Inside the countdown to Australia’s first indigenous rocket launch

In 2018, Gilmour Space Technologies developed the world’s largest single-port hybrid rocket engine. Now the Queensland-based space company is preparing to launch Eris – the first Australian-made rocket – into orbit.

With most of the three-tier utility vehicles already manufactured and final testing and assembly underway, Gilmour Space founder and CEO Adam Gilmour sat down with him create to discuss qualification, satellite transport and the future of Australia’s space sector.

Testing makes perfect

Qualification for an orbital space rocket involves a series of intensive tests and rehearsals on the ground, including functional and environmental assessments of all major rocket systems, components and structures.

“When rockets go up, they shake a lot,” Gilmour said. “So one of the big things you do in environmental testing is put parts of the rocket on a shaker table and simulate the vibrations of the launch.”

A radio frequency anechoic chamber can test components such as antennas that use radio frequencies or are susceptible to radio frequency interference.

Thermal tests are also essential to simulate the effects of “cooking” and “cooling” in space depending on the position of the sun and to test the heat transfer of the rocket motor.

“You can also put the rocket components in a vacuum chamber to simulate the vacuum of space,” Gilmour said.

Assembling the rocket is another mammoth task for the team, with more than 3,000 components making up the launch vehicle, and is expected to take up to 3-4 months.

When final assembly is complete, the Eris will be taken to the launch site in Bowen, North Queensland, for further system-integrated functional testing, including engine testing and other electronic evaluations.

“We’re doing a full ‘wet dress’ rehearsal, [where] We fill it up with all the fluids and make sure the valves, for example, are working as expected,” Gilmour said.

“We’re building a second vehicle pretty close behind the first one because we want the ability to recycle it fairly quickly.

“Should there be a bug or an anomaly, we will conduct an investigation to see what went wrong, fix it and then try again.”

Innovative engine technology

While the Eris first and second stages are powered by Gilmour Space’s lower-cost hybrid rocket engine, the company’s newly developed liquid rocket engine will be used, will engage in third gear.

Testing the Phoenix engine in May 2022

Designed and manufactured in Australia using 3D printing, Phoenix has been fully qualified for deployment as of October 13th.

“It has a regeneratively cooled engine, which means the fuel goes through small tubes on the outside and then back and up into the engine [combustion] chamber to keep the rocket motor cool,” Gilmour said.

This innovative method allows the propellant to boil before it reaches the chamber, meaning the rocket can run longer.

The relative fuel efficiency of a liquid rocket engine also delivers significantly more payload to orbit.

“[Specific impulse] is very important in rockets because the more efficient you are, the less fuel you need to generate a certain amount of thrust,” says Gilmour.

What’s next for Eris?

The first Eris rocket was designed as a technology demonstrator for launching small satellites weighing around 100 kg into lower Earth orbits (LEO).

However, much of Gilmour Space’s technology is expected to be carried over into its larger vehicles, with work already beginning on a new rocket – Eris Block 2. Better tailored to customer needs, this vehicle could be Gilmour Space’s bread and butter.

“Block 2 can hold 1,000 kilograms, so you can [bring] many satellites operating at the same time,” Gilmour said. “We’re also working on a booster stage for Eris Block 2 so you can launch payloads to the moon.”