8 ms·

Falsehoods programmers believe about aviation

• AlienRobot 1y ago
  >Airports never move I can imagine them going "I had a perfect database schema that covered every edge case, and then..." with each bullet point.
  • icameron 1y ago
    Exactly I think that’s the point! Trying to make a strongly typed model, APIs and templates, etc… all while reality is making other plans
    • mcapodici 1y ago
      Thats when you ask the user to add another airport with the same name and -2 at the end. Add a "has moved" field!
      • sgarland 1y ago
        Now you have to specify whether or not it’s moved during queries (and what if it moves again?) There’s probably a more elegant way I’m not thinking of, but standard created_at and updated_at fields would work: if a given date is <= the move date, it’s the original airport, else the new one. Rinse and repeat if it moves again.
  • Marazan 1y ago
    The reassignment of a live IATA code between two airports was absolutely cluster fuck level. This had never happened before. Like, you don't even _change_ the IATA code of a live airport. To switch them was a huuuuuuuuuge assumption breaker for the industry.
    • bombcar 1y ago
      The biggest falsehood programmers believe is “a data restriction or programmer difficulty will have any affect on management decisions”.
• antonvs 1y ago
  [flagged]
  • tomhow 1y ago
    It's never possible to downvote submissions (only comments), but you can flag them if you think they're unfit for HN.
• amelius 1y ago
  Falsehoods managers force programmers to believe about X
• FabHK 1y ago
  As usual with these lists, they would much benefit from more in-depth explanation. This list at least deigns to link to examples for many of the claims (like a flight that leaves on time but arrives 40 hours late [1]), but doesn't explain what happened. Having said that, many of the links are very informative. For example the crater on Mars that has an ICAO airport code [2]: "On 19 April 2021, Ingenuity performed the first powered flight on Mars from Jezero, which received the commemorative ICAO airport code JZRO." [1] https://www.flightaware.com/live/flight/PDT5965/history/20250508/2224Z/KCHO/KCLT https://www.flightaware.com/live/flight/PDT5965/history/2025... [2] https://en.wikipedia.org/wiki/Jezero_(crater) https://en.wikipedia.org/wiki/Jezero_(crater)
  • freeone3000 1y ago
    This is often for boring reasons - the two week flight was a Google Balloon, the flight was delayed for 40 hours due to bad weather, ADS-B is set by the pilot and many pilots simply set it wrong, and so on.
• Titan2189 1y ago
  Great Summary of how messed up Airport Codes are by CGP Grey https://www.youtube.com/watch?v=jfOUVYQnuhw https://www.youtube.com/watch?v=jfOUVYQnuhw including (attempts at) a few in-depth reasons for why these quirks exists
• marcosdumay 1y ago
  > Flights take off and land at airports My impression is that every single older (pre-2010) computer system that manages the Brazilian aviation felt for that and fixed it in a hack. > Airports never move Also, Runways never move. Also, if runways move, they don't change direction. Also, if airport or runways move, there will exist some construction work before. I'd add "aircraft only land in runways" there too. And "ok, aircraft only land in runways and heliports".
  • phantomathkg 1y ago
    > My impression is that every single older (pre-2010) computer system that manages the Brazilian aviation felt for that and fixed it in a hack. Can you elaborate more?
    • khuey 1y ago
      A reference to Air France 447 perhaps?
    • genocidicbunny 1y ago
      I would assume it's somewhat speaking to the prevalence of many informal landing strips, and also that river landings are probably fairly common too. I'd have to imagine places like Alaska might also have to deal with that, especially if you have small local 'airlines' (which are probably just a handful of bush planes really) that operate from an actual registered airport.
      • cguess 1y ago
        Even the Eastern US has to deal with river and water landings all the time. You can book a scheduled flight from the East River right in-between Manhattan and Brooklyn to Marthas Vineyard, or the Hamptons or a number of other destinations. Not to mention those happen in the middle of arguably the most complex commercial airspace in the world. It's pretty cool to be on a ferry and see a plane land basically next to you in the middle of the river.
      • defrost 1y ago
• sandworm101 1y ago
  Sounds like a list of edge cases just like any other area. Myths programers believe about cars: Cars in the same lane always travel in the same direction. Each street has a name. Each street has a unique name. Each street has only one name. Cars have four wheels. Cars never move vertically. Roads never move. Roads never cross water without bridges. When two roads cross, the do so at an intersection. Take any field in human experience and one can make such a list. All boats float. Ships are bigger than boats. Boats are slower than airplanes. Boats only travel on water.
