not the same plane... but the same problems...On dual aileron servo aircraft... I will sometmes set up the ailerons as flaperons. and dial in the correct neutral, then adjust the clevices for that positioning using the Y-cable. Pin the ailerons in position with the TX and RX on. disconnect the clevices, change to the Y... adjust servo centers and clevices without moving the ailerons.
(I always try to reset back to 100% throw and 0 trim center on the TX, using mechanical adjustments.)
11-22-2002 | 08:14 AM
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From: Cartersville, GA
unwanted snap
Check the CG, it may be a little tail heavy.
You wont the ailerons slightly up for a wash-out effect, slighty down will cause tip stall, snap.
Down thrust will help the trim chang from full power to glide. With down thrust the elivator trim must be up, to hold the nose up at high power, so when you bring the power back for landing you have the up trim for glid trim.
Jerry
You wont the ailerons slightly up for a wash-out effect, slighty down will cause tip stall, snap.
Down thrust will help the trim chang from full power to glide. With down thrust the elivator trim must be up, to hold the nose up at high power, so when you bring the power back for landing you have the up trim for glid trim.
Jerry
