Moon Lander: How We Developed the Apollo Lunar Module (Smithsonian History of Aviation and Spaceflight)

by Kelly, Thomas J.

  I followed Munier into Sanial’s small cubicle deep inside the Preliminary Design mezzanine. We were greeted by a tall, trim fellow with a long, freckled face. His hair was more gray than black, a contrast to his boyish, youthful face. He was neatly dressed in a blue blazer jacket and tie, even hidden away in this obscure den.

  “Tom Sanial, meet Tom Kelly,” Munier said breezily. “He’s here to work with you on Apollo.”

  Munier left us alone together in awkward silence as we sized each other up. Were we to be partners or rivals? Sanial’s innately generous nature took over. Soon he was showing me his files and describing what he had learned of the Apollo Project. He was persuasive and persistent as he related the steady growth of the program shown by NASA’s statements, budgets, and planning documents. He had become convinced that NASA was seriously planning a manned exploration of the Moon.

  I moved into the desk next to his in the cinder-block cubicle, which had six desks in all, and pored over the documents he had collected, along with his technical notes and trip reports. In the spring of 1960 we visited NASA Headquarters and the Langley and Lewis Research Centers, where I met DeMarquis “Dee” Wyatt at Headquarters and George Low at Lewis. They spoke in guarded terms, making clear that the manned lunar mission was in an early phase of internal review and was not part of NASA’s firm plans. Their intense interest, however, indicated that the program was a serious possibility. I concluded there was at least an even chance that Apollo might happen, and that Grumman had better get prepared.

  Suddenly our company was a full-fledged player in space: Grumman won the OAO competition. Eight aerospace companies had fought for this major NASA program, with its possibility of discovering new worlds in astronomy, and Grumman, known mainly for its World War II Wildcats and Avengers, had been a long shot. At the OAO victory party, some of my colleagues asked if I would be joining them on the project.

  “I don’t think so,” I replied. “Gavin and Murder want me to work on Apollo.”

  “What’s that?” they chorused.

  “It’s a program of manned exploration of the Moon.”

  “Send men to the Moon? Are you crazy?” one engineer scoffed.

  “NASA seems serious about it. They’re planning to spend billions of dollars to make it happen.”

  “Come on, Tom, that’s Buck Rogers stuff. Towl and Titterton aren’t going to stick Grumman’s neck out for something like that. Face it—it’s amazing that we were even allowed to bid on OAO. We wouldn’t know where to begin a trip to the Moon.” When he walked away shaking his head and laughing, I wondered if my career was headed for oblivion.

  Now that Grumman was a serious space contender, Apollo became a more urgent business objective. NASA convened an Apollo industry planning session in late July 1960 that was attended by more than thirteen hundred people. At this conference they announced their interest in a manned lunar landing and showed the results of their engineering studies. Although not yet an official program, NASA interest in Apollo was very serious.

  Sanial and I convinced Murder that we should form a small study group to educate ourselves about manned lunar missions. Munier spoke to Walter Scott, chief of Preliminary Design, who approved budget for ten people. We recruited the specialists we needed in aerodynamics, orbital mechanics, flight dynamics, and control and weights. Sanial and I were co-leaders of the study. He would also handle structural design while I covered propulsion.

  We read everything published about Apollo and lunar missions in general and formulated a plan for a manned lunar mission feasibility study. In October 1960 we submitted this study plan as a proposal to NASA in an industry competition for the launch and lunar trajectory phases of the mission. (The overall plan for accomplishing the mission was not yet addressed.) We lost to Gonvair, General Electric, and Martin, but Grumman management (Walter Scott and Joe Gavin) decided to conduct our study anyway, using company money.

  Two pressing issues for the study were the shape and aerodynamic characteristics of the manned reentry vehicle. Reentry through Earth’s atmosphere from escape velocity (twenty-six thousand miles an hour) was much more difficult than from Earth orbital velocity, in terms of both the heat the vehicle must withstand and the guidance, navigation, and control (GNC) accuracy needed. The returning spacecraft had to enter a narrow window of allowable reentry angles, between 5.5 and 7 degrees, when it encountered the upper edge of Earth’s atmosphere. Too steep an angle would cause the spacecraft to burn up; too shallow an angle would skip the craft off the top of the atmosphere to wander aimlessly through the solar system for eternity.

