sentences:  Hooe taped down his trouser cuffs, donned a parachute, and rigged a lifeline to service the engines from the makeshift catwalks, but the inflight lubricating systems only delayed and could not prevent engine wear.Once the cylinders began missing, the "Question Mark" shortened its loops to remain within gliding distance of Van Nuys.Eaker was able to clear fouled spark plugs by completely opening the throttles.