Sierra Nevada Corporation (SNC) reached a major milestone in the advancement of hypersonic propulsion with its patented VORTEX engine, advancing to the next phase of the U.S. Defense Advanced Research Projects Agency’s (DARPA) Operational Fires (OpFires) program, the company announced.
Through OpFires, SNC is extending its hybrid VORTEX engine capabilities to advanced, deep throttling, restartable propulsion systems. The system utilizes benign solid fuel with a liquid oxidizer, both of which are storable on Earth and in space. Recent testing shows positive results in being able to package significant energy into a small volume that will have the ability for deep throttling and smooth restart capabilities on command.
“The VORTEX flows integrated into the hybrid significantly improves performance of the hybrid engine” said Dr. Marty Chiaverini, director of Propulsion Systems at SNC.
“This program opens up a new market for SNC for preplanned or on-demand propulsion control capabilities that are applicable to both military and beyond Earth orbit propulsion capabilities,” said Tom Crabb, vice president of SNC’s Propulsion & Environmental Systems business unit. “Deep throttling and restart capabilities expand the tools for smart and unpredictable trajectories for various vehicles and systems.”
The first two phases of DARPA’s OpFires program focus on the propulsion technologies required to deliver diverse payloads to a variety of ranges. Since the Phase 1 contract award, SNC has made critical discoveries in advanced rocket motor technology for the OpFires upper stage, completing more than 30 motor trials from subscale through full size. SNC hopes to demonstrate these engines in flight and offer the engines to new, promising vehicle systems.
DARPA OpFires Program
DARPA’s OpFires program aims to develop and demonstrate a novel ground-launched missile system equipped with hypersonic tactical boost glide vehicle that can penetrate modern enemy air defenses and rapidly and precisely engage critical time-sensitive targets in contested environments.
The first two phases of the program focus on the propulsion technologies required to deliver diverse payloads a variety of ranges.
Phase 1 of the program was a 12-month effort focused on early development and demonstration of booster solutions that provide variable thrust propulsion across robust operational parameters in large tactical missiles. The Phase 1 contracts were awarded to Aerojet Rocketdyne, Exquadrum, and Sierra Nevada Corporation (SNC) in 2018.
Since the Phase 1 contract award, the three companies have made critical discoveries in advanced rocket motor technology for the OpFires upper stage, completing more than 30 motor trials from subscale through full size. These advances put the program on track for booster critical design review in late 2020.
Exquadrum completed a full-scale, full-duration test fire on Sept. 19, 2019, which marked the performer’s culminating event for OpFires Phase 1. SNC completed its Phase 1 testing in October, and Aerojet Rocketdyne completed six subscale tests in August.
The OpFires program reached a major program milestone in late 2019 with the completion of the booster preliminary design review of the two-stage tactical missile system. Phase 2 of the OpFires program will mature designs and demonstrate performance with hot/static fire tests targeted for late 2020.
Phase 3 of the OpFires program will focus on weapon system integration and aims to develop an operational system design leveraging propulsion systems concepts developed under the first two phases of the program.
Lockheed Martin Missiles and Fire Control is leading the integration effort for the third phase of the program. Phase 3 will conclude with integrated end-to-end flight tests scheduled to begin in 2022.