出典:Wikipedia
出典:『Wikipedia』 (2011/07/28 17:49 UTC 版)
The Pratt & Whitney Rocketdyne RS-68 (Rocket System 68) is a liquid-fuel rocket engine that burns liquid hydrogen (LH2) with liquid oxygen (LOX). It is the largest hydrogen-fueled engine in the world. Development of the engine started in the 1990s with the goal of producing a simpler, less-costly, heavy-lift engine for the Delta IV launch system. The engine has three versions: the original RS-68, the improved RS-68A, and the RS-68B for NASA.