Three Pratt & Whitney Rocketdyne RS-68A Engines Power Delta IV Heavy Upgrade Vehicle on Inaugural Flight

Video Credit: SpaceVidsNet, via YouTube

The sky rumbled and the ground shook as the three most powerful hydrogen-fueled liquid rocket engines ever built successfully boosted a U.S. government satellite into orbit on June 29. Developed by Pratt & Whitney Rocketdyne, the RS-68A engines thundered into the sky on their inaugural launch, boosting a United Launch Alliance Delta IV Heavy rocket from the pad at Cape Canaveral Air Force Station, Fla. Once above Earth’s atmosphere, the reliable Pratt & Whitney Rocketdyne RL10B-2 engine provided upper-stage propulsion.

The RS-68A is a liquid-hydrogen/liquid-oxygen booster engine designed to provide increased thrust and improved fuel efficiency for the Delta IV family of launch vehicles. It evolved from the RS-68 engine, which was developed and certified for commercial use with private company funds. Each RS-68A provides 702,000 pounds of lift-off thrust, or 39,000 more pounds of thrust than the RS-68 engine, with increased combustion efficiency as well. During hot-fire tests, the RS-68A engine demonstrated the ability to operate for 4,800 seconds of cumulative run time – more than 10 times what’s needed to boost the Delta IV Heavy rocket into space.

Click here to read Pratt & Whitney's press release. 

Coverage:

• Delta IV launch: Secret, but very loud (Florida Today)
• World's most powerful rocket launches secret US satellite (Christian Science Monitor)
• Delta IV rocket launch from Cape Canaveral video (ABC Action News)
• Delta IV rocket launches into space (WMKG Orlando)