No, the indicated weight of fuel in this aircraft is calculated by means of resistance (I happen to be type rated
).
You see, the amount of fuel loaded in egypt will be correct on ground. Once airborne, temp decreases and volume will be slightly less due to the problem with MD80's resistance type fuel qty system. It measures the quantity and assumes a temp from the resistance. The allowed error is 270kgs with full tanks and a density of 0.803. Lower density = my margins shrink! Do you see the point?
So, if I could calculate the specific gravity with only a constant and fuel temp, I could disregard any changes in fuel temp/density at cruise.