737 max loses window
Discussion
airbusA346 said:
There's over 200 in service, so only a certain specification is under scrutiny. Alaska have already checked some of there. According to the below article it takes 4-8 hours to check each aircraft.
https://edition.cnn.com/2024/01/06/us/alaska-airli...
I know theres pressure on, but it seems stupendously fast to already have carried out the investigation and have the check procedure rolled out for something that should be unprecedented. I mean they haven't even found the door yet have they?https://edition.cnn.com/2024/01/06/us/alaska-airli...
Similar thing happened to me. I was flying in a military aircraft in Afghanistan. Emergency exit door became dislodged and blew into the aircraft. The first thing I knew was like a cloud/dust forming in the cabin and extreme temp drop. We managed to get the door back into its position and land at Camp Bastion. Once it was all checked we took off again and landed in Kabul.
Teddy Lop said:
airbusA346 said:
There's over 200 in service, so only a certain specification is under scrutiny. Alaska have already checked some of there. According to the below article it takes 4-8 hours to check each aircraft.
https://edition.cnn.com/2024/01/06/us/alaska-airli...
I know theres pressure on, but it seems stupendously fast to already have carried out the investigation and have the check procedure rolled out for something that should be unprecedented. I mean they haven't even found the door yet have they?https://edition.cnn.com/2024/01/06/us/alaska-airli...
MarkwG said:
Teddy Lop said:
airbusA346 said:
There's over 200 in service, so only a certain specification is under scrutiny. Alaska have already checked some of there. According to the below article it takes 4-8 hours to check each aircraft.
https://edition.cnn.com/2024/01/06/us/alaska-airli...
I know theres pressure on, but it seems stupendously fast to already have carried out the investigation and have the check procedure rolled out for something that should be unprecedented. I mean they haven't even found the door yet have they?https://edition.cnn.com/2024/01/06/us/alaska-airli...
I'd have expected the investigation alone to have taken months, as they look to uncover any and every failure through the design, construction, testing and certification that have lead to what could have easily been a catastrophy. You can't check the aircraft unless you first know exactly what happened and what to check, and it's usually (and should be) more than one solitary obvious seeming point of failure. Weeks would be a fast investigation.
Doesn't feel right..
Not giving a pass to Boeing by any means, but as always this goes a little deeper..
The aperture is filled with a door with latching mechanism, just like normal other than there are no control on the inside for it to be opened, should the airline (or future owner) wish, it can be converted back to an emergency exit.
Video here https://www.youtube.com/watch?v=I9EvHpf8jZg look in the comments, a retired Boeing engineer explains exactly how the door and latching mechanism works, he also notes they are now made by a 3rd party supplier.
Its also been divulged that the aircraft in question had pressurisation issues on the 4th, both immediately before and during flight. Unclear at the present time if Alaska did any maintenace but they did remove it from ETOPS operations. in aoccrdoance with regulations https://theaircurrent.com/feed/dispatches/alaska-7...
Assuming this was a manufacturing/asembly defect the question is how does this happen, how does it get past QA (no doubt, both Boeing and the 3rd party will point fingers at each other) but also are procedures/regulations for handling aircraft with reported pressurisation issues suitable/fit for purpose ?
I assume NTSB will be investigating, it'll be interesting to see what reccomendations they make to the FAA.
Edit: reading a bit further, Spirit Aero actually make the entire fuselage, not just the doors/plugs. Some people are of the understanding that a plug is just bolted in (or maybe not in this case) rather than relying on a "hidden" door latch mechanism. Either way, it would seem the main issue is still QA.
The aperture is filled with a door with latching mechanism, just like normal other than there are no control on the inside for it to be opened, should the airline (or future owner) wish, it can be converted back to an emergency exit.
Video here https://www.youtube.com/watch?v=I9EvHpf8jZg look in the comments, a retired Boeing engineer explains exactly how the door and latching mechanism works, he also notes they are now made by a 3rd party supplier.
Its also been divulged that the aircraft in question had pressurisation issues on the 4th, both immediately before and during flight. Unclear at the present time if Alaska did any maintenace but they did remove it from ETOPS operations. in aoccrdoance with regulations https://theaircurrent.com/feed/dispatches/alaska-7...
Assuming this was a manufacturing/asembly defect the question is how does this happen, how does it get past QA (no doubt, both Boeing and the 3rd party will point fingers at each other) but also are procedures/regulations for handling aircraft with reported pressurisation issues suitable/fit for purpose ?
