Moon Lander: How We Developed the Apollo Lunar Module (46 page)

Despite a valiant effort, Shepard and Mitchell did not reach the rim and gaze across the crater’s vastness. The lack of size reference and memorable landmarks, the sharply undulating surface and unfamiliar lighting conditions combined to make the ascent of Cone’s flanks seem like an outdoor hall of mirrors to the frustrated explorers. Mitchell went over to Shepard and showed him the map. “Look,” he said, breathing heavily, “let me show you something.… We’re down
here
. We’ve got to go
there
.”

They reached a level area, but the rim was still nowhere in sight. Mitchell again studied the map. “This big boulder, Al, that stands out bigger than anything else—we oughta be able to
see
it.”

“Okay, Ed and Al.” From Houston the firm voice of CapCom Fred Haise told them that time was up. They had used the half-hour extension that Mission Control had granted and still not found Cone Crater. In their stiff pressurized spacesuits, they were tired from the exertion of climbing uphill. It was later determined that during their return they were within sixty-five feet of Cone’s rim, which looked to them like just another of many false summits.

Despite not finding Cone’s rim, Apollo 14 was a major scientific success. The explorers broke all prior records for time on the Moon (one day, nine and a half hours), duration of moonwalks (nine hours, twenty minutes), and pounds of samples returned (94.4). They squeezed the most they could from Antares, the last of the basic LM designs to fly in Apollo. Subsequent missions would have the extended stay version of LM, capable of spending three days on the Moon, and carrying the Lunar Roving Vehicle.

Before reentering Antares, Shepard produced a golf club and balls, and standing in front of LM’s TV camera, he showed the world how far one could hit a golf ball on the Moon, in one-sixth gravity and without atmospheric drag.

“In my left hand,” he announced, “I have a little white pellet that’s familiar to millions of Americans …” On his third try he hit the ball solidly, lofting it up into the black sky and over the craters in slow motion.

“Miles and miles and miles!” Shepard chortled.
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Without that clumsy spacesuit he felt he could have put it into orbit.

While the crew was tidying up Antares’ cabin and eating, in SPAN I was working on a problem in the S-band steerable antenna, the LM’s primary communications link to Earth and the only means of high-bit-rate data transmission. The antenna was jittering around its locked-on position when transmissions were sent or received. We feared that it might break lock during ascent, depriving Mission Control of real-time data. NASA and Grumman engineers stopped the jitter by switching to an alternate ground uplink mode and recycling the antenna mode switch in the “auto” position. In any event, the omnidirectional antennas on LM would provide a voice link and low-bit-rate data.

Shepard and Mitchell proceeded through the LM prelaunch checkout. When they test-fired the reaction control system thrusters the exhaust breeze knocked over the erectable antenna that had been used to provide TV and high-bit-rate data and voice during the moonwalks. Liftoff took place on schedule, and the seven-minute ascent engine burn was flawless, placing Antares in the planned ascending rendezvous orbit.

Apollo 14 was the first mission to use a single orbit rendezvous technique, which completed rendezvous in two hours, instead of the two orbits used previously. The new technique worked perfectly and became the standard for subsequent missions. Near the end of rendezvous the LM’s abort guidance system, which was shadowing the primary guidance system as a backup, dropped out. Attempts to reset AGS by recycling switches and breakers in the cabin did not work, nor could Mitchell access AGS through its keyboard. Also, the LM master alarm did not announce the AGS failure as it should have. No effect on the mission, but another significant anomaly for our engineers to resolve before the next Apollo launch.
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Docking was perfect this time, using the normal procedure, and Shepard and Mitchell rejoined Roosa in Kitty Hawk, bringing their precious lunar samples with them. Antares’ ascent stage was jettisoned, and its engine was fired to cause it to hit the Moon midway between the Apollo 12 and 14 landing sites. The blast set off seismic ringing within the Moon that persisted for several hours on both sites’ ALSEP instruments. The return mission was routine, and in the Bethpage Mission Support Room I rejoiced in the happy smiles of the astronauts as they strode onto the carrier deck.

