Video of GEM 63 Rocket Motor Test

Video Caption: Our GEM 63 rocket motor fired for approximately 105 seconds September 20 as we completed its first ground test at our Promontory, Utah, test site. The booster, developed for use on the United Launch Alliance Atlas V rocket, will be used as a direct replacement of the previous strap-on boosters beginning in July 2019.

  • Francesco Barato

    ULA CEO Tory Bruno stated that the reason for choosing the GEM-63 for the Atlas V and Vulcan is because it offers higher performance and almost half the cost of the AJ-60A boosters, currently being used on the Atlas V. Does someone know why?

  • duheagle

    I imagine it’s because the contract for the AJ-60A’s was signed during the ULA monopoly cost-plus era when economy wasn’t any kind of priority. Bruno signed the GEM-63 contract fairly recently, after SpaceX had upended the worldwide launch industry and it was plain that economy would be a key – probably the key – priority for the indefinite future.

  • Francesco Barato

    It seems to me that Aerojet is slowly giving up with the large motor business, either solids or the neverending AR-1…

  • Jeff Smith

    I think that’s the case – do you have a link or reference to where Tory has said that?

  • duheagle

    “Giving up” implies something voluntary. What’s happening is that AJR is having big pieces of its business involuntarily ripped away either by other suppliers or by obsolescence of the vehicles which employ said products. The end result is that what you say – AJR’s non-presence in the large motor business – may well come to pass over the next few years. AJ-60A and RS-68A are winding down. AR-1 may never find a customer. RS-25E’s future is as problematical as that of the SLS which it is to power. Absent recent decisions by Northrop Grumman and ULA to use the RL-10 for upper stages of new rockets (OmegA and Vulcan, respectively), AJR would soon have had no presence at all in major launch vehicles. As things stand, their days as a maker of booster engines will, in all probability, end in only a few more years.

  • Francesco Barato

    twitter

    twitter.com/torybruno/status/981336075544100865

  • Francesco Barato

    There is a bit of “voluntariness” in surrender. They could invest more money and try to compete… However they will probably loose the same, so “giving up” is maybe the best decision for a company that has other better business to focus on…