Depends on the plane and the load factor. Assuming a conservative 80 mpg per seat a flight from Moscow to London would consume the following to move your tail between locations:

1554 miles / (80 miles/gallon) * 6.8 lbs/gallon = 132 lbs

I was actually a bit surprised how little it is. It gets better in newer aircraft assuming all seats are taken.

[1] https://en.m.wikipedia.org/wiki/Jet_fuel

[2] https://en.wikipedia.org/wiki/Fuel_economy_in_aircraft#Mediu...