  Even after reentry, when the spacecraft had decelerated to high supersonic speed in the lower reaches of the atmosphere, it must still maneuver to reach the landing area. A blunt body, like the Project Mercury capsule designed by Max Faget, a highly creative aeronautical engineer working for Bob Gilruth in the Space Task Group (STG) of NASA’s Langley Research Center, had no aerodynamic maneuvering capability (lift-to-drag ratio [L/D] = 0). However, such a body spread the atmospheric frictional heating over the large area of the blunt end, making insulation and heat absorption easier. Lifting bodies, like the series of aerodynamic shapes developed by Alfred Eggers at NASA’s Ames Research Center, had significant aerodynamic maneuvering capability (L/D = 0.5 to 3 or 4), which allowed them to glide several hundred miles to reach a specified landing area. But these shapes concentrated the aerodynamic heating on the vehicle’s nose and the leading edges of its stub wings and tail, creating temperatures of several thousand degrees. Still, the lifting body made the job of the GNC system somewhat easier, because it could maneuver to compensate for errors in targeting the landing area from space. There were many interesting engineering tradeoffs and design compromises to be considered.

  Our lifting body expert was Bob Lecat, an irascible and volatile pipe-smoking man of French heritage. A brilliant aerodynamicist, Lecat was devoted to his work, but at times that devotion caused him to appear unconcerned with the feelings of others. His gruff voice could often be heard lamenting the stupidity of Grumman management and of most of his engineering colleagues. With me he adopted an air of patient condescension, as though explaining Aerodynamics 101 to the village idiot.

  Lecat designed a family of lifting-body shapes for analysis and comparison with the Mercury blunt body. His results were a principal element of our study report. In addition to analyses and wind-tunnel tests, Lecat built a model from balsa wood and tissue paper of his favorite design and flew it around the parking lot, getting derisive comments from aircraft engineers about its bloated appearance.

  On 15 May 1961 we submitted our summary report to NASA, maintaining that a manned lunar mission was feasible. We presented the results of our reentry vehicle studies but left the choice of body shape open. Blunt bodies, lifting bodies, and winged vehicles all looked workable from a GNC error tolerance viewpoint, but the tolerances opened up with increasing L/D. Material and design difficulties increased with L/D, but the lifting bodies appeared feasible with advanced materials and manufacturing techniques.

  The NASA-funded studies were much more thorough and elaborate than ours. Each of the three contractors spent more than a million dollars, although NASA had paid each only $250,000. At their midstudy reviews, each contractor chose a specific lifting body reentry vehicle. None recommended a blunt body, which annoyed Faget, who said in his Louisiana drawl that they just did not understand the problem. In their final reports, however, the contractors had gotten Faget’s message: GE and Martin recommended blunt-body command modules, although Martin added flaps to give it some maneuverability. Martin’s nine thousand-page report was the largest, the result of three hundred people working for six months and spending $3 million.2

  We presented our results to NASA’s Space Task Group a few days after the funded contractors’ briefings. Considering the size of our investment—we averaged fifteen to twenty people on the study and probably spent less than $250,000—NASA gave us an attentive hearing and seemed in
terested in our results. Faget lectured us briefly on the advantages of blunt-body reentry vehicles, contending that they made reentry heating tolerable by known, practical materials. He thought we should drop lifting bodies from further consideration because they required state-of-the-art advances in high-temperature materials. But Faget also said that our study results were in line with NASA’s own work. I felt that our effort on the study had been a good investment.

  Throughout the LM studies and proposal I relied heavily on my deputy, Erick Stern, a brilliant analyst with a flair for debating and selling his ideas. Stern’s work on the inertial guidance system for the Atlas ballistic missile at American Bosch Arma Corporation gave him practical experience with a critical system for spaceflight: guidance, navigation, and control. He broadened this to embrace the rapidly developing field of systems engineering pioneered by the air force and navy ballistic missile programs. I used him as a sounding board for all technical problems, whether or not they fit his background, and always received carefully reasoned answers.

