Flying_Corporal
New Member
What happens if the cabin becomes overpressurized?
Overpressurization??
- Thread starter Flying_Corporal
- Start date
mtsu_av8er
Well-Known Member
The cabin will burst, and all is lost!!!!!
That shouldn't happen, though, because there is at least one pressure relief valce that should open if the cabin pressure exceeds limits.
That shouldn't happen, though, because there is at least one pressure relief valce that should open if the cabin pressure exceeds limits.
Pickle
grumpy puppy
The 757 has positive relief valves that should open if for some reason the outflow valve does not open. The 757 has two AUTO controllers, and also has a MANUAL mode. Interestingly enough, I decided to dig through the CFM and there really is no guidance in either the CFM or the QRH for an overpressure situation. I can find no EICAS messages that deal with it, with the exception of " <font color="yellow">CABIN AUTOMATIC INOPERATIVE</font>" , which means that the Auto 1 and Auto 2 cabin altitude control functions are inoperative or the cabin altitude selector is in manual. Can any other 757/767 people find it in their books?
sorrygottarunway
Well-Known Member
the 172 I fly is always overpressurized, with all the hot air coming out of my instructor's mouth.
kostcoguy
New Member
[ QUOTE ]
the 172 I fly is always overpressurized, with all the hot air coming out of my instructor's mouth.
[/ QUOTE ]
lol.
I looked for a little, I couldn't find anything on the valves, it might not have to do with anything special, just valves located somewhere, where if too much pressure builds up, it blows them open, and then a light goes on in the cockpit notifying the pilots of it. Just a guess though.
the 172 I fly is always overpressurized, with all the hot air coming out of my instructor's mouth.
[/ QUOTE ]
lol.
I looked for a little, I couldn't find anything on the valves, it might not have to do with anything special, just valves located somewhere, where if too much pressure builds up, it blows them open, and then a light goes on in the cockpit notifying the pilots of it. Just a guess though.
mtsu_av8er
Well-Known Member
[ QUOTE ]
I looked for a little, I couldn't find anything on the valves, it might not have to do with anything special, just valves located somewhere, where if too much pressure builds up, it blows them open, and then a light goes on in the cockpit notifying the pilots of it. Just a guess though.
[/ QUOTE ]
This talks about it a little bit...
737 System
I looked for a little, I couldn't find anything on the valves, it might not have to do with anything special, just valves located somewhere, where if too much pressure builds up, it blows them open, and then a light goes on in the cockpit notifying the pilots of it. Just a guess though.
[/ QUOTE ]
This talks about it a little bit...
737 System
mtsu_av8er
Well-Known Member
I think he was referencing the statement about the Learjet being bulletproof....
I'm looking at the checklist for a LR-55 and it says:
1. Pressurization AUTO-MAN Switch--MAN (switch to manual instead of automatic)
2. UP-DN Manual Control--UP as required (to get a higher cabin altitude by manually opening the outflow valve)
3. One BLEED AIR Switch--OFF
4. Adjust power on the opposite engine to control pressurization. (less power, less bleed air, less pressurizaton)
1. Pressurization AUTO-MAN Switch--MAN (switch to manual instead of automatic)
2. UP-DN Manual Control--UP as required (to get a higher cabin altitude by manually opening the outflow valve)
3. One BLEED AIR Switch--OFF
4. Adjust power on the opposite engine to control pressurization. (less power, less bleed air, less pressurizaton)
Mr_Creepy
Well-Known Member
This outspoken guy in our Midway ground school claimed that dry ice was responsible for the Payne Stewart crash. We all laughed at him.
Imagine my chagrin when I found out from some of the investigators here in Orlando that there were two large coolers of dry ice on the plane (they were going fishing.)
It is possible, they said, that they never lost pressurization, but just ran out of oxygen and passed out.
I said "But I thought the chase fighters saw the windows iced up?" Their reply, "Since the Lear 35 operators normally climb in IAS mode, they did not main a steady altitude and it is possible that the altitude oscillations they experienced (between 35,000 and 53,000 ft) could have caused water vapor to freeze on the inside of the windows. This normally happens at altitude anyway."
My reply was "Huh!" I learned something that day.
Imagine my chagrin when I found out from some of the investigators here in Orlando that there were two large coolers of dry ice on the plane (they were going fishing.)
It is possible, they said, that they never lost pressurization, but just ran out of oxygen and passed out.
I said "But I thought the chase fighters saw the windows iced up?" Their reply, "Since the Lear 35 operators normally climb in IAS mode, they did not main a steady altitude and it is possible that the altitude oscillations they experienced (between 35,000 and 53,000 ft) could have caused water vapor to freeze on the inside of the windows. This normally happens at altitude anyway."
My reply was "Huh!" I learned something that day.
ready2fly
Well-Known Member
[ QUOTE ]
This outspoken guy in our Midway ground school claimed that dry ice was responsible for the Payne Stewart crash. We all laughed at him.
Imagine my chagrin when I found out from some of the investigators here in Orlando that there were two large coolers of dry ice on the plane (they were going fishing.)
It is possible, they said, that they never lost pressurization, but just ran out of oxygen and passed out.
[/ QUOTE ]
So far as my knowledge of the case from sitting in the office next to the attorneys who were working on the case and being privy to seeing some of the research..... that outspoken guy was wrong.
It "could have" been a factor - but wasn't.
This outspoken guy in our Midway ground school claimed that dry ice was responsible for the Payne Stewart crash. We all laughed at him.
Imagine my chagrin when I found out from some of the investigators here in Orlando that there were two large coolers of dry ice on the plane (they were going fishing.)
It is possible, they said, that they never lost pressurization, but just ran out of oxygen and passed out.
[/ QUOTE ]
So far as my knowledge of the case from sitting in the office next to the attorneys who were working on the case and being privy to seeing some of the research..... that outspoken guy was wrong.
It "could have" been a factor - but wasn't.
Hi...
As indicated in the NTSB final report, (and by R2F), there was no dry ice on board this aircraft. Quite a few interesting details discovered during the investigation, however. Here's a link if you're interested.
Regards
NTSB Accident Publication
As indicated in the NTSB final report, (and by R2F), there was no dry ice on board this aircraft. Quite a few interesting details discovered during the investigation, however. Here's a link if you're interested.
Regards
NTSB Accident Publication