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From: Greensboro, NC USA
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posted 01-09-2012 09:46 AM               

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I was wondering what might have happened had the SL-2 crew not been able to save Skylab, or had the workshop suffered a more catastrophic failure on launch. The US had Skylab B (which eventually ended up in the Smithsonian), but no other Saturn V's that were launch-ready. I know that Skylab B had been considered as an adjunct to the ASTP mission - the first international space station - but NASA didn't have the funding to fly it.

Had Skylab A failed, I doubt there would have been funds or willpower to launch the backup. But what about the Saturn IB's and CSMs that would have taken the subsequent Skylab mission crews to orbit? I wonder if NASA would have found another mission for them, or if they would have been mothballed as well.

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From: Staten Island, NY
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posted 01-09-2012 10:58 AM               

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Jonathan, I guess there would be less autographs to collect.

Seriously, I'm sure Congress would have come up with the money (well, I like to think so).

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Posts: 162
From: Athens, GA
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posted 01-09-2012 04:45 PM            

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NASA did, in fact, have two flight-ready Saturn Vs available if Skylab had failed or if it was not able to be salvaged by the first crew (as it was).

NASA had SA-514 and 515 available to launch Skylab B had the first one failed.

Congress likely, but not certainly, would have funded the replacement had it come to it.

The saga of NASA's attempts to fly Skylab B can be found in Google Docs by googling "Frieling and Skylab B" to access my article on same from Quest magazine, late '90s.

Posts: 2272
From: Bellevue, NE, USA
Registered: Aug 2007

posted 01-09-2012 09:24 PM               

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Indeed, NASA always likes to have a hardware backup available for just about everything, so they had a Saturn potentially at their disposal for it (modules from it ended up as part of the Saturns on display at JSC and KSC). While Skylab got its Saturn transferred from the lunar program after Apollo 11, the cancellation of Apollos 18 and 19 were due to a conscious decision to fly the lab instead of two more missions to the moon. NASA had the money to do one or the other, but not both. So they figured a new space program with four launches (one lab and three manned missions) provided more bang for their buck than two more missions to the moon and more lunar samples.

Since NASA had the hardware, the money needed to fly Skylab-B would have involved the man hours and preparation required to transport the stages to the cape and get them ready on the launch pad (and post launch refurbishment to the pad of course) and of course outfitting it with more experiments and food (assuming it would fly duplicates of what had flown on Skylab-A). Skylab-B naturally would have required modifications to its micro-meteoroid heat shield as that was the culprit for the damage to Skylab-A, so funding would have been needed for that item as well.

As for ASTP, I don't believe that mission timetable would have been a factor in a Skylab-B project. Congress in fact urged NASA to come up with a backup plan for ASTP as they felt the Soviets might conveniently find some way to bow out at the last minute. This is why the Apollo craft and docking module both were packed with science experiments. Some of the experiments were joint ones to be conducted with the Soviets. But a lot of them were stand alone and could be performed whether or not the docking mission took place.

Only factor on the Skylab side that might have affected ASTP would have been if the Skylab rescue CSM were needed for a mission (such as during SL-3's thruster failures) as that CSM was also designated the ASTP backup module.

I believe if the need came up, Skylab-B would have flown as one figures maybe an 18 month to 2 year delay in the program (where ASTP would have been). By that time, the Soviets would have successfully flown Salyut 3 and 4 (after losing three other Salyuts due to launch and on-orbit failures) and members in Congress might have considered it a loss of prestige to have the Soviets successfully flying three stations when the Americans failed in getting one off the pad (Senator Proxmire not withstanding).

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From: Bethpage, N.Y.
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posted 01-12-2012 12:01 PM               

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My guess is that given the political climate of the time and the "leadership" from the White House, Skylab B never would have flown.

The shuttle would have been re-examined too, remember it didn't pass by many votes in the Congress to begin with.

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posted 01-20-2012 11:31 AM            

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quote:

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Originally posted by Paul78zephyr:
If Skylab had been deemed too damaged to be used when would it have de-orbited?

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It is true that Skylab had no delta-v capability, thus it was unable to raise its orbit.

However, the last crew boosted Skylab's orbit with the RCS thrusters on the Service Module.

At the time, NASA thought this boost gave Skylab another "five to eight years" according to the official NASA history of Skylab. That proved to be optimistic.

But, bottom line: Skylab would certainly have reentered sooner than it did (July 11, 1979) without that re-boost from the final crew.

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posted 01-21-2012 03:27 PM            

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Given the fact that the Saturn V's S-II stage entered into the same orbit as did Skylab and itself reentered in January 1975 — that has to be the answer.

So an unboosted Skylab would have only stayed in orbit from May of '73 until January of '75.

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posted 01-21-2012 06:20 PM            

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While I grant you they were not identical, an S-II stage and Skylab (essentially an S-IVB stage) were close enough that their orbital lifetimes would not have significantly have differed if Skylab had been left in its original orbit in the absence of the reboost.

So for the sake of this hypothetical – when would Skylab have reentered without the re-boost from the last crew – the difference could not have been all that divergent.

A month or more? Two or three? Maybe. But certainly not years like July 11, 1979.