Expedition 48 Spacewalkers Restore Space Station Power Channel to Pre-2012 Configuration

The location of the Trailing Thermal Control Radiator (TTCR) on the outboard truss on the port-side of the space station. After its retraction, both of P-6's 2B and 4B power channels will be routed through the main Photovoltaic Radiator (PVR). Image Credit: NASA

The location of the Trailing Thermal Control Radiator (TTCR) on the outboard truss on the port-side of the space station. After its retraction, both of P-6’s 2B and 4B power channels will be routed through the main Photovoltaic Radiator (PVR). Image Credit: NASA

On a day which spelled calamity for SpaceX—as its Upgraded Falcon 9 booster, laden with Israel’s Amos-6 communications satellite, suffered a catastrophic failure during fueling at Cape Canaveral Air Force Station, Fla.—a pair of astronauts sailed smoothly through a lengthy Extravehicular Activity (EVA) outside the International Space Station (ISS). Expedition 48 spacewalkers Jeff Williams (EV1) and Kate Rubins (EV2) spent six hours and 48 minutes in the near-total vacuum of space, retracting and securing the Trailing Thermal Control Radiator (TTCR) and tending to several other important tasks. Their EVA comes only days before Williams and his Russian crewmates Alexei Ovchinin and Oleg Skripochka are due to return to Earth, aboard Soyuz TMA-20M.

Designated “U.S. EVA-37,” today’s spacewalk represented the 37th excursion in U.S.-built Extravehicular Mobility Units (EMUs) and conducted from the space station’s Quest airlock, without the presence of a space shuttle, since February 2002. It followed hard on the heels of the highly successful U.S. EVA-36 on 19 August, during which Williams and Rubins installed the International Docking Adapter (IDA)-2 onto Pressurized Mating Adapter (PMA)-2 on the forward face of the Harmony node. A subsequent EVA was timelined, but was brought forward following delays to Orbital ATK’s OA-5 Cygnus cargo ship—whose launch aboard the first Antares 230 rocket is now expected to occur no sooner than 13 October—and to Japan’s H-II Transfer Vehicle (HTV)-6, whose own target launch date of 1 October has been postponed, following the discovery of leaking pipework. This opened up a “window” of time in the Expedition 48 crew’s schedule to support a second EVA and thus put a number of important ISS maintenance tasks behind them.

Perhaps the most important was the retraction of the accordion-like TTCR. As outlined in AmericaSpace’s U.S. EVA-37 preview, this originally formed part of the Early External Active Thermal Control System (EEATCS) on the P-6 element of the Integrated Truss Structure (ITS). After installation in late 2000, it provided early ammonia cooling capabilities, before being retracted in early 2007, shortly before P-6 itself was relocated from the Z-1 truss to its permanent perch at the furthest-port “end” of the ITS. However, a very slow ammonia leak from late 2006 onward got progressively worse and necessitated the redeployment of the TTCR in November 2012 to provide interim cooling as engineers explored a suspected problem with the main Photovoltaic Radiator (PVR). At length, a failed Pump Flow Control Subassembly (PFCS) was identified as the root cause and replaced, allowing plans to be set in motion to once again retract the TTCR.

Expedition 45 spacewalker Kjell Lindgren works to restore the P-6 cooling system to its pre-2012 configuration during U.S. EVA-33 in November 2015. He and Scott Kelly ultimately left the Trailing Thermal Control Radiator (TTCR) fully deployed when the crew ran out of time and encountered other difficulties. Photo Credit: NASA

Expedition 45 spacewalker Kjell Lindgren works to restore the P-6 cooling system to its pre-2012 configuration during U.S. EVA-33 in November 2015. He and Scott Kelly ultimately left the Trailing Thermal Control Radiator (TTCR) fully deployed when the crew ran out of time and encountered other difficulties. Photo Credit: NASA

Despite its age, the value of the old radiator—nicknamed “the ticker”—as a high-priority spare makes it desirable to retract and cover it, thereby keeping it protected and in good condition, in the event that it is ever needed again. Last November, spacewalkers Kjell Lindgren and Scott Kelly successfully retracted the TTCR, but a combination of factors prevented them from fully cinching it down and closing its Micrometeoroid Orbital Debris (MMOD) shroud. As a result, it was redeployed, with the intention that its retraction would be tackled by another EVA crew in the fall of 2016. Delays to both OA-5 and HTV-6 have allowed that EVA task to be correspondingly brought forward.

