The US Air Force today issued an open-ended request for proposals (RFP) to industry for a new combat search and rescue (CSAR-X) helicopter fleet.

Although the USAF invites the three competitors – Boeing, Lockheed Martin and Sikorsky – to submit proposals, no date has been set for contract award. The programme could be reviewed by the new administration that takes office in January.

The final terms for the third bidding process for CSAR-X include schedule and funding updates. The first 10 new helicopters must be delivered between the third quarter of Fiscal 2013 and the second quarter of FY2015.

The USAF has budgeted $2.9 billion for the first five years of the development phase.

The long-awaited contract for 141 helicopters is worth an estimated $15 billion.

In November 2006, the USAF originally awarded the contract to the Boeing HH-47. However, Lockheed Martin and Sikorsky successfully protested that decision, and also blocked the USAF’s second attempt to award a contract.

For this third attempt, the USAF had planned to release the amended RFP in October. But the process was stopped again after the office of Secretary of Defense Bob Gates determined that the tender required further clarifications.

Boeing is competing against the Lockheed Martin/AgustaWestland US101 and the Sikorsky HH-92.