STS Shuttle discussion thread

[PB666]

That has got to be one of the . . . . . only wish they had showed the docking monitor in better detail

[sevenperforce]

10 hours ago, GoSlash27 said:

Well, yeah... but that's why it was supposed to have jet engines originally.

Chutes are, of course, the ideal failsafe. But if I cannot have a chute, I would rather rely on multiple redundant landing thrusters (assuming multi-engine-out capability) than an unpowered glide-landing at Mach 0.3.

Edited January 15, 2018 by sevenperforce

[GoSlash27]

Found a screen- cap. The original Rockwell concept was actually HOTOL.

Best,
-Slashy

[CatastrophicFailure]

Sigh. Well I'm all out of likes yet again, so here's Steve Buscemi riding a nuclear weapon: 

[PB666]

2 minutes ago, Starman4308 said:

I would rather have the US go for another couple decades without indigenous human spaceflight capability than risk astronauts in the disaster (and expensive disaster) that was the Space Shuttle.

That say alot right there. I don't see the shuttle as particularly dangerous, it was expensive, but then again so are the current gov't sponsored launch system. You saw the budget, where are all the post shuttle savings, in the last 10 years of shuttle operation the budget was at its lowest cost since 1961. It basically built the ISS (at least the habitable portion) .  I would feel safer in the shuttle than in a cessna in bad weather. The shuttle had two incidences, the first incidence can almost intirely attributed to the DoDs push for its PL delivery, which forced a launch on a morning that was too cold. The second was a risk they had known about but failed to deal with, but alas we forget 140 missions with 6 to 7 astronauts onboard. That is alot of people.

I don't mind that the soviets were delivering people to the ISS, but if you have an evolving space program, the manned space program should be more than that, and it should never be in a state where you are dependent on a potential competitor.

[PakledHostage]

1 hour ago, GoSlash27 said:

 Well, the Shuttle's thrust was in line with the Falcon Heavy. It's payload , OTOH, is not.

Its thrust was significantly greater than Falcon Heavy's and comparing the two launcher's payloads directly is pointless. Sure Shuttle could "only" deliver ~16 tonnes to the ISS, but the Shuttle stack as a whole could place on the order of 90-100 tonnes into orbit, including the orbiter itself.

You may scoff at the idea of including the orbiter in that number, but recall that the orbiter wasn't just dead weight. It was a self contained space station, laboratory, construction platform, satellite retrieval system, etc that was also capable of returning to a runway whole and with up to 14 tonnes of payload. And that portion of the orbital "payload" that returned didn't need to splash down into the ocean or plunk down onto the steppes of Kazakhstan and then be thrown away after each use.

 

[GoSlash27]

9 minutes ago, sevenperforce said:

Chutes are, of course, the ideal failsafe. But if I cannot have a chute, I would rather rely on multiple redundant landing thrusters (assuming multi-engine-out capability) than an unpowered glide-landing at Mach 0.2.

sevenperforce,
 Things have evolved since back when the shuttle was on the drawing board. Back then, the best way to get a vehicle where you wanted it was with a pilot and wings. Times have changed.

Best,
-Slashy

[PB666]

3 minutes ago, PakledHostage said:

Its thrust was significantly greater than Falcon Heavy's and comparing the two launcher's payloads directly is pointless. Sure Shuttle could "only" deliver ~16 tonnes to the ISS, but the Shuttle stack as a whole could place on the order of 90-100 tonnes into orbit, including the orbiter itself.

You may scoff at the idea of including the orbiter in that number, but recall that the orbiter wasn't just dead weight. It was a self contained space station, laboratory, construction platform, satellite retrieval system, etc that was also capable of returning to a runway whole and with up to 14 tonnes of payload. And that portion of the orbital "payload" that returned didn't need to splash down into the ocean or plunk down onto the steppes of Kazakhstan and then be thrown away after each use.

