Two months after greenlighting the F-47 next-generation fighter jet, President Donald Trump made headlines again on May 15 with a surprising new proposal: a twin-engine variant of the F-35 Lightning II stealth fighter. Dubbed the “F-55,” this hypothetical aircraft would represent a fundamental shift in the design and development philosophy behind one of the most iconic jets in U.S. military history.
Speaking at a press conference in Doha, Qatar, Trump outlined his vision. The venue, originally intended to announce a commercial aviation deal between Boeing, GE Aerospace, and Qatar Airways, became the stage for a potentially game-changing military announcement.
“We’re doing an upgrade—a simple upgrade—but we’re also doing an F-55,” Trump said. “I’m going to call it an F-55. That’s going to be a substantial upgrade… with two engines because the F-35 has a single engine. I don’t like single engines.”
The comment sent ripples through the defense and aerospace communities. For the first time, a U.S. president has suggested fundamentally altering the F-35’s design, a project that has taken decades, billions of dollars, and massive inter-service coordination to build and deploy.
The F-35 program, built around the idea of commonality across three service branches—the Air Force (F-35A), Navy (F-35C), and Marine Corps (F-35B)—was deliberately designed as a single-engine platform to reduce cost and weight while maintaining stealth and versatility. Its single Pratt & Whitney F135 engine is among the most powerful jet engines ever built, delivering over 40,000 pounds of thrust.
Trump’s argument rests on a perceived safety and performance advantage of twin-engine designs. He referenced that “if one engine fails, the plane can still return.” In military aviation, this is not a trivial concern, especially for missions over hostile territory or long stretches of ocean.
Analysts agree that a second engine could improve thrust-to-weight ratios, allow for greater payload capacity, and extend range. But the downsides are formidable. The redesign effort would be so extensive that some experts argue it would essentially create an entirely new aircraft—undermining the logic of calling it a “variant.”
Though there is no official program yet named the F-55, Trump’s remarks have breathed life into a previously fringe idea. Creating a twin-engine variant of the F-35 would not only require an overhaul of the airframe, flight control systems, and internal layout, but it would also complicate maintenance, training, and production lines.
More critically, it could disrupt the unique tri-service compatibility that made the F-35 an unprecedented multi-branch success. The Marine Corps’ F-35B, for example, has short takeoff and vertical landing (STOVL) capabilities. Reconfiguring that to accommodate two engines is not just impractical—it’s likely impossible.
Trump’s announcement has rekindled concerns about cost overruns. The F-35 program is already the most expensive weapons program in Pentagon history. A recent report from the U.S. Government Accountability Office estimated the total life-cycle cost at over $2 trillion. Adding another aircraft into the mix—especially one that deviates from the established design—would likely send budgets skyrocketing.
“The F-55 would not just be an evolution. It would be a parallel aircraft that adds complexity to procurement, logistics, and operations,” said Dr. Michael Wertheimer, a senior fellow at the Center for Strategic and Budgetary Assessments.
Wertheimer noted that one of the selling points of the original Joint Strike Fighter program was that different military branches could share a common platform. “A new design like the F-55 would chip away at that commonality and reduce cost-efficiency.”
Some defense insiders view the F-55 as a political move—a way to reassert U.S. aerospace innovation during a period of growing international competition. Trump’s earlier announcement of the F-47—a new stealth fighter developed by Boeing and expected to be operational by 2029—was seen as an effort to leapfrog to sixth-generation capabilities.
With China flying prototypes of sixth-generation fighters and Russia testing hypersonic air-to-air missiles, the U.S. is under pressure to maintain its edge. However, critics question whether pouring resources into a second fifth-generation aircraft is the right way forward.
Elon Musk, who now heads the Department of Government Efficiency (DOGE), recently criticized the F-35 as “expensive, complex, and borderline obsolete in the age of autonomous warfare.” His comments were echoed by others advocating a greater focus on unmanned systems and next-gen technologies like AI-assisted dogfighting, swarming drones, and advanced electronic warfare.
Trump’s remarks didn’t stop at the F-55. He also brought up an upgraded F-22 Raptor, calling it the “F-22 Super.”
“The F-22 is the most beautiful fighter in the world,” Trump said. “We’re going to be doing an F-22 Super, a very modern version of that aircraft.”
Unlike the F-35, the F-22 is no longer in production. Only about 180 operational Raptors remain, and the Air Force has been focused on preserving and modernizing them through selective upgrades. These include improved radar systems, stealth-enhanced fuel tanks, and advanced infrared search and track (IRST) sensors.
But an “F-22 Super” would presumably go well beyond that—possibly including structural redesigns, new engines, or sixth-generation technology integrations. Still, details remain vague.
Trump’s F-55 announcement could also reopen a fierce competition between Boeing and Lockheed Martin. Boeing is already leading the F-47 Next-Generation Air Dominance (NGAD) fighter, widely seen as a sixth-gen aircraft. If Lockheed Martin is tapped to develop the F-55, the result would be two overlapping, potentially competing fifth-gen+ programs.
Lockheed Martin responded diplomatically to Trump’s remarks:
“We thank President Trump for his support of the F-35 and F-22 and will continue to work closely with the Administration to realize its vision for air dominance.”
However, the aerospace industry is reading between the lines. If Lockheed can secure a new project like the F-55, it would compensate for its recent loss in the NGAD race and potentially reposition it at the forefront of future fighter development.
The timing of Trump’s announcement may also be influenced by recent battlefield revelations. According to The New York Times, a U.S. F-35 and several F-16s were nearly hit by Houthi missiles over Yemen. The report claimed that “several American F-16s and an F-35 fighter jet were nearly struck by Houthi air defenses.”
That incident has fueled criticism that even stealth aircraft are increasingly vulnerable to modern radar and missile systems. If a Houthi-operated SAM system can lock onto an F-35, then more sophisticated Chinese or Russian systems could do far worse.
It’s a humbling moment for the Pentagon and underscores the need to rethink future survivability strategies—not just in terms of stealth but in electronic warfare, redundancy, and strategic doctrine.
One lingering question is whether the F-55 is a technological leap—or a costly detour. Lockheed Martin CEO Jim Taiclet recently suggested that the F-35 could be upgraded with 80% of NGAD (Next-Gen Air Dominance) technology for “half the cost.” That sounds impressive, but Taiclet did not mention a twin-engine option.
The F-55 idea, on the other hand, seems to be a departure from both the NGAD roadmap and the existing F-35 modernization path (including Block 4 and TR-3 upgrades currently being tested). Critics worry that starting a new airframe design so late in the fifth-generation timeline might cannibalize sixth-generation development.
The F-55 is not yet a program of record. No RFPs have been released, no budget allocations made, and no design studies confirmed. But Trump’s ability to turn a suggestion into a full-fledged policy initiative is well documented.
Supporters view the F-55 idea as a bold, necessary rethink of America’s air dominance strategy. Skeptics see it as an expensive distraction that risks compromising current programs while delaying the pivot to sixth-gen platforms.
Either way, the defense community is paying attention.
As the Pentagon grapples with budget caps, evolving threats, and rapid technological change, Trump’s F-55 proposal may be the first spark in a new—and possibly controversial—chapter in American fighter jet development.
