Most modern commercial and private aircraAll Postsft which you see in the skies today are powered by jet engines.
These unique engines require special jet fuel.
How much does jet fuel weigh?
Jet A and Jet A-1 jet fuel weigh 6.8 pounds (3.08 kg) per US gallon.
A jet engine is an extremely powerful machine that can turn energy-rich jet fuel into a powerful force which is known as thrust. This is what moves the plane forward, causing air to move along the aerodynamic body and wings to create lift.
Gas turbine is another more technically correct name for a jet engine.
Jet fuel, also known as aviation turbine fuel (ATF) is a special type of fuel which is designed specifically for aircraft use.
There are a number of different types of jet fuels which are produced to international specification. They are Jet A and Jet A-1. There is also a Jet B which is designed to give better performance in cold weather.
Jet A fuel is not available outside of the USA except for a couple of airports in Canada, whereas Jet A-1 is a standard type of fuel available internationally.
For safety and performance, it is essential that a pilot can calculate the weight of an aircraft at any given time. Therefore, to make easier to calculate flight loads, jet fuel is sold by weight rather than volume.
~ Fun Fact ~
A Boeing 747 can suck in enough air through its jet engine to fill a Goodyear blimp in 7 seconds.
Resources
https://www.explainthatstuff.com/jetengine.html
http://science.answers.com/Q/How_much_does_a_gallon_of_jet_fuel_weigh
https://en.wikipedia.org/wiki/Jet_fuel