I don't know if this really has to do with security though I'd guess whoever checks out planes missed this one:

Jessica Cabot was born blind, but she'd been on two flights by herself before boarding a United Airlines flight last month, so she figured she knew what to expect. On all three flights, she was told by the flight attendants to remain seated until everyone else was off the plane, and then someone would help her off. That worked the first two times at any rate.

http://consumerist.com/2010/05/unite...-on-plane.html

[moderator: if this is inappropriate for this particular forum please consider putting it where it might be better appropriate - thanks]