A Sound of Thunder: The Rise of the Soviet Superbooster

Interlude : Report to Congress

Interlude : Report to Congress​


- Soviet Space Programs 1971-75, Staff report prepared for the Committee on Aeronautical and Space Sciences, United States Senate, August 30, 1976.

B. Soviet Political Uses of Space

1. The climate in 1971
In 1971, the Russians in their media seemed more devoted to attacking U.S. policies related to Vietnam than in recognizing successes in the Apollo program. The unmanned Lunokhod rover was touted as a better approach than the high cost and risky manned Apollo flights. An earlier theme of attacking the American space program on the grounds of its militarization had largely disappeared. The Soviet space program was still described in terms suggesting its high degree of perfection. Apollo was described as a risky aberration, while the true path to further progress was linked to Soviet successes in Earth orbit and a gradual expansion into deep space using their new Groza rocket. Soviet leaders gave high visibility to the Soviet space program and their personal links with it. Emphasis was put on the practical benefits which would flow from the program. The achievements of the Almaz space station missions, with a public emphasis on the monitoring of Earth’s environment from orbit, played into this narrative.

2. The Climate in 1975
In 1975, the climate was quite different. The Apollo-Soyuz Test Project received tremendous attention and was heralded as a building block to further improvement in relations between two partners of similar capabilities in space. Of necessity, there was some easing of space secrecy on the part of the Russians as a condition of the co-operative effort. At the same time, the political uses of space to glorify achievements of the Soviet system continued, and there were sharp limits to the amount of openness.

2. Characteristics of Space Relations

a. Absence of familiar Soviet themes and actions

(1) No downgrading of American space effort. - Discretion was the most significant characteristic of Soviet space relations with the United States during January-July 1975. Absent were some of the familiar themes and political actions characteristic of Soviet space politics during the most intensive periods of the Cold War. There was no downgrading of American space programs or activities. Allegations of American critics that the Soviet Union gained more from the joint mission than the United States appeared to be met by and large with studied restraint. Such assertions were politely rejected with reminders of the difficulty in getting sufficient congressional appropriations for carrying on the American manned space program, and experience not shared by the Soviet Union, and that the one-sidedness in going forward with ASTP, therefore, really benefited the American side. However, Soviet interests would not suffer, it was said. Both sides would really be the beneficiaries from a joint enterprise that furthered the cause of detente, cooperation, and peace. American space officials were cited to dispute the charge of an uneven technological transfer to the Soviet Union.
Sharper rebukes to this allegation took the shape of counter-charges that the critics were opponents of detente. Yuriy Zhukov, a leading Soviet publicist, referred to such critics as “demagogues in the U.S. who stand against scientific cooperation with the U.S.S.R.” In reply to such critics, he said: “It is not accidental that U.S. firms are buying ever more licenses for inventions from us.”

(2) Easing of restrictions on secrecy. - Evidence of an improving Soviet attitude in space relations was apparent in the easing of restrictions on secrecy. In the course of preparations for the Apollo-Soyuz mission the Soviets admitted, albeit reluctantly, American officials and astronauts to areas of space work heretofore held in the greatest secrecy. Preparations had apparently gone smoothly until the Apollo crewmen insisted on touring the Tyuratam Cosmodrome, inspecting the Soyuz launch pad, and visiting the Soyuz spacecraft. Air Force General Thomas P. Stafford, commander of the Apollo spacecraft, said: “I never fly on a spacecraft I haven’t been in on the ground.” Reluctantly, the Soviets agreed to the visit, in conformance, it might be added, to the principal contained in the April 6, 1972 agreement on the joint flight. NASA project officials had uniformly insisted and gained agreement that American crews had to be familiar with the actual Soyuz that would participate in the mission.
On their four visits to the Soviet Union the astoronauts also visited Star City, the cosmonaut training center 30 miles outside Moscow. Americans also spent hours touring and working at the space control center at Kaliningrad, near Moscow. As Astronaut Donald K. Slayton said in Moscow, “We have seen everything we need to see to fly this mission effectively.”
Such openness along with a willingness to permit “live” TV coverage of the mission stirred favorable comments in the West. One optimistic Western diplomat in Moscow contended that the mission as a whole was significant. “This whole system has been built on a threat - a threat from outside to destroy the country,” he said. “It’s a major step to take away the enemy.” He argued that the decision to let down the secrecy barriers and open up the Soviet space program as much as the Soviets did could have wider effects in this “very cautious, bureaucratic system.” “When the genie gets out of the bottle,” he suggested, “it’s very hard to put it back.”
One Soviet science writer was similarly optimistic. “This secrecy… bothers us too,” he said, adding, “But I think this will change. As cosmonauts train with your astronauts, as our people go more and more and see how you do things… I think they will begin to loosen up.” Another prophesied: “I cannot be sure. But I begin to see a few green shoots in the frozen ground… If we cultivate these, if we don’t expect too much but cherish each sprout, I think eventually we will have a garden.” The Apollo-Soyuz information flow, said Robert C. Cowen, science writer for The Christian Science Monitor, “may be the first flowering of that garden.”

