50 years ago: Apollo 14 lands on the moon

The Lunar Module Antares at Fra Mauro

*

            It’s February 5, 1971 — and it’s going to be a long one for us, the crew of Apollo 14 — landing on the moon at the rugged Fra Mauro site and then five hours later, our first moonwalk, which could last more than 4.5 hours.

            You could call our outbound trip restful, except for the natural tension of anticipation — of all that must go right.  And might go wrong.   On the first full day of flight, February 1, our focus centered the finicky docking mechanism that had nearly ruined the mission.  We inspected for signs of foreign material that might have caused the problems.  None. We inspected the mechanism for signs of damage.  None. We operated it in the cabin — and even with Al Shepard in the Lunar Module (LM) we’ve named Antares, watching how the latches engaged the LM drogue.  The thing operated smoothly.  By the end of the day, we’re given a go for Fra Mauro.

            On February 4, we enter lunar orbit, and after two circuits (4.5 hours), perform a first, one that had been planned for Apollo 13 — and early DOI (Descent Orbit Initiation, burn to swoop into low orbit with the engine of our command ship, and enter the staging orbit for the landing.  On previous flights, this maneuver was done a few hours before landing by the Lunar Module.  

            We burn our Service Module’s main engine for precisely 20.6 seconds.  If the burn is just six-tenths of a second too long, we’d be headed for a crash on the surface, necessitating a quick “bail-out” maneuver.  But Houston calls that we’re right on the money.  “Good show,” we call.

            By using the command ship to perform the DOI, we save the Lunar Module’s fuel, enough for 2.5 minutes of hover time near the surface.  In addition, entering low orbit a day early provides plenty of time both to view the site at low altitude and give the precise tracking that will be used to refine our navigation for a pinpoint landing.

            From our close orbit, Al Shepherd calls, “It’s really a wild place up here.”

            We observe, “This country down here is really rugged at this altitude.  That’s the most stark, desolate-looking piece of country I’ve ever seen.”

            Al Shepard is confident. “I think we can make it down from there tomorrow.”

            Our Command Module Pilot, Stu Roosa, is have a problem — with the large format “Hycon” lunar topographical camera, a big beast of a camera, installed in the hatch window. He hears strange clicking noises when it runs.  Changing film magazines doesn’t help.  The camera has failed.  Instead, it will photograph the Apollo 16 site and other surface areas with our old standby, the Hasselblad camera, with a telephoto lens.

*

            It’s now February 5, landing day.  We enter the LM, power up and undock — all by the book, less than five hours until landing.  But that’s when it happens.   A light flashes on our panel, one of our two guidance systems, the Abort Guidance System, is signally an abort — as would occur during landing.  But we’re still safely in orbit.

            What’s going on? As any home hobbyist would do, we rap on the panel.  The light goes out.  Then comes back on.  We rap again — it blinks off.  Obviously there is a short in the abort system — perhaps a bit of loose solder floating in the circuit.  Just as obviously, we can’t land with it — the short could trigger an erroneous abort, sending the ascent stage/crew cabin blasting away from the box-like descent stage with its landing legs.

            Can a patch be programmed into the LM computer to tell it to ignore the false signal?   Down on Earth the call quickly goes to MIT’s Draper Lab where the computer and its programs were developed.  We don’t know his name until after the mission — Donald E. Eyles.  He is a 27-year-old programmer, with the Draper Lab since 1966, to whom the task falls to quickly devise the patch.  His mind is fluent in the language of numbers — computer code.  On the clock, he comes up with a fix involving 26 sets of five-digit instructions.  These set up a manual override, meaning an actual abort will have to be keyed in by the crew.

            The strings of numbers are read up to us, then called out by Al Shepard, and entered into the computer by our Lunar Module Pilot, Ed Mitchell, and read back to verify, a painstaking process.  And we’re now less than a half hour from PDI, Powered Descent Initiation, the start of the 12-minute descent to the surface.  At the same time, the simulator at the Kennedy Space Center is running the program to verify that it works.

