MarkHKG From United States of America, joined Dec 2005, 960 posts, RR: 2 Posted (5 years 12 months 2 days 15 hours ago) and read 5308 times:
Here's a question for all you Airbus guys:
Comment on the following statement:
"The A320 family of main cabin doors do not have vent doors to remove residual pressure."
The reason why I have this question is that I can see the vent doors on the B-777 and the E-170 when the door is opened. But my understanding is that the Airbus series doors do not have vent doors, which is why they have the red "CABIN PRESSURE" light that can be seen inside and outside. Therefore, the ability to open the door in a slightly pressurized cabin rests solely on the cockpit getting rid of the pressure, which is in contrast to the B-777 which will vent out the excess pressure with the vent.
Thoughts?
Thanks!
Release your seat-belts and get out! Leave everything!
FlyingColours From United Kingdom, joined Dec 2003, 2315 posts, RR: 11 Reply 1, posted (5 years 12 months 1 day 18 hours ago) and read 5171 times:
As former A320 cabin crew it is my understanding that the doors do not have vents (just like you mentioned) and that any excess cabin pressure will result in a warning light which is clearly visible in our door area, at that point it is on us to call the Flight Supervisor/ Cabin Chief / Purser who will call the flighdeck and the pilots will check the cabin pressure levels and manually open the outflow valve (manually as in set the valve control to manual and then set to full open).
I don't know why the A32X doesn't have a valve like you said however from experiance I can't say I have ever seen one one the 737-300/400/800 or the 757-200 either.
Phil
FlyingColours
Lifes a train racing towards you, now you can either run away or grab a chair & a beer and watch it come - Phil
WNCrew From United States of America, joined Jun 2006, 1322 posts, RR: 9 Reply 2, posted (5 years 12 months 1 day 17 hours ago) and read 5163 times:
Quoting FlyingColours (Reply 1): I can't say I have ever seen one one the 737-300/400/800 or the 757-200 either.
My understanding is that under normal operation any residual pressure in the cabin in a 737/757 is released through outflow valves when the main gear compresses upon intial touchdown and subsequent landing rollout.
ALL views, opinions expressed are mine ONLY and are NOT representative of those shared by Southwest Airlines Co.
Quicker, and IMHO safer and more practical to crack open the cockpit window, if there is residual pressure, it would be due to a problem with the system, opening the window gives me instant inequivable feedback.
Quoting WNCrew (Reply 2): outflow valves when the main gear compresses upon intial touchdown and subsequent landing rollout.
Same on the airbus.
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2enginesonly From Netherlands, joined Jun 2005, 91 posts, RR: 0 Reply 4, posted (5 years 12 months 1 day 16 hours ago) and read 5144 times:
Quoting FlyingColours (Reply 1): I don't know why the A32X doesn't have a valve like you said however from experiance I can't say I have ever seen one one the 737-300/400/800 or the 757-200 either.
As a former 757 tech I can tell you that these vents are absolutely installed on that ship.
These valve are the top and bottom lip of each door which folds inwards when you open the door.....I have no experience with the 737 though however this might change
WNCrew From United States of America, joined Jun 2006, 1322 posts, RR: 9 Reply 5, posted (5 years 12 months 1 day 14 hours ago) and read 5112 times:
Quoting 2enginesonly (Reply 4): As a former 757 tech I can tell you that these vents are absolutely installed on that ship.
These valve are the top and bottom lip of each door which folds inwards when you open the door.....I have no experience with the 737 though however this might change
The 737 operates the same way, but these flaps are not "vents"...they are not there to equalize pressure as they rotate INWARD...not OUTWARD...and they only do so when the door control handle has been moved past a certain point. The reference to the A318-19-20-21 valve (also reffered to as a "flap") is actually just THAT, it allows pressures to equalize between exterior and cabin.
The flaps on the 737-757 only serve as a means to "shrink" the outer surface area of the main doors so they can be opened and closed since the doors themselves are larger than the openings and to OPEN, the doors must first come into the cabin before rotating out.
ALL views, opinions expressed are mine ONLY and are NOT representative of those shared by Southwest Airlines Co.
MarkHKG From United States of America, joined Dec 2005, 960 posts, RR: 2 Reply 6, posted (5 years 12 months 1 day 9 hours ago) and read 5072 times:
Quoting FlyingColours (Reply 1): I don't know why the A32X doesn't have a valve like you said
Thanks for the replies everyone. I'm just curious why Airbus did not opt to install vent flaps into the doors, considering the deaths of at least two cabin crew in two separate incidents involving the A300.
What worries me is that the red "CABIN PRESSURIZED" warning light on the A320/A330/A340 family doors do not activate if the cabin crew are trying to open the door in emergency mode -- i.e. during an evacuation -- which puts them at risk of a sudden opening of the door if the cabin is still pressurized. The warning light only comes on if the door is disarmed.
Release your seat-belts and get out! Leave everything!
JetMech From Australia, joined Mar 2006, 2589 posts, RR: 53 Reply 7, posted (5 years 12 months 1 day 9 hours ago) and read 5068 times:
Quoting WNCrew (Reply 5): The flaps on the 737-757 only serve as a means to "shrink" the outer surface area of the main doors so they can be opened and closed since the doors themselves are larger than the openings and to OPEN, the doors must first come into the cabin before rotating out.
True, but I also think that safety is just as an important reason for the vent flaps. The door handle is mechanically linked to the vent flaps which physically prevents the door handle being moved to the open position if there is a cabin pressure differential. The flaps are rigged to move before the opening mechanism, so that even if someone is strong enough to force the handle when the cabin is pressurised, the vent doors will at least vent some of the pressure differential. These vent doors are also fitted to the cargo doors of many Boeings.
Quoting MarkHKG (Reply 6): Thanks for the replies everyone. I'm just curious why Airbus did not opt to install vent flaps into the doors, considering the deaths of at least two cabin crew in two separate incidents involving the A300.
It does seem to be one of the noticeable differences between Boeings and Airbus. In many critical areas on the 747, Boeing will usually fit some sort of mechanical device to physically prevent something from being activated or moved when it is unsafe to do so. Airbus tends to usually only have some sort of light or buzzer or electrical disconnect to do the same. There does not seem to be as many mechanical interlocks on an Airbus, which then puts the onus back on the individual to be sufficiently trained to recognise these warnings.
Regards, JetMech
JetMech split the back of his pants. He can feel the wind in his hair.