“Evaluation and Design of EXOS-HVVR to Validate an RDRE to Meet DoD TRSA/ Hypersonic Testbed Objectives”

“The ultimate goal for us is to get to an enduring tactically responsive space capability by the 2025 or 2026 timeframe.”   Lt. Col. MacKenzie Birchenough, Space System Command.   “Rotating detonation rocket engines have the potential to make rockets lighter, faster, and more efficient. We’re looking forward to working with our industry partners to test this new technology that could ultimately propel humanity further into space.” Dr. Shawn Phillips, Chief of AFRL's Rocket Propulsion Division.   EXOS Aerospace is uniquely positioned to support the DoD in achieving these goals…..   RDREs have significant potential in both DoD and commercial applications but they are relatively unproven in flight configuration. Before risking an expensive full scale launch vehicle with this promising technology, it makes eminent sense to test on a subscale vehicle. EXOS Aerospace is proposing to use a subscale variant, the EXOS-HVVR, derived from a prior Terrestrial Lunar Lander Analog launch vehicle, Scorpius, that was successfully flown in the NASA-Northrop Grumman Lunar Lander competition. To achieve a Mass Ratio that will provide meaningful test times, EXOS proposes to use composite material technologies proven on the Reusable Hypersonic Launch Vehicle (RHLV) developed under an AFWERX/USAF SBIR, the BLK3. The BLK3 use carbon fiber composite technologies including linerless LOX compatible propellant tanks. This same technology was used for the fuel (Ethanol) tanks and the Helium pressurant tank. With integral skirts, these tanks were mated to the other structural components. This initial concept EXOS-HVVR has been designed to incorporate the same diameter tanks as the BLK3 to reduce both the engineering time and tooling costs. These are made by our sister company and the same technology, proven to TRL9, is incorporated in a Lunar Lander scheduled to land on the moon this year. The vehicle would also use the same Main Flight Computer, TTS, Roll Control, and Thrust Vector Control by engine gimbal that haves been proven on all our earlier vehicles. The EXOS Team has prior experience in incorporating novel propulsion technology into Lunar Lander style vehicles. The success of Scorpius led to NASA JSC awarding us a contract to build a scaled-up version of another lander, Pixel. This was the highly successful Project Morpheus which incorporated a NASA designed LOX-LCH4 engine and JPL furnished Autonomous Landing and Hazard Avoidance Technology (ALHAT). Moreover, the EXOS team was intimately involved in the development of the regulations related to “hanging hover tests” in conjunction with FAA AST. In fact, to this day, every EXOS Suborbital Sounding Rocket is tie-down tested (100% throttle) and hover tested to verify that the GNC and ACS are correctly configured. We have conducted dozens of such tests at our Caddo Mills Municipal Airport test center including free hover tests to 50-m and a boost to 1,200-m, freefall, reignite and powered landing back on the launch pad.