 

The bulk of the shuttles thrust was provided by LH2LOX and three very efficient engines, so it was relatively more efficient than FH would be, someday, maybe, if it can standup strait for more than a few hours.

I think the positing of scientific and in-space operation capabilities, unfortunately, goes on largely deaf ears here.

[GoSlash27]

1 minute ago, PakledHostage said:

You may scoff at the idea of including the orbiter in that number, but recall that the orbiter wasn't just dead weight.

 PakledHostage,
 Sorry, but the *entire problem* was that the orbiter itself was dead weight on most missions. A lot of the time, all we needed to take up was crew. We could do that with the shuttle, but we'd send along an entire airliner in the process. Most other times, all we needed to send was cargo. We had several other vehicles that were better at that job (and the Falcon Heavy is *clearly* superior... if it works). 
 In some instances, we did need to do both or actually use the unique capabilities of the Shuttle. Spacelab, Hubble, the ISS, etc. And thank goodness we had the shuttle to deliver it for us when we needed it. But really... in most cases it was just a liability.

Best,
-Slashy

[Starman4308]

8 minutes ago, PB666 said:

That say alot right there. I don't see the shuttle as particularly dangerous, it was expensive, but then again so are the current gov't sponsored launch system. You saw the budget, where are all the post shuttle savings, in the last 10 years of shuttle operation the budget was at its lowest cost since 1961. It basically built the ISS (at least the habitable portion) .  I would feel safer in the shuttle than in a cessna in bad weather. The shuttle had two incidences, the first incidence can almost intirely attributed to the DoDs push for its PL delivery, which forced a launch on a morning that was too cold. The second was a risk they had known about but failed to deal with, but alas we forget 140 missions with 6 to 7 astronauts onboard. That is alot of people.

I don't mind that the soviets were delivering people to the ISS, but if you have an evolving space program, the manned space program should be more than that, and it should never be in a state where you are dependent on a potential competitor.

Your opinion on the Space Shuttle's safety does not outweigh operational experience of 2 LOCV in 135 missions. While the individual flaws have been patched, you still had several fundamental safety issues that not only provided ripe fruit for more malfunctions, but also made it very difficult to survive significant malfunctions.

More conventional capsules have the advantage of a very simple and robust abort mode that applies throughout launch: shut down the booster, separate from the stack and fire the LAS, and align for reentry. The Shuttle literally couldn't even start an RTLS abort until after the SRBs had burnt out, and emergency reentry was a very finicky business to avoid overstressing the Shuttle's frame.

More conventional capsules have the advantage of being on top of the stack: debris from the rest of the booster can't fall onto it, and it's relatively easy to separate from it.

Much of the low operational cost in the last years of Shuttle operations was due to winding down of the program, in particular the shuttle improvement budget. Thorough budgetary analyses continue to suggest that the current, commercial approach to spaceflight is several times cheaper than operating the Shuttle would be.

 

20 minutes ago, PakledHostage said:

You may scoff at the idea of including the orbiter in that number, but recall that the orbiter wasn't just dead weight. It was a self contained space station, laboratory, construction platform, satellite retrieval system, etc that was also capable of returning to a runway whole and with up to 14 tonnes of payload. And that portion of the orbital "payload" that returned didn't need to splash down into the ocean or plunk down onto the steppes of Kazakhstan and then be thrown away after each use.

That's because I do scoff at including the orbiter in that number. All that space station, laboratory, construction platform equipment, was limited by the size of the fuel cells used to power the Shuttle. In terms of equipment that went up to space and stayed up there, the Shuttle's payload capacity was miserable. For the rare cases where the Shuttle's unique capabilities were extensively used, quite frankly, we probably could've done it cheaper with a single-use mission module sent up separately on a medium/heavy-lift vehicle, to which a small crew transfer vehicle would dock for the duration of the mission.