B. Presence of familiar Soviet themes and actions
(1) Exaggerated claims for Soviet space efforts. - Despite the respect shown regarding American space achievements, characteristic exaggerated claims for Soviet space efforts continued to be made. The successful 58-day orbital flight of Soyuz 16-Zarya in April-June, the longest Soviet manned space flight, was a major triumph, and media coverage was extensive and positive. American observers opined that the flight would further bolster Soviet self-confidence following successes with their Almaz program.
Soviet pride must have been further encouraged by the sending in June of two automatic space stations, Venera 9 and Venera 10, in the direction of Venus. Space specialists in Moscow believed that at least in part the stepped-up Soviet activity in space (in addition to these major launchings, the Soviets orbited numerous smaller satellites) was intended to demonstrate competence in a broad range of space systems and dispel the impression that the Soviet space program was in trouble. The Venus probes, the first in three years, served to remind the world that the Soviet Union had made the only successful landing on Venus.
That the Soviets were gaining in self-confidence by these achievements prior to the Apollo-Soyuz mission was evident by the tone of confidence and satisfaction that marked their reports on the Soyuz 16 mission, and the strong implications by Soviet specialists that Zarya would be used by many successive crews manning the orbital station in shifts ranging from a few weeks to months. To the discerning observer the Soviets could also be seen to draw confidence from the belief that by participating with the United States in a joint mission on the scale of Apollo-Soyuz they were able to demonstrate effectively that they had achieved parity in space.
Thus, solid and highly visible achievements in space had made it possible for the Soviets to again flaunt their successes as they had done in the past, although in keeping with the spirit of détente and the style of the Brezhnev regime, the emphasis was placed on demonstrating Soviet competence in space and parity with the United States.

3. Political Significance

c. Soviet gains in prestige.
- That the Soviet Union gained in prestige as a result of the successful joint flight is apparent from reactions at home and abroad. To have the demonstrated technical and scientific capability of participating in such a complex operation with a space power so advanced in space science and technology as the United States cannot have escaped the attention of an attentive world. What no doubt added to the global popular appeal of the mission was the visual proof that the two superpowers with basically conflicting social systems and many diverging national interests could indeed cooperate in such a dramatic undertaking on a common basis of detente.

d. Intensity and depth of Soviet space commitment. - Finally, Soviet space activities in this period suggest the depth and intensity of the Soviet commitment to space exploration. On visiting the Soviet space center near Tyuratam, Astronaut Stafford reported that from the amount of construction under way, the Soviets were “dedicated” to pursuing the goals of their space program.
The American astronauts said that they were impressed by the “tremendous effort” the Soviet Union was putting into its space effort.
Despite restrictions placed on their movements by the security-conscious Russians, American space specialists had seen enough, in the words of one report, “to convince them that the Soviet Union is continuing to put vast resources into its space effort.” Referring to assembly sheds that the visiting party saw scattered throughout the area near the Baykonur cosmodrome, as well as work evident on the launch pads of their Groza heavy rocket, Astronaut Slayton said, “I’d be surprised if they weren’t working on some advanced technology… but we didn’t see it.”
Moreover, published statements by Soviet space scientists and cosmonauts suggest extension rather than retranchement of the Soviet space commitment.
Given the Soviet inclination to view such scientific enterprises in a political context, all of this suggests the high political value that the Soviet leadership places on space exploration.


