Originally Posted by
BEagle
Actually, my value for water density was for 15 deg C!
...which was why you got the wrong answer
The correct method is to convert SG@60F to density at 15C in vac, you can either use a formula similar to BEagles above (but using dens water at 60F and then using volume factors to convert to 15C) or simply accept it from me that in the gasoline range the difference is 2 Kg/m3. Thus for an SG@60F of .7523 the density@15C would be 0.7521 in vacuum. To get the density in air you should then subtract a further 0.0011 from that, giving a density @15C in air of 0.7510. Thus 1000 litres would weigh 751.0 Kg.
Of course, for aircraft sized tanks the above is irrelevant as the differences are insignificant
