ORLANDO, Fla. – Despite speculation that parameters for the Air Force's T-X trainer are still up in the air, top officials say there will be no more changes to the program requirements.

The Air Force's requirements for 350 T-X jets to replace the service's aging T-38 trainer fleet are pretty much set, according to Brig. Gen. Andrew Croft, director of plans, programs, requirements and assessments for Air Education and Training Command. Although a formal request for proposals will not be released until later this year, the requirements will likely hold steady in part to control cost growth, officials said late last month at the Air Force Association's Air Warfare Symposium.

"As far as changes go, there's real stability in the T-X program, none of the requirements have changed," AETC commander Lt. Gen. Darryl Roberson told reporters Feb. 25. "That's one of the premises of how we're approaching this program as well. … We are trying as hard as we can to stick to requirements and not change them because as soon as you do, now the cost goes up."

As the Air Force prepares to release the official RFP, a field of at least four industry teams is shaping up to compete for the contract. Raytheon, Finmeccanica and CAE will offer the T-100; Lockheed Martin and Korea Aerospace Industries have teamed up for the T-50A; meanwhile a pair of clean-sheet designs is being put forth by a Boeing/Saab team and a Northrop Grumman-led coalition that includes BAE Systems and L2.

Textron AirLand had hoped to offer its Scorpion design, or a modified version of the plane, for the T-X competition. But last month, president Bill Anderson said the company had ruled out offering Scorpion and also determined that developing a clean-sheet design for the T-X requirements as they exist today would be cost-prohibitive for the company.

If the Air Force decides to go in a different direction with the requirements, Textron AirLand may still offer the Scorpion or a clean-sheet design, Anderson said. But as Roberson and Croft have indicated the T-X requirements will not change in any significant way, Textron AirLand may be out of the running.

The Air Force has identified 18 key attributes for the next-generation plane, Croft told Defense News in a Feb. 25 interview, including: sustained G; angle of attack; night training; system integration; and the ability to manage a fifth-generation cockpit with vast amounts of sensor input, for instance the F-35 and the F-22.

But just as important as the airframe is the integrated ground-based training system to support training of fifth-generation pilots, Croft said.

"There is so much more to this airplane, and it's really the integration of the system with the ground-based training system," Croft said. "We tend to focus on the machine and the shiny object, which is the airplane, and it's more than that, we're not just replacing iron for iron."

As demand grows for the Air Force's fleet of fighter aircraft, simulation and ground-based pilot training becomes key, Croft said. The Air Force wants to take advantage of advances in simulation, particularly improvements in visual fidelity, which enables pilots to do more of their training on the ground before actually flying a plane. For example, AETC has linked simulators together so two pilots sitting in simulators can "fly" in formation with each other.

"If we can take some of the fifth-gen training out of the fifth-gen airplanes and put them into the T-X, that will save us quite a bit of money and then we can concentrate on maintaining the fifth-gen airplanes for combat ops instead of for training," Croft said. "And actually, we increase the capability of the pilot, too."

The Air Force likely won't hold any additional industry days before the RFP is released, but the service continues to engage with industry on the Federal Business Opportunities website, Croft said. The program office has already fielded close to 300 questions from various industry partners, he noted, a constant dialogue that the Air Force hopes will lead to a better product in the long run.

After the RFP is released this year, the Air Force will award a contract by the end of calendar year 2017, Croft said. T-X will reach initial operational capability in 2024, and full operational capability in 2032. However, it is possible the Air Force and industry team could speed up that timeline because the existing airframes are so old, he said.

"Some of the T-38s will reach 70 years on that airframe by the time we finally replace them, so any year we can go beyond that is just an airframe that doesn't meet our requirements, it's older, it's harder to maintain and it costs us more," Croft said. "So that's why there's such a pressure to get this done and try to not slip the timeline, but again it's all dependent on the fiscal environment."

Email: lseligman@defensenews.com

Twitter: @laraseligman

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