[PB666]

1 hour ago, Starman4308 said:

Your opinion on the Space Shuttle's safety does not outweigh operational experience of 2 LOCV in 135 missions. While the individual flaws have been patched, you still had several fundamental safety issues that not only provided ripe fruit for more malfunctions, but also made it very difficult to survive significant malfunctions.

More conventional capsules have the advantage of a very simple and robust abort mode that applies throughout launch: shut down the booster, separate from the stack and fire the LAS, and align for reentry. The Shuttle literally couldn't even start an RTLS abort until after the SRBs had burnt out, and emergency reentry was a very finicky business to avoid overstressing the Shuttle's frame.

More conventional capsules have the advantage of being on top of the stack: debris from the rest of the booster can't fall onto it, and it's relatively easy to separate from it.

Much of the low operational cost in the last years of Shuttle operations was due to winding down of the program, in particular the shuttle improvement budget. Thorough budgetary analyses continue to suggest that the current, commercial approach to spaceflight is several times cheaper than operating the Shuttle would be.

That's because I do scoff at including the orbiter in that number. All that space station, laboratory, construction platform equipment, was limited by the size of the fuel cells used to power the Shuttle. In terms of equipment that went up to space and stayed up there, the Shuttle's payload capacity was miserable. For the rare cases where the Shuttle's unique capabilities were extensively used, quite frankly, we probably could've done it cheaper with a single-use mission module sent up separately on a medium/heavy-lift vehicle, to which a small crew transfer vehicle would dock for the duration of the mission.

First off you are fabricating a problem that the shuttles track record suggest really does not exist, Soyuz had two loss of crew events, the shuttle had two loss of crew events, both used markedly different systems. You know, space is not for the feeble at heart, neither is cutting edge science by the way. I spent many an afternoon with a geiger counter sitting next to me pinned to the right; and on another day I might be diluting the highest concentration of the most poisonous stuff known to man. If you want an argument solely about minimizing risk to zero, you have already lost I don't listen to you and I don't care. The functionality was and is always more important. Certainly absolute risk minimization not an argument the DoD uses. The problem you are creating is a artificially problem. Although it put 140 flights into space, and brought home all but one. It was a flying brick, but being a flying brick did not bring the one return failure, it was the sort of careless attitude about tile damage. This is something that occurs at 50km. Soyuz also had a problem at high altitude, the sprung a leak in their capsule, everyone died. That's space, you get the glory, you take the risk. Who are you taking the risk for, hopefully science, sometimes for the DoD, and sometimes other stuff. I have to add to this that at least the shuttle had a runway suitable to its needs, that's a luxury that the concorde did not have and yet it was allowed to fly for 20+ years before that was realized.

If you think the space shuttle is a risky afair, then by the logic humans have NO business going back to the moon or mars, or trying to start a colony. All of these things are a magnitude more risky than the shuttle. Essentially that argument crops NASA to LEO ISS runs,  completely unacceptable restriction.

Let me make my position clear, its not about the shuttle, I don't care if it looked pretty at launched or was unsafe on occasion or whatever . . . . we lost functionality that should not have been allowed to lapse.
THe argument has been made that other systems could/can do what the shuttle can . . . . Ok where are they, I see alot of expensive systems that can't do a third of what the shuttle did and still we are two years from a manned US based launch system . . . that is if you trust the contractors. . .all of whom are notorious for delays. The shuttle function replacements have been all but a complete failure. No in space repair, no manned capability, no satellite return capability, no capacity to assemble space stations . . . . . . Thats what it is, NASA intended replacement of the shuttle has not worked except for the rather blind luck of having SpaceX step up and want to start batting for them. And it looks like SpaceX will be sending crews to the ISS before the Orion contractors are ready to launch there trial run of the complete module. At the rate they are building these things we would be lucky to see a complete deep space module one per 3 years. Unacceptable.

 

Edited January 15, 2018 by PB666

[tater]

The early shuttle designs were pretty interesting, as were some competing ideas for SSTO and Semi-SSTO designs (drop tanks) that would have propulsively landed.

