Manual TDC speed figuring

[Rockin Robbins]

Originally Posted by DrBeast

I use the simple 3min 10sec rule: jot down the position of the ship on the map, start the watch, and put down the next mark after exactly 3 minutes and 10 seconds. I then measure the distance traveled in Km, multiply by 10 and hey! presto, I have the target's speed in knots. Being a European, I don't bother with feet, hands, brows, or any of that jargon: it's metric system for me. :p

*DrBeast sits back and waits for Rockin Robbins to come charging in

I always pause and zoom in completely when I'm jotting down the marks and measuring, that could help a bit.

Charrrrrrrrrrge! In human measurement terms, use the 3 minute rule. Distance traveled in nautical miles (the knot is nautical miles per hour. That's a CLUE!!!:rotfl times 20 is speed in knots.

If they have the sense to use knots, you'd think they would have the sense to use sensible units all the time instead of mixing them all up. And hey, these are American boats. We'll have none of that kilohertz stuff here, it's kilocycles!!!! Ya see, that term actually MEANS something. All those Europeans HATE words that actually mean something... Maybe that's why they speak all those foreign languages? OUCH! Onkel Neal, he hit me!