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View Full Version : Torpedo speeds, yards per minute


Sniper297
04-09-15, 03:36 PM
Landlubber FAQ: "What's the difference between a statute mile and a nautical mile?"

Crusty old salt: "A nautical mile is a little bit longer and a lot wetter!" :arrgh!:

After doing the calculations I googled nautical mile, international accepted standard is 6076 feet. I used 6080 feet because that's what my US Navy Bluejackets Manual said, and the difference would be insignificant enough that I'm too lazy to bother doing it over. Origin of the nautical mile is one minute of arc at the equator, the disagreement is over what type of map projection was used by who and when.

A KNOT is one nautical mile per hour, you don't say "knots per hour" because it's redundant. Yankee Doodle warships in World War Two used yards to measure range, not meters, so the speeds I used are yards per minute, expressed as YPM. You can divide by 2 or 4 or 60 to come up with your own list for how many yards in 30 seconds, 15 seconds, or one second, whatever floats your boat. Anyway here's the numbers based on torpedoes_US.sim:

Mark 10 1216 YPM (36kt)
Mark 14 low speed 1041 YPM (31kt)
Mark 14 high speed 1554 YPM (46kt)
Mark 16 1554 YPM (46kt)
Mark 18 979 YPM (29kt)
Mark 23 1554 YPM (46kt)
Mark 27 405 YPM (12kt)

SSI01
04-09-15, 05:18 PM
Again, much appreciated!

PS - If you were a female navigator, and you were taking this measurement at the equator, would that make you "Joan of Arc?"

Sniper297
04-09-15, 06:41 PM
Only for a minute. :up: