Obio's thread about the P-47's drop tanks got me thinking again. There are several modern aircraft with drop tanks. Everybody factors in the fuel weight added to the aircraft but no one has actually accounted for the drop tank weight. Does anyone know for example how much an empty US 330 gallon tank for the F-16 or F/A-18 Weigh? the other big one that sticks out are the zeppelin (I think that is what they are called) tanks and the smaller tanks for the Tornado. Empty weights would be appreciated.