Go Back  PPRuNe Forums > Flight Deck Forums > Rumours & News
Reload this Page >

Lufthansa 737 Pressurisation Problem

Rumours & News Reporting Points that may affect our jobs or lives as professional pilots. Also, items that may be of interest to professional pilots.

Lufthansa 737 Pressurisation Problem

Old 19th Oct 2010, 17:10
  #1 (permalink)  
Thread Starter
 
Join Date: Oct 1999
Location: England
Posts: 123
Received 0 Likes on 0 Posts
Lufthansa 737 Pressurisation Problem

Accident: Lufthansa B735 near Leipzig on Oct 19th 2010, cabin pressure problems injure 5
By Simon Hradecky, created Tuesday, Oct 19th 2010 16:03Z, last updated Tuesday, Oct 19th 2010 16:03Z

The Aviation Herald

A Lufthansa Boeing 737-500, registration D-ABIR performing flight LH-1104 from Frankfurt/Main to Leipzig (Germany) with 70 passengers and 5 crew, was enroute at FL230 when cabin pressure problems occurred, the oxygen masks were not released. The crew requested priority for the approach and landing in Leipzig and landed safely 36 minutes after departure from Frankfurt. 5 passengers needed to be taken to hospitals with circulatory problems and ear pain.

Lufthansa said, there had been cabin pressure irregularities during the flight, the passenger oxygen masks were not released. 5 passengers were taken to hospitals for treatment of circulatory problems and ear pain. The cause of the irregularity is not yet known.
John Boeman is offline  
Old 19th Oct 2010, 20:50
  #2 (permalink)  
 
Join Date: Apr 2002
Location: FUBAR
Posts: 3,348
Likes: 0
Received 0 Likes on 0 Posts
Leaky old birds, with a capricious cabin pressure controller to boot, the classics. Always surprised to see Luftie , or indeed any "legacy" carrier, still operating them.
They are getting on a bit , and the pressurisation system was hardly glitchproof when new, 20 years later, as I am finding out again, it is pretty naf
captplaystation is offline  
Old 20th Oct 2010, 09:17
  #3 (permalink)  
 
Join Date: Mar 2001
Location: I wouldn't know.
Posts: 4,497
Likes: 0
Received 0 Likes on 0 Posts
It is believed that the boeing fleet will be replaced by the Bombardier C-Series.

By the way, classic does not necessarily mean old and bad pressurization controllers, ours (300 and 500s) all had the same digital pressurization system we now have in the NG.
Denti is offline  
Old 20th Oct 2010, 09:40
  #4 (permalink)  
 
Join Date: Apr 2002
Location: FUBAR
Posts: 3,348
Likes: 0
Received 0 Likes on 0 Posts
True indeed, but in spite of this they seem to play up a bit more, and of course they are working hard to contain the effects of a leaky old airframe too.
captplaystation is offline  
Old 20th Oct 2010, 13:20
  #5 (permalink)  
 
Join Date: Aug 2010
Location: Mad Now
Age: 43
Posts: 32
Likes: 0
Received 0 Likes on 0 Posts
So, what to do then?

Ok then, sorry to put my 0.02$ as an SLF between, but what can one do if such situation happens on the flight? Is there some remedy that can be applied by a PAX when no masks are available? Breath deeply, stop breathing at all, etc? I understand that the masks alone don't help for the pain in the ears, but in general, what could be done? And just out of my interest, why isn't there a manual release button for the masks to drop out?