            We’re just five minutes to PDI, and entering the final numbers:  “One-zero one”

            “One-zero-one.”

            “Ten-ten entered. One-seven entered.”  That’s it, four minutes to PDO.  “OK, Houston — do you see it?”

            “Roger, Antares.”

            Shepard calls, “Antares is standing by for a PDI go.”

            At nearly the same time the Kennedy simulator verifies the patch will work.

            There is a pause. Then Capcom Fred Haise, the Apollo 13 Lunar Module Pilot who’d lost his chance at this landing, replies “And Antares, Houston — you’re go for Fra Mauro.”

            We reply, “Roger, go, Fredo, thank you.  You did a good job down there.  Beautiful.”

            Tense?  Na — just the sort of problem we train for in the simulations!

            The engine ignites, throttles up.  The computer corrects a half-mile error in our landing point.  “OK, almost back on track.”  We’re go at three minutes.   “OK — throttle converging.  Looks nice.”

            “We should be getting landing radar.”  It should have switched on before now.  

            Ed Mitchell implores it. “Come radar — get a lock.”  Mission rules dictate we must have radar in order to land.

            “Come on, radar.”   We’re at about 4 mi. altitude.

            Houston calls, “Go at five.”  But we won’t be “go” for long without that radar.  If we don’t get it?   . . . To hell with mission rules.  You know Al Shepard — he’ll try to land the thing without it.

            Houston calls, “Antares, we’d like you to cycle the landing radar breakers.”

            “OK — cycled.”

            Again Ed Mitchell breaths, “Come on.”

            The radar kicks to life. Shepard calls, “How’s it look, Houston?”

            “OK, we’d like you to accept the radar.”

            That was close. Coming up on 6 min. 40 sec. into the burn — throttle down.

            We’re at the point called “High Gate.”  We’ve been flying with the engine forward for maximum braking.  “OK, there’s pitch over.”   We tilt vertical, giving us our first look at the landing site. “There’s Cone Crater.  There it is!  Right on the money,” Shepard calls.  The crater, the target for our second moonwalk, sits to our right, elevated against the side of a long ridge.

            We slide toward a spot on the undulating floor beside it.  It looks rougher than we expected.

Houston calls, “Antares, Houston, you’re go for landing.”

            Mitchell gives Shepard the numbers, altitude first.  “Two-thousand, 50 ft. per sec.  A little bit fast, but not bad. . . .

            Shepard observes, “OK, the best spot is a little south of track, halfway between Triplet and Doublet.”   Those are sets of craters.

            Mitchell calls, “OK, Al.  You’re through 550 ft., 16 ft. per sec.  Five hundred feet.  Looks good. . .  You’re fuel is good at 10 percent.”

            Shepard calls, “Let’s take over . . . Manual mode.”   He’s flying the ship now.  We fly over one our landmarks, a three craters called Triplet, directly over the north crater of the three, its bottom deep in shadow.   Slowing — we want to land between Triplet and another landmark, two craters called Doublet.    Shepard flies her in, looking for a smooth spot, speeds over one spot, hovers at 170 ft. altitude for a bit — still 7 percent fuel.  Mitchell calls, “Still at 170 ft.  You’re barely crossing north of Triplet.”  Shepard slowly brings her down toward the dust.  

            “We’re in good shape,” Shepard says.  We’re at an altitude of just 40 ft.  . . . 30 ft. “Looking great.”  Twenty feet.  . . . Ten feet.  “Contact, Al”

            “Engine stop. Great, oh!”

            “We’re on the surface.”

            Indeed we are, right on the dot, just 87 feet from the planned bulls-eye, the most accurate landing of the Apollo program.  The landing took 1 min. 15 sec. longer than planned, as we hovered, with plenty of fuel, selecting the exact spot.  We’ve landed on a slope, the Lunar Module tilting eight degrees, well within tolerances. We’re in a low spot, in a kind of bowl, low ridges all around.

            Shepard says, “It’s a beautiful day to land at Fra Mauro.”   It’s exactly 9 years, 9 months since his short Mercury flight.   