  Stern was tall and heavy-set, with a high forehead, thinning blondish brown hair, a pale face, and blue eyes behind a pair of thick glasses. He looked every inch an intellectual. He had grown up in Vienna and been brought to America by his parents before the war, and his trace of Viennese accent enhanced his professorial image. He worked his way through City College, where he earned a bachelor’s degree in electrical engineering, and then, while working at Arma, attended New York University at night and obtained a master’s degree.

  Stern and I worked well together; we respected each other and both enjoyed serious technical discussions. Not everyone could keep up with Stern’s racing mind, though, and he could lose patience with those who did not follow his arguments, no matter how high their rank. Some people took offense at Erick’s frank manner, but it never bothered me, and only later did I realize that influential NASA people resented him. I felt that he was always trying to instruct and persuade, not put down others. His arguments had none of the dismissiveness I often sensed from Lecat. Not that Stern ever hesitated to point out where he thought I was wrong, even in the presence of others, but he was loyal to me, and he was skillful and dedicated to his work on the program, which overshadowed any minor carping about other facets of his personality.

  In the meantime, a major debate was raging within the Kennedy administration to identify a space mission that would allow the United States to recapture the lead in space technology from the Soviet Union. The cold war had flared up, and the global competition between two diametrically opposed social systems broadened into the arena of outer space.

  On 12 April 1961 the Soviets launched Yuri Gagarin, the first human to orbit Earth. A few days later the U.S.-sponsored Bay of Pigs invasion of Cuba failed ignominiously. President Kennedy was looking for a way to regain the initiative from the Soviets. He turned to his vice president, Lyndon B. Johnson, and the newly appointed NASA administrator, James E. Webb, for recommendations for a “space spectacular” that would clearly establish American preeminence.3 The feasibility studies that we and the other contractors submitted fell on fertile ground.

  Ten days after our report went into NASA, Kennedy declared before a joint session of Congress, “I believe that this nation should commit itself to achieving the goal, before this decade is out, of landing a man on the Moon and returning him safely to Earth. No single space project in this period will be more impressive to mankind, or more important for the long range exploration of space, and none will be so difficult or expensive to accomplish.”

  The dreaming and studying were over. America was going to the Moon! In our dreary Preliminary Design cubicle, Sanial and I could scarcely believe our good fortune. We grinned foolishly at each other: the roulette wheel had stopped on our number. What would it be like to build spaceships to fly to the Moon?

  “I’ll bet the real Apollo won’t look like any of the vehicles we’ve studied,” ventured Sanial.

  “Why do you say that? Don’t you think we’ve done a good job?” I challenged.

  “Our study was okay as far as it went, but I’m sure we’ve just probed the obvious. There’s still so much we don’t know about how to fly to the Moon.”

  I had to agree with that. “You’re right. We don’t even know yet what we don’t know.”

  The opportunity was there, now we just had to find a way to get a piece of it for Grumman and ourselves. If we succeeded, we would be part of history.

  Losing Our Nerve

  After President Kennedy’s announcement, the scale and pace of Grumman’s Apollo activities surged. Joe Gavin was put in charge of the Apollo studies as chief missile and space engineer. Sanial and I led the technical effort for the studies, reporting to Gavin and Munier. Our study group expanded from thirty to sixty people, including senior engineers such as Erick Stern and Bob Watson, a highly regarded GNC designer from the Dynamic Analysis Section in Engineering.

  Gavin and Munier explored alliances with other companies to strengthen our lunar mission study effort. We were interested in both the technical expertise that specialists in technical systems could add to our studies and the contribution of skilled people and technology that other companies could make. Honeywell joined us first, in GNC, and Space Technology Laboratories (STL) joined next, in electronic systems and program management. Each brought new ideas and talent. We housed them, together with the added Grumman members of our expanded study group, in a large open area in the center of the PD mezzanine that had previously been reserved for major aircraft proposals. Munier, Sanial, and I and some of the other Grummanites stayed in the secluded Space Sciences corner adjacent to the main mezzanine floor.

