A Skylab Shuttle timeline

This is a TL originally from alternatehistory.com that presents a world where the Skylab Program persisted.

Timeline
1969 

July 22 Men walked on the Moon the day before. NASA fulfilled Kennedy’s objectives of 1961. Now it’s time to think about the future.

The Skylab program officially starts. The big OWS will reach orbit in 1973, and Apollo CSM will visit it on regular basis. NASA plans to launch these CSM with Saturn IB from LC-34, as Apollo 7 did in October 1968.

1970 

May 15

LC-34 is in trouble. It is 10 miles away from LC-39, and not located at NASA Merrit Island. LC-34 is located on the USAF side of the KSC, at Cap Canaveral Air Force Station. NASA prefers launching its Saturn IBs from LC-39B, but the pads have been tailored for Saturn V. Saturn IB will take off from LC-39B on a milkstool.

1971 

June At a pre-launch press briefing for Apollo 15 Dale Myers, Associate Administrator for Manned Space Flight, spokes about the post-Skylab studies under way. He points out that there would be four Apollo CSM's left over, three from the canceled moon flights and one that had been set aside as a backup for Skylab.

Studies conducted in Houston indicated that these spacecraft could be flown in earth-orbital missions for about $75 to $150 million each. One possible use for these CSMs would be to launch one a year, beginning in 1975, for earth resources surveying missions lasting from 16 to 30 days each. Of these four spacecraft, one could be set aside for a rendezvous and docking mission with the Soviets. Still another possibility would be orbiting a second Skylab, using the backup CSM for the flight planned for 1973, but that would be very expensive and would require developing new mission goals for Skylab B.

October

Shuttle goes very, very close from cancellation. After rejection of Big Gemini, the Office of Management and Budget, and the Office of Science and Technology Flax sub-committee, both monitoring the shuttle program for Nixon White House, agree to force NASA accepting a glider ontop of an enlarged Titan III. George Low and James Fletcher hate the concept, preferring Mathematica’s TAOS (the shuttle we know today). Future of the shuttle look so bleak that Low asks Myers to keep LC-34 and Apollo interim flights on reserve, and seek how many Saturns IB are left.

November

Myers brief Low on Saturns boosters. SA-209 to 211 are complete; SA-212 gave its S-IVB to the Skylab program. SA-213 and SA-214 never received their S-IVB, but Chrysler completed their first stage (cluster) on its own funds. These first stages are in mothball at Marshall. Lots of J-2 are still hanging around, not mentioning Saturn V S-IVB -513 and -514 left. Completion of SA-213 and SA-214 would be quite easy.

Myers drafted a tentative list of flight hardware

CSM-119+ SA-209 (Skylab and ASTP rescue) CSM-111+ SA-210 (this flew OTL as ASTP) CSM-115 + SA-211 CSM-115A + SA-212

After what their would be no CSM left; hence refurbishing of Saturn SA-213 and SA-214 was not necessary.

1972 

January 5  '''Shuttle is approved by Nixon. '''

March  Decision to use solid rocket booster 

July 26  '''The orbiter contract go to North american Rockwell; boosters to Thiockol. '''

1973 

May, 25th

Alan Bean has to resign : Skylab A can’t be repaired. Its CSM can’t even dock with the wrecked OWS, and a rapid flyby show that Skylab hull is punctured by holes as big as Walter Mondale head. NASA will have to launch Skylab B from LC-39A within one year.

Dale Myers upgrade its list. Destruction of Skylab A left two more CSM and their booster. They are - CSM-117 and Saturn SA-207 - CSM-118 and Saturn SA-208 NASA had now five potential missions for Skylab B. A sixth CSM - CSM-111- is now due for ASTP.

June

Proposal from Douglas, builder of Skylab. Launch Skylab B with the ASTP – DM flight spare, to allow docking of the Shuttle in 1979. Nixon disbands the old National Space Council as uneffective and unuseful. After the bitter failure of the 1969 Space Task Group, the US space program has now nothing to steer it efficiently.

August 14

Final deadline for Spacelab. But NASA give ESA one more year, and changes Spacelab specs. Spacelab palet could be removed and replaced by an ASTP-DM for docking with Skylab in the late 70’s.

September 30 When sending its FY-75 budget proposal, NASA administrator James C. Fletcher asks for Skylab B. To achieve that, he sacrifices the Pioneer-Venus probes, and postpone Pioneer-Jupiter Orbiter Probe (JPO, future Galileo) by a year. He obtains satisfaction.

1974

August Marine One take off, carrying Richard Milhous Nixon far from the White House. Gerald Ford become president, and reminds how he helped creating NASA 15 years earlier.