The risk of Shuttle was obviously high in retrospect, but I think the principal loss was as an opportunity cost. Shuttle sucked up so much budget that there was no possibility to really push any alternate designs that might have done a better job.

[CatastrophicFailure]

50 minutes ago, PB666 said:

Soyuz had two loss of crew events, the shuttle had two loss of crew events, both used markedly different systems.

Soyuz had two LOCV events... during development (Challenger and Columbia were both “operational” flights), and the Soviets learned from the mistakes and rectified the flaws. Soyuz also demonstrated the critical importance of launch abort capability, with two crews saved (one on the pad and one at high altitude, IIRC the latter outside the shuttle’s survivable abort window).

There’s calculated risk and unreasonable risk. Zero abort capability in the first two-ish minutes of flight and dicey prospects after till you’re nearly in orbit anyway, that is unreasonable. 

[tater]

@PB666, regarding Shuttle capabilities, I think that while you are right that Orion and Commercial Crew lack these capabilities, many are more valuable in theory than reality. Regarding delays, shuttle was delayed as well, then it blew up, and was delayed some more.

Also, to be fair to commercial crew, they are required to meet a safety standard grossly better than Shuttle itself actually demonstrated. If Commercial crew were to fly their first flights at the same risk level as STS-1, SpaceX could have thrown seats in the extant Dragon years ago I bet (the trunk might have needed to become more of a SM in that case).

49 minutes ago, PB666 said:

No in space repair, no manned capability, no satellite return capability, no capacity to assemble space stations

Over rated capabilities, honestly.

Repair only really works if the spacecraft was designed with that in mind, and then it has to be in the right inclination and at the right altitude, and it has to be worth the cost of sending a crew mission to repair it. At 65M$ a launch, replacement for anything in LEO Shuttle could repair is likely more cost effective than a 1.whatever billion $ Shuttle flight.

Manned, well, you're right there.

Sat return? I'm unsure of the value there, honestly, but I'm sure there is some. Make a bag filled with expanding foam with a retro package, and chutes?

Assembling space stations? This is a chicken/egg issue. ISS required so much assembly precisely because the modules had to fit inside Shuttle. If the goal is the same habitable volume, send it up in 1-2 Shuttle C flights (or some HLV equivalent). Assembly is a product of tiny modules. <20t modules lofted in a 90 ton vehicle.

That said, I agree on having a manned replacement before killing the program, the trouble was money. The Shuttle and ISS budgets ate up all the $, so throwing real money at crew required killing Shuttle first.

5 minutes ago, CatastrophicFailure said:

Soyuz had two LOCV events... during development (Challenger and Columbia were both “operational” flights), and the Soviets learned from the mistakes and rectified the flaws. Soyuz also demonstrated the critical importance of launch abort capability, with two crews saved (one on the pad and one at high altitude, IIRC the latter outside the shuttle’s survivable abort window).

There’s calculated risk and unreasonable risk. Zero abort capability in the first two-ish minutes of flight and dicey prospects after till you’re nearly in orbit anyway, that is unreasonable. 

Soyuz was pretty operational in 1971, it was the 10th flight with crew and about as many unmanned.

Generally, I think that capsule designs are going to be safer than Shuttle ever was, the problem is characterizing the risk. I know commercial crew is having trouble making the 1:270 LOC requirement, but that calculation seems pretty hard to characterize well to me, honestly. Then Orion gets to literally fly people on the very first "all up" flight of the stack. For reasons.

 

[NSEP]

I like the idea of the Shuttle. A reusable spaceplane, capable sending and returning people and payloads to and from LEO. Isn't that awesome? The real deal however was not so nice. It was way too expensive for something that's supposed to be reusable, and quite dangerous and fragile.

It was definitely a cool gizmo, but its like an Iphone X, jaw droppingly expensive.

[CatastrophicFailure]

1 hour ago, tater said:

Sat return? I'm unsure of the value there, honestly, but I'm sure there is some.

