Practical tips-- putting "effective dihedral" to work in flight

This page was last updated June 18, 2014.

The odds of this ever happening to you are probably less than one in a million, but if you ever manage to snag a draggy object on a wingtip or side wire, do not attempt to pull in for control. As you decrease your glider's angle-of-attack, the "effective dihedral" will become strongly negative, and the glider will generate a powerful "upwind" roll torque-- away from the draggy object. Let the bar be close to trim, where the "effective dihedral" is closer to neutral.

If you continue to have roll control problems, move the bar further forward if the draggy wing is tending to rise, and move the bar further aft if the draggy wing is tending to drop.

A mental shortcut-- the bar controls the "good" or non-draggy wing wing. Moving the bar aft lowers the "good" wing, and moving the bar forward raises the "good" wing.

A pilot flying with a large, draggy camera installation mounted on one wing may notice a similar effect-- a pronounced tendency for the glider to roll away from camera at low angles-of-attack / high airspeeds. The cure for this problem is to slow down toward trim, not to pull in the bar for "more control".

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