Should have read further back! John E. In the case I was involved with the blade spar WAS still attached until it fractured roughly mid span after contacting the boom. There were at least three strikes on the fin and two along the boom. If a blade fails, then the remaining blade with all the lift will rise upwards causing a significant bending moment on the mast, pushing the mast backward thus reducing the distance between the blade tip and the fin. The pictures you offered are for a blade in normal flight.