3D printing parts is FAA approved?
I'm not sure Gloucestershire is under FAA jurisdiction.
It was purchased at a U.S. airshow
A Cozy Mk IV light aircraft crashed after 3D-printed part was weakened by heat
181–190 of 223 posts
Re: A Cozy Mk IV light aircraft crashed after 3D-printed part was weakened by heat
#182It's important to note the plane is a Cozy Mk IV, which is an experimental light aircraft that is built at home out of foam and fiberglass by following instructions you get online. The design is very good, and hundreds have been flown over the last ~35 years, but Cozy pilots are the aviation equivalent of people who run Arch Linux as their daily driver; many of them are tweaking their aircraft with some frequency. Th…
I think this needs to be added to the urban dictionary "Cozy pilots are the aviation equivalent of people who run Arch Linux as their daily driver"
Re: A Cozy Mk IV light aircraft crashed after 3D-printed part was weakened by heat
#183Earlier quoted context omitted.
Figured it was experimental; no A&P who cared about his future would install a 3D printed part on a certified aircraft.
Actually, I think all of the jet engine manufacturers these days are using 3d printers for some of their parts? Although you usually find the press releases talking about this using the term "additive manufacturing" instead. See, e.g., this press release from 2018 about a notable jet engine manufacturer using 3d printing: https://www.geaerospace.com/news/articles/manufacturing/manu... (Although note that these are no…
Getting it certified for flight is insanely difficult because one of the challenges of AM parts reproducibility.
Re: A Cozy Mk IV light aircraft crashed after 3D-printed part was weakened by heat
#184Earlier quoted context omitted.
Actually, I think all of the jet engine manufacturers these days are using 3d printers for some of their parts? Although you usually find the press releases talking about this using the term "additive manufacturing" instead. See, e.g., this press release from 2018 about a notable jet engine manufacturer using 3d printing: https://www.geaerospace.com/news/articles/manufacturing/manu... (Although note that these are no…
It's not the "3D printed" aspect of the part that's driving the failure, it's that it's made out of thermoplastic. An injection molded part in this situation[1] would likely have failed in the same way. [1] It's not clear what the source of the heat was or where this was in the motor enclosure. But yeah, one needs to be careful with structural plastic near running engines!
Thermoplastic is the problem here. There are plenty of thermoset and other kinds of plastics that handle heat well and don’t soften with heat in normal ranges. 3d printed thermoplastics typically need to be liquid at <300 C so the glass transition usually is closer to 200 or even less. Definitely not suitable for the engine bay.
Re: A Cozy Mk IV light aircraft crashed after 3D-printed part was weakened by heat
#185Earlier quoted context omitted.
3D printing is to mechanical engineering what vibe coding is to computer science. With the rise of accessible 3D printers that can print engineering materials, there are a lot of people who try to create functional parts without any engineering background. Loading conditions, material properties, failure modes, and fatigue cycling are all important but invisible engineering steps that must be taken for a part to func…
Ehh. Everything you need to consider is really not that much when it comes to most typical consumer 3d printing projects. Mostly because they are usually about stuff like "fixing a broken tashcan". The engineers who made that bullshit plastic part that broke after a year probably knew all about area moment of inertia, but that doesn't mean I need to to print a replacement part that lasts longer - or not, in which cas…
Hmm, I suppose the analogy could be interpreted as dismissive, which is not my intent.
I think both vibe coding and 3D printing are wonderful things. Lowering the barrier to entry and increasing technology accessibility allows those without formal training to create incredibly capable things that were previously difficult or not possible to do.
What I meant to specifically highlight is the 3D printing of functional parts that have some level of impact on safety, things that can lead to significant property damage, harm, or loss of life. Common examples include 3D printed car parts (so many) and load bearing components in all sorts of applications (bike mounts, TV mounts, brackets, I even saw a ceiling mounted pull-up bar once).
This isn't to say it can't or shouldn't be done. What I'm saying is that both on the digital side (files for personal use) and the production/sale side (selling finished parts), there is no guarantee of engineering due diligence. 3D printers enable low volume small businesses to exist, but it also means that, purposefully or not, their size means they can go quite a while without running into safety regulations and standards meant to keep people safe.
Re: A Cozy Mk IV light aircraft crashed after 3D-printed part was weakened by heat
#186It's important to note the plane is a Cozy Mk IV, which is an experimental light aircraft that is built at home out of foam and fiberglass by following instructions you get online. The design is very good, and hundreds have been flown over the last ~35 years, but Cozy pilots are the aviation equivalent of people who run Arch Linux as their daily driver; many of them are tweaking their aircraft with some frequency. Th…
Do we know whether the part was made out of spec, or whether the spec specified inappropriate materials?
