Time After Time: Imprints of the Space Transportation System Booster
- Thread starter Rocketdyne_J2
- Start date
I heard about this on Discord before, and I was looking forward to read this too. But now that I've read the Prologue, I'm absolutely excited to follow the thread as well
Prologue: "Tap-off"
It was the spring of 1981.
If that technology is being kept alive and even developed more, returning to the moon would be... I wouldn't call it trivial, but a whole lot easier as you have a proven technology that you know can lift the weights required.
I wonder what the Soviet answer will be... The same capabilities as the Shuttle will probably result in the same fear and a similar answer... But they are at a clear disadvantage if they can't reuse technologies from the N1 (because N1 couldn't be reused, because glushko would still cancel it) while the American can reuse SV technologies.
The margins for Skylab really aren't great; it reentered in July 1979 (assume this doesn't change for ITL). Columbia was delivered to KSC OTL in March 1979 with all the tile issues unsolved. As far as I know, the SSME development delays did not really influence that delivery date, and the SSME retesting of 1980 also fit within other delays the orbiter faced. So even if the SSME was the "long-lead item" OTL for STS-1 (and thus wouldn't be ITL), I can't see the tile problems being fixed and the Shuttle being stacked in five months.
Imo high thrust booster engines aren't the main technical challenge that Saturn-Shuttle averts for ITL SDHLVs; the OTL SRBs more than suffice for a SHLV, as SLS demonstrates. The real technical challenge of SDHLVs OTL is sidemount; you either had to contend with the limitations (size, mass, CG and stress, etc) of that setup, or radically redesign the ET-SRB stack to be inline (which means money) without making it incompatible with Shuttle ground equipment. The most valuable "technology" that ITL Saturn-Shuttle preserves is thus its inline configuration.
There's also the fact that SHLVs are just one part of a moon mission, and there are also mission profiles that rely on many launches of smaller LVs. However, that is an entirely different discussion, so I'll leave it at this.
All will be revealed in the next chapter.
I guess the Soviet engineers would have reacted with even more horror at Glushko's action ITL, if they're seeing the US reusing their moon rocket tech while their own space program doesn't.From a purely technical standpoint (barring Soviet interdepartmental politics), it is indeed interesting to think about the N1-derived possibilities of this timeline. From the top of my head:
- Using the same stages: orbiter inline on N1 (a la @nixonshead's), perhaps with a new upper stage and a reusable Block A
- Using just the engines: NK-33 powered boosters, RD-56/57 upper stage
Thanks for following!
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You probably know, Hendrickx’s Energia book mentions TsKBEM studying a reusable N1 Block A in 1974The margins for Skylab really aren't great; it reentered in July 1979 (assume this doesn't change for ITL). Columbia was delivered to KSC OTL in March 1979 with all the tile issues unsolved. As far as I know, the SSME development delays did not really influence that delivery date, and the SSME retesting of 1980 also fit within other delays the orbiter faced. So even if the SSME was the "long-lead item" for STS-1, I can't see the tile problems being fixed and the Shuttle being stacked in five months.
Imo high thrust booster engines aren't the main technical challenge that Saturn-Shuttle averts for ITL SDHLVs; the OTL SRBs more than suffice for a SHLV, as SLS demonstrates. The real technical challenge of SDHLVs OTL is sidemount; you either had to contend with the limitations (size, mass, CG and stress, etc) of that setup, or radically redesign the ET-SRB stack to be inline (which means money) without making it incompatible with Shuttle ground equipment. The most valuable "technology" that ITL Saturn-Shuttle preserves is thus its inline configuration.
There's also the fact that SHLVs are just one part of a moon mission, and there are also mission profiles that rely on many launches of smaller LVs. However, this is an entirely different discussion, so I'll leave it at this.
All will be revealed in the next chapter.
From a purely technical standpoint (barring Soviet interdepartmental politics), it is indeed interesting to think about the N1-derived possibilities of this timeline. From the top of my head:
- Using the same stages: orbiter inline on N1 (a la @nixonshead's), perhaps with a new upper stage and a reusable Block A
- Using just the engines: NK-33 powered boosters, RD-56/57 upper stage
Thanks for following!
He experimented in that time with really toxic rocke fuel Combination like
Pentaborane with Nitrogen tetroxide or Ammonia with fluorine,
last combination almost got used for high-performance upper stage on Proton rocket...
Act 1 Chapter 2: The Shuttle’s development and testing; a turning point for the Soviet space program
Chapter 2: “Earth, Wind, Water and Fire”
While Grumman and Boeing have had a fruitful working relationship during the Shuttle studies, a new round of contractor selections would be made for the final Space Shuttle. It would be a particularly intense race, for the impending retirement of other national launchers meant that only the winners got to stay in the space access market. Besides construction, the contractor would also be expected to take on the detailed design work, since NASA believed this opened up more innovation.The booster contractor selection was initially straightforward, with Boeing being awarded it. After all, Boeing was the only company that knew the ins and outs of making S-1Cs, and it was thus advantageous to have the same company handle its reusable version. Moreover, Boeing still retained all tooling for the stage, which was crucial for the S-1C’s development cost savings over other liquid booster options.
However, this also made for the most controversial contractor allocation in the STS program. The aforementioned monopoly Boeing had on the S-1C did not go unnoticed by the industry, and Lockheed Propulsion promptly protested to the General Accounting Office (GAO), suing NASA for choosing criteria that greatly favoured Boeing. Instead, Lockheed requested an open bidding, where all contractors’ abilities to contribute to the modifications are fairly evaluated, and the resulting winner be allowed to collaborate with Boeing (which would only provide the propulsive components) on the booster. Backed by McDonnell Douglas, Lockheed brought the case to court. [1]
NASA argued that splitting the contract would be counterintuitive, as putting two powerful companies on equal footing could impair effective collaboration, and likely neutralise cost savings gained from selecting an existing design. However, it was eventually ruled that the contract had to be changed. Drawing inspiration from the orbiter contract, Boeing was now required to involve other companies as subcontractors to a significant degree (the essential difference: Boeing would still be the only one to report to NASA and make major decisions). The most valuable subcontract, which was for the landing system and fins, would eventually go to Grumman.