On Apollo 14, we in the back rooms had again helped save the mission. NASA Mission Control and its supporting contractors, put to the ultimate test in the incredible Apollo 13 rescue, were a practiced team that responded to problems with aplomb. The resourcefulness and adaptability of a combined man-machine operation in space and on the ground had been demonstrated many times over.

Although the total LM flight anomaly count on Apollo 14 was the lowest yet, the abort-stage switch failure was a serious defect that should have been detected before installation. The initial docking problem showed the need for
tighter control and verification of CM-LM interfaces. LM-8 reversed the favorable progression of LM quality and alerted us to improve quality control and take management actions to dispel complacency.

On the Moon’s surface, Shepard and Mitchell reached the limits of unaided “walking around” exploration. The Apollo program was ready for a higher level of capability, which the extended-duration missions would provide. Irrepressible Al Shepard and sober-sided Ed Mitchell had been a well-matched lunar exploration team. Now, what would their successors do with a sports car and two extra days to cruise the surface?

19

Great Explorations

Apollos 15, 16, and 17

Thanks to its foresight in upgrading the capability of the later Apollo missions, NASA was positioned to harvest a vast amount of scientific knowledge about the Moon and its origins. The extended-duration missions took advantage of increases in Saturn payload capability, eked out in incremental changes by Wernher von Braun’s engineers, and the weight savings we had swiped and scraped from the LM. Lunar stay time was increased to three days, more moonwalks were permitted, the scientific equipment package was expanded, and the lunar roving vehicle was added. The rover promised a new dimension in lunar exploration, as it greatly increased the astronauts’ mobility and endurance on the surface. Although the general public was becoming blasé about men on the Moon, scientists the world over anticipated the fruits of great explorations.

The Mountains of the Moon: Apollo 15

In June 1970 I returned to Bethpage from a year as a Sloan Fellow at MIT and plunged into the competition for the newly announced space shuttle, NASA’s major post-Apollo program. For the first time in eight years I was not assigned to the LM program, although in spirit I never left it and kept in touch as closely as my shuttle activities permitted. Having directed the engineering design of the extended duration LMs before leaving for MIT in mid-1969, I wanted to see how they had worked out. In August 1970 I attended the design review of LM-10, first of the extended-duration LMs designated for Apollo 15, where the new features were inspected and demonstrated. The redesigned descent stage had larger propellant, water, and oxygen tanks, two additional batteries, an expanded bay for scientific equipment, and a new quadrant bay to house the rover. The ascent-stage changes were minor: added lithium hydroxide
canisters, expanded stowage areas for lunar sample containers, food storage, and crew equipment, and accommodations for the redesigned spacesuits.

A demonstration with the completed LM-10 descent stage was held on the Spacecraft Assembly and Test final assembly floor, with astronauts Dave Scott and Jim Irwin participating. All the equipment that the crew would use in exploration was available, either as flight hardware or engineering prototypes. The demonstration was orchestrated by Grumman’s Will Bischoff, John Strakosch, and John Rigsby and their NASA engineering counterparts. Working with the engineers who designed the expanded Apollo lunar surface experiment package and the other scientific equipment and tools, they carefully stowed each item into custom designed holders within the bays, making minor adjustments where necessary for a perfect fit. After checking the latching and deployment mechanisms, the bay doors were closed as they would be at Kennedy Space Center prior to launch.

A team of Boeing engineers and technicians showed us the features of their prototype LRV. I marveled when they folded it up like a collapsible stage prop and nestled it securely within the bay. Because the rover was six times heavier than it would be on the Moon, our engineers improvised a counterweight system to ease the jolt when the bay door was opened.

When the descent stage was all buttoned up, Scott and Irwin opened each bay following the procedures they planned to use on the Moon. Surrounded by equipment engineers, they asked questions and gave their comments on each step of the deployment. Most spectacular was opening the rover’s bay: Scott and Irwin pulled two lanyards on either side of the bay, the door swung open, and the rover unfolded itself like an insect emerging from chrysalis, ending up angled downward in the bay with its wheels locked in position, ready to be rolled onto the surface. We applauded in appreciation of Boeing’s ingenious design.

