SP-480 Far Travelers: The Exploring Machines

 

Ranger: Murphy's Law Spacecraft

 

[96] If it is proper to feel sorry for spacecraft, Rangers deserved sympathy. Like the firstborn of pioneers, they had inexperienced and distracted parents with great expectations, and a wholly unknown environment to cope with. Worst of all, they had a perverse affinity for that malicious principle credited to Murphy: if anything can possibly go wrong, it will.

When the first definition of a lunar program came about, the United States was just beginning to organize the National Aeronautics and Space Administration into the singularly competent organization it would become. New people were being hired and sorted into teams, new managerial structures were being invented, and new standards of planning, quality control, and operations were being developed. At the nucleus of the new agency were groups of able engineers from three or four predecessor organizations who could draw on prior experiences of a somewhat related nature, but no one had ever done what NASA set out to accomplish. This time of ferment was not limited to the new agency. Widely spread in both industry and in academic communities were pockets of able, hard-driving people eager to find reputation and reward in the newly accessible territory of space. The military services were much a part of the scene, drawing activities from ballistic missile programs. Born in this turbulent period in 1958 and 1959 Ranger was still struggling for success 3 years later when its Mariner derivative succeeded in visiting the planet Venus.

The Ranger program was particularly bedeviled by the fact that its launch vehicles were being developed and perfected concurrently. Earlier Pioneers 1 to 4 (all lunar spacecraft that were launched into space but did not reach the Moon) had flown on Thor/Able and Juno intermediate-range ballistic missiles of very limited payload. Mission and payload design studies conducted by JPL in 1958 influenced NASA's decision to use an Atlas ICBM (rather than a Titan), since the Atlas flight test phase had already started and was well along. Unfortunately, an upper stage suitably matched to the Atlas [97] for missions to the Moon and the planets did not exist. The initial plan called for JPL to develop a new upper stage to be called Vega; combined with Atlas it would be capable of launching Earth satellites and deep space payloads of 500 to 1000 pounds. Then, on December 11, 1959, NASA canceled Vega and directed JPL to relegate to research status its work on a 6000-pound-thrust Vega engine. A study group that included members from JPL led to the establishment of the Atlas/Agena B vehicle program as a replacement; the integration of this new vehicle combination was placed under the direction of the Marshall Space Flight Center.

The initial plan to use Vega had an impact on Ranger design, not simply because of the change from one vehicle to another but also because Vega and Ranger had been conceived as an integrated set. The Vega was to have had six longerons-the fore and aft framing members-and the Ranger spacecraft was designed with a matching hexagonal symmetry to ensure the lightest carry-through structure from the launch vehicle to the spacecraft.

When the Agena B replaced Vega as the upper stage of the launch vehicle, a considerable amount of work had already been performed to maximize payload weight and to relieve liftoff time constraints. To effectively launch a spacecraft to the Moon it was necessary to include a variable coast phase-sometimes called a "parking orbit"-and the Agena B's existing restart ability made this possible without additional staging. The existing guidance systems had sufficient precision, provided the spacecraft could make a midcourse maneuver for trajectory correction.

As specifications were finally established, a standard USAF Atlas/Agena B could, with minor modifications, carry a lunar spacecraft weighing 700 to 800 pounds. This vehicle was the only promising and, we thought, reasonably developed capability at hand. It was not ideal for interplanetary missions; the staging arrangement was unconventional, joining a 1 1/2-stage vehicle with a restartable second stage. A three-stage launch vehicle would have been more suitable, but the time and costs that would have been required for development were prohibitive. Despite being a combination of an ICBM designed to deliver a 1500-pound warhead on a 5500-nautical-mile trajectory and an upper stage intended to supply orbital velocities after launch atop an intermediate-range Thor missile, the Atlas/Agena was, by the standards of the time, a formidable booster.

The Atlas, developed in the mid-1950s by General Dynamics, stood some 66 feet high, weighed 130 tons fueled, and had a sea level thrust of 370 000 pounds. The half stage consisted of two big Rocketdyne engines to be [98] jettisoned 2 minutes after liftoff; the remaining first stage was a single large Rocketdyne sustainer engine, supplemented with vernier engines to fine tune the velocity. The bulk of the vehicle was taken up by giant propellant tanks containing liquid oxygen and RP-1, a kerosene-like fuel. So thin were the tank walls that the erected Atlas would crumple from its own weight if the tanks were not filled or pressurized. The Agena, developed in the late 1950s as part of an Air Force satellite project and modified for NASA space mission use, was powered by a Bell rocket engine of 16 000 pounds thrust. Its propellants were two unsavory chemicals known as unsymmetrical dimethyl hydrazine and inhibited red fuming nitric acid.