IIRC, the shuttle only did this once. The capability was mostly there so the Air Force could “borrow” Soviet satellites for a looksee. 

The one time this really would have been awesome, returning the Hubble to put in the Smithsonian, and the shuttles are already de-funded and retired. 

[Nibb31]

STS was a huge technological accomplishment, all done with 1970's technology, and I believe that Crippen and Young had balls of steel to climb into that thing for STS-1 because there were so many things that could have gone wrong. Everyone who worked on the STS program and flew on the Shuttle deserve the utmost respect.

The problem with the Shuttle was that it was an experimental vehicle made operational. It demonstrates what happens when your project is too ambitious. It really should have started as a X-something and then evolved into an operational vehicle, like the X-33 tried to be. Instead of planning a fleet of Shuttle Orbiters from the start, there should have been an evaluation period operating Columbia and Challenger for a few years, followed by an all new Shuttle 2 design.

The STS used many unproven technologies that were experimented for the first time and all needed to be 100% operational for the vehicle to work.

• First man-rated solid booster
• First side-mounted payload
• First winged reentry vehicle
• First runway landing from orbit
• First reusable TPS
• Largest TPS
• First reusable engines
• Largest reentry vehicle
• First vehicle combining crew and cargo
• And the list goes on...

And this is why I don't believe in projects like Skylon or (to a lesser extent) BFR. They are both projects that accumulate too many new unproven technologies and which rely on all of these technologies working flawlessly for the whole project to meet requirements.

Edited January 15, 2018 by Nibb31

[Nibb31]

1 hour ago, CatastrophicFailure said:

IIRC, the shuttle only did this once. The capability was mostly there so the Air Force could “borrow” Soviet satellites for a looksee.

Although this was an envisioned mission, it would have been stupidly reckless and dangerous.

• Planning a reentry profile requires being certain of the mass and layout of the payload, as well as designing a custom-built cradle for the payload, which means that you already have detailed plans of it, which means that you won't gain much in bringing it back.
• You have to assume that any top secret military satellite is likely to be booby-trapped or at least equipped to prevent tampering.
• The whole thing would be an extremely hostile action, akin to boarding and stealing an enemy warship, and likely to start a war.

[Bill Phil]

1 hour ago, CatastrophicFailure said:

IIRC, the shuttle only did this once. The capability was mostly there so the Air Force could “borrow” Soviet satellites for a looksee. 

The one time this really would have been awesome, returning the Hubble to put in the Smithsonian, and the shuttles are already de-funded and retired. 

It actually returned satellites at least twice. Palapa B2 and Westar VI ( on the same flight, I think...?) and later retrieved the LDEF from orbit.

https://en.m.wikipedia.org/wiki/STS-51-A

https://en.m.wikipedia.org/wiki/Long_Duration_Exposure_Facility

[PB666]

4 hours ago, tater said:

I agree on having a manned replacement before killing the program, the trouble was money. The Shuttle and ISS budgets ate up all the $, so throwing real money at crew required killing Shuttle first.

But that was more of a congressional issue, not a NASA issue. NASA's budget was not spectacularly high, in fact toward the end it was low compared to GDP. At least I agree with this, but not simply that all functions. The shuttle was experimental technology made operational with largely 1970s technologies and could have been redone far more efficiently preserving most of its capability after the ISS was finished even excluding the possibility that we can launch another Hubble.

The problem is that over time the contractors serving NASA were not become more efficient and there is no guarantee that a recyclable vehicle would have saved that much money if it was engineered.
Here is the basic problem with engineering. . . . we have to consider an overriding feature of the shuttle was the sheer size of its equipment bay (4.6 by 18 m) this made an ideal carrier for scientific satellites which were often bulky because of the nature of the equipment. Even so with a PL to LEO of 27 kT you are sitting at the very high end of capability, that has to be added, on top to the ability to carry up to 11 astronauts back to Earth.