I assume NTSB will be investigating, it'll be interesting to see what reccomendations they make to the FAA.
Edit: reading a bit further, Spirit Aero actually make the entire fuselage, not just the doors/plugs. Some people are of the understanding that a plug is just bolted in (or maybe not in this case) rather than relying on a "hidden" door latch mechanism. Either way, it would seem the main issue is still QA.
Edited by Crafty_ on Sunday 7th January 11:02
Crafty_ said:
Some people are of the understanding that a plug is just bolted in (or maybe not in this case) rather than relying on a "hidden" door latch mechanism. Either way, it would seem the main issue is still QA.
One imagines part of the problem may be that when a "permanently closed" exit door is blanked off behind interior panelling it's not the easy to inspect it on a routine basis. The outside is flush with the fuselage and any closing/locking mechanism must, by definition, be on the inside. There is no hidden latch mechanism behind the panel, a photo of one is on Pprune. It’s got a bottom hinge and a top cam, but has no release mechanism behind the plastic panel.
Looks like if the bolts had an issue that it can self release though, as it still has the springs that push it up and out, albeit it also has tethers.
Looks like if the bolts had an issue that it can self release though, as it still has the springs that push it up and out, albeit it also has tethers.
Crafty_ said:
Not giving a pass to Boeing by any means, but as always this goes a little deeper..
The aperture is filled with a door with latching mechanism, just like normal other than there are no control on the inside for it to be opened, should the airline (or future owner) wish, it can be converted back to an emergency exit.
Video here https://www.youtube.com/watch?v=I9EvHpf8jZg look in the comments, a retired Boeing engineer explains exactly how the door and latching mechanism works, he also notes they are now made by a 3rd party supplier.
Its also been divulged that the aircraft in question had pressurisation issues on the 4th, both immediately before and during flight. Unclear at the present time if Alaska did any maintenace but they did remove it from ETOPS operations. in aoccrdoance with regulations https://theaircurrent.com/feed/dispatches/alaska-7...
Assuming this was a manufacturing/asembly defect the question is how does this happen, how does it get past QA (no doubt, both Boeing and the 3rd party will point fingers at each other) but also are procedures/regulations for handling aircraft with reported pressurisation issues suitable/fit for purpose ?
I assume NTSB will be investigating, it'll be interesting to see what reccomendations they make to the FAA.
Edit: reading a bit further, Spirit Aero actually make the entire fuselage, not just the doors/plugs. Some people are of the understanding that a plug is just bolted in (or maybe not in this case) rather than relying on a "hidden" door latch mechanism. Either way, it would seem the main issue is still QA.
I had seen some mention that there was strike action at Spirit when this fuselage could have been on the production line in Wichita.The aperture is filled with a door with latching mechanism, just like normal other than there are no control on the inside for it to be opened, should the airline (or future owner) wish, it can be converted back to an emergency exit.
Video here https://www.youtube.com/watch?v=I9EvHpf8jZg look in the comments, a retired Boeing engineer explains exactly how the door and latching mechanism works, he also notes they are now made by a 3rd party supplier.
Its also been divulged that the aircraft in question had pressurisation issues on the 4th, both immediately before and during flight. Unclear at the present time if Alaska did any maintenace but they did remove it from ETOPS operations. in aoccrdoance with regulations https://theaircurrent.com/feed/dispatches/alaska-7...
Assuming this was a manufacturing/asembly defect the question is how does this happen, how does it get past QA (no doubt, both Boeing and the 3rd party will point fingers at each other) but also are procedures/regulations for handling aircraft with reported pressurisation issues suitable/fit for purpose ?
I assume NTSB will be investigating, it'll be interesting to see what reccomendations they make to the FAA.
Edit: reading a bit further, Spirit Aero actually make the entire fuselage, not just the doors/plugs. Some people are of the understanding that a plug is just bolted in (or maybe not in this case) rather than relying on a "hidden" door latch mechanism. Either way, it would seem the main issue is still QA.
Edited by Crafty_ on Sunday 7th January 11:02
[i]"The 737 MAX 9, currently Boeing's largest single-aisle, seating up to 220 people, includes an optional extra door to allow for the approved number of evacuation paths whenever carriers opt to install the maximum number of seats.
But most airlines using the jet have chosen a looser layout based on a smaller number of seats and do not need the surplus door, which adds weight and reduces flexibility in the cabin. Instead the door is deactivated before delivery, using a "plug."
Other optional doors or fill-in replacement structures were also offered on a predecessor model, the 737-900ER.
