Here's a statement of the obvious: The opinions expressed here are those of the participants, not those of the Mutual Fund Observer. We cannot vouch for the accuracy or appropriateness of any of it, though we do encourage civility and good humor.
I was set to fly on my first MAX last night. But missed the connection in Chicago. (Delays … Delays.)
Haven’t kept up with the story. But from the first reports I expected this was likely some plane that had seen many years of service / aging parts. But if it was the Max - holy creepers. These issues just keep compiling. What’s going on at Boeing? Compared to the slightly larger / wider A 319 / 320, the 737 isn’t as comfortable. Boeing must feel they need to compete on a fuel-cost basis. And may not have the financial means to develop a whole new competitor to the A 320 series.
For those who don’t remember, there is a really in-depth & long running thread on the Max in “Off-Topic” back around the time the second one crashed. (maybe around 2018?) In a nutshell, the original 737 dates back to the 1960s or early 70s. Boeing has continuously altered the plane to carry more passengers & weight, fly further & higher (less drag / better fuel economy), operate more autonomously and do a lot of things the original designers never intended.
With all the releases and submodels, it's hard to keep up with this plane. Almost as bad as American Funds's share classes: A, C, F1, F2, F3, T, 529-A, 529-C, 529-F1, 529-F2, 529-F3, 529-T, ABLE-1, ABLE-2, R1, R2, R3, R3E, R4, R5, R5E, R6. And that's after AF took its B/529-B shares (e.g. PGGBX, CGGBX) out of service.
Here, it is only the Boeing 737-Max 9s that are grounded. the 737-800 is from the previous generation (called Next Generation or NG), and the Max 8 is a smaller model than the Max 9. It's the MAX line that was grounded in 2019.
What I do not understand is airplane doors are purposely designed so the lower the outside pressure, the tighter the seal as the positive pressure differential pushes the door tighter. That is why you cannot open a door in md flight.
Yet this "door plug" blew open at 16000 feet when the pressure inside was apparently equal to 4500 feet or so inside.
Bring back the McDonnell Douglass MD80s.. fast planes, flew greatWhatever happened to if it ain't Boeing I ain't going?Not sure if I'd feel comfortable on a dreamliner 787, lot of composite parts on that one and lot of outsourced sub assemblies..
Still a few DC-9 and (stretched) MD-80s flying. While no longer produced, a variant lives on in the Boeing 717, really just a slightly smaller (and more recent) DC-9. Was developed by McDonnell Douglas. Boeing renamed it when the bought the company. Like you, I enjoyed riding on the DC-9 and its variants. And I don’t think there’s a prettier sight in the sky than a DC-9 / MD-80 climbing out.
@BBF - Today’s aircraft actually fly a bit slower on average than when the DC 9 came out. Those were real jet engines with hot exhaust gasses doing the work. Today’s are basically big turbines - spinning blades that suck in large quantities of air, compress and discharge it for thrust. Fuel economy is much better. Noise reduction and environmental factors played a part in the shift as well. Today’s larger passenger jets generally cruise below 600 mph. 550-570 common. But they do fly higher. All the new ones now can cruise well above 40,000 feet / 30,000-35,000 was more common 40-50 years ago. That increased capability is in part due to better management of control surfaces by computer.
"the optional door/exit area was "sealed"/"plugged" in this model? So, was that construction glue that didn't hold? "
Most likely this whole thing will come down to one of the following situations:
• 1) The design and specification of the fuselage emergency exit/window component is inadequate.
• 2) The design and specification of the fuselage emergency exit/window component is acceptable and safe, but the actual fabrication/assembly of that component was faulty. The actual fabrication/assembly of that component is done by Spirit AeroSystems, a Boeing subcontractor. Following is an excerpt from a current report in The Guardian:
Spirit AeroSystems in Wichita, Kansas, manufactured the fuselage. But Boeing completed the complex, two-tier installation process at its plant just outside Seattle, Washington.
