Can the cabin door be opened in flight?
Jul 4, 2002 | 4:45 am
#16
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You cannot de-pressurize an aircraft below the outside pressure for a departure. There is no mechanism for sucking air out of the cabin. The only thing you can do is blow air into the cabin and let air leave the cabin on its own.
The cabin air pressure depends on the rate at which air is being pushed into the cabin and the rate at which air is allowed to leave the cabin through the outflow valves. More air coming in than going out means increasing air pressure, and less air coming in than going out means decreasing air pressure.
I believe you could have lower cabin pressure than outside pressure when landing, if you close the outflow valves when descending. It shouldn't be a big difference -- maybe 0.25 psi.
I suspect that if pressurization begins before take-off, the pressure differential is very small. Maybe it has something to do with conserving engine power during take-off.
About a year or so ago, an AA (A300?) landed at MIA. The FA opened the door too soon, and the plane suddenly depressurized. He was thrown out of the plane onto the ground, and I think he was killed.
[This message has been edited by JS (edited 07-04-2002).]
The cabin air pressure depends on the rate at which air is being pushed into the cabin and the rate at which air is allowed to leave the cabin through the outflow valves. More air coming in than going out means increasing air pressure, and less air coming in than going out means decreasing air pressure.
I believe you could have lower cabin pressure than outside pressure when landing, if you close the outflow valves when descending. It shouldn't be a big difference -- maybe 0.25 psi.
I suspect that if pressurization begins before take-off, the pressure differential is very small. Maybe it has something to do with conserving engine power during take-off.
About a year or so ago, an AA (A300?) landed at MIA. The FA opened the door too soon, and the plane suddenly depressurized. He was thrown out of the plane onto the ground, and I think he was killed.
[This message has been edited by JS (edited 07-04-2002).]
Jul 4, 2002 | 2:25 pm
#17
Join Date: May 2002
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Copied from this link:
http://news.airwise.com/stories/2000/03/952626592.html
Jet's Door Opened At 12000 Feet
Mar 9, 2000
A flight engineer opened a door to pull in a loose strap on board an American Airlines jet flying at 12,000 feet. Passengers on the Miami to New York, Newark flight did not know what was happening until there was a sudden change in cabin pressure.
They felt their ears pop and air rushed through the cabin about 1.30 p.m. Wednesday when a rear door was opened
The pilot later explained that the strap had to be retrieved because of the possibility its buckle could break loose and get sucked into an engine, passenger Cora Diaz told The Star-Ledger of Newark in a story for today's editions.
Diaz said she was sitting at the back of the airplane and saw a flight engineer and two crew members open the door.
``Everybody picked up their heads and said, 'What's going on? What's going on?''' Diaz said.
After closing and locking the door seconds later, the flight engineer returned to the cockpit and the pilot explained the procedure. The pilot said the strap was inadvertently left behind by food service workers.
He told passengers he slowed the plane and remained at 12,000 feet during the maneuver, Diaz said.
The Federal Aviation Administration is reviewing the incident, and a spokesman declined to say whether the pilot had acted properly.
http://news.airwise.com/stories/2000/03/952626592.html
Jet's Door Opened At 12000 Feet
Mar 9, 2000
A flight engineer opened a door to pull in a loose strap on board an American Airlines jet flying at 12,000 feet. Passengers on the Miami to New York, Newark flight did not know what was happening until there was a sudden change in cabin pressure.
They felt their ears pop and air rushed through the cabin about 1.30 p.m. Wednesday when a rear door was opened
The pilot later explained that the strap had to be retrieved because of the possibility its buckle could break loose and get sucked into an engine, passenger Cora Diaz told The Star-Ledger of Newark in a story for today's editions.
Diaz said she was sitting at the back of the airplane and saw a flight engineer and two crew members open the door.
``Everybody picked up their heads and said, 'What's going on? What's going on?''' Diaz said.
After closing and locking the door seconds later, the flight engineer returned to the cockpit and the pilot explained the procedure. The pilot said the strap was inadvertently left behind by food service workers.
He told passengers he slowed the plane and remained at 12,000 feet during the maneuver, Diaz said.
The Federal Aviation Administration is reviewing the incident, and a spokesman declined to say whether the pilot had acted properly.
Jul 5, 2002 | 10:00 am
#18
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<font face="Verdana, Arial, Helvetica, sans-serif" size="2">Originally posted by cnk:
So during taxi, this would mean that they depressurize the interior to equate to a higher altitude</font>
So during taxi, this would mean that they depressurize the interior to equate to a higher altitude</font>
Jul 5, 2002 | 10:03 am
#19
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<font face="Verdana, Arial, Helvetica, sans-serif" size="2">Originally posted by Comicwoman:
Yes, but D.B. Cooper opened the door in the tail of an airplane.(I am sure someone here can cite the mfg and model</font>
Yes, but D.B. Cooper opened the door in the tail of an airplane.(I am sure someone here can cite the mfg and model</font>
D.B. Cooper had the crew descend to an appropriate altitude and then depressurize the airplane. Also, the rear stairs on a B727 is not a plug-type door so that wouldn't have been an issue.