It has been a while now since we heard anything about the awesome Jupiter family of hlv's. SLS got in the way.If and when SLS fails and is quietly pushed aside, is it possible that there will be a resurgence of the Direct architecture ?kraisee ??clongton ??
Quote from: MickQ on 01/31/2022 03:43 amIt has been a while now since we heard anything about the awesome Jupiter family of hlv's. SLS got in the way.If and when SLS fails and is quietly pushed aside, is it possible that there will be a resurgence of the Direct architecture ?kraisee ??clongton ??DIRECT was based on re-using existing shuttle hardware and existing shuttle infrastructure (including manufacturing infrastructure) to the maximum possible extent.Unfortunately most of the shuttle infrastructure and all of the STS manufacturing infrastructure was demolished to make way for the Space Launch System.So, the basis on which DIRECT could have been a technical success no longer exists. Which is why the DIRECT architecture can't be resurrected.
One of the side mount versions would have been much quicker to develop. No change on the solids or tank. A pod for liquid engine retrieval. It would have allowed about 70+ tons to LEO. Shuttle could still have carried the astronauts or Orion could have been mounted on the side pod as shown. A lot of in space assembly could have been done. Also, liquid boosters could have been built to replace the solids eventually with all the money saved. Flyback boosters were what was suggested back then. Now land back boosters would save mass. Like everyone said, Direct is dead. Solids are a dead end. They are good for thrust on first stages or ICBM's. Parachuting them back into the ocean, retrieving them, and refurbishing them costs as much as new ones. Land back liquids, as SpaceX has shown cuts operating costs a lot more.
Quote from: spacenut on 01/31/2022 02:19 pmOne of the side mount versions would have been much quicker to develop. No change on the solids or tank. A pod for liquid engine retrieval. It would have allowed about 70+ tons to LEO. Shuttle could still have carried the astronauts or Orion could have been mounted on the side pod as shown. A lot of in space assembly could have been done. Also, liquid boosters could have been built to replace the solids eventually with all the money saved. Flyback boosters were what was suggested back then. Now land back boosters would save mass. Like everyone said, Direct is dead. Solids are a dead end. They are good for thrust on first stages or ICBM's. Parachuting them back into the ocean, retrieving them, and refurbishing them costs as much as new ones. Land back liquids, as SpaceX has shown cuts operating costs a lot more. Congress required the SLS launch vehicle family to be able to evolve to launch 130 metric tons to orbit. The Side Mount concept could not evolve to the 130 metric tons requirement.
Side mount for payloads is crap
Wood170 is correct. Which is why I think they should have built this system:
Quote from: MATTBLAK on 01/31/2022 09:16 amWood170 is correct. Which is why I think they should have built this system:Unfortunately that configuration was an even bigger kludge than shuttle was.
Quote from: woods170 on 01/31/2022 04:59 pmQuote from: MATTBLAK on 01/31/2022 09:16 amWood170 is correct. Which is why I think they should have built this system:Unfortunately that configuration was an even bigger kludge than shuttle was.I don't agree, but Atlas V Phase 2 would have been my preference, along with upgraded Delta IV-Heavies.
Quote from: woods170 on 01/31/2022 04:59 pmUnfortunately that configuration was an even bigger kludge than shuttle was.I don't agree, but Atlas V Phase 2 would have been my preference, along with upgraded Delta IV-Heavies.
Unfortunately that configuration was an even bigger kludge than shuttle was.
I see with some sadness that Griffin's tenure is seen very negatively today. What was THAT wrong? It was only a question of insufficient money, or something else? Why SLS is constrained for a single flight per year? It is only because of the costs, or something more substantial? Wasn't the Augustine committee just right that either invest more money to human BLEO, or wait for something new?
I see with some sadness that Griffin's tenure is seen very negatively today. What was THAT wrong? It was only a question of insufficient money, or something else? Why SLS is constrained for a single flight per year? It is only because of the costs, or something more substantial?
Griffin is portrayed as obstinate and ego-driven, and is blamed for dictating the troubled Ares I design sans trade studies or technical evaluations. I’m honestly curious whether this apocryphal tale is real or myth. Anyone?
Direct would have ended up the same way SLS has. Way over budget, way over schedule etc. The same lack of a Mission, the same contractors involved, the same financial and political forces at work. The engineering details wouldn't really have changed the long term outcome.
Ares I was a disaster. He opposed using EELVs for no reason, and that put the program back a whole decade probably.