Investigators are expected to examine both factories for potential flaws in design, manufacturing and installation, according to sources cited by Reuters. “The assumption is that it was installed or rigged incorrectly,” one source reportedly said. Neither Boeing nor Spirit have commented.
Door plugs have been used to adapt aircraft and offer flexible seating across the industry for years.
• 3) The design and specification of the fuselage emergency exit/window component is acceptable, and the fabrication/assembly of that component was as specified, but the actual installation of that component into the fuselage was not performed correctly, and the safety check of the installation was inadequate or not performed at all.
The present situation is not unique- historically there have been similar situations in aircraft design, assembly, or maintenance which have not shown up until the aircraft was actually placed in service, sometimes with disastrous consequences.
Expanding on possibility #3 above, the fuselage is designed to have an opening which may be used either for an emergency exit, or if that is not required, a window panel. Since the actual installation depends upon the seating configuration specifications of the airline ordering the plane, it is probable that the fuselage section is designed to allow subsequent reconfiguration if the seating arrangement is later changed.
If that is in fact the case, then whichever type of section is inserted into that fuselage space will be held there by some type of mechanical fastening/locking system. The integrity of that locking system would be dependent upon correct installation, alignment, and inspection.
I have been increasingly disillusioned with the assembly practices of Boeing ever since upper management decided that it was more important for them to be located in Virginia so as to be close to the DC political power centers than to be in Seattle where they could actually walk out into the factory and see for themselves what was really going on there.
To me, that pretty well puts Boeing management's evaluation of what is important in making airplanes into perspective.
1/8: From PBS: Diagram of Boeing "Door Plug" and associated hardware fittings
1/9: From The New York Times: Partial Diagram of Boeing "Door Plug" and associated hardware fittings
Note that the NY Times diagram identifies two fittings as "Location of Upper Bolts". However, on the earlier PBS diagram that same hardware is described as "Upper Guide Roller, (2 locations). Neither diagram is detailed enough to clarify this contradiction. One possible explanation is that there may be bolts, not shown, which are used to fasten the upper guide rollers. That, however, is only speculation on my part.
Planes that carry more than about 200 passengers require more emergency exits to comply with safety regulations, while airplanes that carry fewer passengers can be fitted with the door plug instead.
Under ordinary circumstances, most passengers wouldn't notice the door plug at all because it looks similar to a regular window.
Boeing has been using the design for more than a decade without any major incidents, said John Cox, a former pilot who is now a consultant with the company Safety Operating Systems. Door plugs are used on the Boeing 737-900ER, a predecessor of the Max planes, as well as the Max series.
The Alaska Airlines plane had just been delivered on October 31st, according to the NTSB. An auto-pressurization failure light had illuminated in the plane's cockpit three times in prior weeks. Alaska Airlines put a restriction in place that prevented the plane from flying over water to Hawaii, so that it could return more easily to an airport in case of emergency.
What are investigators looking for?
"We know what happened. We don't know fully why," Cox said. "And then the follow up question, of course, is what do we need to do to prevent it from happening again?"
The door plug is held in place by four bolts. And investigators say the condition of those bolts may be telling. "Are the four bolts there? Are the nuts there? Was there deformation or bending of the bolts, of the holes?," Cox said. "All of those things they're going to look at to try to understand the forces that resulted in this plug leaving the airplane."
Investigators at the NTSB will want to examine both the door and the components of the plane where it was attached.
"We have a lot of ability in our lab with our microscopes to really look at some of the components more in depth," NTSB Chair Jennifer Homendy said on Sunday night, "to look at witness marks, to look at any paint transfer, what shape the door was in when found. That can tell them a lot about what occurred."
The door plug, like the rest of the Max 9 fuselage, is manufactured by Spirit AeroSystems, a Boeing supplier based in Wichita, Kansas.