  • lostlogin 1y ago
    > Sounds like a list of edge cases just like any other area. That's exactly the point. The famous example (Falsehoods Programmers Believe About Names) has examples I have encountered in medical databases. If a programmer somewhere didn't fall into the trap, patient names in a medical database would have been better managed and may have avoided duplication, lost records, etc. https://news.ycombinator.com/item?id=18567548 https://news.ycombinator.com/item?id=18567548
  • genewitch 1y ago
    > Ships are bigger than boats to the best of my recollection, the only way to tell a ship from a boat is to watch it make a "high" speed turn, ships lean out, boats lean in. But this is probably incorrect, just like all of my education was.
    • Scarblac 1y ago
      The only one I know is that ships can carry boats, not vice versa.
      • bombcar 1y ago
        Ships can carry ships, though. But then the ship becomes a boat?
    • deleted 1y ago
      [deleted]
• dtgriscom 1y ago
  Another discussion of this article, but on a FlightAware forum: https://www.flightaware.com/squawks/view/1/7_days/popular_new/98475/Falsehoods_Programmers_Believe_About_Aviation https://www.flightaware.com/squawks/view/1/7_days/popular_ne...
• ryandrake 1y ago
  I always look at these "Falsehoods Programmers Believe..." lists as a source of tests. Each item should spawn a number of unit or integration tests that will help to uproot any of these assumptions that were incorrectly baked into your software.
  • jpgleeson 1y ago
    Each of these did indeed spawn tests. I used to work there and at the time there were over a thousand ranging from humdrum to David Blaine skydiving. They’re a crowd who really put a focus on good engineering
    • KingMob 1y ago
      Uhh, and how often were you able to run the Blaine skydiving test? :D
• softwaredoug 1y ago
  Someone should do a logic blogpost - “Falsehoods programmers believe about falsehoods”
  • leecoursey 1y ago
    [flagged]
  • ratmeadow 1y ago
    "Falsehoods "falsehoods programmers believe about falsehoods" blog posters believe about "falsehoods programmers believe about "falsehoods programmers believe about logic" blog" falsehoods"
  • Dylan16807 1y ago
    Why? What would go on it? From that dead comment quoting a chat bot that clearly did not understand the question at all, I think maybe we can extract a single bullet point: * “Edge cases” live only at the edges; they never creep into the middle. But that's not much to build a post with.
  • KingMob 1y ago
    Here's a falsehood list about falsehood lists: 1. I'll never need to learn a falsehood list, so I can skip it. 2. A falsehood list is complete at the time of writing. 3. OK, but it will surely get updated with new falsehoods and clarifications. 4. Skimming the falsehood list is all I need to do to learn it. 5. OK, but surely I'll remember to recheck the falsehood list once I actually need to, right? 6. If a falsehood doesn't immediately make sense to me, there must be something wrong with it, despite the author having domain expertise that I don't. Literally had to point out just last night how UTC is not sufficient in all scenarios. I swear it happens every 6 mos on Reddit.
    • Scarblac 1y ago
      7. These lists are meant to be for entertainment only
  • kdeldycke 1y ago
• zzo38computer 1y ago
  I had known about some of these, and I had thought that some others are at least possible. I know that there is a ICAO code on Mars (since I had read about it before). I think there are some airports that have a ICAO code but not IATA code and vice-versa, and some have a "pseudo-ICAO" code with letters and numbers together.
• moron4hire 1y ago
  I did not believe almost any of these things on account of I try not to think about airports whenever I don't have to.
• genocidicbunny 1y ago
  Funny how the common thread through many of these 'Falsehoods...' posts is that many programmers think that systems designed by humans, for humans, and kept running by humans will rigidly adhere to a set of rules and don't have edge cases.
  • Spivak 1y ago
    I think it's more, "you might think as a programmer writing software that models the world of aviation that you could assume the following things— but alas." Software unfortunately follows rigid rules so the challenge is finding a set of rigid rules that can encompass reality. It would be pretty natural if you were writing a database schema that a flight would have a departing airport and an arriving airport— but alas.
    • genocidicbunny 1y ago
      Well what I'm speaking to more is that most systems that you model, most of the model is already assumptions. So natural or not, that database schema is already invoking assumptions which may or may not be false. Especially when dealing with any system where humans are directly involved in it. For many things, there's no exhaustive list of rules that will cover all the cases. As they say, if you make something idiot-proof, they'll invent a better idiot.
