[LoBlo]

Here's a question for those naval history buffs out there. Where do the terms ahead one-third, ahead two-third, ahead standard, ahead full, and ahead flank originate from? Meaning at which era and navy did they become commonly used terms? WWII? WWII? Pre-WWI?

A related question is: In a modern navy, do these terms still mean 5knots, 10knots, 15knots, 20knots, and 100% engine power respectively? (I remember playing 688 attack sub a while back and in that game 1/3rd = 8 knots, 2/3 = 16 knots, standard = 25 knots, full = 32knot, flank = 37knots)