Cheers
RS
RockShock is offline  
Old 20th Oct 2010, 13:29
  #6 (permalink)  
Per Ardua ad Astraeus
 
Join Date: Mar 2000
Location: UK
Posts: 18,579
Likes: 0
Received 0 Likes on 0 Posts
A bit of a guess here, RS, but it may be that the crew noticed a problem with the cabin pressure and made an emergency descent (which can cause an element of distress and sometimes ear problems). In doing so they may well have kept the cabin pressure sufficiently high so as not to require oxygen mask deployment? There is indeed a manual mask deployment facility in the cockpit. In short I suspect that there was in fact no need for the masks.
BOAC is offline  
Old 20th Oct 2010, 18:15
  #7 (permalink)  
 
Join Date: May 2010
Location: Austria
Age: 47
Posts: 80
Likes: 0
Received 1 Like on 1 Post
Okay, if they were in FL230, than they will get down pretty quick. Up to FL250 there is no need for a Pax drop down system at all.
Our Q400 for example flies 25000 without...
8314 is offline  
Old 20th Oct 2010, 20:21
  #8 (permalink)  
 
Join Date: Sep 2008
Location: Ottawa, Canada
Posts: 27
Likes: 0
Received 0 Likes on 0 Posts
What to do

If the masks don't drop it's going to be because there is no need for supplemental oxygen. The only thing remaining is dealing with the sudden pressure changes on the body.

I'm SLF but from my scuba diving training you want to keep breathing to keep the pressure in your lungs equal to that on your body - holding your breath can damage your lungs when scuba diving and whilst aircraft have less pressure range I assume the same things will apply. Just try clearing the ears normally remembering that you will have an initial decrease and then an increase in pressure.
notfred is offline  
Old 21st Oct 2010, 10:09
  #9 (permalink)  
 
Join Date: May 2005
Location: Out of a suitcase
Posts: 156
Received 0 Likes on 0 Posts
of course they are working hard to contain the effects of a leaky old airframe too.

Cobblers !!

The Classic aircraft are subject to leak rate checks as laid down in the AMM on a fairly regular basis, they are no worse (or better) than the NG variant,
mccdatabase is offline  
Old 21st Oct 2010, 10:43
  #10 (permalink)  
Per Ardua ad Astraeus
 
Join Date: Mar 2000
Location: UK
Posts: 18,579
Likes: 0
Received 0 Likes on 0 Posts
Your cobblers and I raise you twaddle. I used to fly a 300 that was incapable of pressurising from take-off single pack 'cos it leaked so much. Theory and practice, eh?
BOAC is offline  
Old 21st Oct 2010, 10:57
  #11 (permalink)  
 
Join Date: Jul 2000
Location: My views - Not my employer!
Posts: 1,031
Likes: 0
Received 0 Likes on 0 Posts
I flew a -400 back from BOD which didn't pressurise on a single pack.

Once they changed the old gummed up fwd outflow valve it did...
Cough is offline  
Old 21st Oct 2010, 13:13
  #12 (permalink)  
 
Join Date: May 2005
Location: Out of a suitcase
Posts: 156
Received 0 Likes on 0 Posts
I used to fly a 300 that was incapable of pressurising from take-off single pack 'cos it leaked so much
See your twaddle and raise you a balderdash !

One badly maintained aircraft does not mean that the type is in someway deficient, we have an ageing 300 fleet any of which that can happily operate on one pack if the necessity arises albeit at a reduced altitude of FL250.,

I call that putting the theory into practice.
mccdatabase is offline  
Old 21st Oct 2010, 13:47
  #13 (permalink)  
 
Join Date: Feb 2006
Location: On the big blue planet
Posts: 1,027
Received 24 Likes on 12 Posts
holding your breath can damage your lungs
But only during ascend, not in a descent!

skadi
skadi is offline  
Old 21st Oct 2010, 15:26
  #14 (permalink)  
 
Join Date: Sep 2010
Location: reading uk
Age: 77
Posts: 98
Likes: 0
Received 0 Likes on 0 Posts
8314

I`ll make a point of not flying with you then.