In readiness for U.S. EVA-37, Williams and Rubins have spent the last several days collecting tools and reviewing timelines. Early Thursday, joined by their Expedition 48 crewmates Takuya Onishi of Japan and Anatoli Ivanishin of Russia, they spent about 60 minutes pre-breathing on masks in the station’s Quest airlock. The inner “equipment lock” was depressed from its ambient 14.7 psi to 10.2 psi, allowing them to check and purge their suits. The airlock was then repressurized back up to 14.7 psi, allowing Williams and Rubins to undertake a nominal pre-breathing regime on masks, followed by about 50 minutes of In-Suit Light Exercise (ISLE). Shortly afterwards, Onishi and Ivanishin transferred the fully suited pair from the equipment lock into Quest’s outer “crew lock” and closed the connecting hatches. Depressurization of the crew lock got underway shortly after 7 a.m. EDT.

With a scheduled EVA start time of 8:05 a.m., the crew and Mission Control worked ahead of the timeline and the spacewalkers transferred their suits’ life-support utilities to battery power and U.S. EVA-37 began at 7:53 a.m. Embarking on his fifth career spacewalk, Williams—identified by the presence of red stripes on his suit—was first to leave the airlock, followed in short order by Rubins, who became one of only seven women in history to have performed more than one EVA. As is customary immediately after egress, the duo set to work on “buddy checks” of each other’s suits, tethers, tools, gloves, and Helmet Absorption Pads (HAPs). Williams then headed along the airlock “spur” to the ITS, where he set tethers for himself and Rubins on the P-1 truss, before translating along the port side of the ITS to reach P-6 at the far end.

By 8:30 a.m., a little more than a half-hour into the EVA, both spacewalkers had reached the TTCR worksite, slightly ahead of the timeline. Williams positioned himself at the Earth-facing (or “nadir”) side of the truss, with Rubins at the space-facing (or “zenith”), and the pair conducted visual inspections to ensure that no debris blocked the retraction. Williams then set to work with a Pistol Grip Tool (PGT) and, within about 12 minutes, the TTCR had retracted into its stowed configuration. Rubins noted some possible MMOD damage to the old radiator, which was photographed, and a little after 9 a.m. the spacewalkers completed the installation of four cinches to secure the TTCR in place. Next, they removed wire ties and covered the radiator with its MMOD shroud, a task which was wrapped up by 10 a.m.

Jeff Williams led today's U.S. EVA-37, wrapping up his fifth career spacewalk and accruing a total of almost 32 hours in vacuum. Photo Credit: NASA

Jeff Williams led today’s U.S. EVA-37, wrapping up his fifth career spacewalk and accruing a total of almost 32 hours in vacuum. Photo Credit: NASA

With the primary objective of U.S. EVA-37 thus behind them, Williams and Rubins pressed on with their secondary tasks. Williams collected an Articulating Portable Foot Restraint (APFR), which he mounted onto the 57.7-foot-long (17.6-meter) Canadarm2 mechanical arm, deftly manipulated by Takuya Onishi. Meanwhile, Rubins returned to the airlock to collect Orbital Replacement Unit (ORU) bags, containing a replacement light for the Camera Group (CG)-9 location on the P-1 truss and the External High Definition Camera Assembly (EHDCA). After ingressing the APFR, Williams was moved to the P-1 worksite, where he made short work of removing an old, burned-out light and fitting and securing its replacement. Three hours into the EVA, a little after 11 a.m., the new light was in place and confirmed to be fully functional, as Williams successfully installed the EHDCA.

Controlled from the Mission Control Center (MCC) at the Johnson Space Center (JSC) in Houston, Texas, the EHDCA forms part of the ISS Communications and Tracking System and is designed “to provide an external high-definition video capability to view Earth and ISS.” Four locations at the Camera Port (CP)-3, 8, 9 and 13 sites on the ITS will provide a home for the modified Nikon D4 DSLR cameras, with 28-300 mm lenses. In addition to Earth observations, these cameras will provide high-definition imagery of visiting vehicles, specifically piloted Soyuz craft.

