Is SLS Going To Be The Biggest Rocket – Evah?
Keith’s note: Let’s see: Saturn V was 363 feet tall and weighed 6,540,000 lb. SLS Block 1 (the only rocket this budget supports) is 322 feet tall for crew version and 313 feet tall for the cargo version and weighs 5.5. million lb. SLS Block 1 can put 209,000 lb in to LEO and Saturn V could put 310,000 lb into LEO. Oh yes a totally expendable Falcon Heavy can put 141,000 lb into LEO. You can buy a bunch of them for the same cost of a SLS. Then there’s the Soviet N-1, and the upcoming Blue Origin New Glenn and SpaceX Starship – both of which may be operating before the fully upgraded SLS. Jim Bridenstine said “We’re talking about a rocket that’s bigger than any rocket that’s ever been built in human history”. So … is SLS bigger than any rocket in history? Not so sure about that. Paper rockets don’t count. Just sayin’. Larger image
"We’re talking about a rocket that’s bigger than any rocket that’s ever been built in human history …" says Administrator @JimBridenstine about @NASA_SLS during #Moon2Mars event pic.twitter.com/TDd9rOIJ2m
— NASA (@NASA) March 11, 2019
Everything about that rocket development annoys me. Why is it taking them so long and so much in cost bloat to build it out of almost entirely existing hardware? They’re literally re-using shuttle engines, shuttle SRBs, a shuttle external fuel tank – shouldn’t this all be hardware they understand extremely well after 30 years, and can quickly adapt to a modified expendable configuration?
Or is it Orion that’s causing all the delays?
Questions asked by many here for many years, and with no answers, not a single example “X has taken longer because Y.”
This is a second hand report: A few months ago I was in Mexico enjoying a bit of time off. Two guests at the same resort, as it happened, were design engineers working on some part of SLS. I was thrilled and peppered those two with questions until they started to avoid me…
But the stories they related all contained something about morale, and all were just heartbreaking.
And that’s the thing: some of our best and brightest, working on SLS, know that the future for the program is unclear, but dim.
A disillusioned workforce. It’s just bad policy.
This sounds all too depressingly familiar, and reminds me of my previous life/bad old days working as a systems/software engineer in aerospace. Management always seemed to be three things: clueless, would never deign to actually TALK to people doing the real work, and at least 10 years behind the times in any kind of management methods.
That’s one thing that’s clear from the enthusiastic crowds in the background at every single SpaceX launch: Elon may be eccentric, but he has a clue how to manage and motivate a workforce well.
That is not surprising as they are being forced to recreate a relict from the 1960’s instead building a modern launch system like the engineers at Blue Origin or SpaceX are doing. At best it will only make a couple of test flights before being killed. It reminds of the crazy Princess Flying Boat the English wasted their engineering talent building in the 1950’s. It is almost criminal to waste fine engineers that way.
“Why is it taking them so long and so much in cost bloat to build it out of almost entirely existing hardware? They’re literally re-using shuttle engines, shuttle SRBs, a shuttle external fuel tank”
LOL to congress those are all FEATURES!
I keep seeing this misinformation everywhere.
The external tank tooling was destroyed after the end of the shuttle program to make way for the Ares program. Because of this, the SLS core is being made with all new tooling (like that fancy vertical welding tool that was not installed plumb and had to be reworked).
The SRBs aren’t reused, only the steel casings. The five segment SRB is a new rocket booster. I can’t remember all the other tweaks made to the SRBs besides deleting the parachutes and other recovery hardware and changing the material used as insulation between the propellant and the casing (this change caused problems which had to be addressed).
The SSMEs aren’t even exactly the same because they required an all new engine controller. This meant that the new controller had to be qualified, which is why we’ve seen lots of SSME test firings over the past few years.
Because of the above changes, one new MLP was built (with another to be funded), all the shuttle work platforms in the VAB had to be replaced with new ones for SLS, and etc. Lots of ground infrastructure had to change and all those “little” changes take time and money.
The fact is that while SLS bears some resemblance to some of the space shuttle parts, it’s really a new design. That’s why it’s taking NASA so long and so much money.
And let’s not forget that the old tooling would be useless as the extetnal tank had to be redesign to take the stress of putting the upper stages on top of it and the rocket engines under it. The dynamics are completely different than hanging an Orbiter off of it. It is a brand new rocket with all the risks that implies.
The NASA engineers who worked on DIRECT disagreed with this assertion. From what I understand, the ET didn’t use fixed thickness for every part of the tank. So the ET tooling was already capable of making various thicknesses of tank material. Because of this, DIRECT could use the ET tooling to make a tank that was still within the specs of the tooling, even though it was thicker and stronger in many places than the external tank.
