A multibillion-dollar military contract to build fighter jet engines is on a trajectory to add hundreds of jobs at Pratt & Whitney’s sprawling plant in North Berwick.

About $81 million is coming to Maine, or 4% of a $2 billion contract announced June 5 by the U.S. Department of Defense. An additional $7 million, or nearly 1%, of an $888 million initial award announced last week, already is heading to Maine.

Visitors inspect a jet engine made by Pratt & Whitney at an air show in Farnborough, England, in 2022. Frank Augstein/Associated Press

A branch of Raytheon Technologies Corp., Pratt expects to complete a preliminary design review for an F-135 engine upgrade and move into a detailed design phase in early 2024, company officials announced from the Paris Air Show on Monday.

To meet that timeline, the company is more than doubling the size of its engine upgrade team, from 200 to 500 people, Jill Albertelli, president of Pratt’s military engines division, said in a written statement. The F-135 program about 53,000 jobs across 36 states, according to the company.

The contracted work at the 1 million-square-foot North Berwick plant is expected to be completed in December 2026, according to Defense Department announcements. Pratt was awarded a $115 million contract in December 2022 and additional funding was provided in the fiscal 2023 Defense Appropriations bill.

The F-135 engine powers the F-35 Lightning stealth fighter jet, which is made by defense giant Lockheed-Martin and used by the Air Force, Navy and Marine Corps. One of the world’s most advanced military aircraft and launched in 2001, the plane has come under criticism recently for production delays and cost overruns. In the past year, the Pentagon has considered replacing the engine with a new one.

But in March, the Defense Department chose to upgrade the F-135 engine rather than replace it entirely, possibly by another maker. The decision was factored into President Joe Biden’s 2024 budget proposal.

“An upgrade will give the engine the capabilities it needs to meet and exceed the F-135’s growing requirements for power and thermal management while improving durability and restoring life to the engine,” Jen Latka, Pratt’s vice president for the F-135 program, said in a statement.

The total contract will fund over 418 F-135 engines with options for the U.S. as well as international customers, Latka said. The contract also includes program management, engineering support, production support and tooling.

As of December 2022, Pratt had delivered more than 1,000 F-135 engines. Since the program’s inception, the company says it has worked to drive production efficiencies, optimize its supply base and invest in strategic initiatives to reduce costs wherever possible.

As a result, the company says it has reduced the average cost of an F-135 engine by more than 50%, contributing to an estimated $8.1 billion in cumulative savings over the life of the program.

“This contract award enables us to continue delivering critical fifth-generation propulsion capability to the warfighter at a fair and reasonable cost for the taxpayer,” Latka said.

Based in Waltham, Massachusetts, Raytheon is the world’s largest aerospace and defense company, with 195,000 employees. Pratt & Whitney, based in Hartford, Connecticut, is a global leader in the design, manufacture and service of aircraft and helicopter engines, and auxiliary power units.