Slower than the speed of sound

So I asked our resident expert, the internet. After an exhausting 12 second search, it seems the groundspeed was NOT know before satellites (GPS). Further, one cool explanation of pre-GPS was:

Simply put, the pilot notes the time they passed over a landmark on their route. Some time later they would do the same again. Knowing the distance between the two points, and the time taken, a pilot can calculate ground speed…speed = distance/time…either mentally, if the numbers are relatively easy, or by using a computer like this…

George K · "Now look here, you Baltic gas passer... " - Mik, 6/14/08

"Computer," LOL.

Copper

@89th said in Slower than the speed of sound:

before satellites

Google has let you down.

There was a system known as LORAN. I used it when I first started flying. It was decommissioned in 2010. There were ground-based broadcast stations that were used kind of like GPS. This was widely used in general aviation.

There was also inertial navigation, but that was mostly used by astronauts.

And sadly, I doubt if the younger generation can deal with an E6B.

Jolly

Couldn't WW2 navigators do celestial observations? Could they plot ground speed by that?

Copper

Yes, 2 positions and a clock should do it, your accuracy may vary.

LuFins Dad

Virgin Atlantic flight from Dulles to London just did the same thing. Apparently the Gulf Stream is NUTS right now.

https://www.flightaware.com/live/flight/VIR22/history/20240218/0410Z/KIAD/EGLL/tracklog

https://www.washingtonpost.com/weather/2024/02/18/record-jet-stream-winds-dc-flights/

The New Coffee Room

Slower than the speed of sound