To quote Patrick Smith, an airline pilot, blogger, and author of Cockpit Confidential: “You cannot – repeat, cannot – open the doors or emergency hatches of an airplane in flight. You can’t open them for the simple reason that cabin pressure won’t allow it.”
uh...D.B. Cooper!?!?!?!
From Wikipedia (yes, I know the warnings):
During refueling Cooper outlined his flight plan to the cockpit crew: a southeast course toward Mexico City at the minimum airspeed possible without stalling the aircraft (approximately 100 knots (190 km/h; 120 mph)) at a maximum 10,000 foot (3,000 m) altitude. He further specified that the landing gear remain deployed in the takeoff/landing position, the wing flaps be lowered 15 degrees, and the cabin remain unpressurized.
If the pressure is the same inside as outside it is easy to open the door.
DB Cooper exitied a 727 that had rear stairs, which he exited from.
Not the same mechanism as a modern plane, as they dropped down, not in and then out.
Decades ago, old design, re-engineered solution.
D.B. used a ramp on the back that opened hydraulically.
uh...D.B. Cooper!?!?!?!
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The stairs on a 727-100 are outside the (pressurized) “cigar” ,, the door leading to the stairs is not subject to intense negative pressure as it is protected from the airstream by the stairs ,,, with D.B. they were opened with a very low airspeed ,, a speed that would have allowed the hydraulics to operate the stairs.