I'm going to start off with saying I am a certificated aircraft mechanic, and I've been exercising my privileges as such for several years on both passenger and cargo aircraft for several airframes.
This situation is actually a VERY big deal and it is going to be VERY expensive and time consuming to fix.
When a part is sold or repaired by a manufacturer, it comes with an airworthiness certificate. In the US, this is FAA form 8130-3. It not only certifies that the part conforms to specifications; but it shows who certified it, who tested it, what specs it meets, and the history of the part. Both the airline purchasing the part and the mechanic installing the part need this document to legally repair the aircraft.
There could be a variety of problems with receiving fake parts that slip by SUP inspections (Suspected Unapproved Parts), and these are both legal and safety problems. A fake serial number means you don't know the true history of the part. It could have been pulled from an abandoned aircraft from a third world country, and even though it passed a bench test, it could be a ticking time bomb. It could be a part in exceedence of service hours, but the paperwork that came with it says it's freshly overhauled.
It could just plain not meet specifications. Premature failure is a big deal. Especially when the list of things that can be broken on a plane (MEL / Missing Equipment List) and still be safe for flight depend on a rated level of reliability. As an example, an aircraft can operate with a certain number of brakes not working for a limited period of time (such as up to two inoperative, no more than one per pair, for no longer than 10 days or 10 flight cycles). This assumes that all of your other brakes aren't going to prematurely, simultaneously fail before that time limit is up.
This article specified that these are engine parts, which adds a whole other level of risk to flight safety. The CFM56 from this article can be rated for ETOPS 180, which stands for Extended Operations up to 180 minutes.
Normally, twin-engine aircraft are required to remain with 60 minutes of a suitable airport in the event of an emergency. This often limits what routes certain aircraft can take. ETOPS allows certain aircraft to go farther than the 60-minute rule (in this case, up to 180 minutes), which is a huge deal in terms of flight time, efficiency, and simply whether or not they can fly internationally. To maintain ETOPS rating, the aircraft has to meet stricter specifications. These can range anywhere from parts with tighter tolerances, to things like larger oxygen and fire-extinguishing bottles. They also need to be able to start their APU in flight for a source of electricity in the event they lose an engine.
The airline is also limited on the number of in-flight shutdowns they can have. This number is intentionally very low. If the airline as a whole exceeds this number, their fleet-wide ETOPS rating will be revoked.
Parts have to be specifically rated for ETOPS to be installed on an aircraft flying ETOPS routes. Bad parts make this a huge risk. An in-flight shutdown is a very dangerous situation, and bad parts dramatically increase the risk of that becoming a dual engine failure while that plane spends 3 hrs diverting to the closest airport.
Going forward, there is no good way to check if the parts sold actually meet specs until they're disassembled and checked. Directives from the FAA will be issued. Inspections will be performed. Airplanes will be grounded and rectified. The manufacturer might be able to provide a list of parts that need to be recalled, but more than likely EVERY part they issued will be pulled. They may also have their repair station and manufacturing certificate from GE revoked. Even if they don't lose their certification, most of the airlines will avoid them now.
To address the points you made in your comment, lefixxx, false documents mean bad parts. These parts absolutely DO pose a safety risk. They very likely ARE out of spec, timed out, or simply not rated for what the papers say. Even if the part is tested and meets specs, the history of that part is lost. It will need to be overhauled and made "new" again in order to be airworthy.
All of the regulations and strict document control requirements we follow have all been written in blood. People HAVE died because of things like this in the past, and it's our mission to keep it from ever happening again.
Can I just say, thank you for the extremely informative post.
This is the kind of comment that reddit was valuable for - being able to jump on a thread about find an obscure expert in pretty much any niche field. Lemmy hasn't really reached a sufficiently large userbase, so seeing a post of this is like a breath of fresh air.
I don’t think you quite understand the level of rigor that these components are manufactured with. If the documents are not provided, or if they’re counterfeited, the parts are assumed to be out of spec. The precision required for these things, as well as the integrity analysis done after they’re completed, are absolutely critical, and can make the difference between 1000 and 10000 hours MTBF on something like a compressor stage.
I agree that the parts are probably out of spec and assuming they are, is definitely the way to go, but I am dissapointed by the lack of precision in articles like that.
This is the first (maybe the second) link in the chain of misinformation. Every time this article will get reposted, rewritten or reblogged the inaccuracies will move the baseline for the next one.
