On October 28, 1969, barely three months after Apollo 11 carried the first astronauts to land on the moon, The Boeing Company wins a $19.6 million contract to design and build a motorized "moon buggy" that will give future astronauts far greater mobility on the lunar surface. Science-fiction writers and far-sighted scientists and engineers have been speculating about what such a vehicle would look like since early in the twentieth century, but it will fall to Boeing to move the concept from speculation to reality. The company does so in the remarkably short span of 17 months. Despite running massively over budget, the first fully operational lunar dune buggy, Rover 1, is ready to fly to the moon when the Apollo 15 mission blasts off from NASA's Kennedy Space Center in Florida atop a Saturn V rocket on the morning of July 26, 1971. On board are astronauts David R. Scott (b. 1932), Alfred M. Worden (b. 1932), and James B. Irwin (1930-1991), and folded away in a compartment on the side of the lunar lander is Boeing's Lunar Roving Vehicle. On July 30, 1971, Scott and Irwin will become the first humans to traverse the lunar surface on wheels, gleefully kicking up clouds of moon dust as they range far from their landing site.
A Long Legacy
William E. Boeing (1881-1956) was an early aviation visionary, but when he formed his first airplane company in 1916 he could hardly have imagined that one day astronauts would be scooting around the lunar surface in a strange, dune-buggy-like device with his name on it. Yet in 1969, 50 years after Boeing won fame by delivering the first international airmail between Vancouver B.C. and Seattle and 13 years after his death, the company he started was picked to build a wheeled vehicle that would allow lunar astronauts to drive on the moon.
The Boeing Company is not yet (2012) 100 years old, but since its founding it has designed and built everything from early airplanes that took more nerve than skill to fly, huge passenger jetliners that revolutionized air travel, warplanes of incredible lethality, and highly complex machines designed to perform flawlessly in the frigid vacuum of space. Boeing-made military equipment has played a pivotal role in every major conflict the U.S. has been involved in since the end of World War I. By 1969 Boeing was a recognized leader in nearly every aspects of aviation and spaceflight, but its experience in designing and building vehicles bound to the ground was virtually nil.
Flights of Fancy
Humans no doubt have dreamed of traveling to the moon since early Homo sapiens gazed at Earth's brightest nighttime companion. Written tales of lunar excursions go back at least as far as the second century C.E., when Antonius Diogenes put explorers on the moon in his Of Wonderful Things Beyond Thule, and Lucius of Samosata told of earthlings brokering a truce between the warring inhabitants of the sun and the moon in his parody, A True Story. The seventeenth century saw a flowering of such tales, with contributions by a famed scientist (Johannes Kepler’s Somnium, 1630s), a noted novelist (Cyrano de Bergerac's The Other World: The Societies and Governments of the Moon, 1656), and a well-known theologian (Bishop Francis Godwin's The Man in the Moon, 1638). Daniel Defoe (ca. 1659-1731), Washington Irving (1783-1859), and Edgar Allan Poe (1808-1849) all put men on the moon, and the infamous fabulist Baron Münchhausen (1720-1797) was, of course, rumored to have made the trip himself.
It was in the late nineteenth century that writers began to describe moon travel in something resembling scientific terms. In 1865, French author Jules Verne (1828-1905) published De la Terre a la Lune (From Earth to the Moon), followed in 1871 by his Autour de la Lune (Round the Moon). In 1901 English author H. G. Welles (1866-1946) wrote The First Men on the Moon. After that the floodgates were open, and science fiction grew to become one of literature's most popular (and most maligned) genres. Soon writing about travel to the nearby moon was seen as rather tame, and sci-fi writers carried their readers ever further, to the planets, to the stars, to other dimensions, even through time, and in both directions.
Moon travel was also an early subject of motion pictures. In 1902 French filmmaker Georges Méliès (1861-1938) directed the first known science-fiction movie, Le Voyage dans la lune (Trip to the Moon). Many will recall the iconic scene from this 11-minute movie when the French spacecraft, shot from a giant cannon, strikes the Man in the Moon squarely in his right eye. When Méliès's adventuresome explorers are forced to flee the warlike Senelites, they do so by the simple expedient of pushing their bullet-shaped rocket off a lunar cliff, from where it falls safely into one of Earth's oceans.