September

Pioneer-Jupiter-Orbiter resurrects from the dead. Years before, NASA had broken JPL monopoly on space probes; Ames Pioneer thus competed with JPL Mariner- Voyager platform for Jupiter / Saturn flyby missions. The two centers also competed for the Jupiter – Orbiter program. Both wanted to built JOP from a spare probe Pioneer H or Voyager 3. Back in 1973, NASA had been on the verge to give JOP contract to Ames - before freezing of the program. Six months later, decision had been taken to give JPL again full monopoly on space probes. JOP studies had been transferred from Ames to JPL!

NASA management had turned JOP into an horrendous Pioneer – Voyager hybrid. Half of the spacecraft was spin-stabilized in typical Pioneer-Ames fashion; the other half of the ship was computer-stabilized in Mariner, JPL fashion! Spining was better to sample particles; it was disastrous for imaging a planet. This was called “spun/despun” and gave headaches to engineers. Freezing of the program probably saved the JOP program. It was now under strict leadership of JPL, and went as smoothly as Voyager before it. It earned its name Galileo in 1978. Despite serious setbacks with the Shuttle, Galileo accomplished 100% of its mission.

November

Saturn SA-515 take-off from LC-39A, carrying Skylab B in its flanks. Delays in launching the station were caused by modifications to the Multiple Docking Assembly. Skylab MDA features two docking ports. Apollo CSMs use to dock to the front port; the radial port is for emergency only. Problem is, CSM and Shuttle have different atmospheres. Skylab had to be adapted to one of the two atmospheres. Shall Skylab be adapted to Apollo oxygen-rich, 5psi atmosphere? to the Shuttle 15psi, oxygen nitrogen mixture? or something between the two ? Douglas had to answer these questions. Such problems have already been posed for ASTP. Indeed, Skylab atmosphere is quite similar to Apollo; while the shuttle will, quite ironically, have an atmosphere similar to the Soyuz. Hence, docking a Shuttle to Skylab B is just as tedious as docking an Apollo to a Soyuz!

The final report said

“Just like Apollo-Soyuz before, Shuttle and Skylab/Apollo spacecrafts provide their crews with different gas mixes and pressures. Astronauts and cosmonauts passing between Skylab and the Shuttle might prebreathe to adapt their bodies to the change in pressure and gas mix, though the time required will probably become onerous very quickly. Alternately, the sides could adopt a common atmosphere. Had the Shuttle kept Skylab's oxygen-rich 5 psi atmosphere, it would have required improved fireproofing and beefed-up thermal control systems to keep its electronics cool in the thin air. This is totally out of question since the Apollo fire.

The Shuttle 15 psi pressure has thus to be adopted. In this case, Skylab B would need substantial structural changes to withstand the increased pressure and extra tanks of oxygen and nitrogen to make up for air lost through accelerated leakage. Interim CSMs flights can not withstand 15 psi without suffering damage, so the capsules would need to remain isolated from the Skylab cluster. We planned a small airlock for prebreathing to be placed in the MDA for CSM access.

A better option would be a compromised 8 psi atmosphere slightly rich in oxygen. Modifications both Shuttle and Skylab would need to make would be roughly equivalent in magnitude. The Shuttle pressure can already be dropped to 10psi to ease EVAs. To limit modifications, simplified ASTP-DMs could be used to switch from oxygen-rich to oxygen-nitrogen atmospheres.

In conclusion Apollo, Skylab and the Shuttle could be unified around a 9psi atmosphere if simplified ASTP-DM were used to level small differences in gas mixture and pressure. “

Three interim CSM missions are planned, as with Skylab A. CSM-117, -118 and -119 have been specially built for Skylab years before. CSM-115 and CSM-115A will be held in reserve. A crew will not enter Skylab until completion of the ASTP flight, which has priority.

December

Salyut-4 reach orbit safely. After the death of Soyuz-11 crew and the successive failures of DOS-2, OPS-1, DOS-3, and Skylab A, the Soviet finally won the “space station race”.

The ASTP-DM is send to Skylab by an Atlas-Agena. The versatile upper-stage manoeuvers in orbit, guides and docks the 2000kg module to the OWS.

1975 

January

The House of Representatives refuse to fund the Large Space Telescope (future Hubble). Huge wave of protestation amid scientists led to the resurrection of the program. The National Academy of Science and its two dedicated space subcommittees played an important role. The efficiency of the National Academy of Sciences in the battle for the LST prompt president Gerald Ford to create a new space policy tool within the academy. It’s the SESC, Space Exploration Steering Committee.

January 11 – February 10

Soyuz 17. For the first time, a crew enter a space station and came back to Earth without problem. Record duration flight at 29 days.

May – July

New soviet duration record: Soyuz 18 crew spent 63 days at Salyut 4. NASA didn’t ever launched Skylab B…

July 25

ASTP. Last Apollo CSM to fly; a large gap began before the Shuttle first flight, planned for 1978, which already slipped various times. NASA starts modifying LC-39s for the Shuttle.

