The initially wide field of contenders for the U.S. Air Force’s T-X jet trainer replacement program has narrowed as industry awaits the release of a request for proposals (RFP), which the service expects to issue late next year. Early requirements released by the service appear to have ruled out some aspirants.

The USAF seeks 350 new T-X jet trainers to replace the 431 Northrop T-38 Talons operated by the Air Education and Training Command. It plans to attain initial operational capability of the new jets in 2023.

Earlier this year, Northrop Grumman announced it will propose a clean-sheet design for the T-X requirement, departing from its arrangement with BAE Systems to offer the latter company’s Hawk jet trainer, although Northrop Grumman is still teamed with the British company. In March, General Dynamics withdrew from its partnership with Italy’s Alenia Aermacchi to offer the latter’s M-346, quoting business reasons, but Alenia told AIN that it is looking for another U.S. partner. Lockheed Martin and partner Korea Aerospace Industries have proposed the latter’s T-50 trainer.

Boeing and Sweden’s Saab signed a joint development agreement in December 2013 to offer a clean-sheet design. At a media briefing ahead of the Paris Air Show, Jeff Kohler, v-p for international business development with Boeing Military Aircraft, said that Saab brings “some unique skills, and its experience in smaller fighters.”   

The USAF released T-X requirements this March, making the program the first to produce requirements under the service’s “bending the cost curve” initiative to reduce cost, in part by engaging industry earlier in the procurement process. The more than 100 requirements emphasize three key performance characteristics—sustained-G turns, simulator visual acuity/performance and sustainment—that the USAF identifies as “most critical” for the T-X to meet its training mission.

Textron AirLand is another potential contender that could offer its new Scorpion light attack and reconnaissance jet for the T-X program. But the USAF’s stated requirement for sustained G turns in particular would demand a higher-thrust engine and a wing different from the Scorpion's current unswept design.

“We would be looking at a derivative with a different wing and engines to meet the sustained-G requirement,” Dale Tutt, the Scorpion program’s chief engineer, told AIN. However, Tutt said a recent request for information from the USAF omitted the sustained-G requirement, so “there seems to be some reassessment of that.”

During a presentation to U.S. exhibitors at the Paris Air Show, Air Force Secretary Deborah Lee James said the requirements that the service released in March are “final.” Asked to elaborate, she described a tiered approach to the requirements with “objective” and “threshold” levels. “Threshold—think of that as the bare minimum requirement—and think of the objective requirement as something that we would like to have, but we very much want to understand the cost-capability tradeoff,” she said. “Once we understand that more, it might be that we’re willing to pay for the objective level [or] maybe not. We consider these to be final requirements…we don’t want to keep changing our minds,” James added.

Industry has called on the Air Force to “tell us your requirements early—ideally one or two years ahead of the RFP—and involve us in it so we understand what the source selection is and don’t change it,” related Bill LaPlante, assistant secretary for acquisition. “That’s exactly what we’re trying to do with the T-X.”

LaPlante said the service typically makes a contract award within eight to 12 months of releasing an RFP. “I’m going to strive for seven months,” James interjected. “But we need to do it right.”