F-35 Joint Program Office, Pratt & Whitney Conclude Engine Investigation, Agree to Contract for Eighth Lot of F135 Engines

The U.S. Department of Defense awarded Pratt & Whitney a modification to a previously awarded contract for the eighth lot of F135 propulsion systems to power F-35 Lightning II aircraft. Today's announcement for $793 million raises the total contract value to $1.052 billion. Previous awards, valued at $259 million, were given for long lead items and sustainment.

The low rate initial production (LRIP) contract for the eighth lot will deliver 48 total engines. The contract also includes program management, engineering support, and spare modules. Average prices for the conventional takeoff and landing and carrier variant (CTOL/CV) and short takeoff and vertical landing (STOVL) variant engines were reduced roughly 3.5 to 4.5 percent respectively from LRIP 7 to LRIP 8.

"Pratt & Whitney continues to keep their commitment to lower costs for the F135 propulsion system," said Lt. Gen. Chris Bogdan, F-35 Program Executive Officer. "The government has negotiated a price reduction for every lot of engines, and the latest LRIP 7 and 8 contracts have demonstrated Pratt & Whitney's commitment to the plan."

"Pratt & Whitney and our supply base remain focused on delivering the F135 propulsion system on or below the cost targets we committed to for our customer," said Chris Flynn, vice president, Pratt & Whitney F135/F119 Engine Programs. "The entire production enterprise is focused on meeting our cost and schedule commitments."

The LRIP 8 contract was awarded at the conclusion of a joint investigation into the root cause of the June 23 engine mishap on an F-35A at Eglin Air Force Base. The investigation concluded that a "hard rub" between the Rotor 3 and the polyimide stationary seal on Stator 2 led to excessive heating and fracturing of the rotor in the fan section of the engine.

"Pratt & Whitney and the JPO worked around the clock and conducted an extensive investigation, and we are confident that we now have improvements in place that will allow us to resume normal flight operations," said Bogdan. "We flew the in-flight rub in maneuver with aircraft AF-4, and the engine components looked great in follow up inspections. We also conducted flight tests with pre-trenched hardware on AF-2 with similar results."

"We are working closely with the JPO and the Services to expand the flight envelope and to finish the last stages of development," added Flynn. "Pratt & Whitney stands behind the F135 engine and continues to support the operational fleet. We are working closely with the JPO to finalize the fleet upgrade plan to meet key initial operational capability milestones."

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