Opinion: Making Satellite Launches More Sustainable

Globally, there’s a forecast for up to 70,000 satellites to be launched by 2030. The SpaceX Falcon 9 is polluting the atmosphere with over 425 metric tonnes of CO2 emissions per launch — the equivalent of 395 transatlantic flights. By using green hydrogen as the fuel for a fifth-generation SPARTAN scramjet engine, Hypersonix engines emit only water vapour. Hydrogen also has other fantastic characteristics; it has a much higher ISP or thrust than other fuels, therefore flying at higher speeds. The Hypersonix SPARTAN scramjet engine flies at Mach 5 up to Mach 12 — the fastest way of flying through the atmosphere.

Various technological evolutions have helped along the way. One is low-cost access to computing power, which is necessary to not only know how a vehicle flies, but also to determine how they’re affected by heat in certain places.

The second is the development of high temperature ceramic matrix composites. In March 2022, Hypersonix, the University of Southern Queensland, Romar Engineering, and LSM Advanced Composites were jointly awarded a Cooperative Research Centres Projects (CRC-P) government grant of $2.95 million for the world’s first reusable hypersonic UAV project. The project, titled ‘DART CMP Airframe — a reusable hypersonic platform’, is an unmanned aerial vehicle (UAV) that can travel at hypersonic speeds up to Mach 12 and is powered by the SPARTAN hydrogen-fuelled scramjet engine. This project will deliver a new sovereign manufacturing capability for high temperature oxide-oxide ceramic matrix composites, with deliverables including a complete UAV airframe with a composite aeroshell, aerodynamic control surfaces, flight avionics, and a hydrogen fuel system.

The third evolution comes in the form of a rapidly growing market for satellite launches — a market Hypersonix is poised to tackle with its ability to launch frequently to any orbit within Lower Earth Orbit (LEO) from just one launch site, and a vehicle (Delta Vos) that is reusable hundreds of times over. Instead of ‘launching’ small satellites to space, Hypersonix ‘flies’ small satellites to space with winged vehicles that can be likened to an aircraft rather than a rocket.

With an ambitious and exciting plan to build three vehicles in three years starting with a technology demonstrator called DART AE, global interest in Hypersonix has grown. Key factors that will be demonstrated by DART AE include scalability of manufacturing, reliability, cost effectiveness and high cadence of manufacture, enabling multiple low-cost launches in a short timeframe. The vehicles will be fully 3D printed out of high temperature alloys that are relatively easy to procure as opposed to high temperature composites, which have low availability and are cost prohibitive. DART AE will be able to fly at a speed of Mach 7.

In April 2022, the Australian government has awarded Hypersonix a $8 million MMI Defence grant for the manufacture and launch of the 3D printed DART AE technology demonstrator. The grant gives Hypersonix the necessary funding to quickly progress its core scramjet technology that has been fully developed in Australia.