[sokoloff]

I would think that most of that energy is used to transport the 747 1/3 of the way around the earth, overcoming induced and parasitic drag for 8+ hours.

From a straight lifting standpoint, lifting 910K pounds to 37K feet takes about 45 billion joules, which is the energy content in about 320 gallons (~2200 pounds) of jet fuel (if consumed perfectly efficiently).

A 747 burns about 1 gallon of fuel per second, meaning the straight lifting fuel consumed represents about 5 minutes or 1% of the fuel consumption on the flight.