The Federal Aviation Administration said Monday that carriers can begin inspections of about 170 Boeing Max 9 planes which have been grounded after the incident on Friday night.
Note: Blue Italic text emphasis was added to invite comparison to my previous post, above.
The door plug that blew out of an Alaska Airlines flight over Portland, Ore., on Friday has been found in a schoolteacher’s backyard, amid investigations into the explosive depressurization accident that triggered an emergency landing and resulted in extensive damage to the inside of the Boeing 737-9 Max airplane.
Alaska Airlines recorded that the plane’s auto-pressurization fail light — which is designed to signal failures in controlling cabin pressure — had illuminated on three flights in the weeks before Friday’s incident. Those reports, on Dec. 7, Jan. 3 and Jan. 4, prompted tests and a reset from maintenance, Jennifer Homendy, chair of the National Transportation Safety Board (NTSB), said in a news conference Sunday evening.
She added that the airline restricted the plane from flying to Hawaii in case it would need swift landing, and that a later request from Alaska Airlines for a deeper look had gone unfulfilled before the incident Friday.
Well, this is really getting interesting, no? Let's see now... "This airplane seems to be doing something weird with the pressurization... maybe we better not send it out over the ocean... but I guess it's OK to take a chance with passengers flying to California..."
Just a lucky coincidence that the seats next to the door plug were not assigned?? Or maybe, just maybe, someone said "well, if we're going to take a chance with passengers flying to California maybe we better not use those seats" ???
”She added that the airline restricted the plane from flying to Hawaii in case it would need swift landing, and that a later request from Alaska Airlines for a deeper look had gone unfulfilled before the incident Friday.”
Knowing that might keep me from getting aboard for even a short flight to Timbuktu. Lawyers must be scrambling all over the place now.
Oh, yes. Everyone will get "lawyered-up." Surprised the bolt was found so soon, in a teacher's backyard. Will airlines everywhere cancel their orders for new Max-9 737s? It's very rare to take planes out of service. I remember than the L-1011 is one. Maybe for not the best reasons? But maybe it's still flying CARGO only? And the early British jet: the Comet. https://www.rafmuseum.org.uk/research/archive-exhibitions/comet-the-worlds-first-jet-airliner/
When I was a lot younger (under 40 or 50), during roughly the period from 1965 to 1995, it was common to have 1 or 2 fatal crashes of domestic flights every year. Sometimes more. We more or less took them for granted. Now they are so rare. The last one (domestic) I can recall with substantial loss of life was about 10 years ago when a poorly trained crew crashed a turbo-prop commuter plane somewhere in New York while landing under icing conditions killing the 40 or so passengers aboard.
But, the NTSB and industry in general have done a great deal to prevent really serious loss of life in this country.. One I remember sadly was the Northwest MD-80 that crashed shortly after attempting to take off from Detroit in 1987 bound for California. A wonderful young lady I’d had the privilege of having in one of my classes a few years earlier perished along with more than 150 others in that one.
Like I said - such crashes domestically were common and taken for granted for decades. Virtually every type / make of aircraft participated. You always felt like you were “rolling the dice” a bit when you climbed aboard one.
Air Florida. From Washington, D.C. Horrible cold, snow that day. A few survivors were plucked out of the Potomac. And I recall that crash in the dark and the snow, near Buffalo.
Above, I've added a new graphic from the New York Times which purports to illustrate the location of the mysterious "bolts" which are receiving so much interest. However this new information only seems to muddy the waters even more.
I don’t know if it’s been commented on yet, but it’s remarkable there were only 3 or 4 unoccupied seats on that craft. And just by chance, 2 of those happened to be next to the door that blew out. The crew must have done a fantastic job reacting and quickly descending from 17,000 feet to an acceptable altitude for non-pressurized flight.
Why were those two seats empty? Possibly they afforded a bit of extra leg room due to proximity to door (or door plug) and they might have carried a premium price and thereby gotten overlooked by ticketing passengers. However, usually anything with a little extra room sells out fast.