August

The newly-formed SESC starts to lobby President Ford and Congress for stretching the five Apollo flights to Skylab B over the next three years. These flights would fill the gap and reboost the station if needed. Two flights are already budgeted for FY76, soon to start. SESC representatives intelligently use recent soviet duration records to keep Congress under pressure. NASA can’t sit down and watch the soviets beating flight duration records. The SESC obtains satisfaction, and two more Apollo flight to Skylab B are included. Most importantly, decision is taken to keep Skylab B alive until the Shuttle enter service.

October

First flight to Skylab B. Crew spent 30 days at the station. They prepare the station for the next flight, which will attempt to break the soviet record.

1976 

May 1st - July 4th.

Apollo “bicentennial flight”. Second flight to Skylab B. Three astronauts celebrate 4th July onboard the station, beating the soviet duration record the very same day (65th day in orbit). By a bizarre twist of fate, this crew launched from LC-34 on May 1st, Soviet Labour day… record duration flight at 70 days.

1977 

March – May

Third flight to Skylab B. A crew spent 84 days at Skylab B and reboost it. Carter and Mondale threatens to cancel remaining flights.

December Salyut-6 reach orbit safely. The soviets are not long at bereaking the US duration duration record. Salyut-6 EO-1 mission spent 96 days in orbit.

1978

Due to pressure from Carter and Mondale the last two Apollo flights have not been budgeted. The SESC battle the decision, citing Shuttle serious problems and cancellation of the fifth orbiter. Klaus Heiss propose to privately fund the fifth orbiter – via its Spacetran consortium – or the last two Apollo flights. SESC arguments finally prevail, and the last two Apollo flights are funded.

June – November

New 139-days duration record by the soviets. This is definitevely beyond reach of any Apollo CSM. Young pledge for a 100+ day stay is dismissed as too dangerous. Apollo can’t withstand flight duration over 90-days, and there's not enough CSM to rotate crews in soviet fashion.

NASA has now to decides if it will take again - or not - the record duration to the soviets.

First move in this direction is the EDO program. The Shuttle is modified at the time into the Extended Duration Orbiter - EDO Shuttles will stay 16 days in space, later brought to 28 days.

Beyond that appeared the problem of bailout.

To solve this problem, NASA allows North American Rockwell a 18month contract to study a rescue, 6-man,land-landing, upgraded Apollo Command Module. It will be carried by the Shuttle every 90 days, and docked to Skylab MDA radial port by the Canadarm.

As a secondary fonction the capsule could be used as a Shuttle Escape System. The crew would access the CM via a tunnel; they would wear pressure-suits to avoid difference of pressure between Apollo and the Shuttle. After what the payload-bay door would be ejected, an Apollo would blast off using its retrorockets.

1979 

February (up to October 1980)

Two more records on the soviet side : 175 days, followed by 184 days.

March

Morale at NASA is low, amid Shuttle delays and cost overruns. Tiles are falling, SSME are exploding on the bench… while solar activity is harsh, threatening Skylab B. A fourth flight to Skylab, lasting 45 days, finally boost morale and the station.

November NAR contract for Apollo CRV concludes. The Carter administration refuses to fund the CRV, limiting the usefulness of the station.

1980 

Delivery of Spacelab 1 to NASA, with the pallet replaced by the spare ASTP-DM.

August

The very last Apollo ever, visits Skylab B and reboost it for the last time. Flight duration : 65 days.

November

POTUS Ronald Reagan.

1981 

April

First flight of the Shuttle. In the wake of sucess, Reagan agree on Apollo CRV. NAR resume production. CSM-119 is changed into a CRV mockup.

November

STS-2 carry the modified Spacelab, and dock with Skylab B via the ASTP-DM. Spacelab and the ASTP-DM are connected via an APAS-75. With Skylab in sight, the doors of the payload are open. Spacelab and the ASTP-DM twist by 90°. The ASTP-DM dock to Skylab via a probe-and-drogue system from Apollo. The crew leave Columbia cockpit, enter Spacelab pressurised-module via the tunnel, then head to the ASTP-DM, then into Skylab B.

1982

STS-3 carry the modified CSM-119. It is docked to Skylab MDA radial port until the next Shuttle launch.

New soviet duration record : 211 days from May…

1983

March Reagan decides to expand Skylab B. An upgraded ASTP-DM will go to the front port, then a "node" will be added. The node will have four docking ports for enlarged, autonomous Spacelabs pressurised modules. In the long term, the aeging Skylab could be replaced by a New Large Module launched atop a Shuttle-C. To fill the gap, an "interim power platform" would have to be built.

August

Challenger carry the first CRV to Skylab B. CRV-121 is berthed to Skylab radial port (on the side of the MDA). The US crew is now ready to beat the soviet 211 days duration record.