If you have any questions or comments about DIRECT, ESAS, Constellation, Augustine or any of the other parts that led to SLS, please post them here and we'll try to answer/discuss the best ones!Ross.
PLEASE PLEASE PLEASE record this!!!! I'll be airborne and the company frowns on us watching videos in the cockpit.
Reusability. The Falcon 9 came online several years after Direct. What would Direct have done different if Falcon-9 reuse had been demonstrated earlier?Hindsight is 20-20 but given what you all know now, what should have been done different for Direct w.r.t to technology, people, anything?
Wonder if it was viable to replaced the RS-25 with J-2X after the initial batches of DIRECT launches? Possibility of relatively common engines for the core and the upper stage.
Quote from: Zed_Noir on 11/11/2023 12:23 pmWonder if it was viable to replaced the RS-25 with J-2X after the initial batches of DIRECT launches? Possibility of relatively common engines for the core and the upper stage.Unfortunately the J-2X can only operate in vacuum, so it could not have been used on the Core Stage.Just supposing a sea level variant were also developed ($$$ and many years) you would have needed roughly 2 times as many of them to match the thrust of the SSME's and you would also lose significant performance because the SSME's staged combustion system makes much more efficient use of the propellants compared to J-2X's gas generator cycle.The vac J-2X is already 18s Vac Isp lower than SSME and I'd guess you'd lose another 10-20s with a lower ratio sea-level capable nozzle variant. That's quite a lot to be giving away.Ross.
Whatever happened to C-Star Aerospace?
Quote from: kraisee on 11/10/2023 07:09 amIf you have any questions or comments about DIRECT, ESAS, Constellation, Augustine or any of the other parts that led to SLS, please post them here and we'll try to answer/discuss the best ones!Ross.Hi Ross,* Looking back 15 years since I came across DIRECT (and NSF), I wonder if in hindsight the Jupiter-130 + Orion + Cargo module concept would still be a money drain - if still better than handing crew capability to the Russians - for it to be unsustainable. That assumes that's all the USA have to support the ISS, plus what become the CRS program, for almost 1 whole decade until Crew Dragon eventually manages to work in 2020. Also do you think that large MPLM-like module carried on each flight would have killed half of the demands for the COTS-CRS program, making a switch to commercial programs more difficult?
* When we were still arguing about Ares and DIRECT was being proposed, no-one would have even imagined that the Jupiter-241H-DIVUS (cough) would eventually fly just 5 months before another SHLV - then floating around as a certain "Falcon XX" - that I bet all but one person on planet Earth (well, maybe more than 1 in that company) would have ever guessed to be really gonna flying.
Yet this was exactly what happened. I want to ask - what was going to be the "end game" of Jupiter when your plans were proposed? Were there considerations for your team to ask NASA to make a commercially bid SHLV program eventually (maybe say ~2019 as of your 2009 v3 plans) to assist with or replace Jupiter eventually for what was then Constellation? Do you think Jupiter would have ever been competitive with something like Starship had your v3 plans end up as reality?
* What would you think about modifications to your plans if someone from the future told you in 2009 that the small company that just flew a small rocket into orbit would end up with an Ares I-Orion like system that can fly 100 times/year AND designs and flies a real Shuttle successor & SHLV that promises to revolutionize transportation to and from orbit 15 years from then? Would you still push DIRECT as hard as it could, or would you support some other kind of stop gap and transition to commercial transportation contracts?
That was a long awaited, terrific stream. Glad to both be reminded of what happened, and see so much information that can only now be disclosed. In the past I've asked/been a pest about if there was ever going to be a written history of DIRECT, but the idea was kiboshed because so many participants were still involved in the industry and worried about repercussions. With the passage of time and this video, do you think things may have changed, and an enterprising journalist might be able to at least start archiving all this information/history to be brought together at some point in the future? Be a shame if (god forbid) a hard drive crashes or someone is lost, along with all their memories of how and what happened.
I think at one point you said you only had 30 people watching, that might have been 30 people logged into youtube. Many people (like myself) just lurked without logging in.
Quote from: JAFO on 11/11/2023 09:09 pmThat was a long awaited, terrific stream. Glad to both be reminded of what happened, and see so much information that can only now be disclosed. In the past I've asked/been a pest about if there was ever going to be a written history of DIRECT, but the idea was kiboshed because so many participants were still involved in the industry and worried about repercussions. With the passage of time and this video, do you think things may have changed, and an enterprising journalist might be able to at least start archiving all this information/history to be brought together at some point in the future? Be a shame if (god forbid) a hard drive crashes or someone is lost, along with all their memories of how and what happened.Yes, I've been approached about four times over the years. I never really felt comfortable with the idea of a book, because it felt like sticking the knife into the agency, and that's the absolute very last thing I ever wanted to do.But time has passed and Deb, my better half, who is an amateur writer and really first-class editor, has bent my ear about the idea of a book telling the story a couple of times in the run up to this interview with David and Lewis. I guess, that as long as such a thing could be done in a respectful manner, I'm not so against the idea any longer...
Quote from: JAFO on 11/11/2023 09:09 pmI think at one point you said you only had 30 people watching, that might have been 30 people logged into youtube. Many people (like myself) just lurked without logging in.Not sure how YT measures such things. I'll check with David for you, and see if he knows what the deal is.Ross.
