Delta is letting employees offer customers nearly $10,000 in compensation to give up seats on overbooked flights, hoping to avoid an uproar like the one that erupted at United after a passenger was dragged off a jet.United is taking steps too. It will require employees seeking a seat on a plane to book it at least an hour before departure, a policy that might have prevented last Sunday's confrontation.Those and other changes show airlines are scrambling to respond to a public-relations nightmare — the video showing airport officers violently yanking and dragging 69-year-old David Dao from his seat on a sold-out United Express flight.Dao and three others were ordered off the plane after four airline employees showed up at the last minute and demanded seats so they could be in place to operate a flight the next day in Louisville, Kentucky.On Friday, a United spokeswoman said the airline changed its policy to require traveling employees to book a flight at least 60 minutes before departure. Had the rule been in place last Sunday, United Express Flight 3411 still would have been overbooked by four seats, but United employees could have dealt with the situation in the gate area instead of on the plane.Delta Air Lines is moving to make it easier to find customers willing to give up their seats.