aerospace

Frank Whittle patented the jet engine in 1930. Hans von Ohain flew one in 1939. Neither knew the other existed. Their parallel invention and eventual friendship is the story of modern aviation.

How the liquid-fuel rocket was invented — from Tsiolkovsky's 1903 equation to Goddard's 1926 launch, the V-2, Apollo, and SpaceX's reusable boosters.

A single GE90-115B turbofan is rated at 115,300 pounds-force of thrust. The physics behind it is a short chain of ideas: squeeze air, burn fuel in it, and let the hot gas do work.