It would be my opinion based on the types of problems needed to solve for deep space flight that a larger volume payload would be better, not smaller. Its ability to pack and unpack stuff from payload bay make ideal for carrying bulky solar arrays (not for ISS) that can be used for interplanetary missions. For example, with current technology, the only vessel capable of building an interplanetary space tug would be the Shuttle, only the shuttle has the extendable arm and a payload bay long enough to carry the types  of panels required for such a mission AND can assist and astronaut crew capable of assembly. Without a tug getting stuff back and forth from Mars is going to be prohibitive, IMO. And I know we are going to here this argument about the DSG, the problem with DSG and like-systems . . . vaporware. In my experience if something is doable and feasible its going to be execute within sizable completion in 5 years . . . . its not happening.

STS evolution
So its not only what the space shuttle has done, but what it could do in the future. Another problem that I see is the complaint about the Engines. So somethings I would point out that I would change.
1. SFRBs . . . .no really efficient launch vehicle really uses these anymore, and the ones that do use small ones, just enough to get to close to MAX Q. These should have been replaced with F9 like returnable rockets. The SFRB recycling was a boondoggle, and SpaceX demonstrates how it should be done.
2. Payload bay could be widened without necessarily effecting overall performance. I would have been nice to have a shuttle with a wider bay. The future of deep space until a efficient fusion reactor can be designed is bulky structures. Length I don't think I would mess with.
3. The RS-25s unfortunately, and I say this very cautiously, required to much maintenance per cycle, the production cost, trivial compared to the number of missions, I wouldn't touch that be there needs to be a way to allow them to operate for hours without significant maintenance.
4. Complete avionics flight control replacement, complete overhaul of extended duration life support capabilities.
5. The big red fuel tank, seriously there could have been structural adaptations to prevent icing, for the fact you are launching next to a beach next to the gulf stream, it carries heat from the gulf = moisture. This problem could have been dealt with removable plastics that could have been separated prior to launch. There were solutions available. The idiocy of this is that oxygen is produced on site for the shuttle . . .this means, guess what so is nitrogen its simply toss away, it could have been used to keep the exterior of the shuttle dry simply excluding moist air.
6. Ablation tiles . . .again these have been shown to be obsolete both in design and structure.

Replacement
First off the Orion system IMHO is too specialized, it looks back to the Apollo era and not forward and it has taken too long to design and has proven to be rather expensive. So I don't see Orion as a comparable replacement but as a tangential system. More and more it looks like a boondoggle. There is no need for a vehicle to be able to go to Mars and whereever and also reenter the earths atmosphere. These capabilities can be taken care simply by crew transfers, The orion reentry capability is kind of a waste of function capabilities.
The SpaceX Crew transport system is very utilitarian and does fill in a gap that the US has been lacking and is likely to be a cost reduction over the shuttle, obviously this, if it works will be required . . .no doubt..But expect glitches.
Missing: is an in space repair capability outside of the ISS elliptical.
Missing: is an in space assembly facility (a factory) or the means to build it. Im not saying that the shuttle is best for doing this, but its a magnitude better than the next best thing . . . . . Deep space ventures and tugs will require this.
Bulk cargo carrying capacity  . . . . .compromised . . . .I don't see a future for DIV heavy. Maybe space X or the Russian rockets can pick up the slack.
Extended range multipurpose vehicle. Obviously the vertical range limited the shuttle, and its looks like SpaceX is working toward in space refueling (currently they cannot handle LH2. This needs to be a thing.
    a. First its hard to imagine a mars resupply and sample return without a dedicated (i.e. Earth MEO or GTO to Mars ) shuttle, the refueling needs at Mars are pretty significant and we can't expect Mars to be big fuel producer. There needs to be a way to get some sort of equipment carrier up to MEO that either it or something else assembles>
   b. of course the assembly may require its own specialized and dedicated facility (once it is built)
   c. some ability for the shuttle/replacement to be refueled in space. If spaceX is cheaper at getting m ->LEO then why not let them do it in spades.

