Why Derived?

guest blogger john hare

In the ongoing discussions about NASA’s proper direction for the future, you constantly see the phrase ‘Shuttle derived’. It is an acknowledged requirement to keep as much of the current workforce employed as possible, while forging ahead with hardware with a track record. The current program of record seems a kludge. The Griffenschaft Aries I, and the Aries V are Shuttle derived about like rebuilding an airplane around the ID plate.

The country started manned spaceflight with a series of capsules with some family resemblance. Then went a different direction with the Shuttle. Now a different direction again with the Constellation program. Starting fresh every time things don’t work out is what Henry Spencer would refer  to as “The Wile E Coyote School of Engineering.” Even beyond the Apollo-Shuttle-Orion discontinuities are the grand programs between that didn’t make it to prime time. VentureStar and company.

This post is from an outsider trying to see things from a NASA perspective. My brand is commercial, but the national program is the elephant in the room.

What if NASA had gone with it’s strengths five years ago with a vehicle series that it knew worked. It’s strength was the Shuttle series and orbital assembly, backed by a solid work force and decades of experience. In the Shuttle system, the external tanks and SRBs are known quantities that have reached a peak of perfection in decades of experience and improvement. The orbiter itself is the component that is aging and must be replaced. Why was it politically wrong in 2005 to call for building a new series of orbiters to make full use of every existing system with the infrastructure and experience base that stood behind it?

If the call had been for a new orbiter in five years and then another every three years until a new fleet existed, how could it have been worse than what is happening now? Use the experience and motivation of the NASA and contractor employees to improve the new series so that they could more closely approach the original proposed  flight rates. Eliminate whole systems that cost time and money to turn around in favor of more modern solutions. The first new orbiter would arrive just as the old ones retired. No gap, and no work force shuffle.

To get the first new orbiter in five years the way things are done now would have required compromises. I would say that the first new airframe would be for what Jon refers to as PPP, or people, propellant , and provisions. Since the main purpose of the new vehicle would be to supply the completed ISS, and later the exploration missions, many systems could be eliminated and the airframe simplified. The arm, hypergolic propellants, orbital endurance, and even the  toilet could be eliminated for the up and back fast turnaround requirements.

I’ve read that the electronics are impossibly out dated, but don’t actually know that. More modern stuff would almost have to be better if it was built in from the start.

Eliminating the large bay doors for a relatively small cargo hatch allows for a stronger and lighter airframe, which eases reentry heating, and increases payload. Along with the other eliminated systems, it seems possible that the new orbiter could carry double the net payload to ISS. Integration time for PPP can be held to days or even hours instead of the months currently mentioned. Simplifying also helps with the relearning process of building the new airframes.

XCOR and probably others were working on safe kerosene/oxygen orbital maneuvering systems several years back. Eliminating the toxic hypergolics should cut orbiter turnaround time considerably.

Engage the employees of the Shuttle work force to find the bottlenecks in turning the orbiters around. Where do new access panels need to be? Where would hand holds and ready platforms speed up the process?  Which processes are just a waste of time? Use the knowledge to improve based on experience.

The first new airframe should be able to fly every couple of months if done well. The second airframe would have eight years from go to duplicate the capabilities of the current orbiters with bay doors arms and all. By the third new airframe, it’s exploration time.

The  Shuttle class for exploration could be optimised to do the things that Orion capsule is supposed to do for long duration, and carry a  lander in the cargo bay. It could be designed to stay in space after launch with the main engines detachable on orbit, and with  wings and TPS left on the ground.

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I do construction for a living and aerospace as an occasional hobby. I am an inventor and a bit of an entrepreneur. I've been self employed since the 1980s and working in concrete since the 1970s. When I grow up, I want to work with rockets and spacecraft. I did a stupid rocket trick a few decades back and decided not to try another hot fire without adult supervision. Haven't located much of that as we are all big kids when working with our passions.

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About johnhare

I do construction for a living and aerospace as an occasional hobby. I am an inventor and a bit of an entrepreneur. I've been self employed since the 1980s and working in concrete since the 1970s. When I grow up, I want to work with rockets and spacecraft. I did a stupid rocket trick a few decades back and decided not to try another hot fire without adult supervision. Haven't located much of that as we are all big kids when working with our passions.
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17 Responses to Why Derived?

