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Here's a fun true story.. Aircraft do not have a singular unique identifier that is time invariant. While it is true that aircraft have serial numbers issued
by sixdimensional 1y ago
Here's a fun true story..
Aircraft do not have a singular unique identifier that is time invariant.
While it is true that aircraft have serial numbers issued to their airframe, by itself, aircraft serial numbers are not unique.
The only unique identifier for an aircraft across its lifecycle from production to end of life is a combination of the manufacturer, make and serial number.
I know this because I am on (for better or worse) the patent that involves defining that as a unique identifier for aircraft.
The combination of ICAO aircraft type designator + serial number approximately is the most permanent identifier for an airframe - and even then - if an airframe is modified significantly enough that it no longer is the previous type - even then this identifier can change.
Personally, it boggled my mind that something as big as an aircraft did not have a simple time invariant unique identifier.
P.S. For those who might ask - aircraft registration numbers are like license plates, so they change - tail numbers can be ambiguous and misinterpreted depending on what is painted on the aircraft where, and ICAO 24-bit aircraft addresses are tied to ADS-B transponder boxes, which technically can be moved and reprogrammed between aircraft also.
- Xevion 1y agoAircraft of Theseus
- sixdimensional 1y agoExactly!
- Dylan16807 1y agoThe full Theseus treatment would need you to take [part of] the airframe that first plane discarded, then recertify it for use under its original serial number. Is that allowed?
- travisjungroth 1y agoThe way the Aircraft of Theseus is generally resolved is there’s a piece of metal called the “data plate”. This is the airplane as far as the FAA is concerned. I’ve been in a vintage biplane that was completely rebuilt from the data plate up. I think they got it for $40k. It was worth it because without that, a home built airplane would have an experimental certificate and you couldn’t sell rides in it.
- throwaway290 1y agoBut does the data plate have an ID?
- travisjungroth 1y agoYes, but it’s not necessarily unique like a VIN.
- dotancohen 1y agoDoes the data plate not limit the scope of what can be built around it? In other words had Virgin Galactic built the VSS Enterprise around the data plate of a Cessna 172, would it then no longer have been an experimental aircraft?
- ovi256 1y agoIt does limit, but I suspect a lot less for the rebuilt from ground up biplane, than for a certified for airline service aircraft (a commercial airliner).
- travisjungroth 1y agoThe airplane has to match the data plate. Otherwise, it will fail inspections because of all those unauthorized modifications.
- deleted 1y ago[deleted]
- ortusdux 1y agoEven runway IDs change over time: https://en.m.wikipedia.org/wiki/Runway#:~:text=Runway%20designations%20may%20be%20changed,years%2C%20most%20recently%20in%202009. https://en.m.wikipedia.org/wiki/Runway#:~:text=Runway%20desi...
- justsid 1y agoThose aren’t IDs though
- SonOfaNerd 1y agoThose are runway numbers. Which are the direction the runway is facing.
- pyuser583 1y agoThe “real” unique identifier is such a common problem. And the solution is almost always “model, make, and serial number.” Plus year of production if necessary. I’ve seen programmers attempt deduplicate humans by language spoken.
- oflebbe 1y agoI know about systems who had two types of serial numbers which ought to be the same, but weren‘t because they had been programmed at different eol stages, when daylight savings time kicked in. One of the system run in utc the other in local time. Date was part of the serial.
- sixdimensional 1y agoParallel production lines with overlapping sequences also cause this, especially in aerospace- it is widely known that Airbus does it, for example.
- specialist 1y agoVery interesting thread. Noob me would have guessed the "source of truth" would be whatever identifier(s) is recorded by the insurance company. Or maybe the service and maintenance agreements. Failing that, I would have guessed some kind of (natural) compound key derived from the transfer(s) of ownership (Airplane Purchase Agreement? Bill of Sale?) noting the unique major components like airframe, interior, and engines? And maybe wings? Sounds like a fun problem. Thanks for sharing.
