Air Force sounds out industry on alternative F-15EX, F-16 engines

The Air Force wants new competitors to challenge Pratt & Whitney and GE Aerospace, betting that reviving the Cold War-era “Great Engine War” can fix a fighter engine industrial base plagued by delays and shortages.

The Air Force has launched a request for information seeking alternative engines for the F-15EX and F-16, challenging the decades-long duopoly held by Pratt & Whitney and GE Aerospace.

The multiyear acquisition initiative asks industry to compete for a program the government projects will require more than 180 engines a year by 2034, covering both U.S. Air Force purchases and sales to foreign allies. Companies have until Aug. 28 to respond.

The government says it wants to move away from legacy buying practices and instead push what it calls “industry-led technological evolution,” using the promise of high-volume, long-term contracts to get manufacturers to invest in expanded factories, updated tooling and more automation. Rather than picking a winner based on the lowest sticker price, officials say they will weigh total lifecycle costs, supply chain resilience and ease of maintenance — factors they argue matter more to keeping jets flying.

“The government will pursue a strategic competition requiring industry to innovate manufacturing and guarantee supply chain resiliency,” the request for information states. Officials said the evaluation will focus “on the total lifecycle cost of the engine, not just the initial purchase price.”

The push comes after what the government describes as a breakdown in the current supplier base. The request for information states that “the current industrial base has demonstrated significant challenges, including production delays, quality control issues, and critical obsolescence (i.e., diminishing manufacturing sources and material shortages) across key engine components.”

Those failures have already hit two of the military’s marquee programs. A Government Accountability Office report on the F-35 Lightning II found that “the engine contractor is still not delivering engines to contract specifications after nearly 20 years of production.” The B-52 Stratofortress modernization effort, meanwhile, has absorbed a roughly $3 billion cost increase and a delay of more than 15 months in reaching operational capability, according to a Government Accountability Office report released July 31. The watchdog attributed the setbacks to the Air Force pushing the engine replacement into production with minimal developmental flight testing.

Pratt & Whitney, which builds the F-35’s engine, responded to federal corrective-action demands in August 2024 with a plan to address supplier quality and expand capacity, though the Government Accountability Office found that Pratt & Whitney and Lockheed Martin collectively collected hundreds of millions of dollars in incentive fees even as deliveries fell further behind. Pratt & Whitney and GE Aerospace did not immediately respond to requests for comment on the government’s claims about industrial obsolescence.

The request for information also presses bidders on where the supply chain could break. It asks companies “what are the primary raw material constraints (e.g., specialized titanium/nickel alloys) or manufacturing process bottlenecks (e.g., advanced casting or forging capacity) that pose the highest risk to scaling up fighter engine production.” The question lands as China, which dominates global rare earth refining, has tightened export controls on the minerals — a constraint that reaches into advanced engine coatings and other high-temperature materials.

The strategy borrows directly from the Alternative Fighter Engine program of the 1970s and 1980s, known as the Great Engine War. Pratt & Whitney’s F100 engine, the sole powerplant for early F-15s and F-16s, suffered from a flaw called stall-stagnation that could cause catastrophic flameouts. The Air Force responded by funding General Electric to build a competing engine, over Pratt & Whitney’s objections. The competition split a 1984 contract between the two companies — 120 engines to GE for the F-16 fleet and 40 to Pratt & Whitney for the F-15 fleet — and produced the F110 and the modernized F100-PW-220, engines that have powered the fleet for four decades.

“The Great Engine War showed that competition is the clear way to go to optimize outcomes for the warfighter and U.S. taxpayers,” Sean Keith, executive product director for GE Aerospace’s F110, F101 and F118 engine programs, said in a company article marking the F110’s 40th year of production in December 2024. “The result of the competition was better engine performance at lower cost, with improved engine safety, maintainability, and durability.”

Not everyone is convinced a repeat will pay off. Defense analysts have argued that dual-source engine programs often fail to deliver real savings once reduced economies of scale, duplicate logistics and longer learning curves are factored in. Critics also note that fielding two engine designs means two sets of spares, tooling and technical data to sustain, and two production lines that can each develop their own defects. Pratt & Whitney has historically opposed government funding of rival engine programs as an unwarranted intervention in a settled market.

The stakes differ sharply between the two aircraft. The F-16, a single-engine fighter, has no backup if its powerplant fails — a vulnerability that made engine reliability a safety question as much as a cost question during the original Great Engine War. GE says its F110 powers about 70% of the latest-generation F-16C/D fleet. The Air Force stopped buying new F-16s for its own inventory years ago, but Lockheed Martin continues to build upgraded Block 70/72 jets, marketed as the F-16V, for foreign customers.

The F-15EX, built by Boeing and flown by twin F110-GE-129 engines, has taken on a bigger role. The Air Force has more than doubled its procurement target for the jet, to 267 aircraft from 129, positioning it as a heavily armed “missile truck” that can fire large volumes of munitions guided by data from stealthier jets like the F-35. Boeing markets the jet’s payload capacity — up to 29,500 pounds across 12 air-to-air and 15 air-to-ground stations — as its central advantage over both fifth-generation aircraft and Russian fourth-generation types. Critics counter that without stealth, the F-15EX would be far more exposed than fifth-generation jets in contested airspace defended by modern air defenses.

The engine competition also lands as the Air Force experiments with pairing crewed fighters with autonomous drones under its Collaborative Combat Aircraft program. Eglin Air Force Base’s 85th Test and Evaluation Squadron deployed an F-15EX to Kadena Air Base, Japan, on June 29 and flew it alongside an uncrewed MQ-28 Ghost Bat over the Philippine Sea during Exercise Valiant Shield, the Air Force said. The Ghost Bat is built by Boeing Defence Australia and is not part of the Air Force’s own Collaborative Combat Aircraft fleet. Because drones aren’t constrained by a pilot’s physiology, engineers say future uncrewed aircraft could pull far more extreme maneuvers.