There are many pieces here that need to be replaced, not just manned to orbit if your are looking future. As stated in other thread ISRU is mid to far future, most of the things I mention need to already be a thing for stable and expansive deep space presence. Its not about the shuttle or its design, its about extending functionality into space up to a point where this idea of fabricating interplanetary vehicles with Earth return capability is routine and something more evolved than Hayabusa (the Odysseus of the spaceflight saga). It is sad for NASA that not only did they loss what they had, but since then progress has been virtually frozen. And in terms of the cost NASA is a victim of greed as well as their own inefficiency, so the point needs to be made that NASA needs funding to handle near future progress.
 

6 hours ago, CatastrophicFailure said:

Soyuz had two LOCV events... during development (Challenger and Columbia were both “operational” flights), and the Soviets learned from the mistakes and rectified the flaws. Soyuz also demonstrated the critical importance of launch abort capability, with two crews saved (one on the pad and one at high altitude, IIRC the latter outside the shuttle’s survivable abort window).

There’s calculated risk and unreasonable risk. Zero abort capability in the first two-ish minutes of flight and dicey prospects after till you’re nearly in orbit anyway, that is unreasonable. 

This is an artificial argument, why the first two minutes. And what exactly does the Soyuz do that SpaceX will not be able to do cheaper, the capabilities are not moderness, they are basically primative.

[sevenperforce]

9 hours ago, GoSlash27 said:

Things have evolved since back when the shuttle was on the drawing board. Back then, the best way to get a vehicle where you wanted it was with a pilot and wings. Times have changed.

True. Which is why for its time, the Shuttle was the only way to deliver a crew-and-cargo vessel back to terra firma.

I wonder. If the SRBs had been replaced with LRBs powered by paired F-1 engines (which, at the time, wouldn't have been too hard to manage), just imagine how much more the system could have done! The orbiter would have had margins for jet engines and for a jettisonable, independent-EDL-capable crew cabin with dedicated solid escape engines, and could have gotten away with only a single pair of SSMEs (which could have had more margins for reuse and not been quite so cutting-edge). The boosters wouldn't have been recoverable, of course, but the Shuttle SRBs didn't exactly save money via reuse. 

9 hours ago, PB666 said:

The bulk of the shuttles thrust was provided by LH2LOX and three very efficient engines, so it was relatively more efficient than FH would be, someday, maybe, if it can standup strait for more than a few hours.

I think the positing of scientific and in-space operation capabilities, unfortunately, goes on largely deaf ears here.

The bulk of the STS thrust was provided by the SRBs. The bulk of the energy to orbit was provided by LH2/LOX and the SSMEs.

The scientific and in-space ops were tremendous; don't get me wrong. Each orbiter essentially WAS a space station. But those operations were hampered by a launch system which was ridiculously unsafe, filled with pork, and only narrowly refurbishable (let's face it, the STS was not "reusable" in any immediate sense). 

A Shuttle rebuilt today with methalox main engines and kerolox boosters would be super-capable. But back then, they were barely squeezing by to have an operational launch system at all.

7 hours ago, CatastrophicFailure said:

Soyuz had two LOCV events... during development (Challenger and Columbia were both “operational” flights), and the Soviets learned from the mistakes and rectified the flaws. Soyuz also demonstrated the critical importance of launch abort capability, with two crews saved (one on the pad and one at high altitude, IIRC the latter outside the shuttle’s survivable abort window).

There’s calculated risk and unreasonable risk. Zero abort capability in the first two-ish minutes of flight and dicey prospects after till you’re nearly in orbit anyway, that is unreasonable. 

No 0-0 pad abort. No Max-Q abort. No passive aerodynamic stability for most of the ascent. A re-entry which requires literally every system to work perfectly and depends on dogfight-level piloting for basic energy management. A single shot at landing. It's a wonder we never lost a crew on landing, honestly.

