The US Air Force is re-assessing its numbers of so-called fifth-generation fighters, although it is still not backing off its commitment to buy 1,763 Lockheed Martin F-35As over the next 35 years.

The USAF now plans to operate about 185 Lockheed F-22As along with the F-35A fleet, amounting to a combined force of nearly 1,950 fighters with the stealth, manouevrability and advanced sensors that meet the service's definition for fifth-generation capability.

However, as cost increases and the budget reductions lowered planned orders of F-22As from 750 to less than 200 over the last 20 years, some have rasised questions about the USAF's ability to afford the full F-35A fleet size.

"As we look to our fighter force of the future as we move to the fifth generation, we are doing an assessment of that that number is," Lieutenant General Herbert "Hawk" Carlisle, deputy chief of operations, plans and requirements, told Flightglobal on the sidelines of an Air Force Association event.

Carlisle added that the USAF remains committed to buying 1,763 F-35As, but will also continue evaluating the overall number as time passes.

 F-35 JSF maintenance

 ©Lockheed Martin

"We stilll believe we need that many in the out-years," he said. "But we have time to continue to evaluate that as we move forward."

The USAF has postponed purchases of hundreds of F-35As beyond the next five-year period as technical problems have delayed testing and manufacturing schedules. The service's lateest budget proposal calls for buying only 172 F-35As through Fiscal 2017.

Carlisle's remarks about fleet size came after the veteran Boeing F-15C Eagle pilot and future commander of Pacific Air Forces offered a defence of the USAF's heavy investments in fifth-generation fighter technology.

Despite the cost increases and technical glitches expereinced by both F-22 and F-35 programmed, the USAF expects to operate the most capable fighters in the world. While the F-22 is an air-to-air specialist and the F-35 is designed for ground attack, Carlisle said both fighters still have no equal.

"The F-22 does better air-to-groud than anybody than the F-35," Carlisle said, "and the F-35 does air-to-air better than anything in the world except the F-22."

Afterward, Carlisle acknowledged to reporters that maintaining sufficient quantities of fighters is still an important factor even as the capabilities of each fighter increase.

"There is a physical limitation. You can only be in so many places," he said. "If you have to [operate combat air patrols] in a South China Sea scenario or some Iranian/Arabian Gulf scenario --whatever those are -- there is a quantity requirement."

Source: Flight International