Except it couldn’t. You couldn’t weld that thickness. As Boeing found out.
—
DIRECT was always a bad concept. The idea that you could repurpose hardware from such a finely bespoke system as STS never made sense. Lego rockets are fine, but first you need Lego. You can’t turn a hand-crafted, single purpose system into general purpose building blocks. Saturn 1’s precursors were Lego bricks. Robust, lots of margin. STS was a house of cards, delicately balanced against its own deficiencies. Not robust. Not repurposable.
Was it necessary to go into production before these lessons were learned?
You mean the second half (main part) of my post? No. STS was always fragile, ragged edge, barely functional (In the sense that the engineers pulled a freakin’ miracle. STS shouldn’t have been able to fly.) The simple proof was in how difficult every single change had been in the history of the program. Small upgrades were hard and expensive. Big upgrades, that should have been seen as routine over 25+ years of ops, things like Shuttle-C, liquid-boosters, etc, were treated, internally, as if they were proposing an entirely new launchers. (Hell, to some extent, it was easier for them to contemplate an SSTO than an “simple” STS upgrade.)
If you were just replying to the first sentence? Probably not. But every part of SLS changed the STS hardware into new territory. They should have expected a bunch of such cases (especially on the back of Ares throwing up the same kinds of issues.) The insiders who said it would save money were IMO lying. Not “mistaken”; lying.
Shuttle-C could have been developed faster and cheaper (especially if it had started early enough) and still had somewhat comparable lifting capacity, at least compared to Block 1. And it would have likely had a higher flight rate than SLS (a pretty low bar of course).
However it couldn’t have launched Orion, and we just can’t have Orion launched on anything but a Shuttle- derived launch vehicle, now can we?
True, but Shuttle C (or any flavor of DIRECT) would have needed to have been started before Ares I and Ares V became a thing. Because it was the Ares program which pretty much decreed that all space shuttle external tank tooling needed to be destroyed to make way for the larger diameter core stage tank of Ares V. Also, Ares I needed the five segment SRB, so that was completely reworked as well.
SLS is just a warmed over Ares V. Pretty much all commonality with the space shuttle was lost with Ares.
Agreed and that was actually my point when I mentioned starting early enough. Shuttle-C was the only potentially viable derivative of the problematic and aging Shuttle hardware because it required the least amount of design modification. That did mean that Shuttle-C would not have been scalable, but since Shuttle had been overbuilt, or let’s say overambitious in its lifting capacity, that meant Shuttle-C would have been a pretty decent lifter.
But the moment you start making changes, even something as seemingly innocuous as adding a segment to the SRB’s, you might as well be building a new rocket. You would never do that with an old computer system, imagine a company that has an old computer running their production software. They get a new software and find that it will run on the old hardware, so okay let’s save money and use the old hardware even though it’s a little slower and harder to maintain. Pros and cons but it would be an option. But what if the new software required higher processing power, more memory, more storage, etc. beyond what the old hardware was originally designed for. No one would think of trying to upgrade the old computer system. Yet that’s what they tried and amazingly are still trying to do with the vintage 1980’s Shuttle hardware, which actually predates the IBM PC (Shuttle April 1981, PC August 1981).
It’s hard to imagine anything slower and more expensive. But I suspect it would still have been worse than a clean-sheet design. The STS hardware just was not suitable to being changed.
That said:
While Shuttle-C as derived in the ’80s couldn’t have carried Orion. There would be nothing particular preventing an expendable cargo side-mount from carrying a capsule on top.
Compared to other alternatives (including clean-sheet) yes but I was comparing to other Shuttle-derived vehicles. Even the simpler Ares I was having its problems just from adding the extra SRB segment (because of overweight Orion), and they were making more changes to the SRB’s than just that. And I don’t think they even got close to building the upper stage, who knows what problems they would have run into with that. Now if Shuttle-C had required major mods to the ET or SRB’s then yes it would have suffered the same fate.
Orion on top of a cargo module, I never thought of that arrangement. I wonder if for capsule only launches they would have needed some ballast in the cargo module since even an empty Shuttle weighed three times more than Orion.
That configuration (Orion on top of an empty Shuttle-C cargo unit) might require some ballast, but I’d object to inserting dead weight. You can almost always find something more useful to use as ballast. Actually, even if you don’t think very hard about it. One thing I was told when I grew up in Washington (possibly an urban myth) is that some of the cobblestone streets in Georgetown are paved in ballast. Ships returning from California to Baltimore were in ballast, and someone decided to sell off the rocks.