- fho 1y agoHow does "model, make and serial number" translate to humans? (No racist intentions here, but you bring up both points and I thought that to be interesting)
- godelski 1y agoJohnson Smith The son of John who is a smith I'm only joking a little. Funny thing, surnames aren't actually that old for Europeans. Most of history there'd be maybe two people with the same name. They solved it back then very much the same way we solve it now. https://en.wikipedia.org/wiki/Category:Occupational_surnames https://en.wikipedia.org/wiki/Category:Occupational_surnames https://en.wikipedia.org/wiki/Patronymic https://en.wikipedia.org/wiki/Patronymic
- rootsudo 1y agoI would also say engine too.
- genocidicbunny 1y agoEngines are actually changed fairly frequently because they're a wear component on most airplanes. They are also sometimes updated to a newer version or even an entirely different manufacturer. And often it's faster and cheaper to swap in a new engine that's ready to go rather than wait for the one that's attached to be overhauled, so the same engine might see service on multiple airframes.
- dingaling 1y ago> Engines are actually changed fairly frequently A modern turbofan can run for 20,000+ hours on-wing before removal for overhaul. That's longer than many car engines last in total.
- extraduder_ire 1y agoMost cars don't operate for >12 hours a day every day. Last time I randomly checked the flight history of a Ryanair 737 on flightradar24, it had spent over 18 and a half of the previous 24 hours airborne.
- justsid 1y agoSame with trains. If they don’t run, they start to lose a lot of money for the operator really fast.
- rootsudo 1y agoThats why it should be tracked.
- NoboruWataya 1y agoEngines are treated as their own thing separate to the airframe, with their own serial numbers.
- Too 1y ago> combination of the manufacturer, make and serial number. > patent that involves defining that as a unique identifier for aircraft. Now i got mighty curious what makes this novel enough to be a patent.
- jajko 1y agoMaybe its right-click level of patent.
- tux3 1y agoYou burrow this simple idea in pages and pages of obfuscated tedium, and that's good enough that everyone is happy. Patent office gets their fee, lawyers get paid, company can say it has a supercharged patented innovation.
- amelius 1y agoIt's a unique identifier but now "not on a computer".
- Tostino 1y agoI was wondering the same thing. I've had to derive unique identifiers from hundreds of different data sets over the years. What makes it special when it's a plane?
- brewdad 1y ago>> it’s on a plane. Exactly this. The domain space and a couple of good lawyers makes it patentable today.
- dmd 1y agoGo work at a big company. The patent lawyers come around and ask what you've been working on, and a month or two later, your name's on 10 patents, none of which make any sense whatsoever. If you're very lucky you might get a dollar bill for each.
- sixdimensional 1y ago
- genocidicbunny 1y ago> Personally, it boggled my mind that something as big as an aircraft did not have a simple time invariant unique identifier. It boggles my mind that despite not having some sort of universal system things work as well as they do. Aviation grew up relatively insular, and each country that had any sort of aircraft manufacturing did things their own way until fairly recently. Arguably, the first half of the history of aviation is a kind of free-for-all. The fact that we now have a globalized airline industry that mostly follows some kind of standards is the mind-blowing part to me. And I suspect if we weren't mostly down to a dozen or so manufacturers for the vast majority of airliners, even that wouldn't be the case.
- amelius 1y agoYeah but at some point countries started buying larger planes from only one or two manufacturers. At that point the manufacturers could standardize things.
- sixdimensional 1y agoAgreed!
- frereubu 1y agoReminds me of the ship of Theseus: https://en.wikipedia.org/wiki/Ship_of_Theseus https://en.wikipedia.org/wiki/Ship_of_Theseus
- Aardwolf 1y ago> combination of the manufacturer, make and serial number What if a new aircraft were made 50/50 from the parts of two older aircraft
- deleted 1y ago[deleted]
- dmd 1y agoIt would depend on which side got the data plate.
- potato3732842 1y agoI don't think it even matters. If what you're doing doesn't piss off any potential enforcers you're good to go. If whatever you're doing does then you're screwed (or will be tied up in court and paying tons of lawyers fees) regardless.
- OptionOfT 1y agoA unique identifier would've helped: https://viewfromthewing.com/american-airlines-flew-passengers-on-the-wrong-plane-for-8-hours-too-big-to-land-diverted-to-rome/ https://viewfromthewing.com/american-airlines-flew-passenger... Almost comical that it happened 1 day after this was posted.