  The Apollo spacecraft request for proposals (RFP) was released to industry in July 1961, and in August NASA hosted an Apollo bidders’ conference in Washington, D.C. In between the formal sessions, and at breakfast, lunch, and in the evening, contractors engaged in frantic mating rituals: exploring potential alliances for bidding on the Apollo program. Hasty assignations between contractor representatives took on a comic-opera air, with intense whispering behind the potted palms.

  Joe Gavin, Saul Ferdman from Space Marketing, Bob Watson, and I all performed mating dances with potential teammates, either together or separately. When we compared notes at the end of the day, we sometimes found that a suitor was in bed with more than one company. We learned that there were at least as many companies who wanted Grumman to be a subcontractor as were willing to consider joining a Grumman-led team. Nobody got married, but there was a lot of heavy dating.

  At the formal sessions, NASA described the scope of the Apollo Project and summarized the primary requirements that would be in the RFP. They planned to release the RFP within two or three weeks, allowing sixty days for response. The program was even bigger than we had envisioned. It included a three-man command module blunt-body reentry vehicle, a supporting unmanned service module containing consumables (such as propellants, helium, water, and oxygen), electric power, electronics and antennas, and a large restartable liquid-propellant rocket system. A launch escape rocket for the command module and a large cylindrical structural shell to support the service module atop the upper third stage of the Saturn booster rocket would also be supplied by the Apollo spacecraft prime contractor. Also required were the ground-support equipment (GSE) necessary to test and service the spacecraft and the integration of all the space and ground components into a functional system that could send men to the Moon and return them safely.

  Apollo would be the biggest engineering job in history. Joe Gavin thought it was bigger than building the pyramids or inventing the airplane and would take every ounce of ingenuity for us to pull it off.

  When Gavin reported to Grumman’s top management that the Apollo RFP was imminent, he was asked to recommend what the company should do. Sanial and I prepared the technical briefing based upon our study results. We argued that Apollo was feasible and that we knew how to do it. We rehearsed our briefing several times before
Gavin and Murder. Gavin and Ferdman gave the management briefing and budget request. They strongly recommended that Grumman bid as prime contractor. They estimated the budget necessary to prepare a winning proposal along with the facility and capital equipment investment required to perform the job: all huge numbers by Grumman standards.

  The briefing was held in Grumman’s mahogany-paneled board room to an audience seated around a large boat-shaped table. Grumman’s president, E. Clinton “Clint” Towl (pronounced “Toll”), and executive vice president, William T. “Bill” Schwendler, were there. Both were founders, in December 1929, of Grumman Aircraft Engineering Corporation in Baldwin, Long Island. Clint Towl led the fledgling company in business management and administration. A reserved man of carefully chosen words and dry wit, he had curly brown hair and an intense stare behind small, gold-rimmed eyeglasses.

  Bill Schwendler had been hand-picked by Leroy “Roy” Grumman at the predecessor Loening Corporation to be his engineering protégé and problem solver. Schwendler absorbed everything then known about aircraft design from his talented pilot-engineer-inventor mentor and became the company’s chief engineer as Roy Grumman inevitably became more enmeshed in sales, customer relations, and general management. Bill recruited Vice President of Engineering Dick Hutton and other Grumman engineering leaders and guided the rapid growth of the Engineering Department. He had a ruddy, angular face, blond hair so thin and fine that he appeared almost bald, and vivid blue eyes, which he fixed unblinkingly upon his subject.

  Two of Grumman’s earliest employees were also there: Vice President of Engineering Richard “Dick” Hutton, who was chosen by Schwendler to succeed him as chief engineer, and Senior Vice President George Titterton, who directed Contracts, Business Administration, and Marketing. Chief Technical Engineer Ira Grant Hedrick, Grumman’s most respected analytical engineer, rounded out the decision-making group.