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I've never seen a 727's aft stairs open, but presumably, based on an Wikipedia image and common sense, they do reach the ground when the aircraft is on the ground. Furthermore, (as I understand it), airliners land with a positive pitch, which means that assuming a level runway, the rear of the aircraft will touch down first. However, this suggests that if the aft stairs of the 727 were open during landing, they would impact the ground during landing and, given the pitch, do more than scrape the ground and cause damage to the aircraft.

However, DB Cooper's jump left the aft stairs open, and (as far as I can tell) it seems that the landing was uneventful besides the stress of having a hijacker potentially on board (although it's quite understandable if no one made any record of it, given there were slightly more important things to deal with).

If DB Cooper's flight did land without damage, why is that—did the 727's aft stairs not fully touch the ground? If the stairs did impact the ground, was there sufficient damage to require repairs?

(I meant this question to be more about the 727 than DB Cooper, but since his was the only landing with stairs open, there wasn't much room for speaking in general terms).

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I do not think they landed with the airstairs down: The airstairs are powered to get them back up since they are heavy, and this feature can be operated from inside the aircraft as well.

The following answer is of Yahoo answers and while I can't confirm is accuracy, it sounds very plausible:

There are 2 control handles for the airstairs on a B727, one under a panel on the lower fuselage right beside the stair forward hinge point, and one at the top of the stairs behind a panel on the left side which can only be accessed when the rear cabin door is open. Because the cabin door can only be opened when the aircraft is unpressurized, this usually would prevent its actuation in flight. However, after the D B Cooper hijacking a device was added referred to as an anti-hijack vane that would swing over when the aircraft was in flight and prevent the door opening. To close the door either an electric hydraulic pump has to be turned on in the cockpit, or a hand pump beside the lower control operated while either handle is held to the close position. The door will free fall open without hydraulic pressure, but the support arms may have to be pushed to an overcenter position.


Assuming that the air stairs were deployed, it may be that the force of the airflow passing by would have been sufficient to spare the stairs from a tailstrike. The stairs have a large surface area and moving at perhaps around 100 knots when the nosewheel touches down would still generate a considerable force to push them into the fuselage.

The term deployed may also suggest that the airstairs may have been damaged and uable to retract the whole way, leaving it halfway stuck but still out of tailstrike range.

The aircraft was empty at the time which would have helped in either situation.

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