The most significantly expendable portion of the STS, the twin external tanks (ETs), went to Martin Marietta of New Orleans. While the hardware was deceptively simple, this contract was particularly lucrative, as new tanks would constantly have to be built throughout the program. ET manufacturing would share the Michoud Assembly Facility with booster overhaul and manufacturing, so that some manpower and facility costs are amortised. Different sections of the vast factory would be dedicated to their respective hardware, effectively making Michoud the centre of all heavy rocketry in the US.
Finally, there was much deliberation over who developed the orbiter. As with the booster, the prime contractor would only perform integration, while distributing component work to other companies. Four companies: North American Rockwell, Grumman Aerospace, McDonnell Douglas and Lockheed, submitted bids for the contract to rule all contracts.
Lockheed was the first to be eliminated, having scored the lowest due to the inconsistent technical depth of its proposals. McDonnell Douglas was done in by its elaborate and questionable plan to spread work between different company centres. NAR and Grumman received similarly excellent scores. Eventually, NAR's demonstrated expertise in previous aerospace projects, management methods, and low bid gave it an edge over Grumman's stunning technical thoroughness. With this last contract being signed on September 18 1972, the Shuttle program began in earnest.
The Shuttle program was to go from paper to practise in four increments: Increment 1 was detailed design, to be carried out by the contractors. Increment 2 was Design, Development, Testing and Evaluation (DDT&E), a cycle in which experimental results cyclically feed into adjustments of the product and vice versa. Increments 3 and 4 would involve actual flights: first the construction of two evaluation orbiters to carry out test flights, followed by the addition of more orbiters to build up an operational fleet size as Shuttle matures into Increment 4.
The booster was comparatively further along in these stages, although much work still had to be done to make an expendable stage capable of regular ocean recovery and reuse. As development progressed, the S-1C became the S-1D in NASA and Boeing documentation, to be numbered with 600-series serial numbers. In keeping with the BSBO proposal, the S-1D would reenter nose-first. The LOX tank forward dome would take the heat and provide a blunt aerodynamic shape for maximum drag; upon splashdown, it would also have to withstand tons of water crashing against its gores. Hence, the S-1D would receive thicker tank walls, and jettison its forward skirt and the interstage on each flight. All of the hardware previously located in those parts would be moved into the intertank.
Then there were the fins. During ascent, the Shuttle's massive wings generated forces that would flip the stack around. To counter this unsatisfactory tendency, the Saturn's tiny fins ballooned to massive airfoils that stretched up to the intertank, and tripled the stage's diameter (contrary to popular belief, drag forces defined their size, as the shock waves the ETs generated disrupted most of the laminar airflow needed for lift). With the risk of striking the launch tower increased as a result, a more vigorous avoidance manoeuvre would be implemented. This, along with control authority, was aided by increasing the F-1 engines' gimbal ranges by 2°.
Problems that previously hid in the details were also now rooted out. Such a change befell the Orbiter's vertical stabiliser; it was found that a single central fin risked impact with the S-1D as it swung out of the way. Thus, the fin was split into two smaller ones on the wingtips; this configuration also allowed the orbiter to fit through the VAB high bay doors.
Any vehicular abort system was also deleted once and for all. While both the BSBO and TAOS included small solid motors beneath the OMS pods, they couldn't make an orbiter escape the failure of its own propulsion system, which made them too ineffective for their mass penalty. Thus, they were deleted before the Shuttle program even started. Now, an ejectable cabin was considered, but this would too entail mass, and introduce shock-sensitive ordnance too close to the cockpit for comfort. Scenarios such as the crew surviving a crash landing only to succumb to abort propellant ignition was unthinkable. It was thus decided that the only end to abort system woes was to make the Shuttle so reliable that it didn't need one. Most of this job was already considered accomplished through Apollo-Saturn flight heritage, however.
All of this and more was determined in simulations and analysis before any hardware was built. The Shuttle used software simulations, a first in aerospace history. However, traditional scaled testing still found its place in many other parts of the program, including the early stages of booster development that started in early 1974.
First were complete tests of the improved F-1A engine, a continuation of development that was almost curtailed after Apollo. An upgraded version of the F-1 that took humans to the Moon, this version promised more thrust, higher efficiency, and most importantly throttle capability. The extra thrust would allow a Shuttle to continue ascending even if it lost an engine immediately after launch, while the ability to go as low as 70% of its rated 8000kN of thrust made the Shuttle a gentle beast; future astronauts would sustain no more than 3g during launch. However, the case of losing two engines within 18 seconds after liftoff was an abort ‘black zone’ - in which there are no options to save the crew; due to the demonstrated reliability of the F-1 series, this was deemed acceptable due to its remote likelihood.
Undertaken in parallel to the booster engine tests were a series of quarter-scale stage drop tests at the Dryden Flight Research Center: a miniaturised S-1D was released from a NB-52 platform, after which it descended from stratospheric altitudes on a system of similarly scaled down drag flaps and chutes. The massive fins, which were sized to counteract the orbiter's aerodynamic forces during ascent, were more than enough to keep the model pointed nose down throughout the descent, until the model ploughed headfirst into the sand. However, the ease of subscale tests was a false reassurance. Designing the real descent system would prove to be arduous in practice, with the flotation bags and structural changes to support parachute stresses often being reasons for missed schedules and budget caps.
This underestimation of the descent was offset by excess caution in making the S-1D seaworthy. Due to assumptions that salt water immersion would pose the most problems, the Stage Oceangoing Recovery Tests (SORT) were the first full-scale operations in the Shuttle program. The project would involve taking a full-sized stage out to the ocean for the time it would take to get it back on real missions. It took off in June 1974, soon after the dimensions of the S-1D were finalised. Everything SORT used was borrowed; as no S-1Ds were built yet, the test subject was S-1C-515, a leftover stage from the Apollo program. With its forward skirt removed, simulated fins and airbags added, it set off for a trip around the Cape in the belly of Casa Grande-class LSD-17 Catamount, a Navy dock landing ship with a large, floodable aft bay. The ageing vessel was transferred from the Navy to NASA, which then chopped off parts of its rear decks to provide clearance for the booster’s fins. A convoy of tugs and support ships followed to assist the simulated recovery, as well as manage any contingency that could arise.
USS Catamount underway during her Navy service.
Two Monitor boats enter the bay that will hold S-1Ds in the future.
