Earlier this year, after Lockheed Martin failed to win the contract for the United States Air Force’s sixth-generation fighter at the center of the Next Generation Air Dominance (NGAD) program, the aerospace giant announced it would pivot by developing a more advanced F-35 Lightning II. The prospective upgraded version would integrate technology developed for its sixth-generation prototype, serving as a bridge from the fifth-generation F-35 to the Boeing F-47, the aircraft produced under the NGAD contract.

President Donald Trump, who praised the capabilities of the F-47, has recently suggested that Lockheed Martin could even produce a twin-engine F-35 variant, which he proceeded to dub the “F-55.”

“It’s going to be also with two engines because the F-35 has a single engine. I don’t like single engines,” Trump explained at the time.

However, aviation analysts quickly dismissed that such a transformation could be easily accomplished. For one, it would require a major redesign to the F-35, one that would take years to achieve. Moreover, with twin engines, producing a short takeoff and vertical landing (STOVL) variant with a lift fan would be all but impossible without significant changes.

Last week, a source with knowledge of aerospace engines further criticized any efforts by Lockheed Martin to double down on the F-35, especially if it meant doubling the engines.

“To make a twin-engine jet from the F-35, you’d need to completely redesign the fuselage, wing, tail, and stealth shaping,” the source told

© The National Interest