The problem, if I can describe it clearly, is that a standard paddle style holster has a hole punched in it so that the padlock hasp should pass between the rear of the trigger and the trigger guard. When done properly, the gun cannot be withdrawn from the holster, as the hasp of the padlock won't let the trigger pass.
If the gun is partially out of the holster when the padlock is applied, then the hasp of the padlock is between the front of the trigger and the trigger guard. In this position, the flap of the holster at the rear of the slide cannot be snapped. So you push in the weapon to fully seat it into the holster, and the hasp of the padlock presses the Glock's trigger safety, and presses the trigger.
If a weapon such as the M1911, with a frame mounted safety, were used, then if the manual safety were applied then the same scenario would just result in the trigger not moving, and the weapon not fully seating into the holster. If the manual safety were not engaged, the weapon would still discharge when pressed into the holster.
If the TSA insists on this silly locking crap, then they need to provide a small lockbox for the weapon.
Thanks for the info. I’m clear now. I agree, a lock box in the cockpit would be best.
Accidental Discharge by airline pilot = Glock. Plaxico = Glock. Federal Agent in front of school children = Glock. One of my friends had an accidental discharge with a Glock. I won’t own a Glock. Flame away....