Shortly after departure, Catamount’s well deck was allowed to flood; the aft doors were opened, and S-1C-515 slid into the ocean. The ‘lower’ (relative to the water) fins were then dumped separately into the water, as they would be recovered separately on a real flight. The pre-inflated airbags did their job, and held the prototype F-1A engines up. Under supervision and measurement, the parts bobbed around for the half-hour recovery vessels were expected to need to get to a real booster, before boats began swarming upon the stage to get it back into Catamount. Sea swells made S-1C-515 chip the ship's hull several times, though the damage was mostly cosmetic. After an arduous operation, S-1C-515 and its fins were safely back where they started; water was drained from the well deck, and the stage was selectively pressure washed with freshwater (the unwashed portions would serve as a control for salt water damage). Catamount then sailed for 600 km in the open seas near Florida to simulate the time it took to get back on a real mission.
Afterwards, the stage was taken to Michoud, and partially disassembled for analysis and cursory restoration; it was then put back together, and sent to the National Space Technology Laboratories (NSTL) for a hotfire test. To everyone’s relief, the engines started without issue and ran for a planned 20 seconds; a full duration burn was carried out a few days later. The refurbishment needed between firings was also less extensive than previously thought; the process mostly consisted of decoking the engines using solvents. Conversely, the recovery procedures left much to be desired and refined, but the booster’s head start gave everyone plenty of time to do that. The tests also proved the modified Catamount a capable recovery vessel, so it would be retained for the early flight program. The SORT tests would later be repeated with test articles more representative of the S-1D between 1977 and 1978.
The orbiter engines, the J-2S, were also put through their paces at the NSTL in parallel to the F-1A. The J-2S engine deviated far more from its ancestor than the F-1A did; for simplicity, its gas generator cycle was replaced by the tap-off cycle, where the turbine would be driven from gases taken directly from the main combustion chamber, instead of a separate gas generator. Starting the engine’s turbopumps was now also done using single use solid-fuelled cartridges. While most development work was done before the Shuttle program, and J-2S engines have been tested as single units even before Apollo ended, they were yet to be tested as part of the orbiter’s propulsion system. That changed in late 1976, when MPTA-098 first roared to life. The Main Propulsion Test Article was an exact recreation of the orbiter’s thrust structure, but had nothing else; a single rectangular truss poked upwards, shouldering the first pair of external tanks that came off Martin’s new production line at Michoud. MPTA-098 would make a dozen test firings of the full cluster, up until the end of 1979.
A full orbiter test article was also built; this was the Structural Test Article, STA-099. Identical to the production orbiters’ metal structures, STA-099 would undergo countless non-destructive evaluations to ensure that all parts could withstand design forces, with added margins. However, it lacked many of the systems needed in a real orbiter, for it was destined to never fly. Its future lay in a storage hangar, waiting to be resuscitated if its flying siblings ever needed proof that planned structural modifications were sound, or just to be scoured for spare parts.
The honour to fly first lay with OV-101 Constitution, rolled out in September 1976 on Constitution Day.
¶
When what would become OV-101 was laid down in 1974, few expected the most trivial part of the process to become one of the most publicly convoluted within the fleet: naming it.
Beginning in 1976, governmental offices received a deluge of letters from "one of the most dedicated constituencies in America" - Star Trek fans. Their lone request was for NASA to name the first Shuttle Enterprise, after the starring spaceship in the TV series. Despite attempts to lean into its nationally significant meanings, it was ultimately foregone to avoid looking as if the government appealed to a TV fad. However, Enterprise was a good name, and so was the publicity value of satisfying a group interested in space; thus, it was deferred to the next orbiter, OV-102. [2]
Constitution made its way to Dryden via road, where it began the first of its tests in 1977. After verifying taxi capabilities, it was mated via attachments within the landing gear wells to the 747-converted Shuttle Carrier Aircraft for Approach and Landing Tests (ALT). Through a five-flight program involving astronauts Fred Haise, Gordon Fullerton, Joe Engle and Richard Truly piloting Constitution, practical aerodynamic data about the Shuttle's final approach was obtained. This was followed by ferry flight tests, to demonstrate the Shuttle’s ability to be carried on top of the SCA, as it would need to be throughout the program.
The combined results from Constitution’s ALTs and STA-099’s stress tests led to structural changes as margins were reassessed. The list of modifications piled up, and soon significant parts of Constitution would have to be rebuilt for its prospective first flight in 1979. Costs of the modification were also a concern when budget margins were eaten up by technical difficulties, with parts ranging from APUs to computers driving program costs beyond the initial estimate. With the less complete but otherwise immaculate STA-099 lying around, the decision was made to relegate OV-101 to the ground, and modify STA-099 for spaceflight. OV-102, which was undergoing final assembly at the time of the decision, would fly in Constitution’s place.
1977 was also a landmark year for other parts of STS. That September, the first true S-1D rolled out of the Michoud Assembly Plant to great fanfare: S-1D-BTA (for Booster Test Article, nicknamed ‘Battleship’ like the Saturn test stages). After its test firings at NSTL, with a full set of F-1As producing an earth-shattering 4 MN of force, it was sent to join Constitution and the ET-MPTAs for launch vibration tests at Marshall Space Center. There, the first full, albeit inert Shuttle stack came into being, and it was used to troubleshoot various structural problems that only arose in practice.
1978 had none of the spectacular ALT flights, but testing and construction were nevertheless going into full swing for the first spaceflight of the Shuttle.
¶
From its inception, NASA replicated the military's approach of block testing. This involved repeatedly checking that lower-level components worked perfectly, before live higher-level components were ever coupled into the system. However, the Saturn V had proven the feasibility and time (thus cost) - effectiveness of all-up testing; with this approach, all hardware would be rigorously checked out on the ground, before being all put together for one seminal flight test. The reasoning goes that if the last component functioned perfectly, one might as well add the next, and so on, leading to a reduction in the number of test flights.
For the Shuttle, this philosophy extended to the crew. Besides eliminating a costly automatic system that would only be used a few times, planners also reasoned that humans could manipulate the vehicle in more ways during contingency situations, increasing the chance of mission success. However, putting humans aboard the first flight also greatly elevated the stakes of failure; without an abort system besides ejection seats, calling the Shuttle's first mission the ultimate test flight would be an understatement. Care was thus taken at every step to minimise the risk for the first mission, although it only went as far as the things people knew to care about, and could reasonably care about within cost-benefit compromises.