The transition of responsibilities for launch vehicles from military to space users began in the early days of NASA. High-level negotiations between NASA and Air Force officials initially focused on launch vehicle procurement and launch responsibilities. The fact that all potential space vehicles at the time were outgrowths of missiles meant that the military had been in control of these developments. The formation of NASA as a civilian agency gave it authority to develop vehicles, but there was no prudent way to begin without working out arrangements with the military for an orderly integration of requirements and procurements. The Air Force initially said regarding the Atlas/Agena, "Don't worry about a thing, NASA, we'll put you FOB on orbit," meaning that they would accept total responsibility for launch vehicle procurement, launch, and operation. This proposal was not accepted, and meetings continued at all levels until agreements were signed allowing NASA to have its own contracts for vehicle modifications and establishing NASA-controlled launch operations with military support. There was, however, a truly difficult transition period that lasted well into the mid-1960s.

The Atlas/Agena B launch vehicle and associated facilities, including launch-to-injection range support, were originally under the cognizance of the NASA Marshall Space Flight Center. This was an inherited responsibility, however, and Marshall procured the vehicles through the Air Force Space Systems Division (AFSSD). AFSSD administered the contracts and directed the contractors so that Marshall "could obtain maximum benefit from established Air Force procedures" and so that interference between the NASA programs and high-priority military programs was minimized. Lockheed Missiles and Space Company supplied the Agena stage and was the vehicle system contractor responsible for such areas as structural integration, trajectory and performance analysis, testing, operations planning, and....

 


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Ranger 3 mission payloads.

Ranger 3 mission payloads.

 

[100] ....documentation. General Dynamics/Astronautics was the contractor for the Atlas; both contractors had complete responsibility for their stages, with some uncertain assignments of responsibility for their integration. Marshall was supposed to integrate the two stages built by contractors, and JPL was to be responsible for overall integration of the vehicle with the spacecraft.

The Marshall assignment was a tough one; there were coordination problems and problems related to the inherited contractor arrangements, and the tasks were interwoven with Air Force activities. The Air Force actually had a more complex organization than NASA, with interfaces between its Space Systems Division and its contractors, and the Launch Operations Division and its contractors at Cape Canaveral. In addition, as already mentioned, within Marshall, the Atlas-based vehicles competed with the new Saturn program for personnel resources.

In August 1963, after work on the Centaur bogged down, responsibility for the Atlas-based vehicles, both Agena and Centaur, was transferred to the Lewis Research Center. Launch operations at the Atlantic Missile Range, previously under the direction of the launch operations directorate of Marshall, were reassigned to the Goddard Space Flight Center launch operations branch

On December 21, 1959, NASA Headquarters sent JPL a detailed guideline letter outlining five lunar flights that emphasized obtaining information about the Moon's surface. The letter also requested that JPL "evaluate the possibility of useful data return from a survivable package incorporating . . . a lunar seismometer." This letter was the formal basis for what became the Ranger Program. Aside from the faint, ghostly Vega influences mentioned earlier, other influences shaped Ranger, some of them more useful to later interplanetary flights than to the immediate lunar mission. The Ranger concept called for a basic spacecraft to carry a variety of payloads, allowing development experience and costs to be amortized over several missions. Three different types of Rangers were developed. Although all were planned for launch on lunar trajectories, the first two were actually interplanetary spacecraft intended to obtain scientific information at great distances from Earth, with goals of developing the basic spacecraft technologies and adapting to the new Atlas/Agena launch vehicle.

The second block of three Rangers, more sophisticated in concept, were intended to make scientific measurements, including gamma-ray spectrometry, on the way to their destination, to take TV pictures on approach, and to land survivable capsules containing seismometer payloads on the [101] Moon. Though none succeeded, the attempt was brave and technically interesting, paving the way for future successes.

The last four Rangers had the specific goal of returning close-up pictures of the Moon's surface, using six television cameras capable of returning thousands of frames during the last 2 minutes before crashing on the Moon. While somewhat less ambitious technologically than landing survivable payloads, this block of Rangers produced three brilliant successes and represented a maturity in planning that comes with experience.