Ideas, Good and Not So Good
Having successfully put men on the moon through a variety of contrivances, science-fiction writers next had to figure out how these earthlings were to move around the lunar surface. By the early twentieth century they were imagining various vehicles for this purpose, and before the century was too far along they were joined in the effort by a handful of actual scientists.
Some of these early concepts for lunar exploration had elements of practicality; others were pure whimsy. One of the first, by Polish science-fiction writer Jerszy Zulawski (1874-1915), fell into the first category. His rover design appeared as an illustration in his 1901 tale On the Silver Globe and featured full pressurization, electrical power, and two forms or propulsion: large, spoked wheels and "feet" mounted on a triangular framework that would be used to climb up mountains or travel over rough terrain. Zulawski's invention, like Boeing's real lunar rover, had a top speed of about 10 miles per hour.
A Russian author and scientist, Konstantin Tsiolkovsky (1857-1935), is often called "the father of modern rocketry" (Lethbridge, "Konstantin Eduardovitch Tsiolkovsky"). He spent a lifetime mulling over how mankind could travel to space and explore other worlds, and in his 1918 book Outside the Earth he posited a combined lunar lander/rover that incorporated several features that would be included in actual machines many decades later.
Hugo Gernsback (1884-1967) emigrated from Luxembourg to America in 1904 and became a leading writer and publisher of science fiction. It is for him that the prestigious Hugo Award for science-fiction writing is named, and he published the first popular American science-fiction magazine, Amazing Stories. Gernsback imagined at least two different lunar rovers, one as early at 1915 and one nearly 50 years later, in 1961. The latter, dubbed the Homomobile, seemed a reasonably practical device, with tank treads for movement, mechanical arms, and a folding sunshade.
Other early ideas were considerably less practical. American science-fiction writer Homer Eon Flint (1888-1924) died quite young (and mysteriously), but not before writing Out of the Moon, a space-travel novel featuring a two-legged mechanical rover that strode across the lunar surface like some huge and ungainly bird.
Russia Leads the Way
Just getting even a small object off the face of the earth and into orbit proved difficult and took until 1957, when the Soviet Union launched Sputnik 1, a tiny metal sphere whose faint radio beeps sparked in many the fear of an existential threat to the non-Communist world. The Soviets followed this triumph four years later with the first manned orbital flight, sending cosmonaut Yuri Gagarin (1934-1968) aloft for a single, 108-minute circuit of the earth on April 12, 1961.The USSR scored another coup in August 1961, when cosmonaut Gherman Titov (1935-2000) orbited for a full 24 hours.
During the four years between the Sputnik flight and that of Titov, the American public was forced to endure a seemingly endless stream of televised pictures of unmanned American rockets failing to ignite, blowing up on the launch pad, blowing up somewhere between the launch pad and where they were meant to go, or successfully leaving the launch pad and then disappearing, never to be heard from again. There was a good reason these early American attempts at launching rockets were all aimed over the ocean. Nonetheless, little more than a month after Gagarin's epic flight, President John F. Kennedy (1917-1963), in a speech to Congress on May 25, 1961, made the now-famous statement that would set America on a course for the moon:
"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 the Earth. No single space project ... will be more exciting, or more impressive to mankind, or more important ... and none will be so difficult or expensive to accomplish … . ("Special Message to the Congress on Urgent National Needs, May 25, 1961).
Kennedy was right on all counts, and despite American rocketry's frequent and embarrassingly public failures, the U.S. actually was not too far behind the Soviet Union in what would become known as the "space race." Two U.S. astronauts, Alan Shepard (1923-1998) and Gus Grissom (1926-1967), went on suborbital rocket rides within months of Gagarin's triumph, and John Glenn (1921-2016) was hurled into space for three orbits in February 1962. But success was never taken for granted -- NASA officials were so uncertain of their ability to bring Glenn safely back to where they intended that he was given a phrase book of friendly greetings in various aboriginal languages lest he land in some remote and unmapped place.
Why a Rover?
