Yes, things like rulers and gauges are tested. The schedule depends on the use case and frequency of use. For relatively light lab duty stuff, rulers and gauges were checked 1-2 times a year. Things that are used more frequency or more aggressively are checked more often.
They're cheap. Shops that care have them on a replacement schedule.
Put is this way one time I found a set of hex torque drivers with cal stickers on them at a surplus place. So when I say everything I do mean everything. So yeah a feeler gauge should be traceable.
This idea again. I don't know why people are saying this. It's not true. Aviation you're allowed to use any tool you want unless the workshop manual says to use a specific tool.
OEM calibration certs are useless to an aviation company because it's someone else promising accuracy that could see you thrown in jail if it's wrong. Before tooling is used the first time it will be calibrated. Then calibrated again at set intervals.
>hex torque drivers with cal stickers
It's most likely the part had stickers so it was in their system for visual inspection for good condition. I have a pair of lockwire pliers that were pulled from the shop floor due to them being indicated worn during a visual inspection. I still have them 7 years later and they're still the sharpest pliers I own.
As for the traceability from birth, this applies to parts that go on the aircraft not tooling. Tooling traceability you need to know what tool was used if it's required to be calibrated. ie torque wrenches.
If the feeler gauge doesn’t slip in with minimal force, then that tells you the gaps is smaller than the gauge.
The numbers of sets of comically bent out of shape feeler gauges I've encountered in my life demonstrates that there's a bunch of folks out there who don't understand how they're supposed to be used. As in "maybe if I just push harder this'll fit" :)
When I was young, it was guaranteed that a lifter would let loose just before you picked up your date on Saturday night if you had not “run the valves” in the past month.
Clack-clack-clack-clack-...
Date: Why does your car sound like it’s broken?
Me: <mutter>
In my experience, I think you're probably right, it does seem like people may take them as "more accurate."
These planes have regular maintenance checks and diagnostics to help identify issues before they become catastrophic failures. This whole thing is likely a normal maintenance issue, maybe unexpected due to the unusual nature of the scenario they face with so many idle jets, but not something that would have escaped their servicing routines. The system flagged a problem and now they can address it. If for some reason their diagnostics were not set up to detect this sort of issue then you have a problem.
And it’s not often the wings fall off, but the tail does, or sometimes a huge hole opens in the “skin” of the airframe.
Example: Aloha Airlines Flight 243
The non-precise way you've already heard about, sheet of paper, check for dragging.
The better (more precise) way, is using a magnetic base micrometer attached to your extruder head. You can then watch the bed run-out in real time; if your 3d printer supports many configurable sections across the bed ( I know Prusa style cartesian units mostly all support quadrants) you can record the run out everywhere across the plane without any more physical work than watching the gauge and recording the results.
P.S. be careful using both the micrometer and the feeler gauges on a 3d printer bed. Most work plates now-a-days are using PEI coatings that'll scrape off easily with metal-on-metal contact.
Yeah, you're correct, it's a glass bed so I use it to do the 4 corners (every few months) and then use a BL touch to do a 3x3 grid on top of it.
It seems like we really like to push the limits when it comes to shooting each other.
Weapons can be used for defensive purposes. There's nothing inherently wrong with them, only how people use them.
> parts you couldn't use parts from one rifle on another without a smith
You cannot swap bolts in the field on most rifles. At minimum, you require a go/no go gauge. The tolerances on modern firearms are very precise.
Believe it or not, that's actually a lot of the idea that drives commercial aviation design.
Or used to anyway.
> A complex system that works is invariably found to have evolved from a simple system that worked. A complex system designed from scratch never works and cannot be patched up to make it work. You have to start over, beginning with a working simple system. - John Gall
Despite what we see on the web more and more, this principle applies to code too.
It shouldn't be about stacking up layers of complexity for no good reason.
His example was designing brackets for a Indonesian construction company that was using locally sourced tropical softwoods for constructing buildings. The brackets were designed to be made with 'steel' and the tolerances were compatible with a hungover guy running a drill press.