Wanted to provide a quick update to on what we’ve been up to here at GO recently. We’ve been hard at work wrapping up our Phase I SBIR effort with AFRL on GOLauncher 1 as a hypersonic flight test platform. Support for the system throughout both government and industry has been really strong, owing to the versatility of the GO1 to fly a wide range of missions from deploying free flying experiments like X-51 or HIFiRE 6 to carrying a scramjet flowpath through mode transition, cruise, and accelerating flight. Turns out liquid rocket engines make for a kick ass hypersonic air vehicle when you want to cruise at Mach 6 for an appreciable amount of time. With any luck, we’ll be starting prototype hardware builds of the a systems integration testbed for the GO1 later this year.
In preparation for that prototype, we’re close to completing assembly, integration, and testing of a similar systems engineering testbed for a much smaller system – the GO Transfer Stage. In order to improve the payload performance of GOLauncher 2, we’ve developed a concept for a bare-bones, low cost stage to circularize the vehicle’s orbit with a couple hundred feet per second of delta-V after the upper stage burn and a long coast period. This provides 10-15% payload increase to the system, especially for higher altitude orbits, while also reducing requirements for the upper stage and limiting our orbital debris footprint. The design involves gaseous oxygen, gaseous methane, ablatively-cooled rocket engine, COTS propellant tanks and feed system, and basic avionics. It wasn’t intuitive that a gaseous system would win out in the trade space, but with the high Isp you get with GOX/CH4, this configuration even beats out hydrazine at this scale.
Anyway, enough with the systems engineering, back to the hardware. As I mentioned, we’re currently building the engineering development unit for the GOTS in our shop. Our goal here is not only to validate that we can get the system performance we’ve predicted, but also to build out a hardware and software integration framework that allows us to develop and debug incrementally as we iterate on the design, rather than only going through computational design and analysis cycles. The structure has come together nicely, utilizing the high pressure propellant tanks to take the main loads. We’re building out the engine (water-cooled design for ground testing) and avionics (evolved from GO-FET data acquisition system) components in-house this week in preparation for integration and testing over the next couple weeks.
We’ve learned a lot from going through a rapid design, analysis, build, integrate, and test cycle on the GOTS that we’ll be able to apply to both GOLauncher 1 and GOLauncher 2 here in the near future.