As Williams labored on replacing the CG-9 light and installing the EHDCA camera, Rubins returned along the port-side truss to the Solar Alpha Rotary Joint (SARJ). This is one of a pair of massive joints, each weighing around 2,500 pounds (1,130 kg), which rotate the space station’s port-side and starboard-side solar array groups to continuously track the Sun. Her primary task was to tighten three struts on the SARJ and perform a visual inspection, after which the spacewalkers wrapped up their work with a Multi-Layered Insulation (MLI) task and a check of the brakes on the Crew and Equipment Translation Aid (CETA) cart. Hopes to inspect and photograph the status of the Alpha Magnetic Spectrometer (AMS) were called off as the EVA closed in on the six-hour mark, and Williams and Rubins cleaned up their respective worksites and headed back to Quest.

U.S. EVA-37 ended at 2:41 p.m. EDT, after six hours and 48 minutes. This pushes Williams’ career total up to 31 hours and 54 minutes across five EVAs, making him the 43rd most experienced spacewalker in the world. In total, 216 men and women from Russia, the United States, France, Germany, Japan, Switzerland, Canada, Sweden, China, Italy, and the United Kingdom have performed spacewalks since Alexei Leonov’s pioneering excursion into vacuum, way back in March 1965. As for Rubins, she becomes only the seventh woman—after Kathy Thornton, Linda Godwin, Peggy Whitson, Heidemarie Stefanyshyn-Piper, Sunita Williams, and Tracy Caldwell-Dyson—to complete more than one EVA. As such, with a cumulative 12 hours and 45 minutes across her two EVAs from Expedition 48, she is now the world’s sixth most seasoned female spacewalker.

 

 

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33 comments to Expedition 48 Spacewalkers Restore Space Station Power Channel to Pre-2012 Configuration

  • TomDPerkins

    Hi Ben,

    Where did your post about the Ninth Falcon 9 of 2016 go?

  • Tom's drinking game

    It blew up….but it was not an explosion.

  • Ben Evans

    Hi Tom,

    Article was taken down shortly after the anomaly.

    Many thanks for your comment.

    Ben

    • Mark

      Why? If you are a legitimate news blog then you should report legitimate news. SpaceX explosion was news.

      • Nothing was removed about the explosion, we published a pre-flight report just AS it exploded, so it looked stupid on us to have a report up about a standard countdown test fire that was anything BUT standard.

        You imply we only publish “nice” crap, which shows how little you follow our reporting.

        Maybe you should see the article published today regarding the kaboom…

  • Tracy the Troll

    Ben,
    That was no anomaly as #9F9 was blown up by the Russians. They are really suffering from launch loss because of SpaceX and need more time to create a cheaper system in order to compete. This in addition to much lower revenue from their oil and gas exports makes them very a very dangerous player. I’m sure ULA, Boeing, Lockheed Martin, Blue Orgin etal are too unhappy that SpaceX has been slowed down.

    • Tom's drinking game

      Creating a cheaper system will just create more non-exploding fireballs. SpaceX has not been “slowed down”-
      that was just strike two and three is on the way. No mystery here, no conspiracy. Cheap blows up while expensive (ULA) does not.

      • Tracy the Troll

        Tom the Drinker,
        Especially when your competition does not know how to compete only collude, has no interest or desire to reduce launch costs because they are an industry legacy company/country who’s Motto is “What’s Good for Me is Good for the Country/Industry”…

        Now if I can just figure out how to convince the dinosaurs to stop blowing up SpaceX stuff long enough… They might just realize that cheaper launch will increase market size by increasing demand…

        • john hare

          Conspiracy theories are no more useful than ignorant theories from the other direction. Both are destructive to fact based discourse that just may be useful.

          • Joe

            “…fact based discourse that just may be useful.”

            Trouble with that is, at this point there are very few facts to discuss concerning the “anomaly” (except that the Falcon 9 blew up and the trouble appears to have begun at the second stage).

            Some folks do not want to wait.

            • Joe

              No really new information, but note the link below from GIZMODO (usually a very friendly site to SpaceX).

              Musk is saying it wasn’t an explosion just a “very fast fire”.

              Even most of the commenters aren’t buying it.

              It you are looking for a good laugh read through some of the comments.

              http://gizmodo.com/elon-musk-says-it-wasnt-an-explosion-that-took-out-spac-1786112682

              • john hare

                It may not have been a detonation, but it certainly fits the definition of explosion for many of us. A detonation of the entire propellant load available, well mixed, would have exceeded a kiloton in explosive power. That it was not a kiloton detonation doesn’t get him off the hook. The probability is good that an escape could have been made if the D2 capsule test mimicked actual conditions based on some people doing video matching of the two events.