After completing testing, S-1D-601 and ETs 1, 2 were shipped via Apollo-era barges from Michoud with few issues, and were placed into storage in the VAB high and low bays respectively. They would await Enterprise’s arrival in early 1979, for the inaugural mission of the STS program in September 1980. Everything was going well, and for a moment, all the action seemed to fit precisely into making STS-1 go off without a hitch.
With the Shuttle's service on the horizon, new imagination and existing implementation prepared to make use of its capabilities. In January 1979, ground was broken to convert the old Manned Orbiting Laboratory launch site (SLC-6) on the US West Coast, in Vandenberg Air Force Base near Point Arguello. Military payloads that needed to cover the whole globe required a polar orbit, forcing the Shuttle to launch due south. This was something it couldn’t do from Cape Kennedy without dropping parts on habitable areas; the Pacific waters due south of SLC-6 solved this problem. The modifications were extensive, for Titan 3C facilities now had to accommodate what was effectively a Saturn V. Operations from there were expected to commence in the mid-1980s.
Other plans concerned existing assets, some like Skylab already in space. Mothballed since its last crew left in early 1974, planners hoped to resuscitate the country’s first space station for a new era. With its orbit decaying due to latent atmospheric pressure at thermosphere altitudes, an early Shuttle mission would send an unmanned space tug (not to be confused with the Integrated Program Plan concepts) to reboost Skylab to a safer altitude. Saving Skylab would give NASA a space station from the get-go; later missions could restore Skylab’s depleted resources and damaged systems, and even expand it with new modules to give it new capabilities. Elaborate considerations were made to safely work the unmanned space tug into the risky first flights, upgrade the probe-and-drogue docking system to the APAS androgynous port developed for Apollo-Soyuz, or refill tanks that were never designed to be accessed after closeout.
Alas, those schedules went to hell when SCA 905 landed with an unfinished Enterprise fresh out of final assembly. OV-102 was covered with placeholder tiles, as work could not be completed at Palmdale in time. Worst of all, it had exposed aluminium; many tiles had fallen off during the ferry flight, a harbinger of problems to be revealed. The scarred orbiter was rolled into the newly built Orbiter Processing Facility (OPF), where Rockwell expected to finish adding the last of the tiles.
But it was there that the problems were revealed to be much worse. To save development costs, Shuttle management employed a priority-based approach of solving engineering challenges, where more resources and time would be diverted to the systems expected to cause the biggest headaches, and less towards the others. While this made sense on paper, this assumed that the initial expectations lined up with reality; the tile analysis was dead wrong, as the adhesives holding them in place would actually need to be much stronger than expected.
The result was overtime work to reattach every tile on-site. Interns were brought in to apply the 30,000-odd ceramic squares to Enterprise, and test their strength with special suction cup rigs. But then Rockwell determined that tiles in some places needed to be denser to withstand more aerodynamic and heat loads; caution caused this number to balloon to all of the tiles, before prudence held sway and lowered the number to 4700. This was fortunate, as the touch-up work was anything but straightforward; the technicians were literally set two tiles back for every three that went on.
Instances of tasks taking longer than planned to accomplish popped up in similar fashion across the program. The delays were not attributable to a lack of technical and managerial acumen; rather, the timelines were set over-optimistically. Thus, Enterprise’s schedule slide was something that erecting S-1D-601 and attaching its fins early couldn’t change. Over time, some potential commercial customers elected to switch their satellites to ride on the last Deltas, while Skylab burned up in July 1979, earlier than expected due to increased solar activity. And the upgrades didn’t stop; time allowed more problems to be identified, which meant fixes to be carried out in tandem with the cautiously dicey (sometimes literally, to prevent breakage from reentry thermal expansion) things done to the tiles.
But work still progressed, albeit very slowly. There were also benefits to the delay: it gave more time for STS-1’s crew to train, both for the expected and contingent. Enterprise would fly with just two crewmembers for the inaugural flight: moonwalker John Young in command, and MOL astronaut corps candidate Robert Crippen as the pilot. As with Apollo, a full backup crew was also appointed.
While the mission they were training for was dangerous, Young was thankful that it hadn’t been planned to be even more so. Early in the planning process, some proposals did not plan for STS-1 to reach orbit. Instead, it would be a crewed abort test, with the astronauts flying one of the three most difficult abort modes. This idea was soon shot down due to its incredible and unjustifiable risk, with Young’s criticism playing a significant role.
More contingency plans and tools were also devised in the interim. In light of the newfound tile issues, McDonnell Douglas was awarded a contract in January 1980 to create a tile repair kit. This system would involve a cure-in-place silicone filler that can be injected using a caulking gun, to fill voids left behind by missing tiles. Blocks of pre-cured silicone were also available for more extensive damage. The tile repair kit would be operated by a spacewalking astronaut, whose reach is extended using the upcoming Manned Manoeuvring Unit (MMU) jetpack. Despite its apparent importance, there were worries that repair efforts would result in more damage. And as the schedule would have it, the kit would not be ready for STS-1.
OV-102 was finally mated with the ETs and rolled out of the OPF in March 1981, to be united with the booster. Staff in the VAB gingerly operated cranes to bring the parts together within the building’s vast confines. With all parts joined, secured and checked over the course of a week, ML-2 and the complete stack were loaded onto one of the Mobile Transporters, to make the crawl to LC-39A.
For the first time in six years, the Shuttle’s time to fly finally seemed within reach. To most within the country and some abroad, it was great cause for anticipation and excitement, as manned spaceflight was getting back on its feet. However, for some who had little reason to care about American philosophising on the wonders that STS-1 meant, it was a longstanding fear bearing fruit.
¶
While bilateral relations between the US and USSR have been gradually warming throughout the Nixon presidency, it did not diminish a wariness of one another's military strengths and developments.
Yet, despite the knowledge of the Shuttle program as early as 1972, and tentative suggestions that it held yet-unknown military potential, many in the USSR had other assessments about the nature of the Shuttle. The engineers determined that the Shuttle was neither an efficient way of getting cargo to orbit, nor would it offer as many immediate military advantages as initially believed. However, they had their own reasons to carry on, for spaceplanes and reusability have also been a persistent dream of those on the eastern side of the Iron Curtain. Projects such as the MiG-105 “Spiral” that bubbled in the background of the now-concluded Moon race were stillborn attempts to conceive such a thing. And like the Americans after Apollo, the Soviet engineers haven't seen budget pastures since Khrushchev (and his eye for space spectaculars) was ousted from power.
