Pratt & Whitney has received a contract to produce the 12th and 13th lots of F135 engines for the F-35 Lightning II joint strike fighter aircraft.

The F135 propulsion systems will power all three variants of the Lockheed Martin-built F-35.

Pratt & Whitney noted that the award is the largest-ever F135 production contract received by the company.

Under the contract, the company will provide more than 332 engines for the US Armed Forces and international customers.

The firm will also provide engineering support, programme management, production support and tooling.

The contract covers Lot 12 and Lot 13 and also includes priced options for Lot 14 production. The total value of the contract is estimated to be around $5.7bn.

Pratt & Whitney Military Engines president Matthew Bromberg said: “This is a significant milestone for the programme and underscores the hard work of our joint government and industry team.

“We’re proud to be delivering fifth-generation propulsion capability at a great value for the warfighter.

“With more than 500 F135 engines delivered to date, we’re at an exciting inflection point for the program. We are laser-focused on standing up an effective global sustainment network that will support the F135 throughout its lifecycle.”

The F135 engine delivers more than 40,000lb of thrust and enhanced performance and reliability.

The US Department of Defence announced on 1 October that Pratt & Whitney was awarded a $2.19bn modification by the Naval Air Systems Command to a previously awarded contract for the F135 propulsion systems.

Pursuant to the modification, the company is required to deliver 112 F135 propulsion systems for the airforce, 46 for the marine corps, and 25 for the navy.

The F135 is based on the F119 engine, which powers the US Air Force’s F-22 Raptor stealth tactical fighter aircraft.