Pratt & Whitney's JT9D engine opened a new era in commercial aviation: the high-bypass-ratio engine to power wide-bodied aircraft.

Since entering service on the Boeing 747 aircraft in 1970, the JT9D engine has proven itself to be the workhorse for early 747, 767, A300, A310 and DC-10 aircraft models with more than 3,200 cumulative engines delivered.

The JT9D engine family consists of three distinct series. The JT9D-7 engine covers the 46,300- to 50,000-pound-thrust range, and the JT9D-7Q series has a 53,000 pound thrust rating. Later models, the -7R4 series, cover the 48,000- to 56,000-pound-thrust range. For JT9D-7R4 twinjet installations, the engines are approved for 180-minute ETOPS (Extended-range Twin-engine Operations).

Pratt & Whitney continues to invest in and support the JT9D engines. Reduced Cost of Ownership Kits for the JT9D engine are available to improve durability, increase thrust and reduce noise. With Pratt & Whitney's commitment to the JT9D program, these engines will continue to serve commercial aviation.

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