Thus, consideration of future prospects for Soviet-American space cooperation logically begins within the parameters of political relations and a determination of the durability of detente. As Chapter One suggests, detente is now being put to a great test as 1975 comes to a close: the Soviet Union and the United States have come to grips with the issue that lies at the very heart of the concept; namely, military detente and efforts to resolve differences in SALT II and MBFR negotiations. Aggravating the environment of relations is also Soviet intervention in Angola. Still, a more fundamental and discordant element working against the purposes of detente, in addition to the inner dynamics of the great power conflict that underlay Soviet-American relations, is Soviet insistence that there can be no detente in ideology and that the “struggle” against world capitalism (i.e. the United States, its allies, and non-Communist countries), perceived in multiple ways, must continue. (Figure 4-1 graphically portrays the presently existing adversarial relationship between the Soviet Union and the United States; a handshake in space - ASTP - becomes an arm-wrestling match on Earth). Accumulating evidence by the end of 1975 suggests to some observers of the Soviet political scene that an internal debate is now taking place on the merits of detente and the desirability of changing that policy to a more aggressively oriented revolutionary line. Advocates of this approach urge taking political advantage of what they perceive to be a “weakened” international capitalistic system.
Placed in the context of growing American disenchantment with detent which has been fed by a durable distrust of the Soviet Union, these developments suggest that detente in Soviet-American relations is heading for trouble. A countervailing factor to this tendency is the belief that both sides, faced with the common danger of nuclear war in an environment of deteriorating relations and judging relationships from the position of realism, would want to pursue a policy of negotiation, not confrontation.
It is, therefore, in the continuation of détente that advocates of space cooperation must seemingly place their hopes for the future.


Figure 4-1
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Apart from the bit about the Groza rocket that could have all come from OTL and I'm guessing is based on an OTL document of a similar time.
Apart from the bit about the Groza rocket that could have all come from OTL and I'm guessing is based on an OTL document of a similar time.
More or less, though the OTL version notes the Soviets are not bragging as much, because they've had more high-visibility failures. That's why it's in an Interlude. It sets the political scene for the next post.
Wiki lists Saturn-V at 140t to LEO (for what that’s worth), so Groza still falls short - but it is significantly larger than NASA’s then current program-of-record, with consequences we shall explore on Friday…
wiki is not reliable source !
i look into Saturn V Payload Planners Guide by Douglas 1965
The Saturn V three stage was design to launch payload out Earth gravity field either to Moon Mars or GTO

After Apollo by Numbers is Orbital mass of S-IVB/SLA/LM/CSM into 186 km orbit.
127878kg (Apollo 11 mass can vary on other Apollo missions)

All design of Improve Saturn V i know for Heavy payload into LEO were Two Stage variants.

Mass-wise, Buran could be launched on N-1, but as you note, the problem is the wings.
Had Soviets Orbiter wings like the Space Shuttle.
The N1 needed giant wings for Block A, like Von Braun Ferry rocket, to counterbalance the Rocket during Aerodynamic ascent.
That would be nightmare to adapt the N1 to that, to use Orbiter with folding Wings is brilliant solution but bring another problems.
wiki is not reliable source !
i look into Saturn V Payload Planners Guide by Douglas 1965
The Saturn V three stage was design to launch payload out Earth gravity field either to Moon Mars or GTO

After Apollo by Numbers is Orbital mass of S-IVB/SLA/LM/CSM into 186 km orbit.
127878kg (Apollo 11 mass can vary on other Apollo missions)

All design of Improve Saturn V i know for Heavy payload into LEO were Two Stage variants.
I believe 140 tons is the LEO payload capability of Saturn V with the S-IVB still attached. You'd have to burn up the entire S-IVB to do it, but it could be done.
Had Soviets Orbiter wings like the Space Shuttle.
The N1 needed giant wings for Block A, like Von Braun Ferry rocket, to counterbalance the Rocket during Aerodynamic ascent.
That would be nightmare to adapt the N1 to that, to use Orbiter with folding Wings is brilliant solution but bring another problems.

