The Solid Liquid Integrated Cycle (SLICE) rocket engine uses a solid propellant gas generator for the fuel and a liquid oxidizer. The propellants are combusted in an array of small thrusters with the exhaust expanded on an aerospike nozzle. SLICE reduces cost by using safe, easy to handle propellants and by taking advantage of economy of scale in the manufacturing of the thrusters. The objective of this effort was to mature SLICE propulsion technology in order to prepare it for use on NASA Armstrong Flight Research Center’s Towed Glider Air Launched System (TGALS).

Exquadrum’s mission on the DARPA Operational Fires (OpFires) program was to develop and demonstrate a highly innovative rocket booster to launch hypersonic boost glide weapons to penetrate modern enemy air defenses and rapidly and precisely engage critical time sensitive targets. DARPA awarded Exquadrum a $15.1 million Prime Contract in September 2018. Exquadrum partnered with key subcontractor, Dynetics of Huntsville, Alabama, in order to achieve DARPA’s challenging technical and programmatic objectives.

Three weeks after contract award, Exquadrum began hot-fire, static testing of TopFuel rocket propulsion technology, which uses a tactical, liquid monopropellant to augment and control a solid rocket motor enabling a wide range of throttleabilty and energy management capability to meet OpFires mission objectives. By the time that technical work on the OpFires contract ended in June 2020, Exquadrum had conducted over 200 hot-fire, TopFuel rocket tests. Exquadrum was the only one of the three OpFires Prime Contractors to conduct a full-scale, full-duration static test within the first year after contract award.

In June 2020, Exquadrum conducted its final OpFires rocket test known as the Technology Maturation Event 2A (TME2A). TME2A was a second full-scale, full-duration (90+ second) static test, but used flight-ready solid propellant and liquid monopropellant. The hardware was primarily flight-weight, but the stage structure/case was heavy-weight. TopFuel rocket propulsion technology is now ready to transition to a host of advanced flight applications from hypersonics to traditional rocket booster systems.

DARPA Approved for Public Release the following materials about Exquadrum’s OpFires program:

• DARPA’s OpFires TME1 Press Release
• Exquadrum’s OpFires TME2A Press Release
• Photo of Exquadrum’s OpFires TME2A Test (see above)
• Accelerated-Time Video of Exquadrum’s OpFires TME2A Test
• Normal-Time Video of Exquadrum’s OpFires TME2A Test

The Low-Cost Turbopump for Expendable Launch Technology (LCTPA) program engineered and fabricated a low-cost turbopump for to meet the cost objectives of the XS-1 engine.

The Low-Cost Turbopump for Expendable Launch Technology (LCTPA) program engineered and fabricated a low-cost turbopump for to meet the cost objectives of the DARPA XS-1 vehicle engine. The turbopump is a “clean sheet” design for a 35k pound force engine and utilizes additive and traditional manufacturing technologies to reduce part count and machining time. The system is a single shaft liquid oxygen pump and liquid hydrogen pump driven by an expander cycle powered methane turbine.

Exquadrum conducted the Hybrid Upper Stage Booster (HUSB) program for NASA in order to develop a new technology called the Solid/Liquid Integrated Cycle Engine (SLICE).

The Hybrid Upper Stage Booster (HUSB) Phase II program achieved all of its objectives. The feasibility of the Solid/Liquid Integrated Cycle Engine (SLICE) propulsion concept has been decisively demonstrated. A gas-generator propellant designated as Exquadrazine 6514 was developed that is low cost, but has high performance. The propellant received a Department of Transportation (DOT) hazard classification of 1.4C, which is the safest possible rating for a formulation that is designated for use in rocket propulsion. The engine ignited readily and smoothly in all tests. Combustion was stable with smooth transients during throttling. The effort concluded with a test of three combustors operating from a single gas-generator with the exhaust exiting on a section of an aerospike nozzle.

The US Air Force named Exquadrum a “Designated Subcontractor” for the Heated and Mobile Munitions Employing Rockets (HAMMER)program and gave us the mission to develop a munition designed to thermally neutralize Chemical and Biological Weapons of Mass Destruction (WMD)

Many of Exquadrum’s earliest contracts were aimed at evolving solid rocket propellant technology to enable destruction of chemical and biological Weapons of Mass Destruction (WMD). Exquadrum’s exciting and successful technology was brought out into the open in 2008 when Wired magazine published a surprise article on our work entitled “Secret Rocket Balls Target WMD Bunkers.” Kinetic Fireball Incendiary mania began worldwide with graphics created and posted by fans. This new-found fame led the US Air Force to name Exquadrum a “Designated Subcontractor” for the Heated and Mobile Munitions Employing Rockets (HAMMER)program. HAMMER was a $21.6M program to create an air-dropped penetrator munition based on Exquadrum’s technology. The technology was successfully demonstrated at Dugway Proving Ground. Where is this technology today? Exquadrum can neither confirm nor deny…

Read More: https://www.wired.com/2008/11/secret-rocket-b/

Exquadrum developed an innovative, yet highly cost effective, approach to the fabrication of new arcjet heater segments for this research project. Segmented arcjet heaters support the critical development of hypersonic capabilities for the US DoD. Arcjet facilities reproduce thermal environments encountered during flight from Mach 8 to 20. Work completed on the program resulted in the award of US Patent 7,509,851 B1