  1. mike shupp says:

    1. It cost 2 billion dollars to build a replacement orbiter back in 1987-88, when the dollar was worth rather more than today, and when a workforce which remembered building orbiters could be assembled and when manufacturing jigs, etc., were still available. That workforce is gone; those tools and jigs and assembly platforms are gone; that 1985 dollar is gone. Building another orbiter in 2005 or so would not have been cheap or easy. Likely it would have cost 4-5 billion dollars in current terms, roughly the cost of designing the Ares I rocket.

    2. The shuttle was a kludgy design in the 1980’s and beyond the problems revealed by two fatal accidents, has other serious problems — fragile wing leading edges, fragile and hard-to-attach tiles, poorly accessible cable runs and other maintenance headaches, potentially troublesome OMS engines — which have not been resolved at the present day.

    3. Simply trying to duplicate a 1980’s-vintage orbiter would be difficult enough. Trying to build an improved orbiter with more modern materials, electronics, control systems, etc. and the sort of structural modifications you’d like, would essentially mean designing, building, and testing, a (almost) brand new vehicle. This would be true for each of the proposed follow-on vehicles.

    In other words, building an “improved” shuttle and following up at regular intervals with ever more improved shuttles looks like a natural. In practice, it wouldn’t be, because each of these vehicles would be one-of-a-kind versions, and we can’t risk sending unique vehicles into space without elaborate testing. If, however, we had a space program big enough to build say 5 new orbiters every 3 years, your idea would be gold.

    4. Rule of thumb, electronics in a “modern” aerospace vehicles in the 1980’s cost about 1/3 of final vehicle cost. Whether things are different now, I don’t know, but it wouldn’t surprise me if the figure is about the same (there’s more to do with computers in current flight vehicles, but computer hardware costs do fall over time).

    (I don’t claim to be an expert on all things in space, but I did work as an engineer on the shuttle for about 6 years back in the 1970’s and early 1980’s. Some things have stuck in my memory.)

  2. john hare says:

    1. Some estimates are that $9B has already been spent on Aries I, and that it will take a total of $35B to get it into operational service. Your $4-5B sounds like a real bargain from a NASA viewpoint.

    2. Resolving as many of those issues as possible would be the point of the excercise.

    3. You are exactly correct and I agree. Compared to the current program of record though, doesn’t seem like it would have been a bad idea—five years ago.

    4. I don’t speak electronics, but a lot of friends do. I can accept your rule of thumb as accurate.

    Your six years of experience is approxamately seventy two months more than I have. 🙂 My prefered options would be for deliveries to be bid out more or less as the COTS program seems to be unfolding. This post was an attempt to see things though NASA eyes, with an idea of leveraging current assets as much as possible.

  3. D Wenzel says:

    This was the right answer post Challenger, not Columbia. If it had been followed then, by now, we’d probably have fully reusable SSTO or TSTO systems. By the time Columbia happened, it had become feasible (read not considered too crazy) to tender for crew and cargo launch services. NASA should now be focused on exploration ships that depart from the ISS (or another more convenient orbital base) and return to it. Reusable space or lunar tugs, nuclear ion deep space exploration ships, and the like, not capsules or heavy lift cargo launchers…

  4. “””” Starting fresh every time things don’t work out is what Henry Spencer would refer to as “The Wile E Coyote School of Engineering.” “”””””

    It’s also the Dan Snyder (Washington Redskins owner) school of team management!

    On a more serious note, while I personally see a lot of merit to your proposals, at the heart of the Constellation/Ares concept is the notion of returning to the Moon and eventually going to Mars. That was part of the reason for abandoning the spaceplane concept, I believe. Unfortunately, we live in an either/or funding universe when it comes to big space projects becuae of the obscenely high R&D and operational costs that NASA and the feds refuse to change.