It should be noted that the block concept used with Ranger was derived from proven practices in the aircraft industry. Efficiency and reliability were believed to be best served by maintaining a constant configuration for a series or block of articles, only allowing new developments or modifications into grouped changes to the "production line." Although it was hard to see the merits of this concept from the early Ranger results, I still believe that it paid off, considering the total lineage of Ranger and Mariner hardware. In spite of this production-based philosophy for manufacture, I always tried to get the project team at JPL to regard each spacecraft as if it were the only one we had, vainly trying to achieve 100-percent success from the outset. After several failures, that management position was questioned by our critics, some sarcastically labeling Ranger a "shoot and hope" project. But as far as I am concerned, 100 percent success was a basic aspect of NASA philosophy from the outset.

While not all the concepts factored into Ranger design were essential for a trip to the Moon, they made it a kind of forerunner of interplanetary craft. It had become evident that opportunities for engineering development flight tests would be very limited for this class of spacecraft because the costs would be so high, yet mission criteria demanded sophisticated spacecraft designs. Thus, there was little hope of reaching a high probability of success for a single launch unless major parts of the spacecraft design remained the same from flight to flight to permit development experience. All hardware could not be new at every launch, in other words, and still provide a high probability of success. This view, together with recognition that only a fraction of total spacecraft weight could be decelerated by a retro rocket for a landing on the Moon, led to the bus-and-passenger concept for the Ranger/Mariner spacecraft that has been a hallmark of lunar and planetary missions.

A Ranger approaching the Moon from the distance of Earth on a minimum energy trajectory would normally impact at more than 4500 miles [102] per hour. After arriving within a predetermined distance of the surface, a capsule-equipped Ranger was to be oriented to align its capsule rocket axis with the vertical descent velocity vector, and a marking radar was to call for spinup, separation from the bus, and firing of the rocket. After rocket burning to completion, the reduced approach velocity would allow a capsule to fall to the surface of the Moon at a survivable impact velocity. It was a novel capsule system, weighing a total of 300 pounds, made up of a small solid rocket and a mini-spacecraft enshrouded in balsa wood.

After studies by three contractors, Aeronutronics, a division of Ford Motor Company, had been chosen to design, build, test, and deliver three flight articles for a total of $3.6 million. Included were a special solid propellant retro motor, a radar altimeter to bounce signals from the lunar surface and trigger the retro at the proper instant, a crushable outer shell capable of withstanding impact on hard rock at up to 250 feet per second, and a spherical metal instrument package floated inside in a fluid to distribute and dampen impact loads. The flotation feature in some ways resembled the design of an egg, known to offer impact protection by reason of the fluid inside; it also provided for automatic erection and orientation of the package after landing. The instrument carried was a single-axis seismometer; also included were signal-conditioning electronics, a transmitter to report to Earth, and batteries to provide power for a 30-day lifetime on the Moon. The crushable outside structure was developed after an extended series of engineering tests of a variety of materials. As it turned out, the best impact absorbers were made of balsa wood, assembled around the capsule with the end-grain about 4 inches thick oriented in a radial direction.

This sophisticated little spacecraft-within-a-spacecraft system was carried toward the Moon on three occasions. On the first try a launch vehicle failure spoiled its chances; on the second and third trials troubles aboard the Ranger bus brought it to naught.

For a time we had hopes of follow-up missions using the capsule concept for landing other kinds of payloads on the Moon. One was a facsimile camera that, after landing, would poke its head through the balsa shell for a look around; it was a simple device with a nodding mirror that would do a line scan of the lunar landscape. The camera system and its capsule were developed satisfactorily and tested on Earth, but the program was canceled before this system got a chance to prove its worth.

Ranger bore the brunt of the difficult constraint imposed by sterilization. Any spacecraft likely to land on the surface of the Moon or a planet, by accident [103] or by intent, had to be free of Earth's pervasive microbial population. This scientifically imposed international requirement placed a tremendous burden on Ranger engineering and development, and greatly multiplied costs. Of course, it also took its toll on the useful life and reliability of sterilized components and is believed to have had a seriously degrading effect on early spacecraft performance.

As an aside, the stringent requirements for heat sterilization may have, in the long run, resulted in the development of more reliable hardware, in much the same way that insecticides cause insects to develop an evolutionary resistance. But early Ranger spacecraft had to pay the price of meeting these stringent requirements. While there never was any positive proof that sterilization caused difficulties with electronic gear in space, there were many reasons to believe this was a factor in the high initial failure rates.