Nah, it's easy, look!
Will there be more missions with other countries from the Eastern bloc in connection with the improvement of the image of the Soviet spacecraft?
Post 10: US Responses

Post 10: US Responses​

“In Washington, few things are so permanent as a temporary solution.”

- Dennis R. Jenkins, “Space Shuttle: Developing an Icon


The United States was slow to respond to the steady increase in Soviet space capabilities as the 1970s progressed. Following the triumph of the Apollo programme, NASA transitioned its focus to development of the Space Shuttle, which was to provide frequent, economical access to orbit by the end of the decade. Apollo hardware continued to be flown with the Skylab missions in 1973, and the joint Apollo-Soyuz mission with the Soviets in 1975, but after this NASA paused all crewed space missions to concentrate its resources on the Shuttle. The remaining Apollo capsules and Saturn rockets were to be handed over as museum exhibits, while Skylab was left un-tended in orbit, hopefully to be visited by one of the early Shuttle missions.

Although NASA appeared confident that the Space Shuttle would render large expendable rockets like the Saturn V and Groza obsolete, this view was not universally shared. With approval of the Space Shuttle programme in 1972 being quickly followed by the Soviet Groza/Zond 9 mission later that same year, lawmakers began to express concern that the USA was giving up a hard-won lead in heavy launch vehicles just as the USSR was expanding their capabilities. The impressive Zond 10 and Kosmos 676/7 missions of 1974 re-enforced this view, but it was the 1975 launches of the Zarya space station that really set alarm bells ringing. Zarya was seen as a harbinger of future heavy, militarised Soviet space bases, which might be used to develop capabilities in particle beam weapons and large, super-sensitive space based radar arrays.

Despite NASA’s official assurances that the frequent and economical operations of the Space Shuttle would enable missions of equal or greater ambition at lower cost, senior members of the Senate Committee on Aeronautical and Space Sciences were not convinced, and during the FY1976 budget hearings an appropriation was added to the NASA budget to delay the handover of Apollo hardware to museums and instead keep it in storage, in case there should be a need to rapidly respond to some Soviet advance before the Shuttle could be made operational. NASA administrator James Fletcher accepted this directive, but pointed out that the launch pads at Kennedy Space Center were planned to be remodelled over the coming years to support the Shuttle, meaning that equipment necessary to launch the preserved Saturn V’s would be gone by 1977. At that point, the USSR would become the definitive owner of the world’s most powerful space launcher].

As evidence mounted of further improvements being made to the Groza rocket with the addition of hydrolox stages, even as the Shuttle programme suffered delays, the situation became increasingly difficult politically. This was especially true during the run-up to the 1976 Presidential and Congressional elections, as although space did not feature prominently in most voters’ or candidates’ minds, the apparent ceding of space leadership to the Soviets did feature as part of wider attacks on President Ford’s record. Taken together with his decision to pardon Nixon, the fall of South Vietnam, and a struggling economy, talk of falling behind in the space race fitted into a narrative of Ford having overseen a period of US decline.

In fact NASA was already looking at alternatives to Saturn V for launching large payloads, with a contract jointly awarded to Boeing and Grumman to assess options for a shuttle-derived heavy lift vehicle. The objective was to explore possibilities for a heavy launch vehicle that could co-exist with Shuttle, while minimising any impacts on the Shuttle’s development program. The study received a boost in funding and priority in early 1976, and the final report was issued in September of that year[1].

The report investigated several options, but the one received with most interest at NASA was the “Class-1” or “SDV-1” concept. This would use the exact same External Tank and Solid Rocket Boosters as the Space Shuttle, but replace the orbiter with a recoverable boat-tail containing the engines, plus a large expendable launch shroud. Payload to LEO was projected to be around 70 tonnes, just 60% of that of Saturn V and comparable to Korolev’s original N-1 design, but it had the advantage of maximising re-use of Shuttle hardware and facilities. This would dramatically cut the amount of money and time needed to develop the system. The study also speculated that the initial SDV-1 could later be evolved and expanded to an in-line configuration capable of matching Groza’s 105 tonnes to orbit, though it provided few details on the specifics of this upgrade.

