all of this just to eliminate an emergency exit to fit 2 extra fares on each flight
United finds loose bolts on plug doors during 737 Max 9 inspections
381–390 of 773 posts
Re: United finds loose bolts on plug doors during 737 Max 9 inspections
#382I found it interesting that Boeing did proactively tell airlines to inspect 737 MAXs for a possible loose bolt in a different part of the plane (rudder section) at least 8 days before the January 5th event. Example story: https://www.reuters.com/business/aerospace-defense/boeing-ur... Unfortunately, Boeing did not know they had other issues with the plug door bolts.
They are not related. Probably different types of bolts, for sure different stress types. Rudder assembly is a moving part, these false door panels are not.
Re: United finds loose bolts on plug doors during 737 Max 9 inspections
#383Earlier quoted context omitted.
We don't really get many new car designs do we? Aren't most cars just built on top of old platforms that only see iterative updates?
I think a 2024 Boeing 737 Max is a lot closer to a 1968 737 original than a 2024 Honda Civic is to a 1972 Honda Civic. Car platforms change a lot more, a lot more often, IMHO.
I think you would be mistaken. The car’s engines probably have more in common than the two planes’ engines (low-bypass turbofans in the original, vs. latest high-bypass on the newest ones; engines so different that they changed the plane’s handling enough to require the maligned MCAS). Avionics are entirely different and arguably much more vital to the planes function than a car’s instruments. The interiors are also basically not comparable (sure they have seats but that’s about it).
Re: United finds loose bolts on plug doors during 737 Max 9 inspections
#384Earlier 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.
software development: what is QA?
Re: United finds loose bolts on plug doors during 737 Max 9 inspections
#385I am curious why the door plug is not a plug door — that is, a design wherein the desired panel would be installed from the inside and sealed by the differential pressure, like a cabin door. This part looks more similar to cargo door; those usually have to open outward for space, but what is the design constraint for this case?
Re: United finds loose bolts on plug doors during 737 Max 9 inspections
#386Earlier 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.
Except, of course, from Boeing's aircraft-software QA... which killed hundreds of people already.
Re: United finds loose bolts on plug doors during 737 Max 9 inspections
#387Earlier quoted context omitted.
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…
There’s no way that this is what happened. They’re not building IKEA furniture, everything is tightly check-listed.
Evidently not though....
Re: United finds loose bolts on plug doors during 737 Max 9 inspections
#388I found it interesting that Boeing did proactively tell airlines to inspect 737 MAXs for a possible loose bolt in a different part of the plane (rudder section) at least 8 days before the January 5th event. Example story: https://www.reuters.com/business/aerospace-defense/boeing-ur... Unfortunately, Boeing did not know they had other issues with the plug door bolts.
Imagine the quality of the manufacturing and QA / final inspection to have that kind of issue.
Nope. It is most probably caused by operational stress - rudder assembly is moving, fuselage is also working (compression and decompression cycles on take off and landing, thermal expansion and compression). I bet they don't just put red Loctite on it to keep it from getting loose. My bet is design flaws, not manufacturing or QA.
EDIT: I saw the pictures of bolts with pins and bolts without pins. The ones with pins cannot get loose, the others can. Let's see what happened.
Re: United finds loose bolts on plug doors during 737 Max 9 inspections
#389Earlier quoted context omitted.
Since the aircraft with the incident was extremely new, it is pretty certain that the bolts have not been properly assembled at Boeing, so the problem is with their assembly procedures.
The fuselage of this plane is not built by Boeing. It could be an issue with the contractor, Spirit AeroSystems, who builds it. It could be an issue with some other final configuration procedure. We'll need to wait for the investigation to conclude.
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Re: United finds loose bolts on plug doors during 737 Max 9 inspections
#390I found it interesting that Boeing did proactively tell airlines to inspect 737 MAXs for a possible loose bolt in a different part of the plane (rudder section) at least 8 days before the January 5th event. Example story: https://www.reuters.com/business/aerospace-defense/boeing-ur... Unfortunately, Boeing did not know they had other issues with the plug door bolts.
They are not related. Probably different types of bolts, for sure different stress types. Rudder assembly is a moving part, these false door panels are not.
I think the point is there were at least two sets of loose bolts at the same time.