One incident from my earliest association with the Ranger project comes to mind as an illustration of project "growing pains." On first viewing the prototype spacecraft, I noted that the superstructure supports for the omni antenna were just four tubes attached to the bus and sloping upward to the smaller diameter base of the cylindrically shaped omni. Having been trained as an aeronautical engineer with heavy emphasis on light-weight structural design, I was immediately conscious of a difference between this structure and trusses common in aircraft structures.

"Where are the diagonal members to react against torsion," I asked. "Oh, there won't be any torsion loads," was the reply given. I knew well that almost any combination of compressive and lateral loads would result in torsion on a tapered structure, but being new and very conscious of the delicate relationship that had been created by the NASA "takeover" of JPL, I merely registered concern and went on to other matters.

In just a few weeks the vibration tests of the structure showed the need for diagonal bracing, as the torsional deflections were very severe. Diagonal members were quickly added, and I learned of a situation I was to encounter again many times. My assessment of the problem was that there were two contributing factors: (1) There was so much high technology associated with the conduct of a space mission that JPL project officials didn't spend time worrying about freshman-level design problems, (most young JPL engineers were trained in electronics and may have had little regard for civil engineering courses like Statics), and (2) the academic management style then operating at JPL gave independent responsibilities to many inexperienced people who were expected to function without supervision.

[104] This was vastly different from the aircraft industry style of management I was used to, where a Chief Engineer and a highly structured organization made all key design decisions from the top down. Of course, after twelve years in the industry environment I thought JPL would benefit greatly from more discipline, and spent much effort during the years that followed trying to make this happen. But, as already stated, evolutionary changes in the JPL management style came slowly, and largely as a result of failures in early projects.

During the prelaunch phase for Ranger 1, meetings at the Cape were extremely confusing, as AFSSD representatives, launch operations representatives, Marshall and JPL personnel joined on their first mission of this series In addition to the two principal launch vehicle contractors, General Dynamics and Lockheed, there were several other contractors responsible for guidance, tracking, and other services. Those early Ranger meetings were difficult scrimmages, part of the process of assembling, sorting out, and breaking in a new team. By the time Mariner 2 was launched, many of the pitfalls had been discovered, and the Mariner team had some insight into what was necessary; however, four Ranger launches had borne the brunt of the transitional jumble.

One of the key people involved in early operations at the Cape was Harris M. "Bud" Schurmeier. Bud was chief of the Systems Division at JPL, which had three major project functions: (1) systems analysis, including flight trajectory design, orbit determination, and the overall analyses required to establish midcourse and terminal maneuvers, (2) systems design and integration for the basic layout of the spacecraft and the entire supporting elements, and (3) spacecraft assembly, systems test, prelaunch checkout launch, and flight operations. This single division contributed the "core group" of engineers who were involved directly in all missions, and it was therefore part of Schurmeier's responsibility to oversee a host of activities at the Cape that were essential to both Ranger and Mariner missions during the early days.

Bud and I recall early prelaunch readiness meetings at Cape Canaveral when a room full of people, including the various contractors, Air Force NASA, and JPL personnel, convened for status reports. These early meetings were initiated without a disciplined agenda and with some uncertainty about who was in charge; they were presumably to allow each group to report to the others where they stood in their preparations for launch. Many of the people did not know each other, and at first there was no clear understanding [105] of the role each group was playing. The spokesmen around the room would gleefully report progress until someone announced that his group was having a small problem. Upon digging into details, interactions with others would usually surface, and the meeting would end with some people not having to tell of problems, pending resolution of those that had come to light.

The hope that someone else would become the "fall guy" and allow more time to fix things would sometimes encourage bluffing, which only succeeded in hiding a difficulty if no one else knew of the problem. However, since many interface situations existed, there were lots of ways to be found out. Alert project managers got people "calibrated" and were better able to "sniff out" the true situations. A few of the participants were forced to disclose their problems after all the initial reports around the room-including theirs-had been favorable; it soon became obvious that it was much less embarrassing to be completely forthright from the beginning.

In reviewing some of his early impressions of activities, Schurmeier described his first project meeting at the Cape in this manner: "That was a real eye opener in a sense. The thing that depressed me was that so many different groups and organizations were all involved in various ways. It reminded me of a bunch of ants on a log floating downstream, each ant thinking he was steering. With the bewildering array of people involved and incomplete knowledge of all the facets of the operation there was a tendency on the part of the project manager to say, 'If everything is getting done and going the right way, leave well enough alone, and I don't care who thinks he's in charge.' " If things had really been getting done, this view would have been acceptable, but results soon proved the hoped-for success to be a fantasy. Bud's successful involvement in so many of the key project activities eventually led to his selection as Ranger Project Manager, when, after five failures, it was decided that a strengthening of the project team and a change of principal leadership was required.

