WASHINGTON -- A showdown might soon settle one of the U.S. military's biggest air power controversies.
The high-tech and expensive F-35 Joint Strike Fighter will face off in upcoming testing with the Air Force's aging close-air-support stalwart, the A-10 Thunderbolt II, the director of the Defense Department operational test and evaluation office said Tuesday.
The battlefield comparison "makes common sense" and will pit the two airframes against each other in a variety of war scenarios this year, Michael Gilmore said during Senate testimony.
The department is in the midst of developing the F-35 -- the most expensive procurement program in its history -- to take over the A-10's four-decade-old role of supporting ground forces with its titanium armor and powerful nose cannon. But the move is opposed by infantry troops and members of Congress who believe the A-10 is uniquely capable of saving lives on the battlefield.
"To me, comparison testing just makes common sense," Gilmore said. "If you're spending a lot of money to get improved capability, that's the easiest way to demonstrate it is to do a rigorous comparison test."
The F-35 is being touted as the most advanced fighter jet in the world, a jack of all trades intended to take over a variety of roles from other aircraft, including the A-10 and the F-16 fighter jet. The Marine Corps declared its variant of the aircraft combat-ready last summer and the Air Force plans to complete its testing this year.
But its 15-year procurement quest has been riddled with delays, scandals and technical glitches. The F-35 program office is now trying to overcome a problem with the aircraft's software system that caused the radar to blink out and require rebooting during flight.
The program, including production and maintenance, could ultimately cost taxpayers about $1.4 trillion and, despite promises of air dominance, the F-35 remains untested in real combat -- especially the type typically waged by the 1970s-era Warthog.
The A-10, on the other hand, is now deployed in the war against the Islamic State group in Iraq and Syria and has built a devoted following among combat veterans. But the airframe is aging and the Air Force now plans to retire the Warthog and unshoulder the costs of upkeep by 2022.
Gilmore said the two aircraft will face off on close air support and combat search and rescue, as well as other missions.
"We're going to do it under all the circumstances that we see CAS [close air support] conducted, including under high-threat conditions in which we expect F-35 will have an advantage and other conditions requiring loitering on the target, low-altitude operations and so-forth," Gilmore told the Senate Armed Services Committee.
On paper, the F-35 faces some apparent challenges because it does not carry the firepower of the Gatling-style nose cannon or the ability to fly over targets for a long period of time compared to the Warthog.
"There are a lot of arguments that ensue over which aircraft might have the advantage, the A-10 or the F-35, but that is what the comparison test is meant to show us," Gilmore said.
The controversy over whether the two aircraft will have similar capabilities became murkier in March when Air Force Chief of Staff Gen. Mark Welsh testified to the Senate committee that the F-35 would not replace the A-10.
During the hearing Tuesday, Sen. Kelly Ayotte, R-N.H., said the general's earlier testimony appeared to contradict statements on the fighter jet program's website and its longtime aim to take over the Warthog responsibilities.
The Pentagon's top weapons buyer denied any contradiction.
"Both statements are correct. We will in fact replace the A-10s with F-35s, that is the plan," said Frank Kendall, under secretary of defense for acquisition, technology and logistics.
But Kendall said there should be no expectation that the F-35 will perform in the same way as the A-10 on the battlefield.
"The A-10 was designed to be low and slow and close to the targets it was engaging, relatively speaking," he said. "We will not use the F-35 in the same way as the A-10, so it will perform the mission very differently."