Regarding “tip walking” which is a yaw PIO, here’s a few additional comments.
Drag tip drag rudder steered rigid wings are the most prone to a tip walking PIO, despite plenty of sweep and dihedral. I think more so than any other tailless wing. But like other yaw PIOs you can learn to avoid or minimize them.. It’s just that some wings are so stable you can’t even introduce a yaw PIO, and others are very prone.
Regarding “tip steering” of a tip drag rudder tailless wing, like a Fledge you can see how a 100% is a PIO…the wing is plenty stable.
When towing a wing (pilot attached) the shifting side-to-side creates an adverse yaw force, and towing can cause many new pilots to get into a yaw PIO. The wing’s inherent stability (plenty in free flight) is insufficient in a situation where the adverse yaw induced by tow-line force, can start a yaw PIO. This is the biggest challenge for new tow pilots.
Note that trikes are similar, but normally not enough to precipitate a yaw PIO, but the asymmetrical thrust exerts enough adverse yaw to slightly inhibit roll inputs. In towing and triking…when you shift one way to roll, the thrust/tow force is trying to yaw the wing in the opposite direction. It matters only a little in triking…but a lot in towing.
Comments
Regarding “tip walking” which is a yaw PIO, here’s a few additional comments.
Drag tip drag rudder steered rigid wings are the most prone to a tip walking PIO, despite plenty of sweep and dihedral. I think more so than any other tailless wing. But like other yaw PIOs you can learn to avoid or minimize them.. It’s just that some wings are so stable you can’t even introduce a yaw PIO, and others are very prone.
Regarding “tip steering” of a tip drag rudder tailless wing, like a Fledge you can see how a 100% is a PIO…the wing is plenty stable.
When towing a wing (pilot attached) the shifting side-to-side creates an adverse yaw force, and towing can cause many new pilots to get into a yaw PIO. The wing’s inherent stability (plenty in free flight) is insufficient in a situation where the adverse yaw induced by tow-line force, can start a yaw PIO. This is the biggest challenge for new tow pilots.
Note that trikes are similar, but normally not enough to precipitate a yaw PIO, but the asymmetrical thrust exerts enough adverse yaw to slightly inhibit roll inputs. In towing and triking…when you shift one way to roll, the thrust/tow force is trying to yaw the wing in the opposite direction. It matters only a little in triking…but a lot in towing.