As part of the production process, Spirit builds fuselages for 737s and sends them by train with the special door assembly “semi-rigged", one of the people said.
“They are fitted but not completed," the person said.
At its Renton, Washington, plant, Boeing typically removes the pop-out, or non-functioning, door and uses the gap to load interiors. Then, the part is put back and the installation in completed. Finally, the hull is pressurized to 150% to make sure everything is working correctly, the person said.
The process means that finding out where any flaw was introduced during assembly may not be clear-cut, said the sources, who asked not to be named as details of the probe are confidential.[/i]
https://www.reuters.com/business/aerospace-defense...
So it could also be an additional Boeing QC issue.
Teddy Lop said:
MarkwG said:
Teddy Lop said:
airbusA346 said:
There's over 200 in service, so only a certain specification is under scrutiny. Alaska have already checked some of there. According to the below article it takes 4-8 hours to check each aircraft.
https://edition.cnn.com/2024/01/06/us/alaska-airli...
I know theres pressure on, but it seems stupendously fast to already have carried out the investigation and have the check procedure rolled out for something that should be unprecedented. I mean they haven't even found the door yet have they?https://edition.cnn.com/2024/01/06/us/alaska-airli...
I'd have expected the investigation alone to have taken months, as they look to uncover any and every failure through the design, construction, testing and certification that have lead to what could have easily been a catastrophy. You can't check the aircraft unless you first know exactly what happened and what to check, and it's usually (and should be) more than one solitary obvious seeming point of failure. Weeks would be a fast investigation.
Doesn't feel right..
MarkwG said:
The investigation in to what led up to losing the door will take months: the resolution may be perfectly obvious from the damage around the door frame. The two are not mutually exclusive.
At risk of stating the obvious they need to find that door/plug. Even then, any bolts or other fixings are likely to be miles away and impossible to recover, judging by the appearance of the lugs on the aircraft.Way back in 1989 a three engine McDonnell Douglas DC10 jet suffered total failure of it's third engine, the one on the tail. That aircraft crashed during an emergency landing attempt. The rear engine's fan disk and blade assembly, about 8 feet diameter, couldn't be found at the scene of the accident. Three months after the crash, a farmer discovered most of the fan disk in her cornfield, which earned her the $50,000 reward offered by General Electric, who'd built the engine. Most of the missing fan blades were later found nearby. The cause of the crash was found to be a fatigue crack in the disk which arose from a manufacturing defect that had not been identified during previous maintenance despite the presence of fluorescent dye. The engine had run OK for 18 years prior to the failure.
Panamax said:
.
Way back in 1989 a three engine McDonnell Douglas DC10 jet suffered total failure of it's third engine, the one on the tail. That aircraft crashed during an emergency landing attempt.
Sioux city....amazing job the crew definitly earned their money that day getting the aircraft back to an airport with decent fire and rescue cover will have saved lives.Way back in 1989 a three engine McDonnell Douglas DC10 jet suffered total failure of it's third engine, the one on the tail. That aircraft crashed during an emergency landing attempt.
The more I read about this, the more I come to the conclusion that the four bolts were left off during assembly. I think Boeing already know this having looked at the lack of damage to the fixings, which would explain why they were able to roll out an inspection so quickly (otherwise how could they determine what they were looking for in the inspection).
ETA The screenshots from a YT show how the bolts are installed, and how leaving them off wouldn’t necessarily come to light immediately.
ETA The screenshots from a YT show how the bolts are installed, and how leaving them off wouldn’t necessarily come to light immediately.
Edited by tim0409 on Sunday 7th January 20:03
tim0409 said:
The more I read about this, the more I come to the conclusion that the four bolts were left off during assembly. I think Boeing already know this having looked at the lack of damage to the fixings, which would explain why they were able to roll out an inspection so quickly (otherwise how could they determine what they were looking for in the inspection).
It does look that way; 3 of the 4 could be missing and the plug would still be held in place as there's no force on the bolts.tim0409 said:
The more I read about this, the more I come to the conclusion that the four bolts were left off during assembly. I think Boeing already know this having looked at the lack of damage to the fixings, which would explain why they were able to roll out an inspection so quickly (otherwise how could they determine what they were looking for in the inspection).
The speed of resolution prompted me too to ponder that someone knew *exactly* what was wrong... But the procedure of idiocy is normally DENYDENYDENYDENYDENYDENYDENYDENYDENY no idea guv'nuhGassing Station | Boats, Planes & Trains | Top of Page | What's New | My Stuff