Soothing to read this while waiting to taxi aboard a different 737 model flown by United!
Luckily this seems to only effect one (newer) model of the 737, though you begin to wonder what was missed in the others.
United finds loose bolts on plug doors during 737 Max 9 inspections
391–400 of 773 posts
Re: United finds loose bolts on plug doors during 737 Max 9 inspections
#392Ed Pierson, a former senior manager at the 737 Max factory in Renton, WA, indicated there have been 20 quality/airworthiness issues post-MCAS to date prior to this latest incident that have gone largely unnoticed by the mainstream media.
It's also worth noting that other ex-employees of Boeing have also raised concerns about substandard structural components made by Ducommun and Boeing's own manufacturing processes for the 737 NG (737-600 to -900). There is no way to know which ones are defective because an unknown number of these critical parts were manufactured inconsistently and haphazardly by hand when they were supposed to be CNC'ed and Boeing just slapped them in without much care. The net result is an average Boeing 737 NG is variably structurally weaker than previous models, and prone to fuselage breakup on hard landings, runway overruns, and possibly in-flight during extreme turbulence. Level 2 corrosion on structural components only 8 years old is what happens when nonconforming, trash parts are passed off as "conforming".
Around 2009, the DOJ made a false statement that the NTSB said the NTSB concluded structural components were "not responsible" for AA 331. These were absolute lies drafted by Boeing's lawyer, Mr. Cole, as no conclusion had been yet reached. In a subsequent sworn video statement, the DOJ official admits they spoke Boeing's words largely verbatim.
This is what happens when publicly-traded corporations are run by MBAs who gut a company's core competencies for short-term profits and are allowed to largely regulate themselves as a consequent of regulatory capture and the corrosive influence of elected officials who accept "campaign support" and gold bars.
Re: United finds loose bolts on plug doors during 737 Max 9 inspections
#393Earlier quoted context omitted.
I think the concern is more the attitude that allowed this to happen, despite all the issues Boeing has had.
Yes, this seems like a top to bottom culture rot problem at Boeing sacrificing quality control in exchange for reduced costs. A few years ago, I had read that certain airlines demanded planes manufacturered in Washington rather than South Carolina, and I wonder if that information actually ends up being a useful signal for better quality planes. https://www.postandcourier.com/business/airline-surveys-poin... https://…
> A few years ago, I had read that certain airlines demanded planes manufacturered in Washington rather than South Carolina, and I wonder if that information actually ends up being a useful signal for better quality planes.
The one with the blown door plug supposedly came off the Renton assembly line. No one is safe.
Re: United finds loose bolts on plug doors during 737 Max 9 inspections
#394Earlier quoted context omitted.
IIRC every bolt's torque value needs to be logged any time it's (re)fastened. At least that's true for aircraft engine maintenance, not sure if it applies to the assembly process of the airframe, I'd sure hope so!
Which doesn't rule out, say, a design flaw that allows the bolt to loosen over time under certain circumstances.
The Max 9 has been in service since 2018 though, I think if it was a design issue it would have occurred before now. This seems like a Manufacturing QA “escape” to me. Some bolt was either not installed properly or not tightened to the proper spec, QA did not catch it
Re: United finds loose bolts on plug doors during 737 Max 9 inspections
#395Earlier quoted context omitted.
There’s no way that this is what happened. They’re not building IKEA furniture, everything is tightly check-listed.
Evidently not though....
> Evidently not though
Bolts can be loosened by the physical and thermal stresses of use if there is a design flaw. So it’s not evidently an assembly QA problem.
Re: United finds loose bolts on plug doors during 737 Max 9 inspections
#396Earlier quoted context omitted.
Imagine the quality of the manufacturing and QA / final inspection to have that kind of issue.
I expect even at its worst, software development could learn a lot from aircraft QA. Especially since most shops have pretty much tossed professional career QA out the window.
QA was literally invented for the airline industry.
Software QA when actually practiced is more advanced now than airline QA.
Re: United finds loose bolts on plug doors during 737 Max 9 inspections
#397On at least 5 airplanes? Of one airline? Are loose bolts a minor issue, or is it as insane as it reads?
No, it's as insane as it reads. It means people were careless and sloppy during assembly. Think of it like seeing "one cockroach in your kitchen." It's not one cockroach. You just haven't opened up the rest of the walls.
When a junior software engineer drops a table in production, we don’t say the junior engineer was sloppy. We say the protections and process in place were bad.
I don’t like how the sentence in this parent comment blames individuals for process problems.
Re: United finds loose bolts on plug doors during 737 Max 9 inspections
#398Check out this video showing how the plug is supposed to be installed: https://youtu.be/maLBGFYl9_o?t=540 Some of the bolts that would be loosened when the plug is opened during maintenance have a pin to prevent them from turning. That pin is present in this photo: https://x.com/byerussell/status/1744460136855294106?s=46&t=s... However, the same photo shows other critical bolts that hold the whole hinge on the door a…
More rampant speculation! Some quotes from this article: https://www.reuters.com/business/aerospace-defense/spirit-ae... > 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 no…
I’m no MBA or aerospace engineer, but why sub-contract the fuselage? I get subbing engines, since engine designs can be used on/adapted to other (possibly non-Boeing) airframes, hence opening up economies of scale, etc. But the fuselage is most of the plane by mass and integral to the design of everything else. If you don’t like making fuselages, maybe you should get out of the aircraft business. Was this just a union-busting thing?
Re: United finds loose bolts on plug doors during 737 Max 9 inspections
#399all of this just to eliminate an emergency exit to fit 2 extra fares on each flight
Honestly I'm surprised why airlines aren't being designed for the slumlord airliner at this point. its pretty obvious from the haphazard window placement on any airplane that it was built to have more legroom but they slid the seats narrower on the seat rails. USB ports never work and power outlets are bent loose to not hold anything plugged into them. Might as well narrow the windows accordingly and ship the plane without cabin electric to save a few cents on initial cost.
Re: United finds loose bolts on plug doors during 737 Max 9 inspections
#400This is the the best update I have seen so far on the incident Alaska Max 9.
The presenter is a 777 pilot and A&P mechanic. Released 2hrs ago.