The Soviet manned space program was also reeling from the consecutive failures of N1-L3 moon rockets and two Dolgovremennaya Orbitalnaya Stanziya (DOS) stations, the Soyuz 11 disaster, and reorganising in the aftermath of a massive restructuring: 1974 saw all the former bureaus consolidated under one organisation called NPO Energia, headed by “general designer” Valentin Glushko, formerly chief designer of OKB-456.
At this point in time, the N1 moon rocket was still kicking, with vehicle 8L being prepared for the saving grace of success. The N1 was either a rough gem or a white elephant, depending on who one asked. Some even thought of integrating it into the spaceplane just as the Americans have done with the Saturn V, or using it as the foundation of a more comprehensively planned long-term moon program; in view of the 6 billion rubles already spent, it seemed like madness to abandon it.
Yet that was exactly what Valentin Glushko did upon his appointment as General Designer. Despite valiant efforts at opposition, the “unanimous” consent of powerful ministers decisively ended the N1; in related industrial centres around the Soviet Union, all activity gradually crashed to a halt, and many feared that the finely balanced bureaucratic machines wouldn't be easy to restart.
At Glushko's recommendations, chief designers were allotted to each of the remaining main projects: a new multipurpose heavy lifter, the Mnogorazovaya Kosmicheskaya Sistema (MKS, lit. “Reusable Space System”) spaceplanes, space stations, the Apollo-Soyuz Test Project, and a tentative moon mission. But Glushko probably dreaded managing these yarn balls of old projects that continued rolling under their own inertia; for a new start, he wanted something that was truly his own. And so on August 13, 1974, Glushko presented his vision for space exploration during a conference of all managers, which was organised by higher authorities to "probe" the general mood. He proposed a series of modular launch vehicles with payloads ranging from 30 to 250t to LEO, using common components. This system was called the Raketnyy Letatelnyy Apparat (RLA, lit. “rocket flying apparatus"), and he proposed a staged implementation spanning the next decade, which would require 12 billion rubles. As for the MKS, it could be accommodated on the 135-ton payload variant (RLA-135), as a medium-sized glider "built by someone else".
The ire was immediate. For a start, the RLA utilised staged combustion kerolox engines, which Glushko had vehemently opposed throughout the N1 program; his explanations that stage combustion was too immature for kerolox before the late 60s could not quell suspicions of conspiracy. Next was Glushko's unwillingness to accommodate other new differences. The RLA's upper stage used the exotic, artificial Syntin, as he dismissed hydrogen the same way he once did kerolox staged combustion. Then there were worries that Glushko's plans repeated old mistakes with the N1: the RLA echoed the N1's pitfall of not being designed from the payload down. Finally, building a heavy lifter from scratch meant that the country would not have one until the next decade, at the soonest. They would also needlessly spend resources the Americans had saved by reusing parts of their Moon rocket.
But heavy-lift capability was something neither the N1 could concretely promise, with four failed launches under its belt and only the creators’ word to take for a successful fifth. The N1's large monolithic structures were also a poor fit for a sustainable Soviet space program. Thus, Glushko used these decisive facts against supporters of the N1 like Vladimir Barmin. The ministers were also convinced that these issues would not disappear simply by subsuming the N1 into the spaceplane.
While the meeting did not cement support for the RLA, the concept’s modular design would be very similar to later launch vehicle designs. This was attributable to the limitations and techniques shared by all who worked in the Soviet space program; modularity was gaining recognition as the solution for logistics and operational headaches.
Eventually, the decision of what launch vehicles to develop was deferred to circumstance; what space endeavours the country would begin in the next five years would dictate the means of space access and payload capacities required.
One (very expensive) path was to upstage the American “Flags and Footprints” moon landings with a permanent lunar human presence. Barmin, whom Glushko alienated in that meeting, was ironically deep into planning a Moon base (“Barmingrad”) similar to what Glushko wanted (“Zvezda''). Animosity resulting from the meeting separated the Moon base efforts within NPO Energia, further hastening its removal from the list of potential space endeavours. As for space access, capsules to replace the Soyuz were a strong contender against the MKS. Such options included the Zarya-2, involving an upsized Soyuz return module that would land on rockets at the end of a mission, and the VA, which would be paired with the space station-sized Functional Cargo Block (FGB) to form the TKS spacecraft. But none of this was to be.
In 1974, the news of the Vandenberg launch site allowed the Shuttle's incomprehensible combination of questionable reuse economies, payload bay size, and high cross range to click. With a 15 x 60 foot cargo bay and 2000 km of crossrange capability, the Shuttle could launch from Vandenberg over the poles, pretend to pass harmlessly overhead, before suddenly bending around using aerodynamic lift and dropping a thermonuclear warhead onto Moscow. That same crossrange could also counter the landing site’s displacement due Earth’s natural rotation, allowing the bomber crew to return home on the same orbit. This chain of revelation rose through the ranks of the Soviet military-industrial complex. In the interest of caution, the USSR would have to match this rival technology as soon as possible. Thus, the Politburo ordered that something similar be built.
The sudden commitment was met with disagreement, leading to serious confusion within the leadership. Furious at this state of affairs, Defence Minister Ustinov personally intervened; he asked for a summary of the current status, purposes and potential designs of the MKS program. Glushko complied, and sent acting deputy Valeri Burdakov in person a few days later, carrying a confidential notebook. Deciding what to put into that notebook had brought influential camps within NPO Energia to figurative blows; only one design should be submitted for a Technical Reference, but there were three competing visions for what the MKS should now be.
Initially, aware that the Americans had arrived at their design through prolonged and detailed iteration, designers decided to use the American design as the basis for the MKS. This concept was named the OS-120, and featured a similar orbiter, but with the S-1C replaced by a new 8m diameter kerolox stage or the N1's first two stages (despite its cancellation, some designers still held out to this point). OS-120’s most notable difference from the Shuttle was its abort system: the crew compartment could be blasted away from the rest of the stack by powerful solid motors. However, this design was extremely unworkable; the OS-120 orbiter was heavier than the US Shuttle due to limitations in manufacturing techniques. The need to recover engines only added to the woes, while the overwing external tank position also severely limited fuel capacity growth. The S-1C analogue was also ill-suited for transport, as those who worked with the N1 knew all too well with wide stages. While the OS-120 would be further modified to suit Soviet sensibilities, the MKS designs soon split into another philosophical bloc.
