Saturday, July 26, 2008

Disarming Crew,Unarmed Door

Frequent fliers (or even infrequent fliers) will recall the monotonous announcement from the flight deck of commercial flights " cabin crew to arm all doors, cross check and report".This is the first small step of the multi-step departure procedure.Passengers heave a sigh of relief at each of these steps. Even after arming the door the aircraft, a departure could take a long while - congestion in Indian skies and runways being what it is.

However, with Shri Sharad Pawar being on board Jet Airways flight 9W 362,ATC may have given early clearance to this aircraft.The crew must have closed the door with alacrity to enable early takeoff. However,either the door was not armed (closed) properly or door was closed but not aligned correctly.In addition,the crossing-checking was perhaps not done or not done in the prescribed manner.

At about 5,000 feet the crew, fortunately, noticed that the door was not closed properly and the plane,thankfully, made a safe emergency landing.

So, what happens if the cabin door opens mid-flight? Apparently, this is not possible:
"In practice, however, it's due to the large pressure difference between the pressurized fuselage and the outside air, that the doors would be un-openable. As has already been stated, emergency doors/windows almost always open inwards, and main "cabin" doors need to initially open inwards before they can be rotated outward. The large pressure differential present, however, creates an outward acting force on the doors of such magnitude that even a very strong person, or even several would be incapable of pulling inward sufficiently to overcome it and allow the door to open, even if they rotate the door handle.

This aircaft plunged 20,000 feet on account of this hole,caused midflight, in fuselage

In other words, the doors are not only larger than the door opening, but they are also forced and sealed shut by an outward pressure caused by the pressurized cabin."
(Read the full article)

However, despite all safety measures, the door of an aircraft can still fall of mid-flight.Just click here to read when this happened to this American Eagle commuter plane (ATR-72)in 1995.

So, even if you are the type who does not follow cabin crew instructions,just ensure that have have your seat belt on,always.Just in case..

Emergency landing by Jet Airways.Door not closed correctly.

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