"3 And why beholdest thou, Michael Griffin, the mote that is in thy EELV's eye, but considerest not the beam that is in thine own Ares 1 eye?4 Or how wilt thou, Michael Griffin, say to thy EELV brother, Let me pull out the mote out of thine EELV eye; and, behold, a beam is in thine Ares 1 own eye? 5 Thou Michael Griffin hypocrite, first cast out the beam out of thine own Ares 1 eye; and then shalt thou see clearly to cast out the mote out of thy brother's EELV eye. "
Wasn't the Augustine committee just right that either invest more money to human BLEO, or wait for something new?
Everything about Constellation was a disaster starting with Ares I. Griffin was in denial about the severe thrust oscillation problem on Ares I. They were designing a friggin multi-ton shock absorber to be placed between the first and second stage to keep the shaking from kicking the crud out of the crew flying on the rocket. The rocket was already severely weight constrained due to using a shuttle solid booster as a first stage. In July of 2008, Griffin came to speak at the EAA AirVenture in Oshkosh. I asked him about this issue and was dumbfounded by the response. He said if this was the worst problem they needed to tackle that the development of Constellation was going to be a breeze. The video of his response might still be up on YouTube. I haven't looked in a while.
But the future we got, where NASA spins its wheels for a decade longer and almost everything seems to end up using SpaceX launchers, is not so bad overall.
I for one would take SLS over another 10 years without Heavy Lift... Respectfully.
Quote from: geza on 02/01/2022 09:58 amWasn't the Augustine committee just right that either invest more money to human BLEO, or wait for something new?That's how Augustine was widely interpreted, but if you read the report closely, you see that there was another way. In Section 6.5.3, on p. 93 (PDF p. 94), the report states that the use of EELV-derived rather than Shuttle-derived super-heavy-lift launch vehicles "may ultimately allow NASA to escape its conundrum of not having sufficient resources to both operate existing systems and build a new one."Congress and many others eagerly interpreted "super-heavy lift" to mean Saturn V-class or larger, but, again, a close reading of the report shows otherwise. Augustine defined "super-heavy lift" as anything more capable than existing EELVs, i.e. more than 25 metric tons to LEO (Delta IV Heavy) and concluded that a capability of about 50 metric tons is adequate (Sect. 5.2.1, p. 64ff).
Quote from: randomly on 01/31/2022 07:08 amDirect would have ended up the same way SLS has. Way over budget, way over schedule etc. The same lack of a Mission, the same contractors involved, the same financial and political forces at work. The engineering details wouldn't really have changed the long term outcome.This is not a knock against DIRECT, but to first order, I agree with this viewpoint. The engineering details are really secondary to the cost centers and management practices that any space transportation system built on the Shuttle (and arguably Apollo) workforce and infrastructure will inherit. That has to be broken up in order to move to something more (not less) effective and efficient. That doesn’t mean firing that workforce or demolishing that infrastructure. But if we’re serious about human space exploration, it does mean we need them doing more important things than competing very poorly with industry on launch vehicles and capsules.FWIW...
I won't name names, but someone who worked in Griffin's office at the time, told me Griffin actually ended up hating the Ares-I, but his overlords gave him his marching orders to do what ATK wanted.That's because separately, NASA was told point-blank by ATK that they were going to pull completely out of producing SRB's for NASA unless they could have a big fat, lucrative development contract.
I won't name names, but someone who worked in Griffin's office at the time, told me Griffin actually ended up hating the Ares-I,
but his overlords gave him his marching orders to do what ATK wanted. That's because separately, NASA was told point-blank by ATK that they were going to pull completely out of producing SRB's for NASA unless they could have a big fat, lucrative development contract
The ATK pressure was a fairly big problem NASA management had to juggle, but the political pressure from Shelby was the brontosaurus in the room. He had - and still has - the final power to write the checks that NASA uses to pay for each and every project and program. And a lot of other government activities besides. He gets what he wants. Period.
I probably missed it, but wouldn't needing to spend $100 million each plus development for expendable 25s have made all of the alternatives a little pricey?
