Lowering the Barrier to Entry into Amateur Liquid Rocket Engines
Joined July 2021
- Tweets 706
- Following 27
- Followers 3,132
- Likes 323
457 Photos and videos
We've published a reliable fix for Mojave Sphinx's most well-known fuel leak, the blue sealing washers on the forward bulkhead. You can find the retrofit instructions (as well as CAD of the modified part) located in the same release folder with the rest of the files.
8
323
Hands-on experience building rockets is extremely valuable for students going into the industry. This kind of support helps them dream and achieve ambitious goals!
May 14
We just partnered with the Musk Foundation to give out $175k in grants to advance the frontier of collegiate rocketry.
This is in addition to the $390k we’re already giving out to collegiate teams building propulsive self-landing rockets.
When we first started, people laughed and told us what we were attempting would be impossible.
2 years later, several student teams have achieved both TVC and throttled hotfire with liquid engines, and they are making fast progress on their hoppers. We’re already seeing hover attempts at a collegiate level!
These kids are doing this on 0.001% of a typical rocket budget, dedicating 80 hour weeks without any pay to build some of the most capable rockets outside of industry.
The reason why so many people fall in love with space and rocketry is because it is proof that humanity is capable of the impossible.
We want to continue to advance that mission.
Back to work.
1
21
982
this
May 2
more liquid rockets
1
2
14
826
Made a new pintle insert for our MSCX chamber today. These slotted pintles have given a substantial improvement over our usual scrintle injectors' mediocre efficiency, while still being quite simple to produce.
1
74
2,624
100 years ago today, Robert Goddard made the very first launch of a liquid bipropellant rocket.
5
37
1,144
If you've built a Mojave Sphinx, please let us know through our form! We use serial numbers to keep track of how many are out there - it's a critical metric to demonstrating the accessibility of amateur liquid rockets.
forms.gle/BfUCZJpBVnmKtmYRA
1
13
685
Serial numbers are assigned in the order that form submissions were received, so don't hold off if you've got one built. The liquid motor is the important part, so it's fine if you only made the propulsion system. (screenshots of CAD unfortunately don't count 🙂)
5
353
Sphinx SN 23 Kitty Hawk (not ours) is out here too, going for it's first launch!
35
810
8,640' apogee, burn was cut short because the pintle tip evidently burst and dumped out the remaining oxidizer
1
4
79
2,731
Back out at FAR on a calm Sunday morning, going for a launch of SN 12 Shiro Sphinx on our experimental pintle injector with ablative thrust chamber - hoping to set a new Mojave Sphinx altitude record.
1
37
773
Two good tests on Bobtail so far today, and currently recycling for a third. The new ox-centered pintle injector is working relatively well
29
978
Last month, @TurbulentSphere gave an excellent talk about the basics of amateur liquid rocketry. Give it a watch here:
youtu.be/Fi6vmynh4rM?feature…
1
4
29
2,706
This Saturday, we conducted three more tests of Bobtail, our in-development all-COTS liquid rocket. We found problems and solved problems, evolving the design toward better usability and performance.
1
24
650
15 Dec 2025
It's Half Cat Day, marking five years since we conducted our first test of a liquid rocket motor! Here's the longer message we posted to our discord server - so much has happened since then, and we couldn't have done it without the excitement and interest from everyone out there.
2
35
1,009
30 Nov 2025
Four tests completed us today, concluding with a Garfield Gorange E85 firing by Shiro Sphinx! That puts us at 100 firings, 12/15/2020 to 11/29/2025.
21
672
29 Nov 2025
A few weeks ago we did three Mojave Sphinx launches, which put us at 96 total liquid rocket firings since our first test. Tomorrow we'll round that out to 100 in under five years, including the debut of our newest design, Bobtail (pictured on the test stand)
2
20
573
19 Oct 2025
Composite photo of all three Mojave Sphinx launches taking off yesterday. Colorado School of Mines, UCSB Gaucho Rocket Project, and our own.
2
50
1,106