The study was well received within NASA (except for inside the Astronaut Office, which was pressing to ensure that all launches carried crews), and also in government as a relatively cheap and fast way to respond to concerns over a perceived capability gap with the Soviets. This broad support meant Administrator Fletcher was able to persuade the Ford administration to include in their final budget proposal a 10% increase in the Shuttle budget line for initial development of the Shuttle-Derived Heavy Launch Vehicle. After some tug-of-war in the new Congress between fiscal hawks seeking to cut the budget and Cold Warriors keen to counter the USSR, this figure was reduced to 6%, and in December 1977 NASA issued a contract to Rockwell to begin development of the SDHLV, which was now given the name “Shuttle-C”.

The reduction in the development budget imposed some changes to the design of Shuttle-C, with the most significant being the deferral of plans for a recoverable Propulsion and Avionics Module. The Shuttle-C Propulsion and Payload Module (PPM) would now be fully expendable, sacrificing three RS-25 Space Shuttle Main Engines with every flight. Engineers at Marshall proposed reducing the impact somewhat by enabling two- or single-engined versions where the full payload capability was not needed, but this didn’t reduce the number of eyebrows raised in Congress that NASA now proposed to throw away copies of its expensively developed reusable engine.

Other proposed cost-saving measures included the deletion of the Orbital Maneuvering System engines in favour of an upper stage, such as the planned Centaur-G, in the payload bay to push the Shuttle-C’s cargo into orbit. However, the development of Centaur-G had not yet been authorised, and pad modifications to allow fueling of the stage were not in the budget, so in the end NASA accepted the marginally higher operational costs of flying with an OMS.

All this was an echo of what had happened to the original Shuttle design, with re-usability sacrificed in order to lower up-front costs, at the expense of increasing recurring costs in operations. In the final design, the Solid Rocket Boosters would be the only part of the Shuttle-C stack to be re-used. As with most of the other compromises made to fit the allocated budget, NASA pinned their hopes on future upgrades to improve performance after the system started to fly.

The Payload and Propulsion Module design would consist of a more-or-less unmodified Shuttle orbiter boat-tail (maintaining compatibility with the crewed Shuttle ground interfaces), but with a few changes to lower its weight. As the structure would no longer need to be rated for 100+ launches, some mass savings could be realised by reducing structural tolerances and swapping out some titanium components for cheaper aluminium alternatives. Similarly, the thermal protection tiles could be omitted, replaced by a cheaper coating to withstand aerothermal loads and heating from the propulsion system.

At the front of the PPM was an all-new Cargo Carrier element. Although the idea of simply removing the wings and crew compartment from a standard orbiter was suggested, this was rejected as it imposed too great a penalty on performance. The high structural mass of the orbiter body would have to be subtracted from the payload, and in terms of volume, fitting a 60+ tonne payload into a space intended for 25 tonnes was not ideal. In the end, the basic configuration chosen was a simple cylinder, 7.6m in diameter and 27.4m long, ending in a cone. The bottom half of the Carrier was integrated with the PPM, providing a strongback attached to the External Tank, while the upper half would be jettisoned to allow release of the payload.

With Shuttle-C development now underway, and with the first launch projected as soon as 1980, thoughts turned to what payloads could take advantage of the new capability. The most obvious answer was a large space station as a response to the Soviet Zarya, but the funding to develop such a station was simply not there, and in any case, the US still had Skylab in orbit, making a new station hard to justify.

This last assumption was coming under increasing scrutiny by 1978. Following the last crewed mission on Skylab 4 in 1974, the space station had been boosted into a 433km x 455km orbit that NASA assumed would keep the station in space into the early 1980s. By late 1977, an unexpected increase in solar activity expanding the upper atmosphere meant that NORAD now expected Skylab to re-enter the atmosphere in mid-1979. Although NASA continued planning for a possible Shuttle rescue mission, unofficially most within the Agency accepted that it would not be possible to rescue Skylab.

