This founder helped build SpaceX’s most powerful rocket engine. Now he’s building a ‘fighter jet for orbit’

Tom Markusic, the founder and CEO of Firefly Aerospace, is developing a revolutionary new rocket engine that could transform military space capabilities, building on his previous experience as a key engineer who helped develop SpaceX's powerful Raptor engine. The company, based in Cedar Park, Texas, is currently advancing this technology with the goal of creating what Markusic describes as a 'fighter jet for orbit' – a highly maneuverable, reusable spacecraft for the U.S. military. This development comes at a critical time as the Pentagon seeks to enhance its space-based defense systems and maintain technological superiority against growing competition from nations like China and Russia. The novel engine at the heart of this project represents a significant leap in propulsion technology. While specific technical details remain proprietary, industry analysts suggest it likely incorporates advanced materials and combustion cycles that enable greater efficiency, throttleability, and reusability than current systems. This engine is designed to power Firefly's proposed 'Space Utility Vehicle' (SUV), a spacecraft intended for a variety of missions including satellite servicing, reconnaissance, rapid deployment of payloads, and potentially even defensive operations in Earth orbit. The concept moves beyond traditional, single-use rockets toward a more dynamic and responsive space architecture. The potential military applications are vast and align with the U.S. Space Force's evolving doctrine. A reusable, agile orbital vehicle could inspect or repair friendly satellites, surveil or intercept adversarial spacecraft, and provide rapid tactical support. Markusic's background is pivotal to this endeavor; his direct involvement in creating the Raptor engine for SpaceX's Starship gives him unique insight into pushing the boundaries of rocket performance. Firefly's project underscores a broader shift in the defense space sector, where private companies with agile development cycles and innovative cultures are increasingly tasked with delivering next-generation capabilities that traditional defense contractors have been slower to produce.