The decision to actually put a rover on the moon had a strong "wow" factor, but there were practical reasons behind it. Most of the astronauts' explorations on the lunar surface were to be geological, and it was crucial that they be able to take samples of lunar rocks and soil from diverse locations for transport back to Earth. This entailed the use of tools, such as shovels, tongs, and small pick-axes, and in the low gravity of the moon these could easily be carried some distance. But the problem was getting back to the landing module with both tools and samples. That was simply too much stuff to carry, requiring either fewer samples or the abandonment of tools at the end of the each gathering expedition. As each mission included several such forays, this would have required several sets of tools. On one of the early Apollo landings the astronauts used a small hand-cart, but this proved a poor solution in the fine-grained lunar soil.
Another factor supporting the use of a rover was the significantly greater range it would give the astronauts on the lunar surface. Studies had established just how far an astronaut dressed in a bulky spacesuit could wander from the landing module and still have enough strength, energy, and life support to make the return trip, with a substantial margin of safety. A lunar rover would more than double this distance. Even if it broke down at the maximum safe distance from the lander, the astronauts, facing only a one-way trip on foot, could abandon their ride and moon-hop back "home." (The term "moon hopping" was coined to describe the half-walk, half-hop method that astronauts found most effective for moving around on foot in the moon's low gravity.)
In the 1950s, scientists began thinking seriously about sending men to the moon, and providing mobility while there was an early consideration. In 1951, the visionary science-fiction author Arthur C. Clarke (1917-2008), who was also a trained physicist and mathematician, described his conception of lunar rovers:
"Pressurized vehicles with large balloon tires … . Their motors would be electric, operated by storage batteries, or else turbines, driven by reacting rocket fuels … ." (Arthur C. Clarke, The Exploration of Space).
In 1953, Dr. Wernher von Braun (1912-1977), a former Nazi rocket scientist who went on to lead the Apollo program, put forward a plan for a moon rover that would be propelled by hydrogen-peroxide-driven steam turbines, a technology he had investigated while developing the deadly German V-2 rocket during World War II. A year later, another German scientist, Hermann Oberth (1894-1989), sketched out a rather far-fetched plan for a rover that would speed across the lunar surface at 90 miles per hour!
Feasible or fanciful, these early proposals for moon rovers had one thing in common -- passengers rode in an enclosed and pressurized chamber of some sort. This dictated that astronauts would either have to interact with the lunar world remotely, with mechanical arms, or would need some convenient method of repeatedly getting in and out of their chamber to explore. Both options were clumsy and complex, and the men and women of NASA, Boeing, and other involved companies, after a few false starts, were to come up with a better idea.
Make It So
The original official plans for a moon vehicle came from the military and were part of a 1959 study by the U.S. Army Ordnance Missile Command for a manned base on the moon. Known as Project Horizon, it included a proposal by the army's Transportation Corps for a moon vehicle that followed the ideas of early proponents by specifying a pressurized passenger cabin.
In 1960, the moon-rover study and many of its participants were transferred to the newly created Marshall Space Flight Center in Huntsville, Alabama. The initial formal studies for building a lunar-surface vehicle began in September 1962, when NASA's Office of Manned Space Flight contracted with the Grumman Aircraft Engineering Corporation and Northrup Space Laboratories to define and design a "Lunar Logistic System" ("Lunar Roving Vehicle: Historic Origins, Development, and Deployment"). These studies again produced designs for a rover with an enclosed and pressurized crew compartment.
In 1964, the Marshall Center, in a program called the Apollo Logistics Support System, contracted separately with The Boeing Company and the Bendix Corporation to develop designs for a vehicle called MOLAB (for "mobile laboratory") that could sustain two astronauts on the lunar surface for 14 days. Once more, the space program administrators were stuck in a "pressurized crew compartment" mindset, with no apparent thought given to the idea of a rover in which the astronauts would be protected from the harsh lunar environment only by their space suits.
Both companies presented their results to NASA within six months. Boeing's proposed rover was nearly 38 feet long and had two articulated sections, six woven-wire wheels, and a range of only about 500 feet. Bendix's proposed rover was nearly as large, but boasted a range of over 90 miles. One could thus go much farther than necessary and the other not nearly far enough. Both designs bore scant resemblance to what was eventually built, and the disparity in their distance abilities was indicative of the still-unsettled question of precisely what a moon rover should be designed to accomplish.