Fair, though keep in mind the intended audience is the average layperson, which means the bar is set pretty low in terms of the technical nuance of the writing.
Exactly. Try to explain that a .05 difference in carbon content can result in a substantial increase/decrease in tensile strength - eyes glaze over. When the right engine blows eyes unglaze.
That, or how quality analysis can detect things like improper metal crystal formation and other molecular-level defects that impact material integrity and suitability, amongst many other things.
But it is inevitable that if they’re not testing parts, ornwhatever, that parts not meeting standards will come into use.
Which means you’re wrong about this only potentially being a safety risk. It IS a safety risk. Period.
They’re intentionally falsifying documents to save a buck. They should be fucked out of business and the idiots who thought it was a good idea thrown in jail. (That would likely be the Execs.)
There is no reason to fake the certification documents unless you're not following the required standards.
Why would a manufacturer go through all the effort and expense to make parts at the required standards, with hugely expensive manufacturing, only to take on a huge risk to save a negligible amount on the paperwork? That is a horrible business decision.
The paperwork cost isn't negligible at all. For example a company I used to work for had to replace a simple O-ring that failed. It's an old part and quite rare these days and cost $800 to replace. You could buy a functionally equivalent (likely better) uncertified part for about 5 cents. That is why uncertified parts are such a problem, because certified ones are so incredibly expensive. Plenty of companies would love to step in and buy a few thousand O rings and sell them for $400 and a few are willing to forge a paper trail to make it happen. It's a problem that I don't really think will be ever totally solved without making certification too easy and potentially sacrificing safety by having bad certified parts.
If you spent $800 on an oring and it fails and the plane goes down, the manufacturer is liable. If you spent $0.05 on the oring and the plane goes down, you're liable. Like you said, paperwork isn't cheap. Because its basically liability insurance. If you made the oring, would you accept liability for $0.05?
The problem isn't the manufacturer or the operator, it's the middleman looking to make a profit on the the difference. In any case $800 is an absolutely ridiculous price point regardless of liability. I don't know where the fair price point is but not even close to that. Liability isn't the primary driver for the cost anyway, it's difficulty of certification. Getting any part certified runs from high 5 figures to many millions of dollars and these are all extremely low volume parts. Boeing has only made around 11,000 737s since 1967. The plane I'm working with now only has around ~250 built since 2015 and is quite successful. For comparison Toyota produces about 20 cars per minute. When you need to pay back certification costs and turn even a modest profit on such low volume you need to charge a ton for each part.
To be clear I am absolutely not in support of non certified parts, it's just a big problem in the industry and for rather obvious reasons.
these COULD pose a huge safety risk. Until the parts are tested it is unclear if they are actually bad.
this is a badly written article
The article is correct. The safety risk is that the parts COULD be dangerous to use. Whether the parts are actually defective or not is irrelevant because they don’t know; that’s what makes them a risk.
And importantly, it wasn’t safe for a very long time, specifically because these rules and regs weren’t yet written. A TON of flight safety laws, rules, and guidelines have been written in direct response to accidents that have destroyed planes and killed everyone on them, so it’s actually quite accurate to say those rules are written in blood.
If any of the paperwork is missing or falsified the part is scrap. When we buy material it comes with certified reports on the alloy's component elements.
Inconel is often used around engines for heat resistance. If it has too much of an element that changes at what temperature it becomes ductile you could lose some very important components or systems.
Steel doped with sulfur raises its embrittlement temperature.
They'll be tested to sort out the urgency of the corrective action, but those parts are scrap. Also, someone might be going to prison.
Is it insane to play Russian roulette? There's a good chance nothing will happen if you pull that trigger, right?
By definition, risk means there is no guarantee of a specific outcome. There is no risk of falling if you jump off a cliff (without special aids) - you just fall. Smoking increases your risk of cancer. Bob Hope lived to 100, apparently cancer-free, while smoking. Neither of these statements are untrue, he just didn't suffer the results those risks indicated. While that's good for him, it's not the attitude I want taken with aircraft parts.
Most metal parts testing is destructive. I.e., once you test the parts, they are destroyed and you can't use them anymore. That's why the trust I certificates is so important. They certify that metal from the same batch passed those tests. That's why it's a huge safety risk if the certs are fake, there's no guarantee that the metal can meet the requirements, and no way to test without breaking the parts.