This is basically the FAA putting everyone on notice by saying "yo, we found a few that were real bad so y'all gotta make sure you check yours real good." It's a bushing on a control surface, of course it wears over the course of normal use. If it sat for months and corroded slightly the corrosion would cause it to wear faster. This is all perfectly normal. These things are meant to fly so the engineering more often favors dainty little parts that can barely do the job with maintenance tacked on over heavier overbuilt parts that you don't need to check as much.

>I can only imagine that in aviation, there are even more advanced tools, especially with a well-respected corp like Boeing.

Lol. "More advanced" often being something a long the lines of a $100000 dollar go-nogo gauge because you don't trust your employees to read a measuring tool.

>If these flapper bushings are bad consistently,

Bushings are probably (i.e. "almost certainly" but I wasn't in that engineering meeting so I don't know for sure) a wear item and of course they could build beefy ones but the OEM has to balance between weight and maintenance hours. Doesn't surprise me that a little extra corrosion grit in there makes them go out of spec fast.

>if guys are bringing me the same rifle with the same issue over and over, it makes me really uneasy because it's inefficient for my shop, and it points to carelessness from the vendor

The whole value proposition of a Hi-point or a Chinese pump shotgun is that the manufacturing tolerances are wide opens so that your wallet doesn't have to be.

Suffice to say, nobody in my unit was rolling out with Hi-point.

Thanks for your post, you are clearly much more aware of aviation than I am, and what you've explained makes perfect sense.

I could've clarified that while I wasn't in control of ordinance, I had some level of trust in those who were, as I'd expect the engineers at Boeing have some level of trust in the designs and blueprints they are working on.

I'm curious to know more about the attitude that an engineer might have about their role in Boeing. It often seems that Boeing is being dragged through the mud, and rightfully so in some part due to the 737 MAX. However, I know enough to know that shit often rolls downhill, even onto those who never ate in the first place. I imagine there could be some disgruntled vibes going around in the shops, far from the boardrooms.

It's not necessary to use calipers to measure these tolerances. In this case talking about clearance between two parts you just use a feeler gauge which is a calibrated thickness of metal. If the documentation says no more than X mm, you grab your X gauge and make sure it doesn't fit. It's the same if you're working on a 737 or your John Deere.

They're measuring it to ensure corrosion hasn't thrown it out of spec, right? Not that it wasn't manufactured to spec?

Excellent point, shows you how much of an engineer I'm NOT. That's probably a big point too.

Surely there's some sort of chart they've made for all these parts and how fast they're allowed to decay, given some number of flight-hours?

I believe there are procedures/checklists for placing aircraft in and out of storage which are different than those used for normal operation, because the conditions are different. It is my understanding that this directive is an additional check that would be performed during the typical storage procedures.

> given some number of flight-hours?

I think the issue here is the lack of flight-hours. These parts were designed and specified for an in-use plane, not one that sits around.

An airplane is an extremely expensive asset and they are typically almost constantly in service. It's very rare for one to be idled for months at a time.

yes - this is related to non-routine maintenance. I assume operation prevents moisture forming that can corrode. Storage for several weeks or months means this is like a more stringent used car "road worthiness" inspection.

Boeing used to be a well respected company. At least until the merger with McDonnell Douglas, which turned it from an engineering driven company to a financial engineering company.

Eh there were several phases of stupidity there.

757 to replace the 727 when the 727 was doing quite fine. That said the 757 is a great plane and proved out well, just had a high price tag that really held it back.

The delay and screwing around with getting the 767 out there for fear it would mess with 747 sales. Let airbus get ahead with wide-bodies and took longer than expected to get the ER variants out.

Post McDonnell Dougals:

The handling of the 717 (basically shutting it down when there was demand). Could have had an impact if they wanted to bring it to the regional space (to go against the crj900+ and EMB ejets).

Oh so much in the planning and execution of the 787.

The continued extending of the 737 well beyond what it should be (see the 900, the MAX).

And in turn the same had happened with Douglas; McDonnell's investment was reluctantly accepted in order to save the company but utterly changed the culture from engineering to finance.

I really struggle to understand how you could have used the term "well-respected" here. It ain't muscle memory, this was done deliberately. Could you explain how you can refer to Boeing being well-respected after the 737 MAX fiasco? Maybe I am missing something.

[edit] remove a word

They've had some big screw-ups that were well covered on HN. But from 2014 to 2018 they were consistently the biggest and most profitable aerospace company in the world[1]. You don't get there by being disrespected and all-around shitty.

[1] https://en.wikipedia.org/wiki/Aerospace_manufacturer#Largest...

As a long time lurker I finally had to create an account to reply to you. Boeing was indeed extremely large and profitable. Building such a successful enterprise came from lifetimes of work with dedication to excellence in engineering, manufacturing, safety, etc. Unfortunately we are seeing that a decade or so of attacking these values is enough to destroy even a giant. I do not believe that we are seeing just a streak of bad luck. Off the top of my head, let's review a few of Boeing's recent big projects.