Quote from: kraisee on 02/02/2022 04:14 amI won't name names, but someone who worked in Griffin's office at the time, told me Griffin actually ended up hating the Ares-I, but his overlords gave him his marching orders to do what ATK wanted.That's because separately, NASA was told point-blank by ATK that they were going to pull completely out of producing SRB's for NASA unless they could have a big fat, lucrative development contract.Political blackmail. Why am I not surprised? Oh yeah, now I remember... Something similar got us SLS: "That's right Lori. You can have Commercial Crew as long as I can have SLS"(Bill Nelson speaking to Lori Garver and Charlie Bolden in 2010)
Quote from: woods170 on 02/02/2022 10:20 amQuote from: kraisee on 02/02/2022 04:14 amI won't name names, but someone who worked in Griffin's office at the time, told me Griffin actually ended up hating the Ares-I, but his overlords gave him his marching orders to do what ATK wanted.That's because separately, NASA was told point-blank by ATK that they were going to pull completely out of producing SRB's for NASA unless they could have a big fat, lucrative development contract.Political blackmail. Why am I not surprised? Oh yeah, now I remember... Something similar got us SLS: "That's right Lori. You can have Commercial Crew as long as I can have SLS"(Bill Nelson speaking to Lori Garver and Charlie Bolden in 2010)So I am not a fan of the SLS & its use of SRB's, but what really were the alternatives for heavy lift back in the 2009 time frame? The US did not pursue kerolox propulsion like the RD-180, and basically committed themselves to hydrolox in either 1.5 stage configuration like STS, or Delta Heavy single stick & tri-core configuration. I would think that back in that time SRB's were the only realistic option for heavy lift. Would it have been politically viable to use clusters or RD-180 for a single stick first stage even back then? The only options I recall that were floated was a resurrection of the F-1 as an updated engine from Dynetics & the Pyrios proposal for making LRB's. How long & at what risk was that path?I think it may be a stretch to accuse ATK of blackmail for telling NASA they would shut down making SRB's for them if they did not get a contract. That is a supplier giving a customer a straight up honest business assessment of what they would do without a contract for the SLS. What is ATK supposed to do? Keep open facilities & manpower assignments to a product line with no other customers? The military doesn't need the STS or SLS SRB's so there is no point to ATK wasting any money on them if NASA didn't select them. The real question is why did NASA yield and judge SRB's as the technology path to commit to for SLS vs. developing alternatives for stage 1 main propulsion? It think those answers have all been re-hashed many times & are explainable by politics & pork. It doesn't need to cast shade on ATK explaining a business reality that any normal company would react to the same way.
A key to this vision is the requirement to complete assembly of the ISS and to retire the Shuttle Orbiter, without in the process incurring another lengthy hiatus in the ability of the United States to conduct crewed spaceflight operations. To this end, we recommend phased development of the new CEV, with the “Block 1” version designed for LEO access and return only, with a later “Block 2” version suited to the requirements of interplanetary missions. The CEV would be launched on a new human-rated vehicle, possibly based on the existing Shuttle solid rocket motor (SRM), augmented with a new liquid upper stage. Such a system could be available before 2010.
I have a suggestion for the Nasaspaceflight.com brass: Gather the best of all these endless pro, and mostly-con arguments over the last 10+ years, and then publish a book called "SLS Facts and Fiction", or something like that! Or maybe...?You could even get Mr.Griffin and Coastal Ron to write 2 forwards, Sell it to raise L2 scholarship money, or to provide beer at future launch parties.Then ban this topic forever!
Perhaps even more damaging than the enormous costs is the schedule paralysis that goes along with these cost plus contracts. There is no real schedule pressure. All the financial incentive for contractors is to slow walk everything and maintain there funding for as long as possible.
I think they should’ve “just” made more regular SSMEs.Are they saving any additional money given all the extra development and qualification?How many regular engines would they need to make before it was more expensive than the expendable ones?
Quote from: Robotbeat on 02/02/2022 05:20 pmI think they should’ve “just” made more regular SSMEs.Are they saving any additional money given all the extra development and qualification?How many regular engines would they need to make before it was more expensive than the expendable ones?As I understand it, SLS does not use "regular SSMEs". It uses the 15 remaining SSMEs left over from the Shuttle program, but they were upgraded and modified because the SLS is physically different than the shuttle. The fact that the engines are inline with he tank was given as a big reason the modifications were required. This would have been true for most DIRECT proposals, I think. for SLS, making additional RD-25Ds would be more expensive. The last RS-25D was manufactured in 1998(?), so restarting the line would have been an adventure, and some things would need to be changed in any event to incorporate the adaptations.
Quote from: randomly on 02/02/2022 06:23 pmPerhaps even more damaging than the enormous costs is the schedule paralysis that goes along with these cost plus contracts. There is no real schedule pressure. All the financial incentive for contractors is to slow walk everything and maintain there funding for as long as possible.Cost Plus contracts have been around a long time. Many of the issues that prolong the project are from customer changes to specifications and/or the stretch out of programs by Congress.
So I am not a fan of the SLS & its use of SRB's, but what really were the alternatives for heavy lift back in the 2009 time frame?
Orion and its LAS had to be redesigned because of the insanity of Ares I, and it pushed everything back considerably.