I returned the following day to watch the final part of the demonstration. Overnight all the chits were dispositioned, final fit adjustments were made, and the descent stage was again closed up as for launch. Scott and Irwin would perform another deployment, but this time in pressurized spacesuits. A technician followed each of them, wheeling a portable cart supplying the suit with air and cooling. This was fascinating; even though they were on the familiar white tiles of the assembly floor, followed by a knot of people in white smocks, the sight of two spacesuited astronauts next to the gold and black foil clad descent stage stirred my imagination. As they bent over and deployed the ALSEP and the rover, I could visualize how they would look doing these same actions on the Moon, stirring up gray lunar dust with every step, surrounded by strange treeless plains and mountains surreally lit by dazzling sunlight or totally hidden in black shadows. This was as close as I would ever get to exploring the Moon, and I relished the fantasy.

I also attended LM-10’s customer acceptance readiness review board meeting
just before its delivery from Bethpage. NASA’s George Low presided, and the board’s review took only half a day, with relatively few problems. What an improvement from the early LMs! The review was held in the Plant 25 conference center, which was attractive, comfortable, and provided good acoustics and visuals. About two hundred NASA and Grumman engineers participated in three days of reviews and inspections. Chits were written and dispositioned with the usual rigor, but with less anxiety than I recalled from the early days. The LM program had grown and matured most satisfactorily.

I talked at length with Dave Scott and Jim Irwin. They were very pleased with the quality of LM-10 and excited about their mission. Scott told me the chosen landing site was beautiful and challenging. He hoped the TV images would convey some of its grandeur, because he knew their descriptions would be inadequate, even though they intended to share their sights and feelings with Earth as much as they could during the mission.

The extended-duration LMs greatly increased the scope and efficiency of lunar surface exploration. Only two years after the first manned landing, which at the time had seemed like the ultimate achievement, we engineers had produced a design that opened new vistas of scientific discovery. Three days on the Moon allowed at least three moonwalks, and the rover loosened the bonds of physical exhaustion, enabling the explorers to be out on the surface for up to seven hours at a time, tackling distances and slopes that walking astronauts could not. The rover also saved the crew’s strength by carrying their tools and samples and provided precision surface navigation that minimized wasted time seeking landmarks. An advanced TV camera on rover let the whole world share in the thrill of the moonwalks and allowed the lunar geologists in the back room at Houston to take part in their students’ field trip and assist with suggestions and evaluations. Lee Silver and the other senior geologists who had tutored the astronauts not only watched them perform but actively participated in the expedition, looking over the explorers’ shoulders though a quarter million miles away. The world had never seen anything like it.

Apollo 15’s landing site was the most challenging yet attempted by the program, and a very beautiful and dramatic area. It was situated on a level plain bordering Hadley Ridge of the lunar Apennine Mountains, between towering eleven-thousand-foot Mount Hadley Delta and Hadley Rille, a sinuous three-thousand-foot canyon. Scott and Irwin were startled when the LM Falcon pitched over at nine thousand feet to see the brilliant sunlit flank of Mount Hadley Delta above them to the left. The scene ahead was unfamiliar, and Mission Control informed them that the guidance system had put Falcon three thousand feet south of where it should be. Thanks to the prominence of Hadley Rille and Mount Hadley Delta, Scott was able to correct their flight path manually and land very close to the target point. Dust obscured his vision for the final sixty feet, making this the second LM to touch down on instruments. In view of their intended three-day stay on the Moon and the long
duration of their planned moonwalks, Scott and Irwin planned to sleep before setting foot on the Moon. But first Scott conducted a visual reconnaissance of the area, as Lee Silver had taught him to do at any new field site. Depressurizing Falcon’s cabin, he raised himself halfway out of the upper hatch, and for half an hour he gazed at and photographed scenes of unsurpassed beauty and grandeur: the rounded gray flanks of Mount Hadley, covered like a ski slope with the untouched snows of eons of cosmic dust, and the winding, mysterious depths of Hadley Rille, perhaps holding a key to the Moon’s history written on its walls. He was thrilled at the prospect of exploring such a vista.
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