Probably people confusing what should be on the apron - a ramp (a movable staircase that passengers use to board or leave an aircraft) - and an apron can also be n 1: a garment of cloth or leather or plastic that is tied about the waist and worn to protect your clothing 2: (golf) the part of the fairway leading onto the green 3: the part of a modern theater stage between the curtain and the orchestra (i.e., in front of the curtain) [syn: proscenium, forestage] and of course 4: a paved surface where aircraft stand while not being used!
Practise autorotation go!