*

            “Ed, we’d like you to put the relay switch on your panel to ‘on’ for about 20-30 sec. during which we’ll try to establish communications with Al.”

            “OK — on my mark we’ll go to relay on.  Three, two, one — Mark.

            “Antares, Antares, this is Houston — Do you read, Al?”

            A long day is getting longer.   We’re behind the timeline before our first steps on the moon.  Shepard’s suit communications system isn’t transmitting.  We waste 50 min.  Finally find the cause — a circuit breaker in the wrong position.

            Now we are ready for Fra Mauro, the foothills of the lunar highlands, which should prove more ancient that the Mare lava plains where Apollos 11 and 12 landed.  We plan to stay on the lunar surface 33.5 hours, make two moon walks of up to 4.75 hrs. each.  We may find rocks dating back 4.5 billion years to the formation of the moon. That will be the objective of the second moonwalk tomorrow — a climb of one mile to the rim of Cone Crater at the crown of a 400-ft. high hill where we will sample boulders excavated from its impact. Those samples could date from the moon’s original crust.  The view into the 250-ft. deep crater should be magnificent.  But on this first moonwalk, our main objective may appear more mundane yet is of primary importance:  Setting up the second Apollo Lunar Surface Experiment Package (ALSEP), a suite of six experiments that return data on the moon for at least a year.

            “OK, starting out the door,” Al radios.  He backs out the hatch onto the “porch.”  He looks our over the lunar vista and says, “It certainly is a stark place here at Fra Mauro.  I think it’s made all the more stark by the fact that the sky is completely black.”

            “And we’re going to deploy the MESA.”  That’s the Modular Equipment Stowage Assembly at the side of the descent stage by the ladder. He pulls a lanyard and it swings open to expose the color TV camera that will share Fra Mauro with the world. “The MESA has released . . . Starting down the ladder.”

            Capcom Bruce McCandless says, “OK, Al.  Beautiful. We can see you coming down the ladders. Looks like you’re on the bottom step. And on the surface.  Not bad for an old man.”

            “OK — right you are.  Al is on the surface.  It’s been a long way, but we’re here.”

            He must be thinking back the years to his Mercury flight.  Later he will admit that looking out over the lunar surface, a tear came to his eye.  Maybe more than one.

            But to all signs, he’s all business.  “I can see the reason we have a tilt is because we landed on a slope.  The landing gear struts appear evenly depressed.”  And one footpad has sunk into the soft side of a small crater.

            He moves around, getting a feel for walking on the moon.  “I’m getting familiar with the surface.  The surface is so soft it comes all the way up to the top of the footpad . . .  OK, we’ll move on over take a look at . . . Cone Crater.   And it’s a very impressive sight. . .  We can see the boulders on the rim.  It looks like we have a good traverse route up to Cone.  I can see Cone Ridge going around to the north. It’s very apparent.”

            Eight minutes after Al’s first step, we join him on the surface.  We look up Cone crater and say, “It doesn’t appear like there’s going to be any trouble getting the MET up Cone Crater.”  

            MET is the Modularized Equipment Transporter, a two-wheeled pull cart that will carry our tools and samples, jokingly called “Shepard’s Rickshaw.”  He’s unstowing it now.

            We find the surface very fine grained, with just a scattering of rocks, indicating it is an ancient surface that has been pulverized into dust.  Yet it is a rough place, craters everywhere.  We move 25 ft. from the LM and take the contingency sample near a 5-ft. crater.  That’s so if we should suddenly have to depart, we’ll return with at least one sample. Most of this moonwalk will be devoted to other tasks rather than geology, although we hope to have time to take samples at Doublet Crater, near the site for the ALSEP array of experiments.

            For the first part of the EVA, we work near the LM, setting up an umbrella-like S-band antenna to improve communications.  Setting up a sun-shade like solar wind experiment that will trap particles from the sun.  And deploying the flag — we only take 5 min. for that.  We’re bounding around much more confidently than just 20 minutes ago.