At the same time, the December 1977 launch by the Soviet Union of the Zarya 2 space station again highlighted the apparent gap opening up. At least as large as the original Zarya station, official Soviet reports were describing Zarya 2 as “the world’s first modular orbital complex”, suggesting that the station would be expanded further over time. In contrast to the first Zarya, missions to the new station were secretive, hinting at a predominantly military purpose more aligned with the Almaz stations. With the return of Americans to space in the Shuttle not expected for a further two years, the press and political class in the US demanded a response.

However, NASA believed it had found a near-term option that would not only provide a strong foundation for a permanent American crewed presence in space, but would do so without breaking the bank. First explored as an option in 1977, the NASA budget request for FY 1979 asked for modest funding to prepare a 60-tonne station module to be launched on one of the first flights of Shuttle-C, within two years of the start of the programme. This station would be visited by the Shuttle, and could be expanded over time with additional modules carried in Shuttle’s payload bay. Development of the additional modules could be postponed until after the funding for Shuttle development had moved off the books, or could be passed to allied nations, in an extension of the approach being used for the ESA-built Spacelab modules planned for the Shuttle.

Of course, the development of a large space station module from scratch in less than two years for a fraction of the funds being spent on even the Shuttle-C was completely unrealistic. Fortunately though, NASA already had a large, flightworthy space station module available and sitting in storage: Skylab-B. With some modifications, the backup Skylab module could provide NASA with an orbital destination for the Shuttle, and an ongoing project to build upon in the 1980s.

As with the Shuttle and Shuttle-C programmes before it, Skylab-B was heavily budget constrained, with modifications kept to the bare minimum needed to meet initial needs while driving costs down, and accepting the inevitable technical debt this imposed. Additionally, there were technical constraints coming from the change of launch vehicle (launching on Saturn-V no longer being an option due to changes in the pad infrastructure).

The first and most pressing of the technical constraints was mass: at 75 tonnes, a straight duplicate of Skylab-A would be too heavy to launch on Shuttle-C. The need to lose weight meant the immediate deletion of the Apollo Telescope Mount, removing 11 tonnes from the station. The Airlock Module was retained, but six tonnes of consumables stored in the module were removed, on the basis that each visiting Shuttle would carry the bulk of provisions needed for a given mission. This rationale also allowed the removal of four tonnes of food and water from the Orbital Workshop, saving around 10 tonnes on launch mass.

The Multiple Docking Adapter, originally intended for visiting Apollo capsules, had to be completely replaced. The docking port was not compatible with the androgenous docking adapter planned for the Shuttle’s External Airlock[2], and in any case was not rated at the atmospheric pressures used for Shuttle. The MDA was therefore removed, and a new Shuttle Docking Module was designed, derived from the External Airlock. At around 2.2 tonnes, the SDM would be almost a third the mass of the old MDA, aided by the fact it would no longer have to hold control equipment and film for the deleted Apollo Telescope Mount. Consideration was given to providing the SDM with multiple docking ports, so it could act as a node for the addition of future modules, but this was rejected in order to save both mass and budget. It was reasoned that a dedicated node module could always be added at the axial port if needed in the future.

One issue weighing heavily on the minds of NASA engineers was the topic of propulsion for the station. With Skylab-A even then falling from the sky, it was quickly decided that Skylab-B must have a re-boost capability from day one. Ideally, this system would be mounted at the base of the Orbital Workshop, on the opposite side from visiting Shuttles, to avoid interference with any future modules that would be added to the station, but this posed several problems. Firstly, it would interfere with the OWS’ radiator, which was already in this position. Secondly, locating the propulsion system at the opposite end of the station from visiting Shuttles would make refuelling operations extremely difficult. This would require either a long (and heavy) set of pipes and pumps, or the orbiter performing an elaborate and risky manoeuvre to approach the rear of the station just for refuelling.

The alternative was to position the reboost engines at the ‘front’ of the station, around the Shuttle Docking Module. This would give easy access from the Shuttle payload bay, and had the added advantage of producing thrust loads similar to those already studied as part of planning for a possible reboost of Skylab-A. In the end, the two engines of the Main Station Propulsion System (MSPS) were added either side of the Airlock Module in the thermal shroud of the main station body, with refuelling lines running up the outside of the AM to the Shuttle Docking Module.