The Boeing proposal did have one significant design concept that would be adopted in the actual rover some years later -- each of its six wheels was powered by an individual motor. But even here there were substantial differences between what was proposed and what was eventually built. Boeing's 1964 design called for the wheels to be powered by liquid oxygen/liquid hydrogen fuel cells. In the rover as it was eventually built, much simpler electric motors were used.
The MOLAB program was later cancelled, but not before the two companies were directed to develop both smaller rovers, dubbed Local Scientific Survey Modules, and "stripped down" versions of their rather massive machines, called Mobility Test Articles. Each design iteration refined both the questions to be asked about travel on the moon's surface and possible solutions. Eventually, the idea of "mobile laboratories" was set aside in favor of simply providing astronauts a vehicle that could safely and reliably extend the range of their explorations.
Boeing Takes the Prize
Apollo 11 put Neil Armstrong (1930-2012) and Buzz Aldrin (b. 1930) on the moon on July 20, 1969. This was followed by a successful Apollo 12 mission, an aborted and nearly disastrous Apollo 13 mission, and, in February 1971, a successful Apollo 14 mission. In each of the successful moon landings, two astronauts encased in bulky space suits moved stiffly around the lunar surface in close proximity to their landing module. These voyages were all triumphs of technology, but their scientific value was limited by the relative immobility of the men who were put on the moon at such great cost.
Even before Apollo 11 blasted off, Werner von Braun was looking beyond these early missions. On April 7, 1969, he established at the Marshall Center a Lunar Roving Task Team, which reviewed the earlier proposals and designs and determined how the space agency should proceed. On October 28, 1969, Boeing, with the advantage gained through its experience in the MOLAB program, was awarded the contract to design and build a lunar rover that, if successful, would be used on Apollo 15, 16, and 17 (the original plan was to use the rover on four moon missions, but Apollo 18, together with Apollo 19 and 20, were subsequently cancelled, due mostly to cost concerns). The estimated cost of the project was $19 million, but the Boeing contract was awarded on a cost-plus-incentive-fee basis.
Scaling Back and Forging Ahead
Almost all of the earlier rover designs had been premised on the use of two launch vehicles, one to carry astronauts to the moon and a second to transport a large mobile laboratory. By the time Boeing was awarded the contract to build a rover, these plans had been abandoned due to concerns about complexity, weight, and cost. Instead, the final contract called for the design and construction of a much smaller vehicle, based loosely on the famous World War II jeep and the recreational dune buggies that were a post-war outgrowth of those hardy war wagons. Gone was any thought of a pressurized cabin; the new rover would have just one main purpose, and that was to allow astronauts to get as far away from their landing module as safety would permit. Using the rover, they could collect soil and rock samples some distance from the landing site and carry themselves, their collections, and their tools back to the Lunar Excursion Module, or LEM, in relative comfort and safety. The Marshall Center built a Lunar Surface Simulator at its Huntsville facility for testing rover designs, recreating as nearly as possible the soil textures and land contours of the lunar surface. Successive test models could be driven here on earth in terrain conditions that could at best approximate those on the moon.
Boeing conducted its rover research and development both at Huntsville and at its facility in Kent, Washington. General Motors' Delco Electronics Division was selected to design and built the rover's electrical components. The schedule was tight -- the flight of Apollo 15 was scheduled for late July, 1971, just 22 months after the rover contract was awarded. Given the need for extensive testing before a vehicle could be trusted to carry astronauts safely on the moon, Boeing would need to have a working model ready in a significantly shorter time than that, and the contract specified that such a model must be completed no later than April 1971. Critical-path milestones included a preliminary design review within the first 10 weeks and final design approval within 22 weeks of the awarding of the contract. The contract had a long list of very specific requirements, which included the following:
- The rover was to be a four-wheeled vehicle, with each wheel individually powered by a battery-fed electric motor;
- It was to be capable of being operated manually by a single astronaut;
- It was to weigh no more than 400 pounds, and was to be capable of carrying 100 pounds of science experiments, 100 pounds of lunar samples, and two suited astronauts weighing 370 pounds each;
- It was to have the capacity to perform four 30-kilometer (18.6-mile) lunar traverses in a 78-hour period;
- It was to have sufficient electrical power to operate for a minimum of 78 hours;
- It was to be capable of maintaining a sustained velocity of 16 kilometers per hour (9.94 mph) on a smooth lunar surface;
- It was to be capable of climbing and descending a maximum slope of 25 degrees from horizontal;
- It had to have sufficient redundancy that no single-point failure would render it inoperable and no second failure would endanger the crew;
- It had to have a turning radius of approximately one vehicle length and be capable of traveling in reverse;
- It had to be able to surmount 12-inch-high obstacles and safely cross 28-inch diameter craters;
Perhaps most critical, the final design had to be collapsible and capable of being carried in a compartment mounted to the side of the ascent stage of the Lunar Excursion Module that would carry astronauts to the lunar surface. As described in one account of the rover's history:
"the folded rover would have a volume approximately that of the familiar Volkswagen "Beetle," but it would have to unfold into a vehicle with little less than the volume of a Mercedes Benz 190" ("Lunar Roving Vehicle: Historic Origins, Development, and Deployment", p. 6).