Said alternative was the MTK-VP, effectively an orbiter with neither wings nor integrated launch engines. Instead, the MTK-VP would descend under parachutes and land lengthwise on skis; it would be boosted to orbit using an independent heavy-lift launcher. Glushko approved of the reasoning behind chopping off the massive wings, which only added dead weight and aerodynamic headaches. It was also here that he saw an opportunity to preserve his RLA; developing it now for the MTK-VP would easily enable the construction of a lunar base in the future, fulfilling two expensive dreams sequentially using one limited budget. However, the MTK-VP had one shortcoming: it lacked the American Shuttle’s crossrange.
Generated during the deadlock between OS-120 and the MTK-VP was another idea, the Orbitalny Korabl-92 (OK-92, for 92 tons of dry mass), specifically drawn up by Sadovskiy’s 80-man team to placate both sides. The OK-92 orbiter would resemble the OS-120 in capabilities, retaining its massive wings for crossrange. However, the Americans' integrated final stage was offloaded to a separate, expendable hydrolox stage powered by RD-57 engines (already under development for improved N1 variants) from Arkhip Lyulka's design bureau. This combination would ride on a booster stage made of clustered common cores, which resembled Glushko's RLA and was even slated to use the type of engines he outlined.
The prospect of building something resembling the RLA-135 should have made Glushko a fast supporter; yet the general designer vehemently opposed it. He criticised the use of liquid hydrogen in its upper stage, seeing it as a technology whose time has not yet come. Deciding to focus on the MKS would also doom his moon base plans.
However, his stance eventually abated for the want of bureaucratic pressure. And regardless how the upper stages eventually panned out, the OK-92 would provide the opportunity to build the engine of his dreams, to crown his career as the premier rocket engine designer. The launcher could also be readily converted for lunar missions. Thus, on January 9 1976, Glushko somewhat reluctantly signed for OK-92, clearing its draft to Ustinov’s desk. Shortly thereafter, Decree 132-51 officially authorised development and construction of the MKS. However, these did not mean a de facto consensus; discussions continued well into the end of 1976, when an interdepartmental commission chaired by chief designer of TsNIIMash, Yuri Mozzhorin, formally decided upon basing the MKS on the OK-92.
For the rest of the year, amendments were made to the configuration to suit operational constraints. These included shrinking the upper stage for ease of transportation, replacing the hypergolic orbital manoeuvring system (DOM) with a LOX/Syntin one, and making the OK-92’s wings foldable like the Spiral’s to eliminate severe bending moments during launch. A debate also raged over what aerodynamic shape the shuttle should adopt: former Spiral engineers pointed to hard-earned practical experience with the blended body shape, while NPO Energia proposed that following the American Shuttle’s form would save development time by using what the Americans proved. In the end, the matter was deferred to the Ministry of Aviation Industry (MAP) minister, who deferred it to Glushko, who then deferred it to the Council of Chief designers, where a simple majority selected the American Shuttle’s form.
On November 21 1977, the MKS’ final configuration was cleared for detailed design by engineers in the MAP. To design the MKS, efforts from three design bureaus were consolidated into a new enterprise, NPO Molniya (“Lightning” Research and Industrial Corporation). A Tushinsky factory became its base of operations; a place where Yak warplanes and trolleybuses were built now played host to the best spaceplane expertise in the Soviet Union, with experts such as Gleb Lozinski having participated in the old Spiral program, and workers from industry giants like Myasishchev’s bureau. It was also at this point that a proper name solidified for the MKS: Buran, after a vicious winter wind that causes blizzards in the steppes. The name was probably reused by Myasishchev, whose bureau had worked on an identically named cruise missile before Sputnik was even launched.
As the Buran underwent refinements, Soviet intelligence watched the American Shuttle effort closely. They were somewhat surprised that few demanding test flights were carried out; it was an inexplicable departure from an approach that gave them success in Apollo. But the Soviet engineers were not about to take such chances, and planned out an incremental series of flight experiments that would prove the design's space-worthiness.
Subscale test models, named Bespilotnyi Orbital'nyi Raketoplan (BOR, lit. “Unpiloted Orbital Rocketplane”), would be built. The first example based on Buran’s shape was named BOR-5, a continuation of numbers used in the Spiral program. The ⅛-th scale models would sustain ground-based structural, acoustic and thermal tests, while some would be launched on suborbital trajectories by Kosmos rockets for reentry tests. This would be followed by an airworthy full-size vehicle, flown using jet power from engines that would also be present on the actual Buran.
Development also began on the country's most advanced autopilot to date, for it was decided early on that Buran would not fly crew on its first flight. Thus, the reentry and landing, which were reportedly hand-flown in the Shuttle, were neither manageable with inflexible electromechanical systems, nor had the luxury of human adaptability. Another digital computer (and the appropriate algorithms), like the recently operational one for rendezvous, would have to be developed.
Work on the launch vehicle, the 11K25, began in earnest at NPO Energia. Propulsion subdivisions got to work realising a downscaled version of the engine outlined for the RLA, a kerolox staged combustion engine based on knowledge gathered from the RD-150 program; the intervening years saw its thrust specifications more than halved. Even then, it was expected that this engine, the soon to be RD-170, will remain the most difficult part to develop.
Separate decrees realised more parts of Glushko's vision for the RLA. Back in March 1976, the 11K77, an equivalent smaller cousin to the 11K25's RLA-135, was approved. It would be based on one of the modular first stage blocks, with a smaller upper stage powered by RD-57s. Incorporating RD-57s in the 11K77’s upper stage would give the engines valuable flight heritage before the larger vehicle ever flew. While Glushko imagined something similar being a vital proving ground for the larger vehicles, the 11K25 would soon inflict sufficiently different demands on the booster to make that difficult. However, some commonality was eventually retained, mainly by directing booster axial loads through the 11K25 interstage instead of the core block.
