June 1973 : Skylab A is not salvaged

Archibald

Banned
Merci!

Or maybe private space entrepreneurship performs better in the 80's ?

And by 1994 they are able to replace Skylab by a russian-based space station ? either the old Salyut 7, Almaz, Mir, or its backup ?

By the way, if NASA give up the "commercial shuttle" dream in 1975 (having a space station instead to justify the shuttle!) there's no need

killing Titan Atlas Delta
killing private rockets and initiatives
(such as Faget Industrial Space Facility)

NASA is pushed outside LEO by the private sector or ESA, and has to turn to lunar mission again... :D

But your "modern Skylab" launched by a Shuttle C is very tempting!

I'll post an upgraded variant of this TL...
 

Archibald

Banned
Done!

A SKYLAB-SHUTTLE ATL.

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.

1984


February - June

Soviet duration record at 237 days.
 
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Archibald

Banned
wonderfull TL !

here some note on space hardware lifetime

MIR space station lifetime 15 year (deorbit for ISS)
ISS space station lifetime 19 year (start 1998 - deorbit 2017)

so Skylab B launch in 1974 can be used until 1989-1994 !

so wat after Skylab B ?
one is build Space Station Freedom at Skylab B
http://en.wikipedia.org/wiki/Space_Station_Freedom

and get same ISS problems :(

but there better way !
build Skylab C and launch as shuttle C :D

in 1993 this was Option C in US space Station plans

http://www.astronautix.com/craft/spas1993.htm
http://www.astronautix.com/graphics/d/diag93c1.gif
http://www.astronautix.com/graphics/o/optionc3.jpg
http://www.astronautix.com/graphics/d/diag93c2.gif

Michel, your mention of Shuttle-C give me ideas.

OTL the Shuttle-C was dropped because its costly SSME burned in the atmosphere at the end of the mission.

NASA planned to use worne-out SSME from older missions, but the stock was too little.

What about salvaging Shuttle-C's SSME in orbit ?

I mean, remove them with the canadarm, put them in a Shuttle payload bay, and bring them back to Earth for reuse !

By the way - small upgrades to the story -
 
Dear god you are going the complicated way.
Since the POD is in the early '70es you can scrap most of OTL Shuttle architecture and do something smart. Like i dunno, cloning Energia/Zenith/Buran system. One main rocket that can be scaled from 50-150 tons payload, a booster that can be used independently as a light payload LV, and a spaceplane as a pure payload.

Keep the main engines where they should be, on the launch vehicle. And dont even try to make them reusable, costs way way too much. Keep the god damned fancy pancy spaceplane as only a payload.


Or if you want to have something fancy... talk to mr. Truax or to the RHOMBUS guy. Those SSTOs I can believe in, ones with wings and landing gear (repeat with me, wasted mass) I cant.
 
VWhat about salvaging Shuttle-C's SSME in orbit ?

there several ideas and plans

include astronaut EVA to recover SSME from Shuttle C
also in 1993 Option-C

mostly was is a ballistic recover module for 3 x SSME

by the way wat was left over from J-2 and M-1 engine Programm in 1990s?
was there some this hardware usable for Shuttle-C ?

(in Stephen Baxter "Titan" NASA mission salvage old Apollo hardware for the last manned Mission)
 

Archibald

Banned
If pigs have wings, they could fly...

Someone hasn't read my timeline, thus he has not understand that I TRY TO STAY CLOSE FROM OTL (not reinventing the wheel :mad:)

http://forum.nasaspaceflight.com/index.php?action=dlattach;topic=13040.0;attach=106506

This article just surfaced on the NASA board. It discuss all project based on Skylab B.
The thread itself is interesting to read

http://forum.nasaspaceflight.com/index.php?topic=13040.30

This part sounds interesting...

InternationalSkylab.jpg
 
Someone hasn't read my timeline, thus he has not understand that I TRY TO STAY CLOSE FROM OTL (not reinventing the wheel )

if thats me, I Sorry !

back to note
This part sounds interesting...

this "another S-IVB stage" dockt on Skylab B in 1978
sound like Advance Advanced Station aka Skylab C study
http://www.astronautix.com/craft/sivation.htm

there was also some thing about a artificial gravity experiment on Skylab B

at NASA ntrs i Found this ARTIFICIAL GRAVITY EXPERIMENT DEFINITION STUDY 11,39 MB big
http://hdl.handle.net/2060/19850068089

see
PDF page 160 Skylab with SEM (Systems Experments Module) instead ATM
PDF page 162 Skylab with EAM (Extended Airlock Module) aka MDA instead ATM
 

Archibald

Banned
Nope, that's not you, don't worry!! :D


The problem with the article (and the extract I posted) is that it doesn't deal about difference in atmospheres between Skylab and the shuttle...