In May 1961 I signed the review of qualification tests and approved shipment of the first Ranger to the Cape. A multitude of things had to be done to check out the spacecraft, the launch vehicle, and the launch facilities after the spacecraft arrived. The first Ranger launch window was from July 26 to August 2, with about a 45-minute window each day. In addition to scheduling launches to match the lunar cycle, there was a frenzied environment of launches about the time that required schedule coordination with range services and other project offices. We thought everything was ready on July 26, [106] only to find to our dismay that the Range Safety Officer, the "bad guy" who was charged with blowing things up if the boosters went astray, did not have the trajectory information he needed. This caused a 1-day delay, to be followed by another delay the day after because an Atlas guidance system malfunction came to light. A third day was lost when a guidance program error was found in the input to the Cape computer.

These delays before the first countdown got underway were just the beginning. When the first count was within about 28 minutes of T-zero the entire blockhouse was plunged into darkness. The time was about 5:00 A.M, and it turned out that a short in primary power had been caused by the contraction of new power cables that had made contact with old conductors not yet removed. Those lines could be clearly seen, perhaps only a few hundred yards away from the blockhouse, when daylight came. Talk about frustrations!

Countdowns 2, 3, and 4 were scrubbed because of Ranger spacecraft checkout problems and another Atlas problem that surfaced. The final spacecraft failure-an electrical malfunction that triggered multiple commands from the CC&S-caused the spacecraft to be removed from the vehicle for repairs and the launch to be rescheduled for the next monthly opportunity in August. The only good thing about the frustrating experience was that we still had our hardware; at least it was not in the ocean. This "happy thought" was only slightly reassuring at the time.

Ranger 1 was finally launched in August 1961, a test flight not aimed at the Moon but intended to go to lunar distance and beyond. The Atlas/Agena was for the first time trying an Earth-escape type of mission, but failed to put the spacecraft on the highly elliptical trajectory being sought. Instead, Ranger was injected into a low Earth orbit and reentered the atmosphere after 7 days. Postflight analysis suggested that the problem was a switch circuit controlling propellant valves. Ranger seemed to have performed right, though short viewing times and movements into and out of Earth's shadow did not provide a meaningful test.

The next flight 3 months later had similar objectives and was a disgustingly comparable failure, with orbit at an even lower altitude and reentry after a few hours. This time the problem was overheating of some critical wiring in the Agena during the parking orbit period. After corrective action had convinced engineers that neither of these failures would recur, Ranger 3 was launched with considerable confidence, targeted to hard-land a capsule on the surface of the Moon. This time some booster circuitry that had behaved [107] satisfactorily on the two previous flights failed, and the spacecraft was accelerated to a much higher velocity than desired, causing it to reach the Moon's orbit ahead of schedule and to miss the Moon by more than 22 000 miles. This prevented a true test of the hard-landing system, but when an attempt was made to exercise the landing system through commands, wiring problems were revealed that would have compromised the results even if the launch had been successful.

Finally, the launch vehicle for Ranger 4 performed beautifully, and launch computations revealed that the spacecraft would arrive at the Moon with no further course correction. Elation at this news was short-lived; engineering telemetry soon revealed that the spacecraft's central computer and sequencer, the heart of its control system, had lost its clock and could not perform the timing functions necessary for midcourse correction and approach maneuvers.

After all the earlier troubles, this mission looked somewhat better because of predictions that the spacecraft would impact the Moon. The Russians had sent a pennant to the Moon 2 years earlier, and Nikita Khrushchev had chided us publicly by quipping that their pennant had gotten lonesome waiting for an American companion. Administrator James Webb, who was in Los Angeles for a speaking engagement, was escorted to the Goldstone tracking station by Bill Pickering and me to witness the tracking to impact. This was a dubious honor; I would have enjoyed the trip more if we were to see a successful landing, but Mr. Webb was very gracious about supporting the team publicly in a press conference that followed.

