F-35 Block Four testing includes two types of F135 engine
Pratt & Whitney to make STOVL and conventional engines.
Raytheon Technologies company Pratt & Whitney was awarded a contract on 5 February to produce F135 engines for three F-35 Lightning II Block Four developmental testing aircraft.
One of these engines will be a conventional take-off and landing variant for the F-35A and F-35C; the other two will be two-cycle engines (each with a forward lift fan) for the F-35B STOVL aircraft.
Work on the $49.19 million contract modification from US Naval Air Systems Command will be completed by January 2023.
The developmental test programme for the F-35 Lightning II Block Four (the most advanced standard) will support the USAF, USN, USMC and non-DoD participants.
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