Dave
arearadar is offline  
Old 22nd Oct 2010, 19:35
  #15 (permalink)  
 
Join Date: Aug 2009
Location: Germany
Posts: 72
Likes: 0
Received 0 Likes on 0 Posts
Quote:
holding your breath can damage your lungs
But only during ascend, not in a descent!

skadi
Loss of pressurization is a rapid ascend inside the previous pressurized cabin.
TheWanderer is offline  
Old 22nd Oct 2010, 19:49
  #16 (permalink)  
 
Join Date: Aug 2009
Location: Germany
Posts: 72
Likes: 0
Received 0 Likes on 0 Posts
FRA - LEJ is about 150NM great circle distance, so they were not cruising at a high level.

@RockShock:

Breath normally and stay calm, keep your seat belt fastened at all times when on your seat.

If masks do not drop, there is no need for masks.
Masks drop automatically at about 14.000 ft cabin altitude or at any time when manually deployed by the pilot. The pilot has a manual deploy switch in the cockpit.
When deployed, masks need to be activated by the passenger by pulling them down to you.
Once activated, oxygen will be produced from a chemical reaction and mixed with normal cabin air while breathing through your mask.

The chemical reaction produces heat and there might be a burning or electrical smell that origins from the chemical reaction and is normal.

There is one oxygen generator supplying oxygen to all masks for one row of seats.

Oxygen supply is available for about 20 minutes and cannot be stopped once it is activated due to the nature of the chemical reaction.
TheWanderer is offline  
Old 23rd Oct 2010, 11:35
  #17 (permalink)  
 
Join Date: Mar 2007
Location: FL370
Posts: 4
Likes: 0
Received 0 Likes on 0 Posts
Thumbs up!

Can't exaplaine better than this..
sooperdede is offline  
Old 24th Oct 2010, 16:26
  #18 (permalink)  
 
Join Date: Aug 2010
Location: Mad Now
Age: 43
Posts: 32
Likes: 0
Received 0 Likes on 0 Posts
Thanks for explanation

Most informative TheWanderer, thanks! My only concern was that the pasengers of the flight were taken to the hospital with ear pains etc, but indeed this things couldn't be prevented with the oxygen masks and were simply the result of the depressurization of the environment they were in. This still makes me wonder, though, what to do in case the pressure drops fast to make the pressures equal in your body with the surrounding pressure - as I understand the oxygen mask is only a remedy to allow me breath with an air mixture that contains more oxygen than available at high attitudes and keep me conscious. However, the body itself is still exposed to rapid pressure change and the question here is what to do to relieve some of the damage the pressure change can cause... Probably the post of notfred is also a good suggestion.

Cheers,
RS
RockShock is offline  
Old 25th Oct 2010, 06:28
  #19 (permalink)  
 
Join Date: Aug 2007
Location: Germany
Posts: 37
Likes: 0
Received 0 Likes on 0 Posts
Originally Posted by TheWanderer
Oxygen supply is available for about 20 minutes and cannot be stopped once it is activated due to the nature of the chemical reaction.
True for the aircraft in question. For those that didn't know, there are also systems where the flow of oxygen to individual masks CAN be shut off.
onboard is offline  
Old 25th Oct 2010, 12:56
  #20 (permalink)  
 
Join Date: Aug 2007
Location: London, UK
Posts: 184
Likes: 0
Received 0 Likes on 0 Posts
I have a professional and personal interest in 737 pressurisation problems having had my own encounter several years ago. Luckily no injuries followed and to be fair the pax had little idea what the nature of the problem was, only that we were diverting.

I'm uncertain as to why 5 pax would be injured. As the rubber jungle didn't drop we know that the cabin altitude did not exceed 14,000'. The problem with the QRH drill is that if you only have a slow decompression (statistically much more likely) the a/c will overpressurise in the descent. If there is then a sudden release of pressure (overpressure valve releasing or crew manually depressurising the airframe when below 10,000') injuries could occur. Anyway, well done to the crew for getting it safely back on the ground and not thinking it was the T/O Config warning!

DM
demomonkey is offline  

Thread Tools
Search this Thread

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service

Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.