British nuclear fusion company Pulsar Fusion set fire to a chemical rocket engine that runs on a combination of nitrous oxide, high density polyethylene, and oxygen.
Acceptance testing of the UK-built rocket was conducted at COTEC, a UK Department of Defense site in Salisbury Plain, southern England.
We spoke to the company’s CEO, Richard Dinan, in 2018, when he discussed the prospects for fusion energy and the use of technology for space travel as well as power generation. In 2020, it was showing an ion thruster with plasma operating at several million degrees and particles fired at speeds of over 20 km per second.
Pulsar Fusion engine (click to enlarge). Photo: Pulsar Fusion
This month it’s the turn of chemical rockets, which are still needed to get from Earth to orbit (although SpinLaunch and its impressive accelerator are noteworthy, having performed a first vertical test of the launch system. rotating in October.)
“What I learned,” said Dinan The Reg, “is that everyone knows how rocket engines work. A lot of people are rocket engine experts. But none of those people can build rocket engines. The people who can build rocket engines are the ones who dismantled 20 engines which broke down … “
Following repeated changes, “the first test was positive! Dinan said, “It did not explode and the flames came out from the right end.”
We tested our first hybrid rocket motor earlier this week.
A very good result for our first tests using HDPE / N2O fuels. pic.twitter.com/vsnVPDfzEm
– Richard Dinan (@RichardDinan) 22 November 2021
From a thrust point of view, the relatively small engine was limited to five kN during testing, although Dinan told us the goal was to reach 100 kN as development progressed. For comparison, Rocket Lab’s Rutherford engine, nine of which power the first stage of its Electron booster, produces 24kN at sea level while SpaceX’s Falcon 9 Merlin engine will increase to 854kN.
Unlike powertrains from Rocket Lab and SpaceX, Pulsar’s hybrid engine runs on high-density polyethylene fuel and oxygen. An oxidizer is needed for the magic to work. The fuels themselves are described as non-toxic and the failure modes should be relatively mild if something goes wrong (compared to traditional liquid fuel engines.)
Pulsar has no plans to build a rocket himself, instead preferring to sell local technology as an alternative to American options (often crippled by export restrictions). The same goes for its Hall Effect Thruster (HET), for which UK government funding was received in September. Dinan told us the HET units had just passed a 20G vibration test at another UK facility and had a time slot set aside in 2023 for an in-orbit demonstration.
“I think we can do better than that,” he said of the vibration test.
Fusion power remains an ambition for Dinan’s future although the addition of hybrid rocket engine technology as well as ion thruster gives the company a few options and could spark industry interest.
“If we could say, ‘We have built and tested satellite engines, and they work and we have built and tested launch engines, and they work … Now we want to build a fusion engine …’, it makes us more credible. “
A first prototype of such an engine is currently expected for 2025. ®