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Samos E-1
The Samos E-1 spacecraft (under cover) being serviced prior to mating with the launch vehicle. (credit: National Archives)

A sheep in wolf’s clothing: the Samos E-5 recoverable satellite (part 1)

During the early years of the American space program, while NASA was flying John Glenn and Scott Carpenter and other astronauts around the earth in the Mercury spacecraft, the United States Air Force had its own large, pressurized, recoverable space capsule. Developed in secret, the Samos E-5 spacecraft flew with a reconnaissance camera, but it was clearly an Air Force effort to develop a manned military spacecraft to rival Mercury. Classified for decades, only now is the truth coming out, that the US Air Force hid a military man in space program behind a classified intelligence mission, a sheep in wolf’s clothing.

In the wake of Sputnik, many American military officials simultaneously panicked and salivated at the opening of the space frontier. In particular, US Air Force leaders envisioned developing satellites for a broad range of missions, with their ultimate goal being flying an Air Force officer, or “blue suiter,” into space. President Eisenhower and his aides struggled to hold back over-eager military leaders and prevent them from pursuing many of their ambitious schemes.

Classified for decades, only now is the truth coming out, that the US Air Force hid a military man in space program behind a classified intelligence mission, a sheep in wolf’s clothing.

But the early space age is filled with examples of civilian and military officials being told not to do something and then doing it anyway, in secret. The most notable example was Wernher von Braun’s team in Huntsville losing the decision to develop the first American satellite and then secretly approaching scientists to provide instruments for what ultimately became Explorer 1. When the Air Force lost the manned spaceflight mission in 1958, Air Force officials sought to develop a spacecraft that could be transformed into a manned version with a minimum of additional work. Although some Air Force officials claim that it was Lockheed engineers who were primarily interested in developing a manned spacecraft, Lockheed could not make any major technical decisions concerning the spacecraft without justifying them to the Air Force. Furthermore, plenty of Air Force officers made no secret of their desire for a manned military spacecraft during this period.

The primary Air Force space project prior to Sputnik was the WS-117L reconnaissance satellite program. Officially started in 1956, WS-117L had been starved of funds for years, a fact that had annoyed the dozen or so Air Force officers who directly worked on it and even helped prompt one of them, a young lieutenant named Jack Herther, to leave the service, seeking work in industry. But only a few months after Sputnik the funding floodgates opened and WS-117L began to receive all the money it could use. By early 1958 the Air Force split WS-117L into three main programs named Discoverer, Midas, and Sentry. They each shared common components and launch vehicles, but had different missions.

Discoverer was the first spacecraft scheduled to fly. Although it was officially an engineering project, this was actually a ruse, a cover story for the CORONA reconnaissance satellite. CORONA had received formal approval from President Dwight D. Eisenhower in February 1958. Eisenhower directed that CORONA be run by the same joint CIA-Air Force team that had managed the highly-successful U-2 spyplane program. Richard Bissell, the CIA Deputy Director of Plans, headed this new project. The official cover story was that Discoverer was intended to develop new space technologies and fly mice and monkeys into space to conduct biomedical research. CORONA was a covert program, which meant that unless someone was officially approved, they were not allowed to know that it even existed, and its name never appeared in unclassified documents. In the lingo of the intelligence community, CORONA was “black,” and practically everybody who came in contact with the unclassified Discoverer project thought that it was an innocent technology program, although some suspected otherwise.

CORONA was to be launched atop a converted Thor Intermediate Range Ballistic Missile (IRBM) and utilize a camera system built by the newly-created Boston-based Itek Corporation, where Lieutenant Jack Herther had gone to work after leaving the WS-117L program in disgust at its lack of progress. The CORONA camera took images on 70mm film that was deposited in a small reentry capsule that would parachute to earth and be snagged in midair by a passing aircraft. During flight, the camera and reentry vehicle would be attached to the same spacecraft vehicle that served as a second stage during launch, a vehicle that would eventually be named the Agena and was built by Lockheed.

Midas was an early warning satellite, designed to spot the hot exhaust of Soviet ICBMs and warn of their launch. Although it was to be launched atop the more powerful Atlas rocket, the Midas spacecraft used the same Lockheed-built Agena upper stage as Discoverer/CORONA, relying on this stage for stabilization and power while in orbit. Unlike CORONA, Midas had no CIA involvement and was solely an Air Force program, managed by a special satellite office inside the Air Force’s Ballistic Missile Division, or BMD, in Los Angeles. BMD had become a large organization with an important job: developing the Atlas and Titan ICBMs.

The third and largest component of WS-117L, Sentry, was also an entirely Air Force project and like Midas used the Atlas rocket and Lockheed Agena upper stage. Despite the existence of CORONA, Sentry was in many ways the primary American reconnaissance effort and the direct descendant of the original WS-117L program. It was the biggest space project in the satellite office at BMD. To everyone, including its managers, CORONA was only an “interim” program until the more ambitious and complex Sentry spacecraft entered service, which was supposed to happen in 1960 or 1961. Whereas before Sputnik WS-117L program managers had begged for funds, Sentry’s program managers soon had all the money they needed, a budget that jumped from $10 million in Fiscal Year 1958 to $159.5 million the following year—although it came with exasperating bureaucratic strings attached. Unlike CORONA, Sentry was an acknowledged, overt program. It was “white,” or at least a shade of gray: Most details about Sentry were classified, but its existence and reconnaissance purpose were openly acknowledged in press releases.