Yes, they thought about sendng skylab into artificial gravity. They were pics of its in the "advanced Skylab" pdf you posted a while back in another thread.
I had never understood why they planned four more Skylabs when there was only two saturns to launch them. In fact they also wanted to cancell everything from Apollo 15 to 17, hence more Saturns...
 
Nope, that's not you, don't worry!! :D
I had never understood why they planned four more Skylabs when there was only two saturns to launch them. In fact they also wanted to cancell everything from Apollo 15 to 17, hence more Saturns...

there were 2 Saturn V almost complete back in 1968 SA-516 and SA-517
tanks, interstage, engine neede only assembly but in august 1968 SA-516 and SA-517 are chanceld

SA-516 & SA-517 were for Apollo 20 Mission and one Backup
there also the chanceld second production run of Saturn V (7 units)

if they hab build them, we had launcher for alots Skylab

another alternative was Shuttle booster with a Saturn-II upperstage
like Saturn V designs for reusable boosters, for the Space Shuttle
but only $2 milion more was needet for that system but NASA don't had the money
so they take today Shuttle concept

or Shuttle-C like i proposed it :D
by the way a Shuttle-C need only 7xJ-2
leftover J-2 from SA-516 & SA-517 = 10 Engines
 

Archibald

Banned
The problem I currently face writting this timeline is US duration records.

The soviets spent 237 days in their Salyut can on the year 1984.

Don't know if NASA would try to break those records... or privilegiate "scientist value" of mission (treating soviet long stays as stunts).

By the way, the role of shuttle changed. It has no longer to be a money-maker truck carrying satellites at bargain prices.

So the agency can reduce flight rates to the (OTL) post-Challenger level. I mean, eight flight a year.

Hence, I think that Challenger could be butterfly away...

back in 1981 OTL, NASA administrator already reduced flight rate from the planned 50-60 to 24. Even that proved impossible to achieve.
A space station would be a way of lowering flight rate futhermore...

No one will complains of the Shuttle losing its commercial role.

USAF and commercial operators will keep their expendable rockets.
Ariane will suffer more in consequence
 

Archibald

Banned
wonderfull TL !

here some note on space hardware lifetime

MIR space station lifetime 15 year (deorbit for ISS)
ISS space station lifetime 19 year (start 1998 - deorbit 2017)

so Skylab B launch in 1974 can be used until 1989-1994 !

so wat after Skylab B ?
one is build Space Station Freedom at Skylab B
http://en.wikipedia.org/wiki/Space_Station_Freedom

and get same ISS problems :(

but there better way !
build Skylab C and launch as shuttle C :D

in 1993 this was Option C in US space Station plans

http://www.astronautix.com/craft/spas1993.htm
http://www.astronautix.com/graphics/d/diag93c1.gif
http://www.astronautix.com/graphics/o/optionc3.jpg
http://www.astronautix.com/graphics/d/diag93c2.gif

This "option C" is great!

Most importantly, it gave me an estimation of the cost of an upgraded Skylab.
Thank you again for the link, very useful.
 
The problem I currently face writting this timeline is US duration records.

The soviets spent 237 days in their Salyut can on the year 1984.

Don't know if NASA would try to break those records... or privilegiate "scientist value" of mission (treating soviet long stays as stunts).

under Reagan ? oh yes ! we have to beat the Sovjets....
so we put a Astronaut for more than 300 days in Skylab B

By the way, the role of shuttle changed. It has no longer to be a money-maker truck carrying satellites at bargain prices.

So the agency can reduce flight rates to the (OTL) post-Challenger level. I mean, eight flight a year.

Hence, I think that Challenger could be butterfly away...

back in 1981 OTL, NASA administrator already reduced flight rate from the planned 50-60 to 24. Even that proved impossible to achieve.
A space station would be a way of lowering flight rate futhermore...