            We off-load the ALSEP packages for a storage bay at the back of the LM, a task that takes 10 min. itself.  Now comes the tricky part — fueling the ALSEP’s power generator.  The generator’s thermoelectric power comes from the heat of an isotope of Plutonium-238 carried to the moon in a cask.  We must extract the fuel capsule and insert it in the finned RTG — Radioisotope Thermoelectric Generator.  Apollo 12, who deployed the first ALSEP package, encountered trouble when the fuel capsule became stuck in the cask.  We have improved extraction tools, and delicate operation goes smoothly.

            We’re on the timeline — or at worst, a few minutes behind — as we head out to the ALSEP site. We need to choose a smooth spot 400-600 ft. from the LM.  And that’s going to be hard — the landing site is much more undulating than we expected, ringed in ridges.  We go down one depression — the bottom deeper than it seemed and trudge up another ridge.

            We carry the experiments and associated hardware like a dumbbell in two packages at the ends of a pole. Shepard says, “Think there’s a level site fairly close to the south rim of Doublet.”  He pulls the MET cart along — says it’s very stable.  

             “We could spend the entire EVA within a hundred yards of the LM” — there’s so much to sample.  “Houston, this looks like brown talcum powder, it’s so fine, in most places.”

            Shepard calls, “There’s our spot” — as level as were going to get — “We’ll proceed with the deployment.”

            The ALSEP consists of five experiments linked by cables to a central station, two investigating the seismic nature of the moon and three detecting the stream of particles from the sun and the environment of the trace lunar atmosphere.  In addition we set up a laser retroreflector panel that will be used by lasers on earth to precisely measure distances to the moon the variations in that distance.

            We begin by deploying the central station which provides the power and transmits the experiment data to earth.  Ed Mitchell quickly reports, “I can see this is going to be a considerably slower process than I expected.”  We are already a half hour behind the timeline.

            We have trouble with one of the experiments — a stuck bolt.  They the experiment keeps falling over.   And our most time-intensive task is ahead, the active seismic experiment. For this, we set a line of three geophones at a distance of 10, 160 and 310 ft. from the central station.  Ed reports, “I’ve got my first geophone in the ground.  In the soft ground, they go in vertically without any problem, and they push right in.”

            At the same time, Al Shepard aligns the antenna of the central station.   Houston quickly reports, “And Al, for your information, they’re receiving a good signal.”

            Now comes the active part in active seismology.   We use a “thumper” which fires shotgun-like cartridges against a plate to vibrated against the soil.  The sonar-like vibrations provide information on the subsurface to a depth of 500 ft.         The Thumper has 21 charges, to be fired at 15-ft. intervals.  We must pause all activity for several seconds as the seismic waves rebound and are picked up by the geophones.  

            “Five, 4, 3, 2, 1 — Fire.  I didn’t feel anything, Houston.”

            We reset and try again. “Ok, we got it that time, Houston.”

            But several of the charges fail to fire at all.

            We’ve gained a 30-minute extension of the moonwalk, but are eating it up working with the ALSEP.  Our final task, arming a set of three mortars that will be fired remotely after we’ve left the moon to provide additional seismic data.

            We won’t have time to sample Doublet Crater.  Houston calls, “After arming the mortar, we’d like you to head back in the general direction of the LM, and selecting a suitable area en route, take the comprehensive sample and try to pick up a football-size rock on the way.”

            Heading home, about two-thirds of the way there, we pick a small area, and pick up surface rocks and a sample of the soil.  Shepard selects a couple rocks the size of small footballs, and tells Houston, “Al is starting back to the MESA.”

            Back at the LM, we still have more than a half hour of work stowing equipment and samples.  And dusting each other off, trying not to track as much of the the fine dust into Antares as possible.  An impossible task.  “Those overshoes are impossible.”

            Our voices slur with obvious signs of fatigue.  The moonwalk ends after a record length of 4 hr. 47 min. 50 sec.   We traveled 3,300 ft. and gathered 45.19 lbs. of samples. And at this point, we’ve been up for 20 hours.   

            And after a long day, alas, our “night” in the cramped, tilting LM will provide little rest. 

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