And in practice it would have. That was my point. STS was not, in spite of its appearance, a “lego” design. Everything affected everything else. Whether thermal or loading or aerodynamics. Seemingly isolated parts were not.
Put it another way, if the STS-stack was capable of being converted into Shuttle-C side-mount style cargo vehicle, IMO it would have been done when it was first proposed in the ’80s and early ’90s, instead of X-33.
Even if it wasn’t the full Shuttle-C capability, just a sled with disposable engines and a separate upper-stage with a normal fairing, created as a demo to show the viability of Shuttle-C and to allow continuing non-crew launches after Challenger, and as a test system for changes to the stack (post-Challenger).
It just seems like if it was as easy as the proponents claimed, hell if it was merely ten times harder than they claimed, it would have been so much easier than any other proposal (including the risk of returning-to-flight without an unmanned test capability), that it would have been done.
—
Energia seems like it was a more “Lego” design for a shuttle-stack. Which is why the cargo version was possible. I don’t know how practical that was in reality. It was a failed project, but occurred at a stage when the Soviets were bankrupt, so was bad design or bad funding?
Similarly, SpaceShip/SuperHeavy seems like a Lego rocket, but will it turn out to be in practice?
—
Heh. Not once the Orion designers are done with it.
Snark aside, you have to allow for the engines/OMS(*)/etc of the cargo section to replace the Orbiter, plus the mass of “Orion” must include the service module. Oh, and the fact that you aren’t just launching into LEO, you need to compare BEO throw.
*(Or add an upper-stage.)
Are you saying then that they needed to develop new methods and materials to recreate the old designs? 🙂
BTW the “hopper” version of the SpaceX Starship was moved to the launch pad Friday and Elon Musk has indicated static firing tests could be starting by the end of the month. Plans are to start construction of the orbital test vehicle (Starship and Super Heavy) in weeks. At 1.5 times the thrust of the Saturn V it will blow everything away.
From the pics and videos posted yesterday, it looks like they might have done a cold flow test (liquid nitrogen?) on the hopper’s plumbing and tanks.
Wouldn’t be surprised. Elon Musk wants the Starship/Super Heavy ASAP to cut his costs deploying the Starlink Constellation so he is going wrap speed on it. He is likely to be doing the static firing tests before the damaged nose cone is replaced, since it’s not required until the hopper actual starts flying. I am sure NASA and Old Space engineers will be having fits when that happens because that is just not how you build and test a rocket… After all, where are all the Power Points? The Staff meetings? The paperwork documenting the paperwork of the work being done?
And why is he building it out of stainless steel, out in the open, using workers who normally build water towers?!?!?!?!?
Not everything that flies into space has to be made of aluminum-lithium alloys, titanium, and carbon fiber composites. Better (more expensive) is the enemy of good enough (cheaper).
Have they said these are orbital test vehicles? I was thinking a Super Heavy hopper will be built first and I suspect that is what is meant by “flight article design” in the tank fabricator job posting. Unless I missed a tweet somewhere, I wouldn’t expect construction of orbital test vehicles to start until Commercial Crew is up and running, since Elon stated previously that that is when the majority of development resources will be shifted to Starship.
That being said, the crew Dragon test flight went extremely well, and if the remaining test flights go equally well, and if the hopper tests are successful, Starship orbital test flights could start within the general time frame of the EM-1 launch. A lot of ifs however between now and then for both programs.
it’s certainly the largest amount of money spent to deliver a rocket, so in that sense it’s the largest rocket ever….
KC’s comment is precisely correct. More kabuki theater by NASA.
No one can be surprised with the lack of precise and factual use of the English language when most anyone in this administration says anything that may confront their world view, ego or narcissistic tendencies.This human behavior should be more disturbing then the inevitable short comings of the SLS.
NASA PAO has ignored reality, including NASA’s own history, through many administrations. I wouldn’t be surprised if Keith’s second post back on RIFWatch was mocking the PAO.
To be fair, and POTUS45 notwithstanding, generalized obfuscation is part of any administration, from either party.
To me the latest news is the words lunar lander are becoming more common in various articles. The big break through would actual construction of a human rated lunar lander, or at least a major contract awarded (and hope will will not take decades like the conical capsule).
You can have the yuggest rocket evah but if no lander, you ain’t going to the moon.
Or, as at least one has proposed, you could actually land said rocket ship.
Ok, I have a question. Arabsat 6A is only 6000 kg, but FH will throw 26,000 and some change to GTO. So is this coming FH launch taking Arabsat all the way to its target orbit at GEO?
(all of my numbers above are from Wikipedia)