787 - Historically over budget and delayed. Failed static wing deflection test, showing how much we can trust the FEA work. In cockpit battery fires led to a historic worldwide grounding of Boeing commercial aircraft. A NTSB report blamed (in part) Boeing engineers for not considering worst case scenario for a lithium battery in a cockpit compartment that contained no fire suppression system. A grounding like the one OP linked is not unprecedented, it is of the 'the plane is grounded until it passes an inspection' type. The battery fire issue led to a 'all planes are grounded until Boeing has a fix.' I believe that this is the first time that Boeing had an aircraft grounded in this way. I believe it was 3 months for Boeing to have an FAA approved fix. Incidentally the 'fix' was a heavy duty sheet metal box around the battery, with a vent to outside the aircraft. I suppose time will tell how reliable a fix this is. Finally there have been issues with debris being left in fuel tanks, metal shavings in wire bundles, etc. Allegedly in aircraft delivered to customers.

737 MAX - A half-baked software bodge has left hundreds dead and all these aircraft grounded worldwide. This is the second time Boeing had a commercial aircraft grounded worldwide with no end in sight. As with the 787 there are issues with debris being found in "complete" aircraft, with foreign object material being found in fuel tanks AFTER the aircraft has left assembly and passed inspection.

KC-46A (Air Force Refueling Tanker) - Years late, over a $1B over budget. Egg on face issues like not having the (required) FAA approval for fuel pods and drogue system. Repeated issues where Air Force refused delivery because of... debris in fuel tanks.

Starliner Crew Capsule - multiple critical software errors that meant the capsule never docked with the ISS and was nearly lost.

There are some common threads here. Bad software for 737 MAX and Dreamliner. Foreign object material ending up in wings and fuel tanks over and over.

Finally there is good reading to be had about quality issues in assembly, parts being rejected as defective and then "disappearing." Whistleblowers are reporting that the "disappeared" defective parts such as tail assemblies are ending up on aircraft and being delivered to customers. It seems there is pressure from management to sacrifice safety for profit, pressure to approve designs (thanks to some really good lobbying, Boeing essentially gets to approve its own designs with minimal FAA oversight), pressure to keep you mouth shut about safety concerns (and retaliation if you don't).

These are not signs of a healthy company. By now I think that Boeing has slid into "all-around shitty." The above is my best recollection of news stories from years of watching Boeing, if I have made a mistake then I am happy for any corrections. Let me know if you would like links to any of the particular stories or believe that a [citation needed] is in order.

Your post seems to imply that a bad product negates the respect earned by leading an industry, nay, multiple industries, for several decades.

Do you really truly think that just because the MAX is a POS, that everything that comes out of Boeing can be evaluated under that same lens? Surely you aren't so blind to the reality that engineers do occasionally produce quality work.

To your credit, I wouldn't fly myself or my family in a MAX, but I'm not uneasy about getting into a Boeing aircraft across the board, at the same time. That'd just be irrational.

Perhaps you could clarify your stance, as you may know more than your post reveals.

> Do you really truly think that just because the MAX is a POS, that everything that comes out of Boeing can be evaluated under that same lens?

No I do not. I still wouldn't ever refer to Boeing as well-respected nowadays. Granted, it may be irrational quirk of mine.

To clarify, do I respect Boeing? Yes. But I would not make a post on the Internet and write out "well-respected". I understand Boeing's cultural shift from being an engineering-first company and its MAX fiasco would not warrant "well-respected" in many people's eyes nowadays.

Was Boeing well-respected in the past? Yes. Is Boeing well-respected nowadays? Yes. But to deliberately write it out to me feels like trolling and stoking fire. You surely must understand that a lot of people lost a bit of respect for Boeing in recent years.

I can understand why it may have sparked those feelings because of the way I wrote it.

I'm a pretty forgiving person, I've spent some time in and around rehab and I've learned personally the value there is in giving people a chance they don't deserve. I know how hard some of the engineers at any big industro-* corp are working, and I choose to have hope that those hard-working folks' ideas and values are represented in the product line that they serve on.

I didn't mean to say that recent events should be scrutinized any less critically, and I disagree with that, especially in the case of passenger aircraft, the utmost care should be taken.

I've read a little bit about 737 MAX, and it strikes me as one of those things where too many boardroom cowboys got to run off and make deals, and the brains and engineers and designers were left with the scraps of an impossible task.

I don't know. I just have a soft spot because I can imagine what it's like for a lot of those guys, going to work and doing their best, and the project is so large that there's just not much any single person can do when it all begins to fall apart at the seams and catch fire. I feel bad that all those people have this terrible mark on them because of the product being a huge, public, terrible failure.

Boeing has done incredible things for the field of aviation, aerospace, maritime, rescue, you name it, they've made a flying vehicle to do it. That can't be washed away because a bunch of guys fucked it up, because it wasn't the people that worked the hardest. So, while I perceive that critically, I respect the name Boeing for what it's given the world in the past.

Anyhow, I wasn't trying to start anything by writing that, I guess it was just part of my thought process that didn't get edited into words very well.

Thanks for your perspective.

They are a respected company with many respected products, despite your personal feelings towards them. They did screw up big time with the 737 MAX, but they still have a huge portfolio of well engineered products and will surely launch more well respected products in the future.

In my opinion, a big screw up at least warrants that you lose respect, at least temporarily.

They can regain respect by building new good products. Or by admitting mistakes, surely not by laying blame on the pilots.

I am less forgiving. If you want to forgive them, that's your choice.

> they still have a huge portfolio of well engineered products

Mostly obtained by acquisitions.

In current production only the 737, 747, 777 and 787 and T-7 originate solely from Boeing.