We never will know the cause of the malfunction, but extensive engineering redesigns were made to the CC&S that prevented such a problem from recurring. Ranger 5, the last of the block of spacecraft intended to provide a survivable landing on the Moon, was launched in October 1962, shortly after Mariner 2 had begun its long trip to Venus. Ranger's launch vehicle performed well within the desired accuracy, placing the spacecraft on a flight path that would come within 450 miles of the Moon, easily within the capability of the course-correcting rocket onboard. But soon after the spacecraft was oriented so that the Sun would illuminate the solar panels, engineering telemetry reported a malfunction, probably in the switching circuitry for use of solar power.

After a few hours the batteries were depleted, and the spacecraft could not respond to commands to fire the rocket that would have placed it on a collision course with the Moon. By the time it reached the vicinity of the [108] Moon, all systems aboard were dead except for a small beacon in the landing capsule, poignantly reporting the position of the powerless craft as it sped past its target.

The turmoil generated by this uninterrupted series of failures was, at the least, considerable. In addition to blaming the launch vehicles for the problems they caused, there was considerable distress at JPL over problems with integrating scientific instruments that had little to do with the Moon into Rangers. At Headquarters we reluctantly agreed that trying to do too many things simultaneously was distracting, and it was decided that future Rangers would carry a payload of TV cameras that would concentrate on taking high-resolution pictures before impact. Since the position of the crash site would be controlled, and since the airless environment would not be conducive to propagation of biota, the sterilization of electronic parts would be relaxed. It was further decided that, even though it would delay the program for a year, a comprehensive review and redesign would be performed, along with a more intense testing program, all focused on maximizing the chances of success on the next attempt. In addition to these policy changes, Bud Schurmeier was asked to take charge as the new Project Manager.

Some 9 months later, just before Ranger 6 was to be shipped to the launch site, a company working at Cape Canaveral on a missile guidance system encountered failures in a type of diode that was also used extensively in Ranger circuits. The diodes, tiny units less than half an inch long, employed goldplated elements encapsulated in glass. It was discovered that infinitesimal flakes of gold sometimes peeled off inside the capsules and floated around in zero gravity into positions that short-circuited the diodes. The culprit flakes were of microscopic size and generally made trouble only in zero gravity, but the suspect diodes had to be replaced. It took 3 additional months to replace and retest to make certain that the reworking had not inadvertently caused new problems.

In late January 1964, Ranger 6 and all its systems seemed ready. The launch appeared highly successful, the midcourse maneuver was executed precisely, and it was clear that the spacecraft would impact very close to its selected target site on the Moon. We eagerly awaited camera turn-on and warm-up, due some 15 minutes before impact. What we did not know in those heart-stopping moments was that the cameras could not be turned on, that during the first 2 minutes of launch the rocket had passed through clouds, picking up a charge of static electricity that had arced through the switch. Ranger 6 crashed close to its lunar target with its electronic eyes [109] tightly shut. This failure was a bitter disappointment, the more so because success had seemed so near.

The considerable achievements of the launch vehicle and the spacecraft were almost totally eclipsed by the failure to return pictures, and Ranger critics rose up in numbers to disclaim the value of the effort. Detailed investigations far beyond ordinary failure reviews were instituted by NASA senior administrators and by congressional committees, and people working hard to keep a number of NASA programs moving were called on to explain all the problems from the beginning of Ranger to the present. It is a tribute to the Ranger team that they were able to cope with their own analyses and necessary rework while undergoing intensive management reviews and congressional investigations. For a time there was a question about whether Ranger would be terminated as a complete failure.

A now amusing incident occurred during a congressional review that was symbolic of the times. Bud Schurmeier and I spent two days before a Congressional Oversight Committee describing the spacecraft systems, tests that had been done, and other technical facts relevant to the Ranger ~ failure. During a discussion of the camera turn-on circuit that had apparently failed, I referred several times to the "common" switch that allowed the redundant channel to be activated in case the primary failed. Mr. Karth interrupted me to ask pointedly about our poor judgment that caused us to place a common, garden-variety component in such a sophisticated, multimillion dollar spacecraft.

After a moment of stunned silence, I realized that he had been misled by my use of the term common. The fact was, the switch was a high technology, solid-state device that was affected by the thousands of volts produced by a lightning discharge. It was typical Ranger irony that this necessary single element in an otherwise redundant system had failed; this simple miscommunication with the congressman made me realize how desperate we had become.

