WASHINGTON — Lockheed Martin this week revealed its Skunk Works proposal for a next-generation U-2 spy plane, a tactical reconnaissance aircraft called "TR-X."

As the Air Force looks to retire Lockheed's U-2 Dragon Lady in 2019, the company has come up with a next-generation replacement, Scott Winstead, strategic business manager for the U-2 program, told reporters on Monday at the Air Force Association's annual conference. Lockheed is still shaping the capabilities of TR-X, a high-altitude aircraft that is designed to conduct intelligence, surveillance and reconnaissance missions for decades to come.

TR-X will look very much like the U-2, taking advantage of the spy plane's General Electric F118 engine and with a similar modular payload capability. The concept is for a low-observable aircraft designed to fly at 70,000 feet, Winstead said.

Lockheed is looking into increased power and cooling to accommodate new sensors, electronic warfare suites, and a more advanced communications system with the ability to communicate with both fourth and fifth-generation fighter jets, Winstead said. The plane will comply with the Air Force's Open Mission Systems standards to keep up with technology advances, and may even employ offensive and defensive laser weapons in future.

While Lockheed pitched the TR-X to reporters here on Monday, the team has yet to brief the Air Force on the new concept, Lt. Gen. Robert Otto, deputy chief of staff for ISR, told reporters later that day.

For now, the Air Force is not committing to TR-X or any other next-generation U-2 concept, Otto said. The service just doesn't have the resources right now to maintain two high-altitude ISR platforms — the U-2 and Northrop Grumman's Global Hawk — as well as develop a new concept.

"Both U-2 and Global Hawk have legs well into the late 20s, I think you are into the 30s, maybe into the 40s in terms of how long those platforms could last before they are deemed not airworthy," Otto said, noting that the Air Force is upgrading the Global Hawk with new capabilities. "The issue for me is we don't have the money to afford two high-altitude ISR platforms."

A next-generation high-altitude ISR platform would need to be stealthy to penetrate contested air space, and stealth historically drives huge cost increases, Otto emphasized.

Otto likened the U-2 debate to the Air Force's controversial attempt to retire the A-10 close-attack aircraft.

"That was the same thought behind the A-10 — not that we don't love the A-10, we do, we just can't afford it," Otto said. "So similarly I think with the Global Hawk and the U-2 is, you know, we love the U-2, we can't afford both platforms."

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