      • bruce511 1y ago
        And this is why I much prefer Suurogate values for primary keys over natural values. And why I've gravitated to using UUID values for surrogates, not integer identities. A theme running through the article is "this value is unique " and "this value does not change". And of course those are both wrong. So when designing databases now I assume "everything changes, nothing is unique " (even when the domain "expert" professes it is.) This approach solves so many problems and saves something time later on when it turns out that that "absolutely, positively, unique for ever" natural key, isn't.
        • 1y ago
• 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 ago
    Aircraft of Theseus
    • sixdimensional 1y ago
      Exactly!
      • Dylan16807 1y ago
        The 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 ago
          The 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.
• lyu07282 1y ago
  Its like receiving some API documentation that confidently declares some field as an ENUM and then a few hundred million rows later you discover that that was more like a suggestion and its actually more like a free text field.. sigh
• usui 1y ago
  Honestly I am surprised by some of the points. But after reading all of it, now I am wondering as an outsider, what the hell is a "flight" if there's basically no good abstraction for this mess? What does it mean when a new flight is created, or what does the existence of any single flight mean?
  • ranger207 1y ago
    It means what it needs to mean so everyone involved will know what it means in the moment
  • gostsamo 1y ago
    Flight is a concept which is at least a body moving without support to an underlying surface. Everything else are human plugins added to help us exploit the concept in various circumstances. Any additional constraints on the concept are valid only in the circumstances they were invented for. Enumeration of the circumstances should take into account the participants of the communication context where the word "flight" is used.
• bnycum 1y ago
  I develop software for flight data analysis at a company that makes flight data recorders. Our focus is mainly helicopters, but some fixed wing. Dealing with aircraft that may takeoff or land at a base, hospital, roof, parking lot, football field, airport, golf course, etc I feel like most of my days are spent on all sorts of falsehoods about aviation.
• ratmeadow 1y ago
  Bit of a rant: what annoys me about these lists is how they just give off a huge "you are dumb for making any assumptions, how could you not think of <extremely obscure edge case>" vibe. I'd be interested to see what the effects are of these assumptions failing, because often they are pretty reasonable assumptions for a reasonable subset of the universe. Software is imperfect and you can't cover every possibility. Like ok technically 10 flights with the same number could leave the same gate at the same time, but if 99.99% of the time they don't and you assume that, what is the real impact to people? Reminds me of a list that came up ages ago that presented an assumption of "X code always runs" with the counterpoint that you could unplug the computer. Ok sure, but then why write software at all? Clearly no point assuming any code will ever run since you can just terminate the program at any random time.
  • saurik 1y ago
    I don't agree that this list has the attitude you describe--if anything, they just seem proud that they have many fewer of these corner case bugs than anyone else--so it is difficult to work with your example of the flight number. These are, in fact, misconceptions made by programmers, often without having the in-depth knowledge of this specific area that comes from being an actual expert (the kind that often people don't allocate for in their budgets), and this list isn't an over-the-top portrayal of such: it feels weird to become offended? That said, I do appreciate some of these lists--which maybe has put you on edge to the paradigm--do have an edge to them... but, in all honesty, I think they should? The bugs and edge cases that these lists tend to expose aren't random glitches that equally affect every user: they usually segment users into the ones whose lives "follow the happy path" (which often just means "are intuitive and familiar to the culture near the developer") and the users who get disproportionately (or even continually!) screwed every time they dare interact with a computer. And like, it is actually a problem that the other side of this is almost always a developer who doesn't really give a shit and considers that user's (or even an entire region/country's) existence to somehow be a negligible statistic not worth their time or energy, and I really do think that they deserve to take some flak for that (the same way I try to not get offended if someone points out how my being a cis-het white male blinds me to stuff: I think I deserve to get held to task harder by frustrated minorities rather than force them to be nice all the time in a world that penalizes them).
• petesergeant 1y ago
  https://www.airnavradar.com/data/airlines/tmw https://www.airnavradar.com/data/airlines/tmw is a good example of some of these (depending on what time you check that link -- if it's night-time in the Maldives it's going to show you nothing)
• ttfkam 1y ago
  Day by day it feels less and less like regular data modeling and more like a debate with Jordan Peterson where you argue for ten hours what a "name" is. Eventually you end up having to make choices and deal with the consequences. Otherwise Jordan Peterson would have you chasing your tail for days about what a "choice" is, and nothing would ever get done. tl;dr: just make your best guess and always include an extra "notes" column where things can get leaky.