  5. Nemo says:

    1) NASA’s 2004 mandate was to explore beyond Earth orbit and the shuttle can’t go there. There is an argument to be made in favor of “multi-modal transportation” – specialized spacecraft for earth-to-LEO and beyond-LEO – but don’t try making that argument at NASA. The position then (and now) was that NASA would not get the budget to do a second, beyond-LEO spacecraft in addition to upgraded orbiters. Since a beyond-LEO capsule would also be inherently capable of LEO, the choice is obvious.

    2) The shuttle’s vulnerabilities are inherent to the basic design. Sidemount makes crew escape dicey and places the spacecraft in a high-debris environment. The post-CAIB position at NASA was that the money required to significantly mitigate that would be better spent toward a system with fewer inherent vulnerabilities.

    3) No need for a large shuttle after ISS assembly complete. CAIB recommended separating crew and cargo and NASA took that and ran with it.

    4) There is a strong “capsule mafia” at NASA that has long bristled at the shuttle and the 107 accident gave them the opportunity to seize the reins. They are not interested in leveraging existing assets; they want to fundamentally remake the agency.

    5) $4-5 billion is per airframe. Does not include the startup costs, which would be even larger (especially with the redesign you’re talking about).

    There are probably other reasons as well but if you want to understand NASA’s motivations, especially in the post-107 accident period, you must grasp 1-4). Those are key.

  6. Kelly Starks says:

    Having been on both the shuttle operations and Orion development programs I assure you you have a excellent and overlooked option. most have no concept of how cheep that would be compared to aries/Orion. Adjusting all numbers for inflation, even though Orion is largely designed around shuttle upgrade systems, the Orion development program is currently expected to be about 20% more expensive the orbiter development program. Ares-I/Orion about 25% more then the STS development program. Given the extremely low flight rates projected, GAO estimates are that total costs per flight could be 8-10 times that for shuttle.

    >>Eliminate whole systems that cost time and money to turn around in favor of more modern solutions. <<

    Its not orbiter systems that generally take the time and money. Its access issues. Shuttle was developed on a tight schedule and budget, and as is normally the case, the "illities" like maintainability don't get the attention needed. Simply adding access panels and repacking systesm so they can be services without major teardowns of the orbiter would offer dramatic improvement. The DC-X program focused on that and demonstrated a roughly thousand fold reduction in labor hours per launch.

    Other upgrades proposed over the years such as alloy clad TPS (developed later for the X-33 program), enhanced long duration life support (developed more fully in the Orion program), and using the same fuel systems for the RCS and main engines could further expend capacities adn dramatically lower per flight time and costs.

    One other short cut of the current shuttle that could be eliminated is the external tank and SRBs. I once talked to someone who had been on the dev program in JSC. He said someone came into the office late on the Thursday and told everyone that by Monday morning They needed to have on Nixon's desk a redesign that will halve the shuttle development costs, and retain all the on orbit capacities, and cargo capacity. That Monday they delivered that, and the model showing the current kludgee design.

    If you replace the SSMEs with RD180s, stretch the hull about 30-40 feet to all a lox tank, and expend the wings proportinatly and fill them with Kerosene. You have a craft that can get from SRB septo orbit. Fly it in a biamese configuration, and it gets from the pad to orbit with no other system. Add in in-orbit refueling, and in space restart capacities, adn the long duration orbiter modifications Orion is copying,; and your orbiter can refuel and go to GEO or lunar orbits with a full cargo load.

    Assuming the new super orbiter development program costs as much as the old orbiter development program – your replacing Ares-i &V & Orion for less cost then Orion, and a on orbit refueling station. Given the high flight rate capacity implied with the above mods – supporting the refueling station with the shuttles would not be difficult.

    However this design has one killer fault that doomed it. Its to economical. No I'm not kidding. NASA public and congressional support is largely due to the money the programs spend in given districts. Ares/Orion are hugely expensive to develop and operate even at VERY low flight rates. That means money sent to those districts for ETs, SRBs, and a new Orion for each flight. A new shuttle that doesn't need any of that, eliminates the bulk of the programs political support.