                I think SpaceX will overcome this as well and continue to move forward after some amount of downtime. I do not think we can conclude deliberate, accidental, or negligent causes at this time, nor rule any of them out. It would be useful if most people would wait on some solid information if and when it becomes available.

                • Joe

                  Hi John,

                  “The probability is good that an escape could have been made if the D2 capsule test mimicked actual conditions based on some people doing video matching of the two events.”

                  Agreed, if an automatic abort was triggered; but that would require data systems to be monitoring for such an occurrence. We will still have to wait to find out what happened and if there were already sensors in place to monitor such a possibility. If not, even that would be a bit of a stretch.

                  “It would be useful if most people would wait on some solid information if and when it becomes available.”

                  Again agreed. I am not interested in “enjoying” a rockets failure (anybody’s rocket, even those whose fans seem to take such pleasure in other peoples problems).

                  My attempted point was Musk is doing himself no favors by trying to hand wave the problem away through semantics. Even some of his usual supporters were laughing, not a good thing for someone who depends a lot on a cult of personality.

                  • Chris

                    Joe,

                    Typical setup for fast detection would be break wires down the tank hooked to FPGAs. That can yield detection of fault in microseconds. A run of the mill FPGA running at 250Mhz is on a 4ns clock period. That is a lot of clock cycles to implement detection decision and action to trigger abort. We use these setup for fast failure detection in other industries as well (when software is too slow). Not sure about the latency on the engines and separation but for the pure circuit detection it could be done very quickly. Hopeful they have these sensors in place to get a validation test. Lemonade from lemons I guess…

                    • Joe

                      John,

                      Since there is no requirement for an abort capability, I would bet there is not such a set up for the current Falcon 9, but that is in the requirements for the crew rated Falcon 9.

                      A problem is how to avoid a false positive (an abort is a rather traumatic event and you really do not want an unneeded one).

                    • Joe

                      Chris,

                      Apologies. I answered with out reading the name of the poster.

                    • Chris

                      Joe,

                      Yes false positives would need to be carefully considered. Mostly through a safety not to arm until in critical period and the use of separate devices in a voting/quorum system. I could imagine bundles A/B/C system down the tank 120 degrees apart from each other. So at each 120 degrees you have 3 wires in the bundle on separate devices. If the A system says all were cut but not the B/C system that is very suspicious of a spurious event as they are right next to each other in a given bundle. All automatic abort designs will be a trade between false positives vs false negatives.

                    • Joe

                      Chris,

                      Absolutely.

                      Interesting thing is you are describing something very similar to what was being developed for the much hated (in the New Space Community) Ares I.

                      There were all kinds of complications (when are there not) concerning the need for extra lines, repeaters (due to the length of the required lines), available data channels, weight for all that extra hardware, etc.

                      The crew rated version of the Falcon 9 is going to be considerably more complex than the current version of the Falcon 9.

                • Tom's drinking game

                  “I think SpaceX will overcome this-”

                  I think the hobby rocket, which has now blown up twice, will never fly a human – NASA would be crazy to risk astronauts on such a vehicle after the the shuttle fatalities. The NewSpace flagship company is no longer in the human space flight business.

              • Mark

                I’m with you. 2 explosions at the upper stage LOX tank seem more than a coincides.
                I’m gonna renew my objection that this story was deleted from this site.

                • Joe

                  Hi Mark,

                  This site has been very fair in reporting on these issues and I would not jump to any conclusions.

                  Hopefully, they will soon have an article on the “anomaly” and continue with updates as the investigation continues.

                • John hare

                  IMO, the specific article had been overtaken by events, the event we have been discussing for a couple of days now. It was no longer relevant.

                • Mark conveniently ignored the regulars who DO follow our reporting…

              • James

                Joe –

                Thank you for the reference link to GIZMODO.

                Obviously, the International Space Station and future private space stations need highly reliable crew and cargo launchers. Hopefully SpaceX will eventually be able to provide such launcher reliability.

                However, I’m still a bit puzzled as to exactly why the then new and inexperienced company now known as SpaceX was initially chosen and funded by the US government to build the liquid propellant rapid response military launchers Falcon I, Falcon 9, and Falcon Heavy.

