February 8, 1974: The final Skylab crew in their Apollo pulls away from the space station, concluding the flight program.

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The wake up call comes at 9:40 p.m. Eastern time (Feb.7), the final wake up of the Skylab program.  We will work the night toward a splashdown tomorrow morning, February 8, 1974.  We are the crew of the third Skylab mission, launch 84 days ago on Nov. 16.  We are Jerry Carr, commander; Bill Pogue, pilot; and Ed Gibson, science pilot.  We now hold every spaceflight duration record there is.

Go back to January 17.  That’s when we were given the go to extend our flight, originally planned for 56 days, to 12 full weeks.  We’d really hit our stride at that point.  So had Mission Control, all of us working much more smoothly and efficiently than at the beginning.  The first month had felt like, frankly, hell — with long work days that never seemed to end, never a breather.

By mid-January, the only question was, would Skylab hold up?  We were spending increasing time on upkeep and repairs.  Our main concern centered on the Control Moment Gyros (CMGs).  Skylab housed three big gyroscopes which served as attitude control, holding it in position, reducing the need to fire jets.  CMG #1 had failed.   We could control the station with two gyros.  But if a second should fail, we’d only have about five days of attitude control fuel to maintain position.

On January 23, CMG #2 goes into “distress,” slowed down before regaining normal operating spin.  We have to cancel maneuvers for data takes by our Earth Resources Experiment Package (EREP).  

By January 28, the pace is picking toward the mission’s denouement, our return eleven days away.  Our work with our solar observatory, the Apollo Telescope Mount (ATM), is slowing, yet the ground is filling every square of time with last-minute tests and photos.  And we’re furiously trying to wrap up our work with the Earth Resources Experiment Package, hampered by damn lousy weather over target areas.  

CMG #2 continues to hang in there, but again went in and out of distress on Feb 1.  At that point, we were just praying that it holds until our mission ends in a week.  Despite all the stresses of this long mission, we’re hanging in there, too, as a team.  Amazing how little friction flew between us.  

On the same day, we make our final passes observing the ground with our EREP.  Despite being hindered by cloudy conditions at times, as well as the gyro problems, we’ve completed 45 ground sweeps with the suite of cameras and sensors.

On Feb. 2, we enter the Apollo Command Module and check it out for our return.  And in turn, this forms a check on ourselves.  After so long in space, we’ve lost a bit of our touch for the Command Module systems.  We also prepare for our final spacewalk on the next day, to be conducted by Jerry and Ed.  It should be a routine EVA, focusing on retrieval of the film cassettes from the six solar telescope atop the ATM tower.

The spacewalk turns out far more taxing than we anticipated, filled with last-second tasks.  Indeed, we rank it as our most fatiguing spacewalk.  In retrieving the big film cassettes, we test a “clothesline” transfer device never used on any of the flights as it’d proved easier just to carry the cassettes down the tower.  We find the line works well, but it snags on Ed’s suit hoses, pulling out the connection for his coolant water.  Which he quickly reattaches.

We conduct an experiment to detect particles floating outside the station, photograph the upper atmosphere, retrieve several materials samples that had been left out to see how they “weather” in the harsh environment of orbit.  Our timeline keeps shifting around with these tasks.  Ed grumbles, “I thought I knew what we were to be doing out here, but I guess I don’t.”

We take what moments we can to look around.  We’ll never be here again, and no one will ever occupy this station as we have, even if the Space Shuttle makes a brief visit.  We attach an array of materials samples for a visiting Shuttle to retrieve, another investigation into the effects of long term orbital exposure.

And it ends after 5 hr. 19 min., ends with the tips of our fingers sore from pressing against the gloves.  Yes, a most fatiguing spacewalk, yet we cannot rest, only five days left.  The next day we begin packing up the Apollo Command Module with the bulk of the items we are returning, such as film, including 75,000 photos of Comet Kohoutek, and 100,000 ft. of magnetic tape filled with data.  We pack those Command Module lockers tight, so tight we have to shoulder the lids closed like you might sit on a suitcase to get it to latch shut.  And we’re chasing time — items not where they’re supposed to be.  A hell of a day, for sure.  

On Feb. 6, We feel we’re over the hump.  We get the Command module shipshape.  We’re not rushed like the day before.  We fire the Apollo’s thrusters to trim and raise the station’s orbit by 7 mi..  That should add a couple years to it’s lifetime, as the earth’s atmosphere, rarefied at this 270-mi. altitude but present still, gradually pulls Skylab down.  With that, the experts now estimate Skylab should remain in orbit 5-8 years.

The next day, we begin deactivating Skylab, shutting down systems, slowly putting her to sleep.  We conduct a microbiology survey — taking swabs of various surfaces and placing them in vials.  The samples will show what kinds of bacteria have found a home during the nine months of Skylab’s life.

We put items away, want to leave a tidy station behind. It’s a short day, as we go to bed 2 hrs. early to set up an early morning, our last aboard Skylab.

February 8, 1973 — the end of an era

We’re out of the box and quickly to work.  Jerry floats into the Apollo, his time inside the station over.  In the next few hours, he powers up the Command Module and conducts systems checks.

Back in the station, we perform the final close-out.  We switch control of the Apollo Telescope mount to the ground.  Turn off lights and the last systems.  Bill enters the Apollo, leaving Ed to perform the final tasks.  And then he moves toward the Apollo, closing the station’s hatches behind him.  At the Apollo hatch, he disconnects umbilicals running into the Command Module.  Leaves them in the Multiple Docking Adapter, along with a “time capsule” of various items in a bag, such a film and magnetic tape.  The hope is that in a few years a Shuttle crew will retrieve the bag to see how the items had degraded over time.

The hatch is closed — 3:30 a.m. Eastern time — for the final time.  Jerry tells Houston that he left a key under the front-door mat.

At hatch closing, we still have several hours before undocking.  Finally we’re in our couches, strapped in and ready.  Capcom Bob Crippen radios, “The party’s over, time to quit the fun and come home . . .  Looks like a good day for you guys to come home. ”  Crip reports fairly calm seas in the recovery area.

At 7:22 a.m. Eastern time, we get the formal word, we’re go for undocking.  Crippen calls, “Say goodbye for us.  She’s been a good bird.”

And 6 min. after receiving the go, we unlatch and pull back.  Then we conduct a fly-around inspection of the station.  We note the discoloration of the sunshade erected by the second crew.  It’s become two shades of brown, one dark and the other a lighter tan.  And we have words for crew who put it there:  “You can tell Al Bean and the guys they did a great job putting that sail up.” 

Ed comments, “I tell you, this vehicle sure looks like it’s been worked over.” 

Gazing at empty station, we say, “It’s been a good home, Crip.”

He says, “You guys occupied it long enough.  Everything’s looking good here.  You are got for the sep. maneuver.”   Our 25-min. of Skylab-gazing is over; we make the separation burn.  Jerry watches the station for as long as he can.  “There it is, fading into sunset.”

And after another 25 min., once were at a distance, we make the first of two burns to bring us home.  It’s called a shaping maneuver, a burn of our big Service Propulsion System (SPS) engine at 8:33 a.m. Eastern for just 12.4 sec.  Our return is now two hours away.

At 10:36 a.m. Eastern, we nudge ourselves out of orbit with a 7.97 sec. burn of our SPS engine.

We are headed for a splashdown 180 mi. southwest of San Diego in 41 min.  When we touch the Pacific waters, our voyage of 34.5 million miles through 84 days, 1 hr. 15 min. and 31 sec. will be over.  And with it ends the first era of U.S. spaceflight.