Well, this is really getting interesting, no? Let's see now... "This airplane seems to be doing something weird with the pressurization... maybe we better not send it out over the ocean... but I guess it's OK to take a chance with passengers flying to California..."
Just a lucky coincidence that the seats next to the door plug were not assigned?? Or maybe, just maybe, someone said "well, if we're going to take a chance with passengers flying to California maybe we better not use those seats" ???
As you can see, there's no "extra" legroom to be seen...
“As you can see, there's no "extra" legroom to be seen...”
All I can see is a big hole. Woosh!
Actually - On second look, there appears to be no leg room. Something seems “off” in that photo. Just a guess - but with the evac door installed, those 2 seats might be removed to allow a wider passageway to the exit. That’s how it looks to me.
There’s an extra panel (actually 2) up against the 2 visible seats in front. Probably intended to better define the evacuation passageway - and also maybe to limit the ability of those forward seats to recline.
A bit curious - photo shows just 2 seats per row. Of course, except for first class, on a 737 seating is 3X3 (3 on a side). So, there’s probably another seat just not visible in photo.
Heard comment that had the door left the plane at a much higher altitude , results may have turned in a second, & not for the better ! This happen at 17,000 ft. & believe they can "cruise" up to 37,000 ft.. I have no idea as to average flight altitude.
Heard comment that had the door left the plane at a much higher altitude , results may have turned in a second, & not for the better ! This happen at 17,000 ft. & believe they can "cruise" up to 37,000 ft.. I have no idea as to average flight altitude.
Well - I have a good set of noise cancelling headphones I only use flying. Bought them after the airlines began bombarding us with loud advertising for their various credit cards, mileage programs, etc. (“captive audience” of course). Might have helped dampen the noise a bit.
OTHO - There’s a media report that the first officer’s headset was tore off his head and sucked through the hole. So - might not have worked.
To your point @Derf - Yes - higher altitude would increase the relative pressure differential (inside / outside) Higher would have been worse - but 17,000 ain’t exactly low. They don’t venture above 10,000 without a pressurized cabin from my past observations. Sometimes on very short flights they cruise in the 17,000 foot area. My guess is that’s more fuel efficient (despite increased drag) than climbing to 30,000+ for only a short while. ATC has a lot to say about that as well.
@Derf - I found 41,000 feet as the maximum cruising altitude for later year (recent) 737s. Certainly there are some variables in there like loading, air temp, etc. But a good rough number.
Comments
Haven’t kept up with the story. But from the first reports I expected this was likely some plane that had seen many years of service / aging parts. But if it was the Max - holy creepers. These issues just keep compiling. What’s going on at Boeing? Compared to the slightly larger / wider A 319 / 320, the 737 isn’t as comfortable. Boeing must feel they need to compete on a fuel-cost basis. And may not have the financial means to develop a whole new competitor to the A 320 series.
For those who don’t remember, there is a really in-depth & long running thread on the Max in “Off-Topic” back around the time the second one crashed. (maybe around 2018?) In a nutshell, the original 737 dates back to the 1960s or early 70s. Boeing has continuously altered the plane to carry more passengers & weight, fly further & higher (less drag / better fuel economy), operate more autonomously and do a lot of things the original designers never intended.
Here, it is only the Boeing 737-Max 9s that are grounded. the 737-800 is from the previous generation (called Next Generation or NG), and the Max 8 is a smaller model than the Max 9. It's the MAX line that was grounded in 2019.
https://simpleflying.com/boeing-737-max-vs-737-800/
(Simplifying? Ha!)
How every Boeing 737 MAX was grounded in five days
https://multimedia.scmp.com/news/world/article/3003901/boeing-737-grounded/index.html
Whatever happened to if it ain't Boeing I ain't going?
Not sure if I'd feel comfortable on a dreamliner 787, lot of composite parts on that one and lot of outsourced sub assemblies....
