Fifty years ago: Apollo’s last lunar liftoff

Dec. 14, 1972: The Lunar Module Challenger at the moment of ignition and liftoff, ending Apollo’s last exploration of the lunar surface.

*****

Take a good look out the windows, at all the footprints and Rover tracks darkening the lunar soil, going off in all directions, crisscrossing the ALSEP site dotted with experiment packages, disappearing left and right towards the mountains.  It’s all beyond our reach once more, here on December 14.  It’s about 13 hrs. since we made made our last tracks on the lunar surface.  We wake less than 7 hrs. from lunar liftoff, on this, December 14, 1972.

Are we filled with nostalgia and melancholy?  No, we’re relaxed, singing to Capcom Gordon Fullerton, “Good morning to you; good morning, dear Gordy, good morning.”

And you Jack, have written a poem in the style of “The Night Before Christmas,” which you read to Houston.  It begins, “It’s the week before Christmas.  And al through the LM, not a commander was stirring.  Not even Cernan.”

After a meal, we suit up and have one last task — equipment jettison, to reduce weight — as weight is fuel, you might say.  Even lightened, we’ll have just enough fuel to reach orbit.  So about 3 hrs. before liftoff, which is scheduled for 5:55 p.m. EST., we depressurize and open the hatch.  We jettison bags of trash and unwanted items, simply kicking them out the hatch with enough force that they go over the side and to the surface.

“Here you go, Santa Claus.”  I kick a bag out and down onto the surface it tumbles, a “Santa Claus bag.”

“Another bag of goodies,” you call.

I give it a perfect kick, a football field goal.

“Nice, beautifully done!” you say.

With the hatch open, I turn and pretend I’m getting out for another moonwalk.

“Don’t even think of it.”

It’s impossible, of course, since we’ve also discarded our trusty “PLSS” backpacks.  We close the hatch — it’s only been open a minute.   A short EVA, I joke.

“Boy, is it easy to get around in here without a PLSS on,” I say.

We still have plenty of work to do readying systems and checking everything.  Ten minutes before liftoff, we pressurize the Ascent Propulsion System, that’s the engine that must work to take us to orbit.

“Houston, Challenger is go for lift-off. We’re at [T-minus] 7:54 and counting.”

Fullerton say, “Roger, Challenger. You’re go for lift-off.”

We run down the checklist of what will happen.  “Okay. At 10 sec. I’ll hit the Abort Stage, followed by the Engine Arm to Ascent.  You get the Pro.”  That is, you will press the button that tells the computer to proceed with the engine firing.  

Fullerton radios, “Everything looks great down here.”

One minute to go.  “Take your final look at the valley of Taurus-Littrow, except from orbit,” I say.   And as the seconds fall away, I tell you, “OK, Jack, let’s get this mutha out of here.”

“Abort stage . . . Engine arm in Ascent.”

“Ignition.”  It’s precisely 5:54 and 37 sec. p.m. EST

We hear a burst of static from the radio, as Challenger rises swiftly, our last look at our base camp showing a wave of dust and gold insulation roiling across the surface.

“We’re on our way, Houston,” I call.  We should achieve orbit in less than seven-and-a-half minutes.

“Rates are good,” you say.   Just 9 sec. after liftoff, Challenger pitches over so that the engine is firing parallel to the surface, which is the most efficient orientation.  We are facing the surface and watch our valley shrink and slide from view, taking our tracks with it.

We experience communications problems.  Switch antennas and lock on, I report, “OK, 4 min. Challenger’s go. We’re through 37K [37,000 ft.].”

“Roger, Challenger. You’re looking good here.”

Five minutes.  “PGNS and AGS are looking good.”  Those are our two guidance systems, primary and “abort” backup.  It’s always good when PGNS and AGS agree.

Fullerton says, “Challenger. Your trajectory is right on the money. Both systems are go.”

Approaching the end of the burn.  I say, “Let’s double-check everything now.”

You say, “AGS and PGNS are right together.”  About a minute to go . . .

Seconds later, I call, “Seven minutes, Houston. And we’re passing 59K.”

You call, “OK, stand by for shutdown . . .  Shutdown!”

After an ascent burn of 7 min. 21 sec., we’re back in orbit, an elliptical one of  of 57.5 mi. by 10.5 mi.  The chase is on to rendezvous, in just one orbit, with Ron Evans in the command ship, America.  And 47 min. after achieving orbit, we’re 37 miles behind  and 17 mi. below Ron and make a burn called Terminal Phase Initiation.  It lasts just 3.2 sec. and boosts us into catch-up orbit.  Fifteen minutes later we perform the first of four braking maneuvers that match America’s 71-mi. circular orbit.  Those burns set us up for final approach.

We hit all the gates and come in very slowly to stationkeeping position, formation flying around the command ship.  “Good to see you,” I radio Ron.

“Good to have you all back up here.”

“It’s been a good trip!”

“That Challenger is a beautiful vehicle.”

“You betcha.”

We rotate to present our docking drogue to America.  Ron closes in slowly.  Too slowly, it turns out.  We make contact cleanly, but the three capture latches in the nose of his docking probe fail to engage.  He backs out 3 ft. and comes in a bit faster.  

Capture, Houston!  “OK, that’s a good one,” Ron calls.

We dock at 7:58 p.m. EST, just 2 hr. 16 min. since we left the lunar surface.  A half hour later we begin transferring our cargo of lunar samples, which will weigh out at 243 lbs., and everything else we want to take back with us.  We’re careful to keep as much dust as possible out of America — the air flow into the LM keeps most of the floating dust contained.  The transfer takes an hour, and 25 min. later, we take one fond last look around. . .  It’s time. 

Gordon Fullerton calls, “Challenger, you’re go for close out.”

“OK, Houston, Challenger is going off the air.”

“Pleasure talking to you these past few days.” 

I reply, “It seems like an unfitting finish to a super bird, but it has one more job to do.”  That job will  be to descend to the moon a second time, on her own, in a crash near our valley of Taurus Littrow.  The impact will recorded by our ALSEP surface seismometer, sounding out the nature of subsurface. 

We swim up to the tunnel to America.  It’s only been about two-and-a-half hours since we docked.  We secure the hatches and about 45 min. later, cast Challenger loose.  

And fire America’s thrusters to move away.

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