  7. johnhare johnhare says:

    D Wenzel and Roderick,

    In a rational world, you would both be right. I am trying to visualize what NASA could have done within the political constraints. If the Aries/Constellation were on track, all arguments would be very different. To me, the orriginal concept should have made sense. If an unmodified SRB had been specified with the upper stage restricted to the actual capabilities, then it could have been tested in 2005-2006 with dummy upper stages at modest cost. All up test flights could be happening now, in a rational world.


    I am getting my mind around your points, may take a while. These may be considered interim thoughts until I do.
    1. The exploration vehicle could have been a payload bay vehicle carried to orbit without being required to be a launch vehicle in it’s own right. It seems that it could be done for considerably less than the current kludge, and considerably quicker.
    2. I don’t think a reasonable argument can be made against your point. The unreasonable argument is that NASA was already using the sidemount and might not successfully build the new systems, especially within budget.
    3. A large shuttle would have been large lift sooner for the exploration work. The CAIB reccomendations seem to be steering the agency down a dead end street.
    4. If they could successfully remake the agency, there would be no argument. It seems from where I sit that it has all become a turf battle with many losers and a small group that might break slightly better than even.
    5. It is only in the context of the current mess that I can even type that my suggestion would have been a good idea back then. I am seeing eventual numbers toward the $100B range. Given that, improving something they already know how to do seems quite respectable.

    Understanding the motivations is the target of this post. I can just barely glimse some of them. The country could have had an exploration program in full swing by now if all the players were rational actors fully motivated to explore instead of nearsighted victories.

  8. If NASA had simply developed the Shuttle C right after developing the space shuttle, just think how different things would have been today. The US would have had the ability to place the ISS in a more convenient orbit with substantially larger habitat modules. And most of the manned Space Shuttle cargo flights could have been eliminated.

    We’d already have the heavy lift capability to place large payloads into lunar orbit and we probably could have returned to the Moon back in the late 1980’s or early 1990’s.

    But its never too late to do the right thing. That’s why I strongly support the Sidemount concept because its the fastest and cheapest way to replace the current shuttle system and get us back to the Moon.

    And once this the new shuttle infrastructure is completed, NASA should have a tonne of money to play with afterwards if the current funding levels remain in addition to the expected (permanent) $3 billion dollar increase in the NASA budget. The shuttle retirement should give them $3 billion annually. The ISS retirement in 2016 should give them $ 2 billion annually. The completion of the Orion, Altair, and SD-HLV development should give them $6 billion annually.

    If we assume that operating the new vehicles and funding the lunar habitat program will cost at least $6 billion annually, that would still leave NASA with $5 billion in annual extra funds for developing the interplanetary infrastructure to place permanent habitats on Mars.

  9. john hare says:

    If the Shuttle C had been done back then, or even five years ago, then you would have a point. By now, so much time and capability has been wasted, that I fully expect events to overtake any internal capabilities NASA develops.

    The EELVs should be able to take a good share of whatever exploration gets done in the next decade, if properly managed. If improved like the owners of those systems could do when motivated, the C wouldn’t stand a chance.

    SpaceX and Orbital are already setting themselves up to take over the launching that NASA could have been doing. If they turn profits, they will expand to the point that NASA officials will have an uphill battle trying for funding for antiquated sytems.

    The sub-orbital start ups will have several years of fast turnaround experience well before a Shuttle C could be fielded from now. When they take the next step to orbital operations, all the low flight rate vehicles are in trouble. That could well happen in the same time frame as the sidemount vehicle became operational. Two or more RLV operators launching orbital flights once per week per airframe, would make the sidemount capabilities look somewhat foolish.

    Inflatable technology will have the better part of a decade to mature before NASA could possibly field a Shuttle C, which destroys the arguments for rigid large exploration volumes.

    This was very much a post of what could have been, not what should be.

  10. Daious vid Stever says:

    The Capsule Mafia? good description. When the various companies showed their basic designes, I was pleased with the small reusable flyable device they put forth. Unfortunately, NASA, after they had the 15 or so designs, showed what they wanted to be built, and the capsule mafia, like zombies walking up at the beginning of the movie, played their hands. I would have rather seen a small shuttle flying at the top of a launch stack, but the C.M. would not have that.

