WASHINGTON — General Dynamics Information Systems & Technology has withdrawn itself as the prime contractor on the T-100, the offering for the T-X trainer replacement program based on the Alenia Aermacchi M-346 design.

The decision, revealed in a company statement to Defense News, calls into question the future viability of the T-100 bid just a week after the Air Force released its final program requirements.

"General Dynamics Information Systems & Technology group reorganized its businesses effective the 1st of 2015," the statement reads, "and in the course of that reorganization has decided to discontinue pursuit of T-X as a prime contractor."

Whether General Dynamics will continue in its role as systems integrator for the offering is unclear. Spokespeople for Alenia could not be immediately reached for comment.

The T-X program, which will produce 350 advanced trainers for the US Air Force, is hotly contested, with four other competitors challenging the T-100. Whichever team wins the competition will also have a leg up on the lucrative training market overseas over the next three decades.

Including the T-100, there are five competitors aiming for the right to replace the aging T-38 fleet used by the service. That includes a pair of clean-sheet designs being put forth by a Boeing/Saab team and a Northrop Grumman-led coalition that includes BAE Systems and L-3; Textron AirLand's new Scorpion design; and the T-50, the Lockheed Martin/Korean Aerospace Industries offering.

It is unclear what Alenia's next move is, but the history of foreign companies acting as primes for US Air Force programs is not a kind one, notes Richard Aboulafia, an analyst with the Teal Group.

"I don't think anyone wants another Airbus situation," he said, referencing the European firm's failed attempt at winning the service's tanker contract. "It's conceivable, but unlikely."

With no clear prime alternatives for Alenia to turn to — Aboulafia mentioned Raytheon, but noted that it would not fit logically into their corporate focus — Alenia may face a choice: Roll the dice and go it alone, or pull the plug on their T-X ambitions.

Aboulafia called the turnaround of the T-100's fate "pretty extraordinary," given that at one point they looked like a frontrunner. But as the service continued to refine its requirements, some have questioned whether the T-100 can keep up.

"It's become clear the Air Force seems to be scaling up its T-X requirements," Aboulafia noted. "The T-100 might not be able to give them all they want."

A warning sign for the T-100 came in February, when Northrop Grumman disclosed that it was abandoning long-held plans to use the BAE Hawk Trainer as an offering in favor of a new clean-sheet design. Company executives have said that decision was made after the service requirements became more clear.

If the T-100 does withdraw, it may help the T-50 be competitive. The Lockheed/KAI offering would be the only proven design being used currently around the world, something executives for Lockheed clearly see as a selling point.

Twitter: @AaronMehta

Aaron Mehta was deputy editor and senior Pentagon correspondent for Defense News, covering policy, strategy and acquisition at the highest levels of the Defense Department and its international partners.

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