Any recounting of Ranger experiences would not be complete without some mention of Bill Cunningham and his involvement through thick and thin, from beginning to end. Bill, christened Newton William Cunningham, had joined Ed Cortright and the three or four others involved in lunar and planetary program activities at NASA Headquarters a few months before I did Although he was hired mainly because of his scientific training in physics and meteorology, Bill developed managerial skills that helped bridge many a chasm while dealing with the tough challenges of Ranger. When I [110] was named to direct lunar and planetary programs in 1961, Bill was named Ranger Program Manager. We had been working side by side; from that time on it was to be more like shoulder to shoulder.

Bill's dedication and loyalty were unmatched. Although I sometimes felt he was too forgiving and informal in his dealings with JPL, I knew that he provided qualities complementary to my more serious and sometimes tyrannical methods. On many occasions he was the "Indian scout" who restored peace and helped assuage the bitterness of JPL personnel who felt oppressed. When Bud Schurmeier became Ranger Project Manager, Bill worked closely with him to restore project relationships with NASA. They were very compatible, both on and off the job, and made my life much easier than it had been.

The three of us were together a lot during the 1960s, some of the time with our backs to the wall defending our project against hardware failures, against scientific critics, against adversary failure review boards, and sometimes against political committees and administrative fault-finders. Our association in countless meetings, at the Cape during launches, on airplanes and in airports, through the misery of six failures and finally the glow of success that came with Rangers 7, 8, and 9 cemented our friendship forever. I have often marveled at my good fortune in surviving the problems with Ranger and remaining as program director. My vulnerability, as "coach" of a losing team that was so much in the spotlight at the time, had made me continually aware of the debt I owed to colleagues like Bill and Bud and to my supportive superiors, particularly Ed Cortright. I kept trying to do the things I thought should be done, and by the grace of God, and with the help of these gifted friends, things worked out.

Ranger 7 was the first spacecraft to return close-up photographic coverage of the surface of the Moon. Aimed at an area chosen by scientific investigators as a candidate site for a manned landing, it provided the first sound evidence to validate the landing gear designs developed for Surveyor and Apollo. Ranger approached the Moon equipped with six TV cameras. A command turned on the two wide-angle cameras for warmup 18 minutes before impact, and four narrow-angle high-resolution cameras warmed up 15 minutes before impact. All cameras functioned perfectly, transmitting 4316 pictures before Ranger 7 crashed. The first picture showed an area of 500 000 square miles and the last, taken at very close range, showed an area 98 by 163 feet. The final images provided a resolution at least a thousand times better than the best pictures taken by Earth telescopes.

[111] Ranger 8, also targeted toward a potential Apollo landing site, and Ranger 9, the last in the series and directed toward lunar highlands, were equally productive missions. Quite suddenly engineers concerned with the design of soft-landers yet to fly and scientists preoccupied with questions about the surface geology of the Moon found themselves almost drowning in a sea of new and superior images. Their varied reactions were perhaps predictable: the engineers found comfort in their existing landing gear designs, and the lunar scientists energetically demonstrated that the new data confirmed their preconceived, often conflicting theories about the Moon's origin.

The wisdom and confidence of those who decided to press on after six failures was borne out by the successes of Rangers 7, 8, and 9 and by the contributions they made to the lunar and planetary programs that followed. In fact, after the dismal failures, the tide decisively turned. The last three Rangers, followed by five of seven Surveyors (attempting vastly more challenging missions) and all five Lunar Orbiters, went on to perform their prescribed missions, and more, with outstanding success. From the perspective of time we can see that those six Ranger failures were not without reward; they taught us to organize and manage missions, to debug imperfect launch vehicles, to decide on and execute midcourse maneuvers, and to design, test, and launch spacecraft with a high probability of success.

Ranger also made incalculable contributions to what would shortly become useful new technologies. The diminutive rocket capsule designed to separate from Rangers 3, 4, and 5 and land on the Moon never got a chance, but the technologies evolved during its development were not wasted.

Although the project had a happy ending, Ranger sometimes reminded me of the ancient folk tale of Scottish King Bruce, repeatedly defeated by his enemies and on the verge of despair. While hiding in a barn, Bruce watched a spider trying to swing from one rafter to another, to spin his web from broad points of support. The spider tried and failed again and again; finally on the seventh try it succeeded in achieving its goal. This so inspired Bruce that he rallied his fugitive soldiers and at last won the victory that had so long eluded him. So it was with Ranger: six sickening failures before fortune smiled on the seventh attempt. For all its failures, Ranger paved the way for future lunar and planetary successes.

