3 ms·

The fact that this person put a snarky (???) next to the concept of measuring airspeed in knots makes me wonder just how familiar they are with aerospace in gen

The fact that this person put a snarky (???) next to the concept of measuring airspeed in knots makes me wonder just how familiar they are with aerospace in general. A knot is a standard measurement in part because one nautical mile is equal to one minute of latitude. Which is useful until the day we decide to start measuring lat/long in radians. I know it's fashionable in some circles to dump on everything non-metric, but these things are they way they are because of reasons, and airspeed is generally measured in either knots or Mach.

fsckboy 1y ago
>airspeed is generally measured in either knots or Mach boatspeed is also measure in knots... but only very rarely in Mach (and not even primarily because the speed of sound in water is substantially higher than in air)
- psunavy03 1y ago
  Historically, I'm fairly certain airspeed was measured in knots because of boatspeed. In software terms, the problem of navigating over the Earth's surface was forked from boats to planes, and why re-invent the wheel? It also tends to be more of a standard in professional aviation, whereas some small civilian bugsmashers in the US use MPH, presumably because it's easier for the doctors and lawyers of the world to understand after driving their cars, and if you're VFR, who really cares?
  - p_l 1y ago
    US customary is prevalent because USA after WW2 was the China of aviation - market got flooded by aircraft that had us customary units. Nautical miles and knots were present in long range navigation, especially oceanic
justsid 1y ago
As someone who works in flight simulation I was also taken back hard by this. We are internally metric all the way, but even so the knot is not a weird unit in this space at all. I also never heard about those coordinate conventions.
vazgriz 1y ago
Hi author here, I have worked in the aerospace industry on flight control systems. I'm very familiar with knots as a unit. I'm just annoyed that so many educational resources and even flight code still use customary units for everything. I believe that metric should be used for all internal calculations and knots should only exist at the UI layer for the pilot. When I play flight games though, I only have intuition for speed in terms of knots. Like 150 kts is takeoff speed and 400 kts is the corner speed. I just think that the pilot letting out a spool of knotted rope from their plane is a very silly practice to defend :)
- p_l 1y ago
  I learnt to fly in metric, every time I see feet and feet-per-minute in sims I'm confused as hell, and you can't ask virtual ATC to switch to metric. At least nautical miles and knots have some use on this planet specifically...

fsckboy 1y ago

>airspeed is generally measured in either knots or Mach boatspeed is also measure in knots... but only very rarely in Mach (and not even primarily because the speed of sound in water is substantially higher than in air)

psunavy03 1y ago
Historically, I'm fairly certain airspeed was measured in knots because of boatspeed. In software terms, the problem of navigating over the Earth's surface was forked from boats to planes, and why re-invent the wheel? It also tends to be more of a standard in professional aviation, whereas some small civilian bugsmashers in the US use MPH, presumably because it's easier for the doctors and lawyers of the world to understand after driving their cars, and if you're VFR, who really cares?
- p_l 1y ago
  US customary is prevalent because USA after WW2 was the China of aviation - market got flooded by aircraft that had us customary units. Nautical miles and knots were present in long range navigation, especially oceanic

justsid 1y ago

As someone who works in flight simulation I was also taken back hard by this. We are internally metric all the way, but even so the knot is not a weird unit in this space at all. I also never heard about those coordinate conventions.

vazgriz 1y ago

Hi author here, I have worked in the aerospace industry on flight control systems. I'm very familiar with knots as a unit. I'm just annoyed that so many educational resources and even flight code still use customary units for everything. I believe that metric should be used for all internal calculations and knots should only exist at the UI layer for the pilot. When I play flight games though, I only have intuition for speed in terms of knots. Like 150 kts is takeoff speed and 400 kts is the corner speed. I just think that the pilot letting out a spool of knotted rope from their plane is a very silly practice to defend :)

p_l 1y ago
I learnt to fly in metric, every time I see feet and feet-per-minute in sims I'm confused as hell, and you can't ask virtual ATC to switch to metric. At least nautical miles and knots have some use on this planet specifically...