    Funny, if the Russians can break through their own capsule mafia, will be flying a small shuttle with their new craft. I am coming around to the notion that NASA has to to die for space flight to live.

  11. tom.cuddihy says:

    I’m certainly not in a position to know, but on the no-ET and even more from the no-SRB model it sounds rather far-fetched?

    Was there any detailed analyses on how feasible materials / margins were to support this kind of scheme? ( I mean, I could see this looking great on paper but then when the structures guys start subtracting tank volume for strength and the thermal guys start changing the shape of the hull to where your biamese vehicle looks like two whales belly to belly…

    Just curious, do you know are there any details on the design?

    Like I said, it sounds far fetched.

  12. jstults says:

    re: the ‘capsule mafia’
    The re-entry speeds are much higher for lunar and mars return trajectories. The big, blunt capsule is a robust design from a first principles, simplest thing that could work stand-point. Exquisite lifting bodies like the shuttle are fragile solutions.

    Calling it a mafia makes it sound like a conspiracy, which I guess is accurate if you mean high temp gas dynamics and robust design principles are conspiring against your scifi-inspired space-plane dreams.

  13. The problem with any winged vehicle is that there’s no escape for the astronauts in case of a launch malfunction early in flight. On the other hand, the shuttle has had a serious launch malfunction in over 23 years, a fact that I consider pretty darn safe. Protection of the thermal tiles (one fatal accident involving the tiles in 128 flights over 28 years) appears to be the only potential problem with the current winged shuttle which could be resolved with an inline configuration (placing a shuttle glider on top of a rocket booster).

    But there are still folks who want a manned space craft to be even safer by using a capsule with a LAS (launch abort system) on top. I have no problem with that. But while a winged space craft on top of a booster wouldn’t be– statistically– as safe as a capsule with a LAS, that still doesn’t mean that it wouldn’t be a lot safer than the current winged shuttle craft which, IMO, is pretty darn safe already.

  14. That should have read “the shuttle launch system hasn’t had a serious malfunction in over 23 years”.

  15. Kelly Starks says:

    > 11Marcel F. Williams
    > The problem with any winged vehicle is that there’s no
    > escape for the astronauts in case of a launch malfunction early in flight. ===

    Well you could have a ejection cabin like in some military craft – it was proposed for the shuttle – though how often can that save you?

    Actually, its been failures of the ET’s and SRB’s which killed shuttles. Cleaning up and toughening up the orbiters design, might make ejection systems unnessisary.

  16. kert says:

    Well, the “Not shuttle-C” was exploring the same path, while DIRECT went further and tried to eliminate some of the inherent flaws in the system ( sidemount )
    Stick a scaled-up X-37B on top of these Jupiter-xxx things, and you have your next “shuttle”.

  17. Kelly Starks says:

    Opps missed this one – sorry.

    > I’m certainly not in a position to know, but on the no-ET and
    > even more from the no-SRB model it sounds rather far-fetched?
    Its a old concept – not specific to the shuttle. Basically you replace the SSME with a LOx/Kerosene engines like the RD-180’s. the needed Kerosene is much heavier then the hydrogen, but eliminates most of the ET volume and tank weight. Store it in the wings and really you add no weight. Stretching the hull for the LOx tank, and dividing the LOx between the two craft, and it works out.

    > Was there any detailed analyses on how feasible materials /
    > margins were to support this kind of scheme? ==

    The brits did the origional studiesin the late 50’s, with current materials obviously its easier.

    I ran up some numbers on a Orbiter version if you want to see them email me at kellyst “at” aol.com.

    >== ( I mean, I could see this looking great on paper but
    > then when the structures guys start subtracting tank
    > volume for strength and the thermal guys start changing
    > the shape of the hull to where your biamese vehicle looks
    > like two whales belly to belly…

    No you just stretch the current hulls – and cylindrical LOx tanks and kerosene in wings, arn’t exotic tech.

    Really though if you figure newer materials, you could stretch it and still cut the orbiter dry weight 30%, and go with a much sleeker lower drag config. I posted details on that with a url to the ultramet web site ( ultramet “dot” com and select thermal protection systems) – but the post still isn’t showing up.

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