Despite all the activity, there was much criticism against allowing Buran to dominate the USSR’s space program. Many still questioned the sense behind it, and had good justifications to back their reasoning on. One of these people was former cruise missile builder Vladimir Chelomei, head of TsKBM (originally OKB-52). Believing that the country could not support Buran and make use of its capabilities, he proposed the smaller, cheaper Logkiy Kosmicheskiy Samolot (LKS, lit. “Light Cosmic Plane”) back in 1975. This 20t two-seater could carry 4t of payload in its cargo bay, and be comfortably launched on his bureau’s Proton rocket. But even as ministers decided to proceed with a Shuttle analogue, and subsumed his resources into Buran, Chelomei continued his silent rebellion. By 1979, Chelomei’s bureau would secretly produce 40 volumes of technical details and a full-scale mockup, all to go nowhere.
But Chelomei, himself a proponent of modularity, agreed with the ideas behind the 11K25. Believing and hoping that this launcher held more promise, work started in his bureau to develop a space station that made full use of its capabilities. The old Almazes and DOSes, while capable, were rapidly running out of potential. Chelomei’s design thus called for two DOSes to be joined back to back, forming a large core module. The resulting module, called the Yadro Modulnoy Orbitalnoy Stantsii (YMOS, lit "Modular Orbital Station Core"), wasn’t the end; it was merely the core component for a modular station that would incorporate two of them, along with other DOS and FGB-derived modules. [3] Chelomei's bureau intended for the YMOS to inherit the space station effort, which had the additional advantage of making opponents of Buran think twice before leaving the YMOS without a launch vehicle. It was also promoted to leadership as a candidate test payload for the launch vehicle, although something less costly would eventually be selected for this role instead.
Glushko backed Chelomei’s new station module; he realised that with another future payload of national importance, the 11K25 would have a reason to be designed as a multipurpose heavy lifter in line with his RLA vision, instead of around the Buran. His support coincided with the space station emerging as an equal (and perhaps more important) national priority with a February 1976 decree, due to a desire to not fall back from their hard-earned specialty of space stations, as the US did from the Moon. In other words, keeping space station activity consistent and evolutionary, and selling it as a more “practical” way of using space, would more than make up for the N1-L3’s failure to accomplish its objectives as far as the country’s reputation was concerned. Since Chelomei’s YMOS required relatively little new development, and could begin flying as soon as 1985, it was an easy sell. Moreover, it would build on continuations of existing DOS missions, with the nearer-future Salyut 5, 6 and 7 stations serving as testing grounds for both the YMOS-related equipment and the modular station philosophy.
¶
Unknowingly, all space hardware on both sides of the Iron Curtain was being prepared for launch in a very different decade. While the 70s have been dominated by the successes of detente, in which the superpowers strove to find peaceful solutions to hot-button issues through the gradual opening of bilateral relations (and sometimes concessions to the opposing ideology), some things never changed. Proxy wars continue to be fought worldwide with incredible human costs, with the superpowers sometimes covertly fanning local tensions or supporting the side benefiting them. Extensive espionage and the nuclear faceoff also continued, in attempts to catch violations of the many new treaties laid down, and predict the opponent's next moves.
With this dissonance running rampant, detente eventually unravelled as hardliners on both sides thought that this policy was giving the other side too much leeway. Some took this position for the sake of winning rivalries closer to home, between different departments and ministries.
The interventionism issue finally blew up in everyone's faces with the 1979 Soviet intervention in Afghanistan. There was thus a perception that detente had utterly failed; the hardliners were retroactively “proven” right, and majority public opinion shifted accordingly. As the 70s’ approach of carefully dismantling the vapid and ideological crashed hard, relations between the powers reverted back to aggressive posturing.
As for the space program, goodwill created by Apollo-Soyuz was tarnished; the anathema turned follow-up proposals such as a Shuttle-Soviet station docking and/or establishing a joint space rescue capability into political heresy, despite the benefits from creating a two-way window across both nations’ space programs. Only very low-profile cooperation, such as individual scientific investigations, could continue under this new political climate.
Author’s notes:
[1] This is inspired by the OTL Lockheed Propulsion suit against Thiokol.
[2] I messed around with the orbiter naming scheme for purely narrative reasons; to differentiate the ITL orbiters from OTL.
[3] To develop the YMOS, there may be some disregard of the OTL Soviet budget situation, but I imagine that the money could be available by not developing the RD-0120 ITTL.
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Was the RD0120 even that "expensive"? I've always had the impression it had a far easier development than RD-170
It was their first ever large Hydrolox engine and in the same weight and power class as the SSME so it can't have been cheap but I agree that it was probably cheaper than the RD-170. But you're not getting a space station out of the money saved. Initial studies into a space station however..
The biggest issue is that NASA does not really WANT to 'save' Skylab
First of all the station was still heavily damaged and there were questions on how much longer the 'fixes' were going to last.
Second was that it was never designed to be use beyond it's predicted life-span which was very much "in sight" by the point of the last mission.
Thirdly NASA didn't want to save Skylab because it would get in the way of the planned large scale space station they really wanted. Given that they got to 'save' the S1C booster they now have the option of an even BIGGER boosted module to play with rather than something that has to fit into the Orbiter cargo bay. So I'm very much afraid Skylab's going to auger in ITTL as well.
Randy
They have a booster but they don't have a second stage at the moment, and unlike the Soviets with their alt Energia no plan to develop one.
This is post-Apollo NASA, trust me SOMEONE has "plans" and likely studies about building a second stage AND the huge space stations to go on them. And then it's "On To Mars" while Congress cringes and curses... (and makes budget cuts)
Randy
This is post-Apollo NASA, trust me SOMEONE has "plans" and likely studies about building a second stage AND the huge space stations to go on them. And then it's "On To Mars" while Congress cringes and curses... (and makes budget cuts)
Randy
Oh I am sure there are a dozen plans for stages that you could stick on top of a S-1D from reworked S-II or S-IV's to big Centaurs to clean sheet fully reusable designs but there is no program of record. The Soviets do have a program of record.
It's something that has no reason to change; the Cold War paranoia (and its hundredfold amped-up version in the USSR) is still going to make the Shuttle out to be some warfare supertool, and evoke a matching response. Still, I imagine that abandonning the N1 is going to go over a lot less well than OTL, with the US reusing their Saturn V and whatnot.
Considering that the YMOS is going to end up in ITL Mir, it's not like "getting a whole additional space station."
