Alan Epstein is quick to tell you he's a "jet engine guy" - just in case you havent guessed as much from the turbine engine parts strewn around his office or the museum on his labs ground floor, which includes a rare example of a 1944 German engine that helped kick off the jet age. For the director of MITs Gas Turbine Laboratory, who stands a slightly stooped five foot six, the fascination has to do with raw power. The engines on a Boeing 747 shove air through at Mach 1 with 120,000 pounds of force, says Epstein. The engines on three 747s put out as much power as a nuclear power plant.

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