Lightweight Turbogenerator for VTOL UAV

The Navy operates Vertical Take-Off and Landing (VTOL) Unmanned Aerial Systems (UAS) from ships to provide a Beyond Line-Of-Sight (BLOS) Intelligence, Surveillance and Reconnaissance (ISR) capability.   An example is the MQ-8C Fire Scout, which is a helicopter UAV based on the Bell 407 airframe.  Helicopters require propulsion systems that meet the takeoff hover power demand and that are relatively inefficiency during horizontal flight.  A VTOL UAS that can takeoff vertically, then transition to horizontal flight like a fixed-wing aircraft, has the potential to be significantly more efficient than a helicopter.  Concepts for VTOL UAS’s with this capability, such as concepts in the DARPA ANCILLARY program, typically use distributed electric propulsors, which I turn require a generator to supply electric power.  This program seeks to develop a novel lightweight turbogenerator for future Navy VTOL UAS’s.  Creare and UAV Turbines have been developing a 50 hp recuperated turbogenerator for a ground power application. This engine has efficient turbomachines, generator, and recuperator, and easily meets the SFC requirements for this topic. The main challenge is in the specific power requirement. Our approach involves adapting the existing engine core to reduce weight through the use of gas bearing and integrated high-efficiency High-Speed Starter Generator (HSSG).  In Phase I we developed a conceptual design for the turbogenerator, which we call a Monarch 5 VTOL.  Our baseline design meets the Navy’s requirements for SFC (< 3 lb/hp-hr), specific power (> 2 hp/lb), VTOL and marine compatibility.  In Phase II, we will develop and test a fully integrated turbogenerator. The turbogenerator developed under this program will be commercialized as a UAV Turbines product for direct sale to Navy programs or other commercial applications.