The Hidden Engineering of Runways

(practical.engineering)

74 points | by crescit_eundo 6 days ago ago

8 comments

  • jld 44 minutes ago

    I saw a talk a long time ago about the structural aspects of runway design. The most interested fact I remember was that the stresses on the runway generated by departures was higher than those of arrivals, as departures repeatedly stress the same part of the runway, while jets land on a much more distributed area of the runway.

    Plus jets weigh a lot less at arrival than at departure.

  • r-johnv 4 minutes ago

    I absolutely love that Grady includes full transcripts of his videos.

    It's much faster to read the article than watch the video, even though that hurts him by 1 view.

    I just watched parts of the video after reading because I wanted to see his explanations.

    One of the few really good creators out there.

  • noitpmeder an hour ago

    Video is great, came up in my youtube recommendation cycle last week.

    Honestly one of the better things youtube has pitched to me, the quality/relevance of the rest of its recommendations have been nose diving over the last year (or so it feels).

    • ashf023 15 minutes ago

      100%. I've always used youtube on desktop (connected to the TV usually), and it seems to me they're just making all versions of youtube into a mobile app optimized for shorts type content. Recommendations are hugely influenced by what you watched very recently. What used to be related videos in the side panel of the player is now just the home page again, but vertical. Even just generating a recommendation from "Whatever (part 2)" to "Whatever (part 3)" is hit or miss now. Some of the recommendations are actually quite good, but at least for the way I like to watch, it's only getting worse over time. The category labels on the home page are also pretty telling - horrible labels (e.g. I watch some cooking/recipe videos and the label will be "Baking sheets" or something like that), plus it emphasizes the recency bias when it shows 5 categories that are basically just the same content with different labels and forgets what I've always liked watching.

    • graypegg an hour ago

      100% anecdata, but I think YouTube nudges your ad profile towards some averaged out cosign product of everyone’s ad profile at regular intervals.

      I’ll discover something new, then get pushed a ton of things related to it, which is really good! After a very long break of ~4 years, I started playing oldschool RuneScape again, and that interest weaved its way into my recommended feed perfectly for a month. Felt like I was picking up where I left off, new folks making OSRS video essays, folks I remembered from a long time ago that I had unsubscribed from, exactly what I want out of an algorithmic feed when I’m freshly into something.

      Then BAM, gaming content. Some sort of threshold gets hit and now I’m being pushed hyper popular gaming content regardless of RuneScape-y-ness. There’s still a nudge towards it, but I got placed in some “gaming” cohort and it totally crowds out my recommended feed. I don’t really do much gaming outside of this stupid old MMO!

      All that’s to say: it might have been a year since you last had one of these inflection points where YouTube will let your ad profile exist as an outlier for a bit.

    • shagie an hour ago

      One of the issues of YouTube is there is "discovery" vs "what I want to watch". https://www.youtube.com is ok for discovery and pulls a lot of the "this is what I've subscribed to" in there too. Doing a subscribe to channels that give you consistent media that you want to watch and then going to https://www.youtube.com/feed/subscriptions as the "this is where I want to be when on YouTube" gives a completely different experience.

      (I'm also quite free with the "don't recommend this channel to me" option if something disappoints me)

    • spike021 6 minutes ago

      The way Youtube (and I've started to notice in other platforms) does recommendations, for every 5+ that are nonsense, I'll get one I like. Youtube will then start showing me more of that video's channel content and similar channels for a week or so, and then it'll just stop showing any of it to me quite randomly. Sometimes it's when I click on that random recommendation out of 5 from a different topic.

      then the cycle starts again. sometimes youtube brings the content back and sometimes i really need to hunt for it.

      it's almost like they base interests into like a top 3 or so list and if the third favorite one cycles out a lot (however they deem it is being cycled out) they'll stop recommending or otherwise showing it to me.

  • danpalmer 11 minutes ago

    We had group coding projects at university, and the first one was always "sponsored" by the local airport. I think the ATC manager was friends with a lecturer. Every year the students built to the same spec in groups, being able to compare and contrast. It was great fun.

    The year before me was all about runway markings: take a bunch of industry specified XML describing the runway and produce accurate diagrams in a GUI browser.

    My year was runway "redeclaration", if a vehicle has broken down on the runway, you can still use the runway as a shorter strip, accounting for the onion layers of different zones radiating out from the tarmac itself, accounting for the height of the obstacle and angles of approach, accounting for all the necessary safety margins.

    It was my first real exposure to working in a team and to solving a real world problem with a good spec. Of course it was an absolute shitshow, but I look back on it fondly.