The project was an enormous challenge, but Boeing and its subcontractors went immediately to work. The preliminary design review took place on schedule in mid-January, 1970 and the final design review occurred exactly six months later, in mid-June. After intense scrutiny, the final design was approved, and Boeing could move on to actually building a rover that would be carried to the moon the following year.
Boeing did most of the manufacturing and assembly of the lunar rover at its facility in Kent. A total of eight test models that would never go to the moon were built. These included a full-scale mockup to insure that the design would comfortably "fit" the astronauts in their bulky lunar spacesuits and life-support backpacks; a mobility-design unit to test all of the rovers movement and control mechanisms; two one-sixth-weight versions (approximating the lower gravity on the moon) to test out the rover-deployment strategy; a vibration-test unit to make sure the final product could withstand the violence of launch and the stresses of space flight; and one fully functional, full-size, full-weight rover for astronaut training.
On March 10, 1971, two weeks ahead of schedule, the first lunar rover that was to travel to the moon was delivered to NASA. To no one's great surprise, it had cost almost precisely twice the original estimate, coming in at $38 million. But it was a wonder of design and engineering -- a fully functional vehicle that could be folded up, bolted to the side of a lunar lander, flown to the moon, unfolded, and driven by astronauts to places they could never reach on foot. With launch day just over four months away, all those who worked so hard to create this marvel could only wait to see if their labors and their ingenuity would be rewarded with success.
To the Moon!
Apollo 15 blasted off on schedule 9:34 a.m. EST (13:34:00 Greenwich Mean Time) on July 26, 1971, with David R. Scott, Alfred M. Worden, and James B. Irwin on board. After achieving moon orbit, on July 30 the lunar module carrying Scott and Irwin separated from the command module. Almost exactly four hours later it set gently down on the surface of the moon in an area called the Hadley-Apennine region. Less than an hour after landing, Scott was poking his head out of the lander, taking photographs. The astronauts took a long rest period, got themselves organized, then left the landing module and set foot on the moon about 13 hours after landing.
After the quick collection of some soil and rock samples in case the mission had to be aborted prematurely, the moment everyone was waiting for came. At 14.05.33 GMT, or about 9:00 a.m. Eastern Standard Time, the rover deployed flawlessly from its compartment. Within an hour and a half, Irwin and Scott set off on what would be the first of three motorized jaunts across the lunar surface, during which the rover functioned precisely as intended.
In terms of geology, this was by far the most productive of the lunar missions to date. The astronauts were able to gather 167 pounds of soil and rock from the dark plains (maria) near the landing site, from the Apennine highlands, and from an area along Hadley Rille, a long, narrow winding valley. The latter two areas could not have been reached without the rover, which averaged about six miles per hour, hitting a top speed of seven and a half mph on level terrain. The total distance it traveled during the mission was a little over 17.3 miles.
On August 2, 1971, after three days on the lunar surface, the astronauts transferred their priceless cargo of moon matter to the lunar module. At about 12:30 p.m. EST they left the surface of the moon to rendezvous with the Apollo command module, leaving the remarkable Lunar Rover 1 behind. It had done everything that was asked of it, and more. With it, the astronauts were able to do three times the work done on the three earlier moon landings. The little car, which became affectionately known as the "moon buggy," operated without a hitch in a temperatures that ranged from minus 200 to plus 200 degrees Fahrenheit and in conditions that nothing on Earth could reasonably approximate. It was truly a marvelous display of human inventiveness and ingenuity. It was also, for lack of a better word, fun.