                For a Rapid Response Launcher consider the solid propellant Athena example compared to the Falcon launchers:

                “Athena Provides Unique Customer Benefits
                • 100% domestic content improves sustained availability
                • Inherent simplicity increases reliability
                • Responsiveness:
                – 99% probability of favorable winds aloft at launch vs 25% for liquid propulsion systems
                – Faster launch recycle time than liquid propulsion
                • Lowest Life Cycle Cost of all propulsion options
                – Long-term storage with minimal maintenance
                – Low ground support and equipment infrastructure requirements for maintenance and launch
                • Operational deployment demands
                – Easily maintained in a high state of readiness
                – Solid propulsion has decades of demonstrated 24/7 alert status capability

                From: http://www.lockheedmartin.com/content/dam/lockheed/data/space/documents/athena/Athena%20Fact%20Sheet%20Review%20vers%204.pdf

                Does the above noted solid propellant Athena “99% probability of favorable winds aloft at launch vs 25% for liquid propulsion systems”, along with additional undesirable Falcon 9 and Falcon Heavy launcher complexity issues, imply Falcon launch constraints that could add significant risks, delays, and real opportunity costs to launching both military and commercial payloads?

                Does the ability to launch heavy payloads to very high energy orbits only when the landing weather and wave height minimal conditions are met at the barge that would be the first stage’s landing site in such a situation also add another layer of undesirable launch constraints to Falcon 9 launches?

                Does having astronauts sit on an overly complex Falcon 9, or Falcon Heavy, launcher that needs to be quickly loaded with super chilled LOX and cooled kerosene propellants within the last half hour prior to launch meet the criteria of being an optimal risk minimized human launcher design?

                Do robust and simple operational launcher designs seem to be the most logical and lowest risk solution to government funded rapid response military launcher needs?

                Do the US government funded Falcon I, Falcon 9, and Falcon Heavy meet the criteria of robust and simple launcher designs or do they appear to be designs unable to meet the most basic criteria of rapid response military launchers and thus logically should not have had the long history of government funding they have received almost from the beginning of SpaceX’s formation?

                Why did our government repeatedly invest significant amounts of rapid response military launcher taxpayer money, and costly NASA rocket engine design and testing technology, in the operationally complex Falcon family of ‘not so rapid response’ military launchers designed by the new and inexperienced company that is now called SpaceX?

                Could a series of investigative history article here in AmericaSpace answer some or all of these questions?

                Do we Americans appreciate serious journalists who ask lots of hard and pointed questions to NASA, Congressional, and business leaders or do we mainly prefer writers who give us an endless flood of public relations pap?

                • Joe

                  James,

                  An interesting an thoughtful post.

                  However:

                  (1) I really have no inside knowledge of how SpaceX got into the government funding cycle.

                  (2) The debate on Liquids vs. Solids is one that has gone on for a long time, while I personally lean toward liquids (though not necessarily the Falcon 9 for numerous reasons) the arguments for solids should not be simply dismissed. Like most things in engineering there is not one right answer. Liquids are best for some functions, Solids for others.

                  • Tracy the Troll

                    Joe,
                    The real questions I have are for the Athena…
                    1. Can the booster with engine be reused with minimal cost?
                    2. Can the refurbishment process be automated?
                    3. Can the system be scaled up?
                    4. Can the system get to $100.00 per lb. to LEO?

                    Expendable is a word that the Space Industry needs to remove from their vocabulary. We can’t continue to allow a direct pollution event into the Ocean at every launch and think we really are an Intelligent Species.

                • Tracy the Troll

                  James,
                  These Questions are for you as you brought up the Athena Project…Any Input?

                  The real questions I have are for the Athena…
                  1. Can the booster with engine be reused with minimal cost?
                  2. Can the refurbishment process be automated?
                  3. Can the system be scaled up?
                  4. Can the system get to $100.00 per lb. to LEO?

                  Expendable is a word that the Space Industry needs to remove from their vocabulary. We can’t continue to allow a direct pollution event into the Ocean at every launch and think we really are an Intelligent Species.

                  • James

                    Tracy the Troll –

                    “The real questions I have are for the Athena…
                    1. Can the booster with engine be reused with minimal cost?”

                    Technically the first stage, and second, of the Athena is powered by a solid propellant motor.

                    The amazing Solid Rocket Boosters, SRBs, of the Space Shuttle were also solid propellant motors, and the casings and nozzle control equipment were recovered after parachuting into the ocean.

