Precision at Speed: Turbojet Propulsion in the Age of Autonomous Defense

We sat down with Erin Durham, CEO of PBS Aerospace, to explore how the company is advancing turbojet technology to meet the demands of high-speed ISR, counter-UAS, and swarm-enabled platforms. Durham shares insights into PBS’s approach to modular integration, lifecycle reliability, and regulatory trust—along with a look at how collaborations like the Crossbow platform are accelerating time-to-market for next-generation UAVs.

From their new facility in Roswell, Georgia to their expanding R&D partnerships, PBS Aerospace is positioning itself as a key enabler of autonomous flight. This conversation offers a behind-the-scenes look at how propulsion strategy intersects with mission readiness, export compliance, and the future of intelligent unmanned systems.

Aerospace Trends: How do you define scalability in the context of unmanned systems, and where do turbojets fit into that vision?

Erin Durham: At PBS Aerospace, scalability isn’t just about producing more engines; it’s about enabling our partners to think bigger. Turbojet engines offer a unique intersection of cost and performance that enable affordable and precise counter-UAS and swarming platforms.

AT: What are the most common misconceptions about turbojet propulsion in today’s UAV market?

ED: One of the biggest misconceptions is that turbojets are inefficient or too complex for smaller UAVs. The reality is that our turbojets are highly reliable, compact, and cost-effective, particularly when mission speed, climb rate, or responsiveness are critical. We build our engines like high-quality toasters, which are very reliable and scale easily at high manufacturing volumes.

AT: What distinguishes PBS’s TJ100 and TJ200 engines from other compact propulsion systems?

ED: PBS’s entire turbojet portfolio offers the best Specific Fuel Consumption (think miles per gallon in automobiles) and Thrust-to-Weight ratio in the marketplace. PBS engines are known throughout the industry for high reliability and a commitment to meet published technical specifications at an affordable price.

AT: How do you approach modularity and integration across diverse UAV platforms?

ED: We design with adaptability at the forefront. Our engines can integrate with a wide range of fuselage geometries and fuel systems, and our digital control interface allows seamless pairing with different avionics and autonomy stacks. We pride ourselves on having great customer integration support that can enable customers to have extraordinarily short times to flight testing.

AT: Which mission profiles are driving demand for turbojet-powered UAVs today?

ED: We’re seeing growth in high-speed ISR, electronic warfare, target drone, swarm munitions, and counter-UAS. These missions demand long ranges, speed, and responsiveness to complete these types of missions. Nations investing in advanced deterrence and autonomy increasingly see turbojets as essential to next-generation defense architectures.

AT: Can you share insights from recent collaborations, such as the Crossbow platform?

ED: Crossbow is a great example of what happens when innovative airframe design meets mature propulsion units. The TJ100 has proven reliability that enabled these customers to market a new platform at an affordable price and a quick timeline. Collaborations like this validate our approach, supporting customers from concept through certification, not just selling an engine.

AT: How is PBS addressing maintenance, diagnostics, and lifecycle support for turbojet engines?

ED: Operational readiness at PBS starts on the test stand. Every engine is hot-fired and acceptance-tested before it ships, with performance data recorded as the baseline for the life of the product. That discipline carries into the field: our engines are engineered to deliver a dependable first-start even after extended storage—months or years—so crews can count on them when the mission window opens. The philosophy is simple: prove it before it leaves, and make sure it lights when it matters.

AT: What feedback have you received from operators managing turbojet-powered fleets?

ED: Operators consistently highlight reliability and ease of integration. They also appreciate the consistency between our Czech and U.S. support teams—every engine comes with a service structure that mirrors manned aviation, but scaled to unmanned logistics realities.

AT: How does PBS navigate certification and export compliance across different markets?

ED: PBS Group has operated in certified aviation and defense environments for decades, so we are very used to these regulations. On the export side, we work closely with U.S. and European regulators to ensure full compliance with ITAR and EAR classifications, and it helps that our engines are sold in both commercial and defense applications (dual use). Having dual operational bases in the Czech Republic and the United States allows us to navigate both ecosystems with precision.

AT: What role does propulsion play in building trust with regulators and defense partners?

ED: Jet propulsion products are hard to design and manufacture. When your engine manufacturer has decades of traceable production, flight hours, and certified processes, it builds trust at every level—from procurement to operational command. That’s the standard we maintain, and it’s why PBS engines power so many assets worldwide.

AT: How do you see turbojet propulsion evolving to support autonomous and intelligent unmanned systems?

ED: As autonomy at scale concepts advance, propulsion has to become more efficient, both in cost and technical performance. We’re continuously investing in ways to make our turbojets more cost-effective with better technical performance to enable these systems to operate with more assets at more speed and higher altitudes.

AT: What’s next for PBS Aerospace in terms of innovation and strategic growth?

ED: Our focus is on scaling production in the U.S. and expanding R&D partnerships that bridge defense and academia. The new Roswell, Georgia facility positions us to increase capacity and deepen collaboration with the U.S. Air Force, Navy, and emerging UAV manufacturers. We’re also expanding into hybrid propulsion research. The future of flight will require a fusion of endurance, speed, and intelligent control, and PBS plans to enable these next generation platforms.