Hot Fire

As we emerge from finals weeks, we want to update you on a major test. On April 7th, 2018, we carried out our first "hot fire" test of our rocket engine. It's a kinetic and exciting test to watch, and a major milestone in a rocket engine development campaign.
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When developing a new rocket engine, it’s usually a multi-month process which starts with designing the engine, is followed by building it, and finally has you enter an escalating series of tests until you can be confident enough to fly it. The usual test sequence is water flow, (cryogenic) cold flow, your first hot fire, your first full duration hot fire, and then optimization to taste. While a rocket engine seems simple enough from a distance, there are hundreds of details that must be just so. Many of those critical details are in the plumbing that brings the fuel and oxidizer to the right place, at the right time, in the right amounts. And the demands on that plumbing are severe: timing requirements are tight, the flow must be smooth,  measured, and consistently delivered in order for the engine to work correctly. Mess up any of those details, and your best case scenario is nothing happening.

For this test, we drove up to Maine, home of bluShift Aerospace. BluShift is one of FAR OUT's sponsors, and they have been superb hosts; in between their own rocket tests, they've allowed us to hop in and use their testing facilities. Working with them has been a distinct pleasure.

Around midday, we were joined by representatives from ENGIE, our second sponsor involved in this test. Our engine is designed to burn liquid oxygen and liquid methane, nicknamed MethaLox. ENGIE is a liquid natural gas distributor, and for our purposes natural gas was a good proxy for pure methane. ​

ENGIE's support was extraordinary. They not only donated the LNG for the test, brought it to our remote testing site, and trained our operators in its safe handling, but they purchased the dewar for this outing. Other rocket teams in the competition failed to make the hurdle of securing LNG fuel for the engine development for FAR-MARS, and we are tremendously grateful for their generous donation.
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After two days of preparing the site, the test stand, and the engine itself, we were finally ready. We reviewed our procedures one last time, fueled up with our cryogenic natural gas and oxygen, and prepared to fire the engine. From the safety of our bunker, we attempted to fire twice.

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Our post-test engineering review concluded that the likely culprit was a weak ignition source. Although ignition was initiated, it hard started and blew itself out, blasting the ignitor out of the engine in the process.
Unfortunately, that left us with too little time left to fly in the 2018 FAR-Mars competition. We are planning to continue development, with the target of flying next year in the 2019 FAR-Mars competition.