7 hours ago, tater said:

@PB666, regarding Shuttle capabilities, I think that while you are right that Orion and Commercial Crew lack these capabilities, many are more valuable in theory than reality. Regarding delays, shuttle was delayed as well, then it blew up, and was delayed some more.

If we actually needed the large cargo delivery capabilities of the Shuttle, then surely some agency would have paid for the development of an expendable hypergolic-equipped orbital maneuvering bus that could fly on a Delta IV Heavy or other MHLV along with a high-volume cargo. We have the technology; you basically just need a service module with extra fuel tanks, or something like the Dragon 1 without the internal cargo space or the re-entry shell.

The fact that NO money has gone toward development of something like this is a pretty good indication that the Shuttle's "payload delivery" capabilities were not really that necessary.

[wumpus]

9 hours ago, PB666 said:

The bulk of the shuttles thrust was provided by LH2LOX and three very efficient engines, so it was relatively more efficient than FH would be, someday, maybe, if it can standup strait for more than a few hours.

I think the positing of scientific and in-space operation capabilities, unfortunately, goes on largely deaf ears here.

Shuttle Solid Boosters: 25MN thrust (125 seconds of thrust)
SSME (all three engines) 5.25 MN thrust total (455 seconds of thrust)

Not even close to the "bulk of the thrust".  Even "bulk of the thrust*time" is about dead even.  Certainly the SSME provided much more delta-v,  but not by providing significantly more thrust.  I wonder if this is a corollary to the "all spelling/grammar flames will contain spelling/grammar errors of their own".

If you want thrust from hydrolox [from the pad] go with a delta heavy.  Just don't expect to send any astronauts on it, nor get the price down anywhere near spacex.  Hydrolox might be efficient, but fuel is cheap and optimizing for fuel is silly.  Kerlox makes so much more sense for a first [especially expendable] stage that the Delta IV rocket's future is in doubt (NASA/DoD are replacing anything they can with Atlas).

[tater]

At SRB sep, the shuttle was only moving at 1.4 km/s. So while most of that was achieved by the SRBs (thrust), the bulk of the delta v of Shuttle was in fact from the SMEs.

Everything @Nibb31 said was spot-on. Shuttle was a great accomplishment, and the idea of it as an x-vehicle, with substantially improved follow on vehicles would have been a far, far better use of resources. In that counterfactual history, we'd still be flying an ancestor of it now I'm sure.

[sevenperforce]

13 minutes ago, tater said:

At SRB sep, the shuttle was only moving at 1.4 km/s. So while most of that was achieved by the SRBs (thrust), the bulk of the delta v of Shuttle was in fact from the SMEs.

Indeed. But by Oberth, the dV in that big orange tank is FAR higher at 1.4 km/s than at 0.0 km/s. There was more dV in the ET at sep than there was at liftoff.

27 minutes ago, wumpus said:

If you want thrust from hydrolox [from the pad] go with a delta heavy.  Just don't expect to send any astronauts on it, nor get the price down anywhere near spacex.  Hydrolox might be efficient, but fuel is cheap and optimizing for fuel is silly.  Kerlox makes so much more sense for a first [especially expendable] stage that the Delta IV rocket's future is in doubt (NASA/DoD are replacing anything they can with Atlas).

From a dry mass efficiency standpoint, the ideal launch system is something like kerolox boosters crossfeeding LOX to a methalox core topped by a hydrolox upper stage with hypergolic OMS.

EDIT: If you replaced the SLS SRBs with Merlin kerolox boosters, crossfed the LOX tanks to a Raptor or BE-4 core, and topped it with a vacuum-expanded BE-3 upper stage with Draco-based OMS, I wonder how much smaller than the SLS it could be and still have the exact same capability.

Edited January 15, 2018 by sevenperforce

[tater]

Yeah, the component from the SSME sustainers increased every second of flight.