                    Unfortunately, reuse of the SRB casings, nozzles, and control equipment wasn’t an efficient cost reduction strategy, although they were regularly refurbished and reused for thirty years.

                    The SRB is a real world example of how rocket recovery and reuse isn’t always a guaranteed method of reducing costs.

                    However, the technology used in solid rocket motors is changing and new options for more economical refurbishment, and much lighter casings and higher Isp, seems to be quite doable.

                    Perhaps the real advantage currently of recovering first stages is the potential of closely inspecting a stage and gaining critical risk reduction information about possible design or manufacturing defects to help the first stage’s manufacturing company to remove those defects and improve the overall safety margins and reliability of its first stage product.

                    A long series of safe flights for a launch vehicle product can help to demonstrate minimized launch risks and thus payload insurance costs should be reduced for that particular launch vehicle.

                    A more reliable first stage, and thus a more reliable launcher, also implies the payload is more likely to launch on time.

                    A timely launch implies the payload/satellite will begin to make money doing communication work, reporting on weather/climate patterns, or whatever it is supposed to do exactly when it is supposed to be available to do that critical and valuable mission.

                    An overly complex or an unreliable launch vehicle runs the real risk of adding significant economic costs, or lost opportunities to make money or do other useful work, to spaceflights.

                    If the payload consists of humans in a spacecraft, a more reliable launch vehicle means it is less likely to need to make use of its somewhat risky emergency escape, or abort, system.

                    Abort procedures and systems do not come with a guarantee of a safe return to Earth and their use should be avoided if it is at all possible to do so.

                    If the equipment needed to allow a first stage to be recovered and perhaps reused adds significant mass, or weight, to that first stage, the recovery option takes away from the maximum payload to LEO capacity and/or flight safety margins from the launch vehicle and this reduction in margin may make the difference between a successful launch and a failure to place the payload in a useful or safe orbit.

                    So the safety or risk reduction trade-off may be for some launch vehicles between having more extremely valuable launcher margin during launch by having a less than maxed out launch vehicle that burns less propellant because it isn’t lifting the recovery/reuse equipment OR carrying the heavy equipment needed for reusing the first stage and using up more propellant to lift the heavy equipment that is needed for recovering the first stage and thus having less of a propellant margin for the first stage.

                    However, recovering the first stage makes it possible to inspect and make needed changes and improvements that could eventually reduce launch vehicle flight risks, and maybe costs, for future launches of that launch vehicle, but unfortunately may also significantly reduce the potentially mission critical risk reducing propellant margin for any given flight.

                    Remember that humans and the space missions they undertake are extremely valuable.

                    When astronauts die, or valuable payloads are destroyed, due to launch vehicle failure, the whole launch vehicle comes under close technical review and future flights of that launcher may be significantly delayed, or in fact permanently cancelled, due to the inherent spaceflight risks of that launch vehicle.

                    Cancelling a launch vehicle, such as the Space Shuttle System, is often incredibly costly in many ways.

                    Many payloads, and often the opportunity costs of a launch failure, have somewhat higher or much higher costs than the cost of the launch vehicle.

                    The most important cost issue isn’t the cost of the launch vehicle but is instead the cost of a launch failure.

                    If you are looking at the total launch vehicle costs picture over a long period of time, those costs are actually intertwined or dependent upon serious launch vehicle risk reduction efforts.

                    If a company, or nation, expects to have a commercially viable launch vehicle product, it should have various means to reduce, and keep on reducing, those launch vehicle flight risks to the lowest doable levels.

                    Neither recovery, and possible reuse, OR an expendable first stage is in and of itself a guarantee of a reliable, economical, and commercially useful launch vehicle.

                    Nonetheless, the option of sometimes recovering a vehicle’s first stages is potentially quite useful at reducing risks and therefore eventually costs even if that first stage is never reused.

                    • Tracy the Troll

                      James,
                      Thank You for that very detailed explanation…From your comments

                      “However, the technology used in solid rocket motors is changing and new options for more economical refurbishment, and much lighter casings and higher Isp, seems to be quite doable.”

                      “Perhaps the real advantage currently of recovering first stages is the potential of closely inspecting a stage and gaining critical risk reduction information about possible design or manufacturing defects to help the first stage’s manufacturing company to remove those defects and improve the overall safety margins and reliability of its first stage product.”