I don't know if it is the same in the UK as it is in the US, but the appeal of experimental aviation (every Cozy is experimental) is that there are no specs or requirements around parts like this.
If you want to slap 15 weed-wacker engines to a wing you made from styrofoam and call it an airplane, the FAA will not stop you.
I'm oversimplifying, a bit, but less than non-pilots might think.
In other words, the engine maker probably has some thoughts about how that piece should be made, but the FAA would have no problem with you installing it on an experimental.
Re: A Cozy Mk IV light aircraft crashed after 3D-printed part was weakened by heat
#187Earlier quoted context omitted.
Manufacturers who use 3D printing use specialized 3D printers, not the same thing that hobbyists use. They also handle all of the testing of parts to ensure they meet the design spec and they have the equipment to validate each printed part to ensure it doesn't have any major defects.
You can see the layer lines in the part. WTF? I don’t build aircraft parts. But I sure as hell wont use thermoplastics in this situation. I don’t even 3D print parts for mildly hot environments where failure is just annoyance. Whoever built this should be charged.
> Whoever built this should be charged.
This is an uncertified experimental aircraft. At least in the US, it is up to the operator of an experimental to ensure that parts are fit for purpose.
Re: A Cozy Mk IV light aircraft crashed after 3D-printed part was weakened by heat
#188This is the mechanical equivalent of vibe coding. 3D printing itself isn't exactly to blame but the negligence of the company that created and sold this part and omitted it's use from an inspection. Just because a part has the shape of an engineered part does not make it compatible, strong, safe, and fit for purpose. This part could have likely been fine if it used a different material such as Ultem.
> blame ... the negligence of the company that created and sold this part That should be so obvious that I wonder if it was DIY by the pilot.
> That should be so obvious that I wonder if it was DIY by the pilot.
I don't know how the regulatory environment is in the UK for experimental craft (this is considered to be "experimental" category in the US and Canada), but yes, the idea behind an experimental is that everything is DIY.
I have an experimental, and I can do close to anything I want. What I can't do is complain when my plane crashes because I installed a part that isn't fit for duty. I, as the owner and operator, am the one that signs off on the airworthiness of the plane.
E.G. If I install a Cessna part on my plane, and that is the cause of a crash, that is my fault from the point of view of the FAA.
There may be legal considerations outside of airworthiness and flight rules, but as far as the FAA is concerned (or would be if this had happened in the US), the manufacturer of a part is off the hook once the thing is installed on an experimental.
Re: A Cozy Mk IV light aircraft crashed after 3D-printed part was weakened by heat
#189Earlier quoted context omitted.
Also, strictly as a combo 3D-printing and engine enthusiast: Never with a GUN to my head would I install 3D printed parts in a CAR engine, let alone in an aircraft engine. This is spectacularly poor judgement on the part of the owner.
> Never with a GUN to my head would I install 3D printed parts in a CAR engine, let alone in an aircraft engine. The fabrication technology doesn't matter. The qualification process, on the other hand ... This is the primary reason why I never got a pilot's license. I suspect I would spend far too much time making sure the maintenance was up to standard and far too little actually enjoying flying.
You should be thrilled to know that any plane you will learn to fly in typically has full maintenance records for the entire life of the plane, including who did the work, their FAA certificate number, and all of the paperwork for any parts that were involved in the repair.
The shortcut is to ask the mechanic to come for a test flight after repairs. The place I learned to fly was owned by a mechanic, and the daughter ran the flight school. Given that the daughter might be test flying the mechanic's work, I trusted him to keep his planes in good shape.
Re: A Cozy Mk IV light aircraft crashed after 3D-printed part was weakened by heat
#1903D printing parts is FAA approved?
This occured in the UK, so not really relevant to the FAA.
In the US though, yes, the FAA would not have a problem with this. This plane would be registered as experimental, meaning you can install unapproved parts. It does have to be inspected, but that can be done by the builder (not the designer, just the guy who built that particular example), or an airplane mechanic.
I know quite a few experimentals with 3d printed parts (including my own). I don't know any where they are installed in a place where failure would result in a crash. Typically I see them used as convenience stuff, in my case I am using a 3d printed catch to hold my upward opening door while I load the plane. If it breaks in flight, I wouldn't even know. If it breaks on the ground, the door will close.