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Wanderer · 07-30-2011, 04:54 AM

Water speed (surface speed in mph) - no contragrav...
6 * (LWt * 2000)^(1/9) * (Acceleration)^(1/3) * (Modifier)^(1/3)

LWt is the ships rated mass, Acceleration is the space acceleration in Gs (though some notes state that rockets and rams give only 1/2 their rated thrust in water and should cost a bit more to retain full thrust in space and air), ^(1/9) is ninth root and ^(1/3) third or cube root. Modifier is the hydrodynamic lines modifier, something from 1 to 20 (avg lines are at 10). Same works for underwater performance just as well, except the modifiers are different (avg nautical at 3). To make it into 4th ed stat line i suppose you need to further divide the result (in mph) by two.

Acceleration rate is same as air acceleration.

Crush depth (yards) is different... but i suppose... dDR being the lowest armor rating on the ship.
10 * (dDR + 1) * Frame * Shape / SM

Frame probably should default to 1 and Shape to 3 (maximums being 4 & 24 respectively)
(30 * (dDR + 1)) / SM

No guarantees for the math nor for any of them notes.

07-30-2011, 04:54 AM	#4
Wanderer Join Date: Oct 2004	Re: Water Move for Spaceships Water speed (surface speed in mph) - no contragrav... 6 * (LWt * 2000)^(1/9) * (Acceleration)^(1/3) * (Modifier)^(1/3) LWt is the ships rated mass, Acceleration is the space acceleration in Gs (though some notes state that rockets and rams give only 1/2 their rated thrust in water and should cost a bit more to retain full thrust in space and air), ^(1/9) is ninth root and ^(1/3) third or cube root. Modifier is the hydrodynamic lines modifier, something from 1 to 20 (avg lines are at 10). Same works for underwater performance just as well, except the modifiers are different (avg nautical at 3). To make it into 4th ed stat line i suppose you need to further divide the result (in mph) by two. Acceleration rate is same as air acceleration. Crush depth (yards) is different... but i suppose... dDR being the lowest armor rating on the ship. 10 * (dDR + 1) * Frame * Shape / SM Frame probably should default to 1 and Shape to 3 (maximums being 4 & 24 respectively) (30 * (dDR + 1)) / SM No guarantees for the math nor for any of them notes.