 


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Launch of Mariner 2

Launch of Mariner 2


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The Mariner spacecraft family (Top to Bottom, Left to Right: Mariner 2 Venus1962; Mariner 4 Mars 1964; Mariner 5 Venus 1967; Mariner 6 and 7 Mars 1969; Mariner 9 Mars 1971; Mariner 10 Venus and Mercury 1973.

The Mariner spacecraft family (Top to Bottom, Left to Right: Mariner 2 Venus 1962; Mariner 4 Mars 1964; Mariner 5 Venus 1967; Mariner 6 and 7 Mars 1969; Mariner 9 Mars 1971; Mariner 10 Venus and Mercury 1973.


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Launch of Navaho missile in 1957. At the time, this 405 000 pound thrust rocket booster was the most powerful in the world.

Launch of Navaho missile in 1957. At the time, this 405 000 pound thrust rocket booster was the most powerful in the world.

 

Mariner 2 in the systems checkout facility in Hangar AE.

Mariner 2 in the systems checkout facility in Hangar AE.


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Astronaut Charles Conrad, Jr., examines Surveyor 3 on the Moon.

Astronaut Charles Conrad, Jr., examines Surveyor 3 on the Moon. The Apollo 12 Lunar Module landed about 600 feet from the unmanned spacecraft in the Ocean of Storms. Surveyor's TV camera and other instruments were returned to Earth by the astronauts.


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Photos taken by Ranger 9 as the spacecraft approached the Moon prior to impact.

Photos taken by Ranger 9 as the spacecraft approached the Moon prior to impact. The white circle on each photo indicates the point of impact. (a) Altitude, 266 miles; time to impact, 3 minutes and 2 seconds. (b) Altitude, 141 miles; time to impact, 1 minute and 35 seconds. (c) Altitude, 95.5 miles; time to impact, 1 minutes and 4 seconds. (d) Altitude, 65.4 miles; time to impact, 43.9 seconds; area shown, 31.6 by 28.5 miles.


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Mosaic assembled to show the Surveyor 7 surface sampler digging a trench.

Mosaic assembled to show the Surveyor 7 surface sampler digging a trench.


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Surveyor drop test vehicle successfully lands on Earth.

Surveyor drop test vehicle successfully lands on Earth.

 

The world's first view of Earth from the distance of the Moon, taken by Lunar Orbiter 1 during its sixteenth orbit.

The world's first view of Earth from the distance of the Moon, taken by Lunar Orbiter 1 during its sixteenth orbit.


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First closeup photo of crater Copernicus, one of the most prominent features on the face of the Moon. This oblique photo was taken by Lunar Orbiter's telephoto lens from 28.4 miles above the lunar surface and 150 miles due south of the center of the crater.

First closeup photo of crater Copernicus, one of the most prominent features on the face of the Moon. This oblique photo was taken by Lunar Orbiter's telephoto lens from 28.4 miles above the lunar surface and 150 miles due south of the center of the crater.


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Workmen are dwarfed in the massive reflector of the 210-foot Deep Space Network antenna at the Goldstone facility.

Workmen are dwarfed in the massive reflector of the 210-foot Deep Space Network antenna at the Goldstone facility.



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This historic first closeup of Mars was made by hand at JPL as the picture was being radioed to Earth by Mariner 4.

This historic first closeup of Mars was made by hand at JPL as the picture was being radioed to Earth by Mariner 4. It was composed of 40 000 numbers (200 lines with 200 picture elements each) representing different values of grey, from white (0) to black (63). The picture numbers were printed sequentially on a strip of paper tape and then cut into picture lines. The lines of numbers were stapled, side by side, to a board, arbitrary colors were assigned to sets of numbers, and each number was colored with crayons by hand.


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First color photo from the surface of Mars, taken by the Viking 1 lander.

First color photo from the surface of Mars, taken by the Viking 1 lander. The horizon is about 1.8 miles from the camera.

 

View of Jupiter taken by Pioneer 10 from over a million miles away. The Great Red Spot and the shadow of the satellite Io can be seen.

View of Jupiter taken by Pioneer 10 from over a million miles away. The Great Red Spot and the shadow of the satellite Io can be seen.


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Saturn as seen by Voyager 2 from 27 million miles away.

Saturn as seen by Voyager 2 from 27 million miles away.

 

As astronaut in the manned maneuvering unit prepares to dock a satellite to be returned to Earth in the cargo bay of the space shuttle Discovery.

As astronaut in the manned maneuvering unit prepares to dock a satellite to be returned to Earth in the cargo bay of the space shuttle Discovery.


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