These were the rover's primary specifications and features:
- It was just over 10 feet long and had a had a 7.5-foot wheelbase;
- The width to the center of the tires was six feet, and it was 44.8 inches high, not counting the antenna dish;
- It weighed about 460 pounds (Earth weight) when deployed on the moon and could carry more than twice that much. The astronauts and their portable life support systems alone weighed nearly 800 pounds
- Each wheel was individually powered by a quarter-horsepower electric motor, giving the rover a tiny total of one horsepower;
- The front and rear wheels had separate steering systems, providing both redundancy and increased mobility. A failed system could be disconnected and the rover operated with the remaining system with no great loss of effectiveness;
- All the rover's systems were powered by two 36-volt batteries, but it could operate fully with just one;
- A T-shaped hand controller was located between the two seats and could be operated by either astronaut. It controlled the four drive motors, two steering motors, and the brakes. The rover went in whatever direction the stick was moved, and pulling it backwards put on the brakes. Flipping a switch on the handle before pulling it back would put the rover into reverse, and pulling the handle all the way back activated a parking brake.
- It was designed to operate for 78 hours and to make several exploration sorties up to a cumulative distance of 40 miles. However, the limitations of the astronauts' life-support systems restricted the rover's single-trip safe range to a radius of about six miles from the lunar module, a distance that would permit them to walk back to the lander in the event the rover became immobilized.
"Quite a Machine"
The Boeing Company eventually made four lunar rovers for NASA, each intended for work on the moon. When the space agency cancelled the last three planned missions, the fourth rover was used for spare parts.
On Apollo 16, astronauts John Young (b. 1930) and Charles Duke (b. 1935) landed in terrain that was much more rugged than expected. Yet, thanks to the rover, they were able to range over a wide area and gather samples of breccia, a type of aggregate rock left by meteorite bombardment. Young later estimated that without the rover, he and Duke would have been able to accomplish only about 5 percent of what they actually did accomplish.
The Apollo 17 flight took Eugene Cernan (b. 1934) and Harrison Schmitt (b. 1935) to the lunar surface. Schmitt was the first academically trained geologist to visit the moon, and he took full advantage of the mobility provided by the rover. The astronauts covered nearly 22 miles over three excursions, more than the previous two rover missions. They also set a speed record of a little over 11 miles per hour and brought back nearly 250 pounds of lunar samples, also a record. During one of the drives, Cernan exuberantly radioed to Mission Control, "This is quite a machine, I tell you" ("A Brief History of the Lunar Roving Vehicle").
The lunar rovers led to several "spin-off" products for civilian and military use, including such things as robotic vehicles and advanced motorized wheelchairs. The multi-purpose "joystick" that controlled the rover was later adapted for computer games. A variation of it was also developed to permit those without the use of their legs to drive without the need for extensive modifications to the vehicle.
The Boeing Company went on to produce successive generations of commercial and military aircraft. Of the several aerospace companies that worked on the Saturn V rocket, the Command Module, the Lunar Module, and the Lunar Excursion Module, all but one (Grumman Aircraft Engineering) would later become part of Boeing as it entered the twenty-first century.
After all the rover missions were completed, astronaut/geologist Harrison Schmitt summed up the little buggy's impact on the Apollo program and the quest for knowledge about Earth's closes neighbor:
"Without [the rover], the major scientific discoveries of Apollo 15, 16, and 17 would not have been possible, and our current understanding of lunar evolution would not have been possible" ("Lunar Roving Vehicle: Historical Origins, Development and Deployment").
As for the Apollo program of which the rover was such a critical component, Jim Lovell, the commander of the ill-fated Apollo 13 missions, was perhaps most eloquent:
"We learned a lot about the Moon, but what we really learned was about the Earth. The fact that just from the distance of the Moon, you can put your thumb up, and you can hide the Earth behind your thumb. Everything that you have ever known, your loved ones, your business, the problems of the Earth itself, all behind your thumb. And how insignificant we really all are. But then how fortunate we are to have this body, and to be able to enjoy living here amongst the beauty of the Earth itself" ("Memorable Quotes for Apollo 13").