Hermeus will manufacture, assemble and deliver the engines under Pratt & Whitney’s production standards. The company plans to apply its rapid-build model while meeting established requirements for quality, safety and activation of the manufacturing site.
The agreement expands domestic capacity at a time when U.S. defense companies are seeking to increase production of established military systems. It also gives Hermeus direct control over propulsion manufacturing for its Quarterhorse aircraft.
“With more than 32 million flight hours, the F100 has earned its place as one of the world’s most trusted fighter engines,” said Jessica Villardi, vice president of Fighter & Mobility Programs at Pratt & Whitney. “By partnering with Hermeus, we are expanding U.S. production capacity to meet growing customer demand while delivering the proven dependability that defines the F100 engine.”
The F100 has powered U.S. Air Force F-15 and F-16 fighters for more than five decades. Engines from the family have accumulated more than 32 million flight hours.
Hermeus selected the F100 to power Quarterhorse, its uncrewed high-speed aircraft. Quarterhorse achieved supersonic flight earlier in 2026, becoming what the companies described as the world’s first privately developed uncrewed supersonic jet.
“Meeting future operational needs requires expanding America’s capacity to build the engines our warfighters rely on,” said Zach Shore, chief executive officer of Hermeus. “Pratt & Whitney built the standard for fighter propulsion.”
The license will make Hermeus the first vertically integrated aircraft manufacturer with in-house propulsion capacity to scale Quarterhorse, according to the company. It will also provide additional F100 manufacturing capacity for the broader U.S. defense industrial base.
“By becoming a licensed manufacturer of the F100, Hermeus expands domestic engine capacity for the broader defense industrial base and becomes the first vertically integrated airframer with the in-house propulsion capability required to scale Quarterhorse,” Shore said. The agreement links Pratt & Whitney’s established fighter-engine design with Hermeus’ production model for high-speed aircraft.
