I mentioned previously that last week we signed a contract that will allow me to get on-payroll at Altius. I’ve since talked with the customer and wanted to give a little update on what we’re doing. The contract is with the Advanced Programs group at United Launch Alliance, performing a quick feasibility study for one of the subsystems in their Integrated Vehicle Fluids system they’re developing for Centaur and Delta Cryogenic Second Stage. More info about IVF can be found on pages 8 and 9 of this ULA paper, but the gist of the development is that current missions are duration-limited by the RCS engine hydrazine source, the helium source for tank pressurization and purges, and battery power. ULA is developing the IVF module to see if they can eliminate the hydrazine and helium supply in a way that allows them to run a mission for as long as they have LOX and LH2 left over in their main propellant tanks. Here’s an illustration of an early version of the IVF, from the paper above:
While the actual goal of the IVF project is to provide longer duration missions for existing customers like NASA and the NRO, I personally think that it will also provide a good step towards the eventual use of propellant depots. By cutting down on the number of fluids needed to reuse the stage, and since the RCS fluids are fed off of the main propellant tanks, it makes it a lot easier to refill and reuse the stages eventually. You’ll still need the actual propellant transfer mechanism, but it will make things a lot simpler. Also, it will make construction of depots easier, because they need power and ACS as well. By bringing “refuelable” stages closer to reality, it makes the depot demand side more compelling.
We’re glad to have the chance to participate in a project like this for ULA, and look forward to working more formally with this group I’ve been involved with informally over the years. I don’t yet want to go into details on what our little contribution to this project is, but when I get permission to say more, I’ll definitely fill you all in on what we’re up to.