With the development of Skylab-B approved in October 1978, the United States now had a plan in place to meet the Soviet challenge in Low Earth Orbit in the early 1980s. However, by this stage it was becoming increasingly obvious that the Soviet challenge was already moving deeper into the cosmos...


[1] This study was commissioned IOTL, but didn’t get the priority boost, so delivered the final report in September 1977.

[2] IOTL development of the External Airlock was deferred in 1976 as a cost saving measure, before being revived to support Shuttle-Mir in the 1990s. ITTL it is revived in the late ‘70s to support Skylab-B.


Note: I'm hoping to have some artwork to accompany this post soon. I'll edit it in as soon as it's available.
Taken together with his decision to pardon Nixon, the fall of South Vietnam, and a struggling economy, talk of falling behind in the space race fitted into a narrative of Ford having overseen a period of US decline
One reason I didn't vote for Peanut, was for his VP choice, Mondale, who was no friend of the Space Program.
I considered Fritz to be Proxmire's 'Mini-Me' in that regard.
Honestly, this is all a fairly logical progression and pretty much what I might have expected had I sat down and thought about it (rather than leaving that to you, dear author!) I believe we already discussed how Shuttle-C is the easiest and most straightforwards way to get a heavy-lift capability out of the Shuttle, especially if you're going to be operating Shuttle itself in parallel.

Modifying Skylab-B, while not precisely trivial, is also a pretty good stroke--compared to the obvious alternative of Space Station Enterprise/Challenger (depending on which test article you decide to sacrifice to the station gods), it requires relatively less upfront development and is much more "productively" massive (less weight wasted on Orbiter structure, that is). And compared to a proper modular station it's cheaper and faster to development...at least in theory (well, compared to Freedom/ISS, almost anything would be cheaper and faster). Besides, at this stage they don't know that Enterprise is going to be too expensive to modify into a flight orbiter, so there's no reason for them to sacrifice one of the test articles when they can just pull Skylab-B out of storage.
Before someone say "hey let take the two Saturn V and Launch Skylab B ?"

It will not work, because the Shuttle program
in 1977 Launch pad 39A/B have undergone modifications for Shuttle launches and become incompatible to Saturn V launch.
The CSM went to Museum and Saturn IB and Saturn V on public display

There is one issue that worry me, Skylab B went December 1976 to the National Air and Space Museum in Washington, D.C.
I wonder if they willing to give it back ?
There is one issue that worry me, Skylab B went December 1976 to the National Air and Space Museum in Washington, D.C.
I wonder if they willing to give it back ?
That was discussed in the post:

Despite NASA’s official assurances that the frequent and economical operations of the Space Shuttle would enable missions of equal or greater ambition at lower cost, senior members of the Senate Committee on Aeronautical and Space Sciences were not convinced, and during the FY1976 budget hearings an appropriation was added to the NASA budget to delay the handover of Apollo hardware to museums and instead keep it in storage, in case there should be a need to rapidly respond to some Soviet advance before the Shuttle could be made operational.

So Skylab-B has been sitting in NASA's warehouse for a few years instead of being handed over to the Air and Space Museum.
Well NASA already has a brighter future ahead itself in this timeline already with a working Shuttle-C by the 1980s.

But I still don't have much, if any faith in Congress to somehow not screw over nasa in the coming years.
It is, conceivably, possible to do a Shuttle-carried LH2 upper stage without significant modifications to the pad. Boeing studied the concept and built some prototype hardware right before STS-107 IOTL--the idea was to fill the tank only after SRB separation with residuals from the ET. IMO, that was quite an elegant solution to the problems that dogged Centaur-G IOTL--maybe they'll hit on the idea ITTL too.

Deleting ATM is pretty much a no-brainer at that point--film cameras being well on the way to obsolescence at that point.
An excellent update! Glad to see what's going on on the other side of the Iron Curtain. Skylab B is always a nice touch, too- and Shuttle-C from the beginning, very promising.
Well, that's one upshot of the STS architecture making itself known here - Shuttle-C should open up new options for NASA to take/review.

And at least Skylab-B appears to have a real chance here, if nothing else, the continuing 'Red Scare' will make sure of that.

Should make the 1980's interesting...