                      It would seem to me that SRBs do in fact offer an option for a quick turnaround and robotic refurbishment for consistent product production is there. I suppose the real question is..Will Lockheed Martin be the company to exploit this…I think not.

                  • James

                    Tracy the Troll –

                    “It would seem to me that SRBs do in fact offer an option for a quick turnaround and robotic refurbishment for consistent product production is there.”

                    I agree. Consider what Orbital ATK, the builder of the SRBs for the SLS, could possibly do:

                    “After combining the strengths above, Orbital ATK will feature three business segments.

                    Flight Systems will include space launch vehicles and spacecraft such as Antares and Cygnus, missile defense systems, and aerospace structures.

                    Space Systems will include commercial and government satellites, advanced space systems, and space components and services.

                    Defense Systems will include Tactical Missile Systems, armament systems, ammunition and energetics, and the like.

                    The three segments would have been responsible for 32%, 27%, and 41%, respectively, of the combined company’s $4.6 billion in revenue in 2014, according to estimates released by Orbital ATK.”

                    From: “Space News: Should SpaceX Fear the New Orbital ATK?
                    Orbital Sciences and Alliant Techsystems will merge into one company, Oribtal ATK, in February. Can it give SpaceX a run for its money?”
                    By Maxx Chatsko Feb 1, 2015
                    At: http://www.fool.com/investing/general/2015/02/01/space-news-should-spacex-fear-the-new-orbital-atk.aspx

                    ATK built and refurbished the Space Shuttle’s reusable SRBs.

                    Orbital ATK’s 30 years of valuable in-house experience with building and refurbishing very large solid rocket motors could be the basis of a new, reliable, large, and low cost launcher. Could such a new launcher’s first stage potentially be economically recovered and reused? Good question.

                    And:

                    “The three-stage rocket would be made of two solid-fueled lower stages, each made in-house by Orbital ATK, and a cryogenic third stage consuming liquid hydrogen and liquid oxygen. The engine for the third stage would be the BE-3U powerplant, a derivative of the engine Blue Origin currently flies on its New Shepard suborbital rocket.”

                    From: ‘Details of Orbital ATK’s proposed heavy launcher revealed’
                    By Stephen Clark May 27, 2016
                    At: http://spaceflightnow.com/2016/05/27/details-of-orbital-atks-proposed-heavy-launcher-revealed/

                    Orbital ATK currently provides supplies to the International Space Station with the Antares rocket and the Cygnus cargo spacecraft. And those useful vehicles could do the same supply hauling mission for any future private space stations or private modules that are attached to the International Space Station.

                    Another option could be an enlarged kerolox Antares core with two to four of the SRBs used with the SLS. Such a launcher might be an economical super heavy launcher with real recovery and reuse options.

                    Future upgraded versions of the Antares liquid propellant core and Cygnus spacecraft might someday be used to put cargo on the Moon, Mars, and Ceres.

                    Note that the reliable and economical Soyuz launcher first flew in 1966 and is still evolving and being used to lift satellites into LEO. It also launches versions of the human carrying Soyuz spacecraft, which first flew in 1967, and the robotic Progress cargo spacecraft that are headed to the International Space Station.

                    Reliable and economical products do tend to evolve and improve over time.

                    See: Soyuz (spacecraft) at: Wikipedia

                  • James

                    Tracy the Troll –

                    “A really stupid organization is one that ignores critical issues. Those organizations are not in business very long. A smarter, but still accident prone organization, addresses critical issues but improperly. A truly smart organization addresses all issues with the best possible judgement applied. A successful organization is very smart and always worried that something has been missed – or improperly evaluated. ‘Preoccupied with Failure’ is the term.

                    Or you can just remember to think ‘I’m not as smart as I think I am.’ Properly applied, that can work too.”

                    From: ‘Messy Accidents’ December 17, 2015 By Wayne Hale
                    At: https://waynehale.wordpress.com/

                    I like the simple idea of making sure you’re not setting anyone up for catastrophic failure.

                    Overly complex launchers, space systems, or missions that lack robust backup safety options and systems tend to to be excellent methods of committing astronauts to playing Russian Roulette.

    • Tracy the Troll

      Just so everybody is clear how much we pay the Russians for ISS human transport…

      http://www.businessinsider.com/space-travel-per-seat-cost-soyuz-2016-9

  • James

    Joe –

    “Liquids are best for some functions, Solids for others.”

    Yep.

    Thank you Joe and have a great week!