United Technologies Corp’s Pratt & Whitney unit has been awarded a contract for the procurement of 36 low-rate initial production 4 (LRIP 4) F-135 propulsion systems for the US Air Force (USAF).

The $910.1m firm-fixed-incentive-fee / cost-plus-incentive-fee contract is a modification to a previously awarded undefinitised contract action under the F-35 fighter jet programme.

Under the contract, the company will also provide ten conventional take-off and landing (CTOL) propulsion systems, two spare engines, initial spare modules and spare parts for the USAF.

The company will also provide associated engineering assistance to production, special tooling, special test equipment, production non-recurring effort, sustainment activities, autonomic logistics planning and management.

Work will be performed in East Hartford, Connecticut, Indiana, US, and is expected to be complete in January 2013.

The contract also combines purchases for the US Navy and the UK.