  • sgarland 1y ago
    Not days necessarily, but I think quite a bit of time should be spent data modeling, yes. Before you’ve ever touched the keyboard, it’s very helpful to attempt to model the problem on paper or a whiteboard. You quickly find problems with your initial guess that way. Notes / data / extra et. al columns are the worst, as a DBRE. People inevitably shove various shit into them over time instead of making an effort to properly fix past mistakes, and at some point, they practically contain their own table.
• Dusksky 1y ago
  [dead]
• aryehof 1y ago
  Perhaps useful to produce a list of true constraints in contrast to false ones. Perhaps that would result in too many “except for”, “apart from” and “subject to” statements. Aside: is there a notation for such constraints?
  • genewitch 1y ago
    RFC 2119 and be very exact with your language? don't use "MUST" if there's exceptions, for instance.
• throwaway290 1y ago
  Missing "Aircrafts land", the shortest falsehood.
  • chopin 1y ago
    Which aircraft don't land in one form or another?
    • bombcar 1y ago
      Spacecraft are aircraft. Voyager hasn’t landed.
      • account42 1y ago
        Voyager hasn't landed yet.
    • throwaway290 1y ago
      Touchdown on water, on an air carrier, rapid disassembly in air
      • throwaway290 1y ago
        Infinite flight with in air refueling Get stuck in trees or sufficiently big building Change ID while flying and land as a new aircraft (also makes "aircrafts take off" a falsehood)
        • deleted 1y ago
          [deleted]
    • haiku2077 1y ago
      Seaplanes, loitering munitions ("suicide drones")
• EMM_386 1y ago
  Well, as a senior software engineer and commercial pilot ... I am left confused. Not all the things in the list, because I am aware of those. I might have missed the runway numbers changing based on shifting magnetic field of the earth, but that's a thing too. Runway 22? That's now Runway 21. But why programmers specifically would believe this, as opposed to ... any other profession that is not aviation?
  • andoando 1y ago
    The author is a developer at FlightAware, theyre just showcasing the difficulty of writing software for aviation
  • matusp 1y ago
    There is a genre of articles that list similar non-intuitive facts about various domains (people's names, music, etc). The relation to programmers is that they are often creating software systems where some of these facts come into play, e.g., by using some values as primary keys, foreign keys, etc.
    • account42 1y ago
      Yeah but most of those are about generic things that random programmers will likely encounter and might think they understand but actually don't. That's what makes those lists interesting.
  • genocidicbunny 1y ago
    The article isn't meant to imply that only programmers would believe these. It's just a little niche of 'Falsehoods that Programmers believe about XYZ' sort of articles that became popular because programmers tend to write software that ends up interacting with real world systems that have edge cases many programmers would not consider if they're not dealing with the problem space for a while.
    • tekla 1y ago
      Programmers learning that education is a thing
• th0ma5 1y ago
  Another falsehood is that airplane data companies won't cave to legal or monetary threats. They might!
• unkulunkulu 1y ago
  Haha, nice! My head as a programmer explodes while reading this list, because I feel like these are all reasonable assumptions and I feel how they are painfully discovered late into the implementation. Also, feeling myself stupid very quickly. Very nice summary, bravo!
• 1Sebastian 1y ago
  [dead]
• mschuster91 1y ago
  On the ADS-B receiver side, I'd add "Each ADS-B packet will be clearly heard by the on-ground receiver, there will be no other radio station sending an ADS-B packet when another station is actively transmitting" and "Only actual ADS-B stations use the 1090 MHz frequency, no one will attempt to maliciously jam the entire band".
• hermitcrab 1y ago
  >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. Isn't that blindingly obvious? If so, how did it get to be a patent? And is someone now extracting rent from it?
  • diggan 1y ago
    Does it matter if something is obvious or not for getting a patent granted? From some casual looks of various US patents, it seems to be "First who writes a obtuse patent about thing X gets it granted", doesn't really matter if the thing is "novel" or not, just that no one tried to submit it before.
    • ajb 1y ago
      Legally it's supposed to matter, yes. Non-novel or obvious ideas are according to the law not eligible to be patented. In practice the mechanism to decide both of these is broken.
      • diggan 1y ago
        I see, that's really not visible in practice. Silly example perhaps, but US5443036A comes to mind which just shows how broken the system is: > A method for inducing cats to exercise consists of directing a beam of invisible light produced by a hand-held laser apparatus onto the floor or wall or other opaque surface in the vicinity of the cat, then moving the laser so as to cause the bright pattern of light to move in an irregular way fascinating to cats, and to any other animal with a chase instinct. How on earth is anyone supposed to be able to take the patents system as a whole when there are 100s (if not 1000s) of examples like that, which obviously shouldn't be approved if "novel" or "non-obvious" ideas are required.
