For a time it seemed another competitor in the US Air Force’s T-X trainer recapitalisation would bite the dust any day, with Raytheon and Northrop Grumman withdrawing their trainer bids in quick succession earlier this year. Raytheon bowed out in late January, ending its partnership with Italian aircraft manufacturer Leonardo, and Northrop announced it would pull out just days later, saying the company decided the benefits of winning the contract outweighed the costs.

But once the dust settled, the T-X competition returned to full force. The current field pits two of America’s largest aircraft manufacturers against each other, while Leonardo returned as a solo competitor. Meanwhile, Stavatti Aerospace entered the Javelin into the competition, though little fanfare has followed the announcement.

As Boeing and Lockheed go head to head on international fighter competitions, the USAF’s trainer recapitalisation remains an attractive prize and a potential lifeline for Boeing, which has seen dwindling fighter sales in recent years. With the USAF’s next-generation bomber and fighter competitions already awarded, the trainer stands as one of the air force’s last major recapitalisations for years to come. The service is calling for five engineering, manufacturing and development (EMD) aircraft and plans to purchase at least 350 T-X jets to replace its 55-year-old T-38C Talon fleet.

Along with its Swedish partner Saab, Boeing is pitching a custom-designed T-X for the USAF. Boeing inked an agreement with Saab three years ago to design the T-X together and unveiled its aircraft this September in St Louis, Missouri. Boeing is planning final assembly and checkout in St Louis, but has not elaborated on workshare with Saab.

While its competitors are betting low with off-the-shelf aircraft, Boeing is pursuing the air force’s incentives that exceed the aircraft’s requirements. In draft request for proposals released last July, the air force offered an adjusted price to contractors who offered a trainer with higher sustained G and manoeuvring, as well as lower turn-around time. Offerers could also receive additional decrements for a ground-based training system and aerial refuelling full integration.

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The result from Boeing is an aircraft with built-in aerial refuelling and shoulder-mounted anhedral wings to provide easy access for maintainers.

“I need a high wing to be able to have easy maintenance, so we really thought through when we said purpose-built,” programme manager Ted Torgerson told reporters during a May tour in St Louis. “The reason we’re not an off-the-shelf airplane trying to be something else, that was the decision we made, we wanted to do what the air force required so we thought about every little thing."

Although Boeing’s T-X is a new design, Torgerson maintains the T-X was never an experimental aircraft. Boeing has a Federal Aviation Administration experimental certification on both of its jets, T-X1 and TX-2, but needs additional hours before deciding whether to fly with reporters, he says. The two aircraft are the same with the exception of some instrumentation differences, he adds.

“These are airplanes that are ready to go support the US Air Force in EMD today,” Torgerson says.

Unlike some aircraft competitions, the air force will not conduct a fly-off for T-X. Instead, companies will write proposals with flight test data from a production relevant aircraft and submit the information by 28 June, according to Torgerson. After the award, the USAF will conduct a series of reviews and the winner will go through a requirements review and flight test.

“We built two because we wanted to prove that we weren’t just a demonstrator, we had an airplane we could build repeatedly.” Torgerson says. “[We] flew two airplanes together because all of those things are important to show you’re mature, that we’re ready to compete against an off-the-shelf jet.”

Lockheed has taken a more Spartan approach with its T-X bid, taking Korean Aerospace Industry’s T-50 aircraft off the shelf. Lockheed pushed its ready-to-fly strategy with a strong media blitz this spring, putting reporters into the trainer’s backseat and flying over Lockheed’s planned T-X final assembly facility in Greenville, South Carolina. Earlier this spring, Lockheed announced plans to move its F-16 production line from Fort Worth, Texas to Greenville. The company plans to leverage pieces from the Falcon to build the trainer.

During a media flight this spring with FlightGlobal, we kicked the tires on the T-50. Although the aircraft traces its roots back to Lockheed’s F-16, the T-50’s lighter weight and larger wings took out the Falcon’s infamous bouncy landing. The T-50’s flight controls also mirrored the F-16, though the trainer has a smoother G-onset and roll that make the ride more comfortable for novice pilots.

Before submitting their proposal to the USAF, Lockheed and KAI completed testing on an existing T-50 that they say will help push the programme’s replacement timeline to the left. Pilots in Korea also cleared an addition to the T-X1, the Dorsal Air Refueling Tank (DART). While Boeing’s offering touts a built-in refuelling capability, Lockheed’s DART comes as an addition, with about 350lb (160kg) of weight but close to no drag, according to Lockheed. The refuelling system still requires a tanker clearance, which Lockheed decided would be cost prohibitive to conduct without the T-X contract.

Within the T-X competition, industry is competing for the ejection seat for the trainer. Lockheed’s proposal aircraft will include an ejection seat with simplified straps and lap belt. The company uses a Martin-Baker seat for the F-35 but is exploring all options for the trainer.

“The TX requirements are more stringent than any other airplane ever from an ejection seat perspective,” Torgerson says. “They admit they made it harder than the F-35 requirements.”

As Boeing and Lockheed trade barbs over the trainer recapitalisation, Leonardo is pitching its T-100 as a ready competitor in the US competition. The company has at least leveraged a piece of American aviation nostalgia with its decision to assemble the T-100 in Tuskegee, Alabama. The proposed facility at Moton Field once hosted the school that trained black fighter pilots, the Tuskegee airmen, for the US Army Air Corps in World War II. Leonardo would invest $200 million to build a final assembly facility for the M-346 Master derivative, the company announced in March.