That's one perspective I haven't seen much. The technical reasons for not saving Skylab are indeed really strong; it's a "Generation 1" space station incapable of many the things a 1980s space station needs such as modular racks for customers, resupply capability, waste disposal, etc. The only use case for saving it is really for its volume: making it a surrogate module to another station that can support itself even without Skylab.The biggest issue is that NASA does not really WANT to 'save' Skylab
First of all the station was still heavily damaged and there were questions on how much longer the 'fixes' were going to last.
Second was that it was never designed to be use beyond it's predicted life-span which was very much "in sight" by the point of the last mission.
Thirdly NASA didn't want to save Skylab because it would get in the way of the planned large scale space station they really wanted. Given that they got to 'save' the S1C booster they now have the option of an even BIGGER boosted module to play with rather than something that has to fit into the Orbiter cargo bay. So I'm very much afraid Skylab's going to auger in ITTL as well.
Randy
It's worth noting that this is EXACTLY what happened IOTL even with the really difficult sidemount configuration. In 1977, Boeing was contracted to look into these things as part of the Shuttle Derived Vehicles (SDV) study. Their final proposals consisted of (per Jenkins):
- Class 1 SDVs, which kept the ET and SRBs but swapped the orbiter for a cargo carrier; this resembled the later Shuttle-C as we know it.
- Class 2 SDVs, which is basically a more capable (by payload mass) Class 1, but the SRBs are swapped for a reusable Chrysler SERV-like "puck booster" attatched below the ET. This puck booster would have run on RP1/LOX, and was intended for 50 flights between each major overhaul. Of course, this meant changing up the GSE quite a bit, and so was less recommended despite being more efficient.
There were also station studies, many of which were ET wetlabs.
This is true, proposals for SEI or any equivalent will be a romp ITL.And then it's "On To Mars" while Congress cringes and curses... (and makes budget cuts)
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They started with the outcome they wanted; that Shuttle was a good idea. I actually think a Shuttle was a good idea in a build it and they will come way and really liked how "Right side up" explored that, it's just tragic they choose such an inefficient and dangerous design.
Ya at the time it seemed that NASA was seriously considering ways to save Skylab but with review, (and a lot of time learning how NASA really works
) it's pretty clear they weren't really interested and were more focused on a Shuttle based station. The volume on Skylab was great but if you read the reporting and mission logs it's not really 'usable' for what was planned for the next generation station.This is a perennial "issue" with space launch and/or space advocacy ideas in that it's pretty clear that more access to space is going to be a basic requirement to expand activity off-Earth and the "standard" analogy is a need for "aircraft like" operation which is kind of understandable but really not good at all. We still see this today, (see the expectations for Starship for a good example) but it's not truly "analogous" because space launch is very different than any other transport system we've had before specifically because of vastly different environmental requirements, lack of pre-existing markets and destinations, and variable economics. Flight rate is highly important for the economics to work and this was a basic 'assumption' baked into the Shuttle from the start, so much so that it was clear from the very beginning that the Shuttle HAD to be the primary (preferably only but there were enough 'marginal' payloads that the Shuttle couldn't economically or physically carry that some "other" launch capability had to be retained) launch means of as many payloads as possible. So it was regulated that all 'future' (once Shuttle was operational) payloads would be designed to and would go up on the Shuttle. (This had it's own down-stream effects)
The essential problem is it's highly unlikely (given even current tech) that very high flight rates can be achieved with only a limited number of vehicle because 'turn-around' times are going to remain well above those of (using the bad analogy
) say aircraft. Turn around times of "24 hours" are highly unlikely, a couple of days are "in theory" possible but still unlikely, probably the 'best' assumption is a couple of weeks at a minimum so to achieve a high fight rate you need more vehicles which costs more money in every aspect. Which actually runs into the 'reusable' versus 'expendable' problem because what we've learned is that if you need more reusable vehicles to achieve a certain flight rate then it's been shown that simply making 'cheaper' expendable vehicles is still actually economically comparable.So you end up having a choice to make for the underlying assumptions going forward. Since the Shuttle was always going to be 'reusable' which drove an assumption that it would be cheaper those were the basis of the concept. Yet any study of actual proposed and expected flight rates for the 70s and 80s showed there would not be enough payloads (therefore flights) to actually make the case for the reusable Shuttle versus a "cheap" expendable launch vehicle. So another 'assumption' thrown in was a very high flight rate which clearly showed the Shuttle leading the economics instead of a realistic assessment of the situation.
Rockwell actually since they were the ones building the Shuttle
One of my favorite "what if" scenarios and a timeline waiting to be written if I could actually think of a plausible POD but again this was a case of NASA not really wanting something they asked for/about. You see another 'assumption' on which the entire Shuttle design (and program) was based around was that every flight would be manned. (Because the "manned" part of the space program was king... Which isn't exactly wrong
)An SDV would have been able to fly unmanned which meant a flight taken away from the manned Orbiter which was unacceptable. No crew equaled no point to NASA management so the SDV never got (pardon the pun) off the ground.
Similarly the ET stations had a similar problem in that any such usage (or official support thereof) would take incentive away from the planned Shuttle supported and purpose built next generation space station that NASA wanted. So they idea died. Now while granting that "wet labs" have some issues, (see Boldly Going) there's good arguments for utilizing them but NOT if you're fighting a reluctant Congress with more than a bit of hostility involved to get funding for anything at the moment. Worse if you don't have the capability, personnel of funding to actually do such a job in the first place but "outsiders" keep pointing out what a good idea it is to said Congress which then turns and uses that as opposition to your planned modular space station.
Ya, NASA has a bad habit of not being able to read the room (aka Public/Congress) and kept/keeps shooting itself in the foot with the "All Roads Lead to Mars"/"Apollo 2.0 at only twice the budget!" stuff. If they had only laid low for a decade or so and let the pubic rebuild confidence and lulled Congressional hostility there was a public surge of interest coming to ride again (late 70s Space Colonization and the late 80s orbital/space interest spike) which in OTL reached Congress and lead to some actual support. (However brief) And then there's the Mars resurgence in the late 90s and early aughts that showed public support for Mars again....
But I suppose that's a lot to ask for an agency which has essentially just done the "impossible" (Apollo) to have humility and foresight to see it, let alone the institutional fortitude to act
Randy