        • ajb 1y ago
          That one is kind of amazing - I wonder if it was intended as a self-parody of the patent system? But in general yes I agree.
• seydor 1y ago
  [flagged]
• moralestapia 1y ago
  >If an aircraft diverts to another destination, it won’t divert again. Hehe, I was once told we couldn't land at our destination A, so we got diverted to B; while on our way to B we were told we are actually going to C; and, while on our way to C, A became available again so the plane did a U-turn and we flew back to A, landing with a ~3 hour delay. The cause was snow and wind.
• kqr 1y ago
  I find this list strange. I have only a passing interest in aviation and I would not believe very many of these. What made the corresponding lists for names and time interesting were that it was genuinely surprising to realise that their statements were actually false. I don't get that feeling with these. Like the top level comment about identifiers for airplanes -- why would they have them? That sounds baffling to me. With ownership changes, continuous upgrades, extending airframes, repurposing etc. I would be surprised if there was a stable identity.
  • n4r9 1y ago
    Yeah. This list is more like "model simplifications you should think twice about making".
  • amelius 1y ago
    Yes, this list is insulting to programmers.
• b3orn 1y ago
  Here's one that is only kind of mentioned, there are actually different altitudes. If you use ADS-B data you will only get the barometric altitude which is not calibrated to the ground pressure level. For example if you watch ADS-B data of flights into Denver it appears that every aircraft is crashing down ~5000ft during landing.
  • extraduder_ire 1y ago
    Above ground level, and above sea level are two easily confusable ways of reporting altitude. Reporting a value above sea level on ADSB so that it doesn't change is probably the right thing to do, especially since airfields report their local pressure and have their elevation recorded. Expecting every runway to be above sea level is another falsehood. AMS has runways 3 meters below sea level, and I'm sure there's even lower ones on the east side of Africa.
    • cardiffspaceman 1y ago
      https://en.wikipedia.org/wiki/Furnace_Creek_Airport https://en.wikipedia.org/wiki/Furnace_Creek_Airport -64m
• daedrdev 1y ago
  Dont forget float planes can land to a pretty massive number of docks
  • bombcar 1y ago
    They can legally land in any navigable body of water (some restrictions in some areas for national preserves) but some lakes have defined water runways.
• djoldman 1y ago
  Falsehoods people believe about programmers: * Programmers believe they are handling all possible configurations of the universe when putting something into production. * Programmers don't handle all possible configurations of the universe when putting code into production because they don't know any better. Falsehoods people believe about the universe: * There exists a constant. * SI units are constant at all times or everywhere.
  • amelius 1y ago
    Falsehoods people believe about programs: * When a new corner case appears, it is easy to adjust the program to handle it.
    • dotancohen 1y ago
      Falsehoods people believe about falsehoods about programmers: the stated falsehoods are actually false.
• antonvs 1y ago
  [flagged]
  • tomhow 1y ago
    Please don't hector someone like this when someone has shared an interesting story from on their unique professional experience. We detached this comment from https://news.ycombinator.com/item?id=44207171 https://news.ycombinator.com/item?id=44207171 and marked it off-topic.
• antonvs 1y ago
  [flagged]
• Zealotux 1y ago
  Back when I was designing an app for air navigation, I came up with an alternative color scheme for various types of color blindness only to be told the target users were not allowed to be color blind (it was in France, much stricter than elsewhere it seems).
• alphazard 1y ago
  A lot of these so called "falsehoods" are just design failures on the part of programmers. Someone did it badly first, and it stuck, and a second person came in later and is surprised by the bad design. That's not really interesting, it happens all the time in software. So much so that seasoned engineers have come to expect poor design until proven otherwise. Things like flight numbers not having reasonable semantics, or conceptual pollution of what a flight is to include multiple take offs and landings are bad design, plain and simple. Just model the problem correctly e.g. maybe a Trip is multiple Flights, or Flights have multiple Legs. This isn't aviation specific. These are generic problems that programmers can and should get right. Some of it is intrinsic to the domain, like flights not all having gates, or not landing at airports. That was a new tidbit for me.