There will be "malfunction" of Shuttle Challenger or Columbia
Dam was Stephen Baxter close on Columbia in his book "TITAN"

Lost Shuttle brings the Crew on Skylab in trubble
"Sorry guy, you have to stay for next 2 Years in Orbit"
Resupply by Automatic Craft (like ATV) the Crew
Re activation of Apollo Hardware and launch it with Titan IIIC and save the Crew
or worst the Sovjet come to rescue with TKS !

here is interesting question:
Wat happen if a Shuttle get crash ?
Skylab Crew is resuppy by a "ATV", then rescue by Apollo leftover Hardware
some US Politicians will wonder: do we need a Shuttle ?
would be ironic: a fast Kill of Space Shuttle, for a post Apollo Capsul to save a Apollo Space Station


No one will complains of the Shuttle losing its commercial role.

USAF and commercial operators will keep their expendable rockets.
Ariane will suffer more in consequence

ESA in this timeline has difficulties in 1973
Germany demand more money from ESA to make the Spacelab modifcation for Skylab B
in France President Valéry Giscard d’Estaing try to kill the Ariane rocket program
because of the cost.
Higher cost for Spacelab is that wat he need for justification to chancel the Ariane.

little note on Sovjet:
with Skylab B in Orbit, the Sovjet will try surpass USA
and start to build from Salut & TKS Module a Orbital complex called MIR
Mir was authorized as part of the third generation of Soviet space systems in February 17, 1976
supply by TKS space craft http://en.wikipedia.org/wiki/TKS_spacecraft

only thats in this Timeline MIR get bigger than in OTL
 

Archibald

Banned
I've found more details on interim Apollo flights (1974 - 1978)

http://beyondapollo.blogspot.com/2009/04/post-skylab-missions-study-1971.html

This article features some speculative dates for flying the remaining CSMs in the 1974-76 era.

August 1974 would see a 15-day Earth Survey mission using a J-type CSM (designated CSM 115, it was originally intended for Apollo 19).

(ASTP is the second mission, happened in 1975)

NASA would fly a second Earth Survey mission similar to the first in September 1975 using CSM 115A (originally slated for Apollo 20), which was incomplete and in storage at North American Rockwell's Downey plant in California. The 1975 mission would help to ensure complete coverage in the event that clouds obscured parts of the U.S. during the 1974 mission.

The fourth mission, listed as "undefined," would launch in July 1976, in time for the U.S. Bicentennial. It would use CSM 119, the back-up CSM for the three Skylab A missions
 

Archibald

Banned
I should upgrade this TL someday.
Something I didn't realized when I wrote this many years ago is that the fate of Skylab A could have extremely interesting consequences down the line.
Because no manned Apollo reboosted it, Skylab A will fall back to Earth much sooner than per OTL, perhaps in 1976.
It will be an uncontrolled reentry with the same issues, although much earlier.
Now if Skylab A reenter as controversially as per OTL, Congress will inevitably ask - what about Skylab B now in orbit ? uncontrolled reentry, too ? I can imagine how big a scandal that might cause.
Thus,
NASA might be forced to properly desorbit Skylab B. But, since the shuttle won't be ready in time, the space agency will have to build a robotic tug. My favourite is the Lockheed Agena.
Now, follow my reasonning. If Skylab B is in good shape, why desorbit it ? the tug could reboost it. And since Skylab B lifted off 15 months later, it might last long enough to wait for Columbia STS-2 in November 1981.

Now, if Skylab B gots salvaged, everything change.
- In Congress view, NASA already has a space station in orbit, so say goodbye to Freedom - it won't be funded in 1984.

- Meanwhile the shuttle ferries only four astronauts to Skylab B - they all seat on the upper deck, on SR-71 ejector seats. that close much of the "SRB gap" - astronauts can eject from 0 to 90 seconds (Mach 3) while the SRBs are jettisoned 120 seconds into the flight.

- with a space station to go the shuttle no longer needs to launch everything * satellites and planetary probes included. This in turn butterflies STS-51L (NASA doesn't launch that day because of unflexible planetary windows).

Overall, the early history of the space shuttle is much more positive - even if the vehicle is still flawed.
This can led to a more interesting Space Exploration Initiative in 1989 - who knows, may be a successfull return to the Moon by the end of the century using the Shuttle C.
 
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