Yeesh
Yet this "door plug" blew open at 16000 feet when the pressure inside was apparently equal to 4500 feet or so inside.
@BBF - Today’s aircraft actually fly a bit slower on average than when the DC 9 came out. Those were real jet engines with hot exhaust gasses doing the work. Today’s are basically big turbines - spinning blades that suck in large quantities of air, compress and discharge it for thrust. Fuel economy is much better. Noise reduction and environmental factors played a part in the shift as well. Today’s larger passenger jets generally cruise below 600 mph. 550-570 common. But they do fly higher. All the new ones now can cruise well above 40,000 feet / 30,000-35,000 was more common 40-50 years ago. That increased capability is in part due to better management of control surfaces by computer.
Most likely this whole thing will come down to one of the following situations:
• 1) The design and specification of the fuselage emergency exit/window component is inadequate.
• 2) The design and specification of the fuselage emergency exit/window component is acceptable and safe, but the actual fabrication/assembly of that component was faulty. The actual fabrication/assembly of that component is done by Spirit AeroSystems, a Boeing subcontractor. Following is an excerpt from a current report in The Guardian: • 3) The design and specification of the fuselage emergency exit/window component is acceptable, and the fabrication/assembly of that component was as specified, but the actual installation of that component into the fuselage was not performed correctly, and the safety check of the installation was inadequate or not performed at all.
The present situation is not unique- historically there have been similar situations in aircraft design, assembly, or maintenance which have not shown up until the aircraft was actually placed in service, sometimes with disastrous consequences.
Expanding on possibility #3 above, the fuselage is designed to have an opening which may be used either for an emergency exit, or if that is not required, a window panel. Since the actual installation depends upon the seating configuration specifications of the airline ordering the plane, it is probable that the fuselage section is designed to allow subsequent reconfiguration if the seating arrangement is later changed.
If that is in fact the case, then whichever type of section is inserted into that fuselage space will be held there by some type of mechanical fastening/locking system. The integrity of that locking system would be dependent upon correct installation, alignment, and inspection.
I have been increasingly disillusioned with the assembly practices of Boeing ever since upper management decided that it was more important for them to be located in Virginia so as to be close to the DC political power centers than to be in Seattle where they could actually walk out into the factory and see for themselves what was really going on there.
To me, that pretty well puts Boeing management's evaluation of what is important in making airplanes into perspective.
1/8: From PBS: Diagram of Boeing "Door Plug" and associated hardware fittings
1/9: From The New York Times: Partial Diagram of Boeing "Door Plug" and associated hardware fittings
Note that the NY Times diagram identifies two fittings as "Location of Upper Bolts". However, on the earlier PBS diagram that same hardware is described as "Upper Guide Roller, (2 locations). Neither diagram is detailed enough to clarify this contradiction. One possible explanation is that there may be bolts, not shown, which are used to fasten the upper guide rollers. That, however, is only speculation on my part.
Following are edited excerpts from a current NPR report:
Planes that carry more than about 200 passengers require more emergency exits to comply with safety regulations, while airplanes that carry fewer passengers can be fitted with the door plug instead.
Under ordinary circumstances, most passengers wouldn't notice the door plug at all because it looks similar to a regular window.
Boeing has been using the design for more than a decade without any major incidents, said John Cox, a former pilot who is now a consultant with the company Safety Operating Systems. Door plugs are used on the Boeing 737-900ER, a predecessor of the Max planes, as well as the Max series.
The Alaska Airlines plane had just been delivered on October 31st, according to the NTSB. An auto-pressurization failure light had illuminated in the plane's cockpit three times in prior weeks. Alaska Airlines put a restriction in place that prevented the plane from flying over water to Hawaii, so that it could return more easily to an airport in case of emergency.
What are investigators looking for?
"We know what happened. We don't know fully why," Cox said. "And then the follow up question, of course, is what do we need to do to prevent it from happening again?"