  • NooneAtAll3 1y ago
    I don't understand your argument it doesn't matter whose failure it is the point of the article (just as with the one about names) is that there are "reasonable defaults" many people would believe - that don't work in practice and become gotchas whether you have enough knowledge to know that something is unreasonable doesn't mean it doesn't seem reasonable for many others
    • andrewingram 1y ago
      And as programmers, we inevitably spend most of our time dealing with these weird edge cases, because the stuff that makes sense is generally incorporated into our initial modelling and becomes a solved problem.
    • alphazard 1y ago
      > it doesn't matter whose failure it is. It does. The distinction between a misunderstanding of aviation, or a misunderstanding of which of many possible models is in place. I'm interested in misunderstandings of aviation. How did aviators think about it before software ever entered the picture? Which of their concepts are coherent, and why do they use them? What reasoning power do those concepts get them? It's interesting when programmers misunderstand that. It's less interesting when programmers setup a poor system for keeping track of things. It could be busses or trains or parts in a factory. It's not aviation specific, and it's run-of-the-mill bad design when it's done badly. Apparently the first software engineers to model aviation were really bad at it.
• jmward01 1y ago
  Adding to the list: Runway numbers never change [1] [1] https://www.ncei.noaa.gov/news/airport-runway-names-shift-magnetic-field https://www.ncei.noaa.gov/news/airport-runway-names-shift-ma...
• oceansky 1y ago
  Can someone clarify this one: "Flights have schedules". Don't they all have schedules?
  • handfuloflight 1y ago
    Schedules have flights.
  • benburwell 1y ago
    Some examples of flights without schedules: - A private pilot who departs their local airport without filing a flight plan and flies around for a while. - A charter jet that departs whenever the passengers show up. - A medevac helicopter departs a hospital to return to its base. While en route, it is rerouted by dispatch to pick up a patient at a different hospital.
• dehrmann 1y ago
  > Flights that depart from a gate only leave their gate once I went on a vacation to New Zealand just before new visa requirements took effect, so while I entered legally, at some point, I couldn't reenter. As I was going through passport control to exit, I asked what would happen if the plane had a mechanical issue and I had to spend the ~night, but couldn't reenter. The border agent said they can undo an exit.
• ivan_gammel 1y ago
  My favorite falsehood was from ca. 17-18 years ago: that altitude is always positive. There are airports in the mountains where approaching altitude can be below the runway and thus reported as negative.
• BrandoElFollito 1y ago
  I love it how some comment threads jumped into solving these false beliefs, with code, standards and everything. Software development is really cool.
• FearNotDaniel 1y ago
  > Everything that has an IATA code is an airport I used to travel fairly often between Salzburg and London Heathrow, which has very few direct flights outside of weekends in the ski season. One option was to book a through ticket on the Lufthansa bus Salzburg-Munich then fly, which meant of course that the bus journey had to have a flight number. I particularly loved that there was a pick up at the halfway point of Rosenheim in Bavaria, which means a lonely bus stop in a car park just off the motorway also got assigned an airport code.
  • FearNotDaniel 1y ago
    I’m not sure what kind of spam merchants operate the website “kiss & fly”, but none of the following claims [0] are true: “IATA code – ZPR. Rosenheim Bus Station operates domestic and international flights. Friendly staff will help passengers with customs and passport control, checked and carry-on baggage. Lounges with comfortable seats, bars, restaurants, duty-free stores, free Wi-Fi will not let you get bored while waiting for your flight.” [0] https://avia.kissandfly.at/en/airport/ZPR https://avia.kissandfly.at/en/airport/ZPR
  • bergie 1y ago
    Lufthansa at least used to operate a "flight" from Frankfurt to Cologne main railway station. This included flight attendants in the ICE train cars, and a luggage conveyor at the railway station
• nly 1y ago
  A lot of these identification issues could be solved with a time series attribute system. For example, a tail number (attribute) could be associated with a plane between X and Y timestamp In financial trading it's also the case that a lot of identifiers change.
• univacky 1y ago
  An aircraft on a flight may not maintain the same identifier/callsign for the entirety of that one flight. Famously, President Richard Nixon departed Washington DC on Air Force One bound for California. In flight over Missouri, his resignation took effect and Gerald Ford was sworn in as President. When that happened, the callsign of the flight changed to SAM 2700. https://en.wikipedia.org/wiki/Air_Force_One#SAM_27000 https://en.wikipedia.org/wiki/Air_Force_One#SAM_27000
• account42 1y ago
  Falsehoods web developers think about URLs: - You can just add arbitrary query arguments to URLs of other websites