You're right, they do. And I'm certainly no expert, but I have a more difficult time imagining a tire coming off the wheel intact without some catastrophic "blowout" impeding it's ability to smoothly roll than I do imagining a whole wheel coming off.
Leak, low pressure becomes no pressure, various lateral forces encouraging the tire to fold this way and that under mass, and soon enough the tire alone escapes its tormentor (because it’s being bent and pushed in ways similar to those that originally encouraged it to pop onto the wheel) and scurries away toward an unsuspecting fence.
Americans commonly use "tyre" and "wheel" interchangeably. Drives me nuts especially in motorsports where the distinction is important. But it is what it is. This was a case of a wheel coming off.
Not sure if I missed your joke. But this is probably a joke based on the spelling of the word being British. So Americans use tires and the British use tyres.
I wasn't joking, I'm not going to use the American spelling just because I'm talking about how Americans use the word. They really do use "wheel" and "tyre" interchangeably.
I'm an American, and I disagree, mostly. I've never heard someone say a "flat wheel"; it's always flat tire. Also if an American says a wheel came off when they mean a tire, they misspoke/misunderstand what they are talking about. There are plenty of Americans that know next to nothing about their vehicle despite it usually being the most expensive or second most expensive thing they own.
Disclaimer: Midwest USA here, can't speak for other parts of the US.
I can't think of anyone other than the most archetypal ditz (think, 'Friends' character, Phoebe) who would conflate the idea of the rubber part that touches the ground with the metal or other hard material the first term is mounted on. (Naming abstractions removed for clarity.)
Now, every issue with a Boeing plane will be noticed, reported on and magnified. I'm not saying this is necessarily bad as there actually do seem to be some significant issues at Boeing. Hopefully, the result is an intense shakeup resulting in increased focus on quality.
There were plenty of rumblings about Boeing's poor quality control after the MCAS issues. Didn't seem to change much. But then again, maybe this is the straw that breaks the camel's back in terms of PR.
Maybe different problem here: while MCAS was an engineering problem, door was an assembly problem, here it would more likely be a maintenance problem (757s have been built years ago), which is on the airline or not directly Boeing?
The last 757 flew away from Boeing in 2004. It's surely the case that the landing gear issue that happened today has little or nothing to do with Boeing's quality control and everything to do with airline maintenance actions/responsibility.
Here is a list of the top ten causes of death in the US [1]. You will have a much better chance of reducing your risk of dying by giving up drinking and eating fatty foods than by giving up flying on a Boeing aircraft.
1. This is misleading because the number of people flying on airplane is significantly lower than those who have a chance for heart disease because they have a heartbeat.
2. Not flying on Boeing aircraft is much, much easier to do than avoiding heart disease.
I think this has been happening since the Ethiopian Airlines incident. Individuals should be extremely careful about using the news as a reliable way of measuring personal risk.
I was reacting to the suggestion that people will only react to this out of misplaced "confirmation bias." Your statement was qualified as "it's not _necessarily_ bad."
The suggestion is that a negative or useless human emotion may, in this case, be incidentally useful.
My suggestion is that it is not at all useless or negative, and due to the safety factors involved, this is more due to survival bias than confirmation bias.
I sort of felt you were punching down into the public crowd gathered around this issue, and I took some umbrage with that.
All airliners occasionally have problems with wheels and/or tires. And occasionally have cracked window glass. And occasionally have engine failures. And occasionally have pressurization problems, Read avherald.com for a few days and you'll see that it happens to Airbus, Boeing, Embraer, Bombardier, and others. And with the number of flights worldwide, some kind of problem serious enough to cause a return to the aiport or diverting to an alternate happens almost every day.
Boeing has some serious questions to answer about their engineering and QA processes. But attributing random normal problems to that just confuses the issue.
Of course, these are "normal problems" that shouldn't happen and need to be investigated, but it's not quite "the front fell off": https://youtu.be/3m5qxZm_JqM
All that grandparent comment is saying is that this specific news story is a nothing burger, not that we should ignore other, bigger issues. In fact, they're saying that mentioning small issues like this is a red herring and a distraction. Presumably they agree that the recent Alaska Airlines door plug mishap and the total losses you mentioned are important.
Had a physics teacher in highschool, worked on a submarine. Told me that with government equipment like submarines, workers replace parts based on dates regardless of the wear and tear of the part. "If this screw is supposed to last 10 years, we're ordered to replace it in 7 years regardless of the condition."
With for profit companies, they'd try to push the parts to last 12 years instead of 10 by inspecting them and confirming they're still good.
Saving money this way isn't too big of a deal if you're McDonalds and it's an ice cream machine.
But if it's a for-profit airline it can turn into a problem.
It’s just a marketing term. Most predictive maintenance models are ML or statistical learning models and have a great track record. Some call it AI to sound hip (you can any ML model AI these days) but it’s probably just a standard model from reliability engineering.
It’s called predictive maintenance and it is the norm in many critical industries. Replacing equipment every fixed number of X years (no matter what the condition of the equipment is) is wasteful, costly disruptive and does not actually guarantee better reliability. (although it makes people feel better).
Most predictive maintenance is done with data — updated sensor data processed through a mathematical model derived from principles from reliability engineering. In a sense it’s actually more realistic than the X years model (which is a once off number derived from some reliability model too but doesn’t have the benefit of being updated with real data — it’s usually an overly conservative number)
Flatcircle's point wasn't really predictive maintenance vs. fixed lifetime, it was about government using conservative design margins vs for-profit industry's riskier design margins.
Predictive maintenance lets you achieve a better cost-vs-risk curve, but the organization still needs to select a point somewhere along that curve.
The other thing replacing the part can do (but not always) is guarantee you still have a source for those parts in the future. That's important for the military that might need to make more without much notice.
This happens from time to time for all aircraft models. It's why you should never be in the direct path of an aircraft taking off if you're plane spotting.
Remember when every train derailment was 100% evidence that the USA was a failed state like Ancient Rome? That period lasted for a few months, I can’t wait till this one dies the same death.
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