The door plug is held in place by four bolts. And investigators say the condition of those bolts may be telling. "Are the four bolts there? Are the nuts there? Was there deformation or bending of the bolts, of the holes?," Cox said. "All of those things they're going to look at to try to understand the forces that resulted in this plug leaving the airplane."
Investigators at the NTSB will want to examine both the door and the components of the plane where it was attached.
"We have a lot of ability in our lab with our microscopes to really look at some of the components more in depth," NTSB Chair Jennifer Homendy said on Sunday night, "to look at witness marks, to look at any paint transfer, what shape the door was in when found. That can tell them a lot about what occurred."
The door plug, like the rest of the Max 9 fuselage, is manufactured by Spirit AeroSystems, a Boeing supplier based in Wichita, Kansas.
The Federal Aviation Administration said Monday that carriers can begin inspections of about 170 Boeing Max 9 planes which have been grounded after the incident on Friday night.
Note: Blue Italic text emphasis was added to invite comparison to my previous post, above.
Just a lucky coincidence that the seats next to the door plug were not assigned?? Or maybe, just maybe, someone said "well, if we're going to take a chance with passengers flying to California maybe we better not use those seats" ???
Knowing that might keep me from getting aboard for even a short flight to Timbuktu. Lawyers must be scrambling all over the place now.
https://www.rafmuseum.org.uk/research/archive-exhibitions/comet-the-worlds-first-jet-airliner/
When I was a lot younger (under 40 or 50), during roughly the period from 1965 to 1995, it was common to have 1 or 2 fatal crashes of domestic flights every year. Sometimes more. We more or less took them for granted. Now they are so rare. The last one (domestic) I can recall with substantial loss of life was about 10 years ago when a poorly trained crew crashed a turbo-prop commuter plane somewhere in New York while landing under icing conditions killing the 40 or so passengers aboard.
But, the NTSB and industry in general have done a great deal to prevent really serious loss of life in this country.. One I remember sadly was the Northwest MD-80 that crashed shortly after attempting to take off from Detroit in 1987 bound for California. A wonderful young lady I’d had the privilege of having in one of my classes a few years earlier perished along with more than 150 others in that one.
Like I said - such crashes domestically were common and taken for granted for decades. Virtually every type / make of aircraft participated. You always felt like you were “rolling the dice” a bit when you climbed aboard one.
Why were those two seats empty? Possibly they afforded a bit of extra leg room due to proximity to door (or door plug) and they might have carried a premium price and thereby gotten overlooked by ticketing passengers. However, usually anything with a little extra room sells out fast.
All I can see is a big hole. Woosh!
Actually - On second look, there appears to be no leg room. Something seems “off” in that photo. Just a guess - but with the evac door installed, those 2 seats might be removed to allow a wider passageway to the exit. That’s how it looks to me.
There’s an extra panel (actually 2) up against the 2 visible seats in front. Probably intended to better define the evacuation passageway - and also maybe to limit the ability of those forward seats to recline.
A bit curious - photo shows just 2 seats per row. Of course, except for first class, on a 737 seating is 3X3 (3 on a side). So, there’s probably another seat just not visible in photo.
OTHO - There’s a media report that the first officer’s headset was tore off his head and sucked through the hole. So - might not have worked.
To your point @Derf - Yes - higher altitude would increase the relative pressure differential (inside / outside) Higher would have been worse - but 17,000 ain’t exactly low. They don’t venture above 10,000 without a pressurized cabin from my past observations. Sometimes on very short flights they cruise in the 17,000 foot area. My guess is that’s more fuel efficient (despite increased drag) than climbing to 30,000+ for only a short while. ATC has a lot to say about that as well.
@Derf - I found 41,000 feet as the maximum cruising altitude for later year (recent) 737s. Certainly there are some variables in there like loading, air temp, etc. But a good rough number.