Fuel density for a given fuel is temperature related.

Hot fuel is less dense.

This was always a problem with long range flying out of hot places. Flying out of Cairo or Tel Aviv in the summer at hot temps - always - would limit the number of gallons of fuel you could put in the tanks. Fueling from underground storage helped a lot to get more fuel on the plane since the fuel was cooler.

Airlines use only Jet-A or A-1 which on a standard day (15 degrees C ) yields around 6.7 pounds/gal. The difference in Jet-A or A-1 is the amount of antifreeze in the mix. Never saw other fuels like Jet-B at the airports we flew into.

Lou