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Go UP young man!
On Sep 11 we got out to the silo to do a water injection static test. The idea was to inject water after the catalyst pack as inert mass that would take up space in the nozzle to increase thrust even though it would hurt ISP. It was an experiment, and we had the extra test nozzles from Luna City that we could drill a hole in to add the water injector.
It turns out that the thrust went down from about 550 pounds to 400 pounds. I think it took too much heat to boil the water. At least with 80% peroxide, injecting cold water does not increase thrust. If we had preheated the water like a steam rocket, or injected something like liquid CO2 where the vapor pressure starts out greater than the chamber pressure then it might have worked.
After that, we needed to switch back to the original nozzle and static test it to make sure there were no problems. We didn't get to that test on the 11th so on the 17th we went out, did that test, and prepped for a tether test, but didn't do it. Friday is the first day of fall so we're not going to make my goal of resuming tether testing this summer, but look for an update in October about our tether test.