The bureaucratic strings attached to the Sentry and Midas programs were pulled by ARPA, the Advanced Research Projects Agency. President Eisenhower had created ARPA in the wake of Sputnik as an independent Department of Defense agency to oversee military space programs managed by the Army, Navy, and Air Force. Based in Washington, ARPA officials controlled the Sentry and Midas purse strings and therefore approved all major decisions made by the Air Force satellite office at BMD in Los Angeles. Throughout 1958 and most of 1959, they asserted this authority to the perpetual annoyance of the Air Staff in the Pentagon—the Air Force’s senior military leadership—and to the program managers at Ballistic Missile Division. ARPA was not very popular with the Air Force.

Lockheed’s ambitions

For several years, in addition to the WS-117L reconnaissance program, the Air Force was also funding contractor studies for a Man In Space Soonest, or MISS, program to place an Air Force pilot in space in a relatively short time. Several companies had been doing research on this subject, although it was low-key and the service did not push its development until after Sputnik. In January 1958, Lockheed submitted a proposal for a large, cone-shaped manned space capsule, nine feet (2.7 meters) in diameter and 14 feet (4.3 meters) long using an Agena upper stage, which was only slightly more than half the capsule’s diameter. The spacecraft/rocket combination would have been a mushroom head shape during launch, which was something that early satellite designers sought to avoid because of concerns that it would present aerodynamic problems in flight. The Air Force did not approve the actual production of a manned spacecraft at this time.

The reason that Lockheed’s manned Sentry proposal did not get a warmer reception at the Air Force was that the overall “man-in-space” program was in considerable flux between the spring and summer 1958.

In late April 1958, Lockheed proposed a manned “aero-medical recovery configuration” Sentry vehicle. It would place a man inside a cramped space capsule atop an upgraded Agena vehicle. This time Lockheed’s engineers kept the capsule the same diameter as the Agena—five feet, or 60 inches (1.5 meters). Because of the tight space, the astronaut would have to sit in a crouching position with his feet tucked up underneath him, unlike the sitting position ultimately adopted by operational American spacecraft, where the feet were level with the knees. The spacecraft would be launched atop an Atlas rocket and use the Agena for stabilization and power. Solid-propellant retrorockets mounted at the base of the Agena would be used to decelerate the entire spacecraft before separating the recoverable capsule.

Lockheed’s proposed manned Sentry vehicle was to be simply the next step in the aero-medical research that the Air Force hoped to conduct as part of the Discoverer program. Discoverer already included at least one small primate flight, although the leaders of the CORONA program viewed that flight solely as a cover for their reconnaissance mission. This new Lockheed proposal for a manned Sentry vehicle, like the earlier January proposal, was also not approved at this time.

The reason that Lockheed’s manned Sentry proposal did not get a warmer reception at the Air Force was that the overall “man-in-space” program was in considerable flux between the spring and summer 1958. The Air Force effort lacked focus, and officers were more interested in the winged Dyna-Soar spaceplane and advanced manned space projects than they were in the initial manned ballistic capsule, which many felt was boring. Various aerospace engineers were also unsure about even basic design criteria for such a spacecraft, such as which configuration would be best for reentry. In fact, the Atlas ICBM had only about a 75% success rate, and the ICBM office saw no need to improve its reliability. This led the space program officials to evaluate other rockets for launching a vehicle into space, despite the fact that they would be unavailable until after the Atlas. With so many unknowns, and a general lack of focus on a ballistic capsule, the Air Force was unwilling to commit to any specific proposal.

A Mann stereo-comparator used to determine dimensions from stereo satellite photos. (credit: CIA)

The limits of readout

Throughout 1958 the design for the Sentry reconnaissance program took firmer shape. Unlike CORONA or Midas, Sentry consisted of several different payloads, including both visual and electronic intelligence sensors. By late 1958 the Air Force was developing two different Sentry camera systems, originally referred to as the “Pioneer” and “Advanced” cameras, but soon known as the E-1 and E-2, both manufactured by the Eastman Kodak Company in Rochester, New York. The Air Force was also studying the E-3, a more advanced system. The designation “E” derived from an early administrative decision to label each major satellite subsystem with a letter, starting with A: A was airframe, B was propulsion, and so on. “E” simply designated a camera system. The E-1 was primarily a crude demonstration camera, able to see objects on the ground—known as “ground resolution”—around 100 feet on a side (roughly 30 meters). The E-1 camera had a six-inch (15 cm) focal length, the distance from the aperture of the camera to the focal point—the larger the focal length, the more powerful the camera. E-1’s main job was to prove that the spacecraft and the ground system would work.

The E-2, with a 36-inch (91 cm) focal length, was more refined, theoretically capable of spotting objects as small as 20 feet wide (approximately six meters) on the ground. The satellite would take approximately five minutes to pass over its target, taking as many photographs as possible in that short time. The E-2 could achieve stereo photography by slewing its camera forward and back along its ground track, taking pictures of a target from two different angles. This provided photo-interpreters with a method of accurately measuring the targets. But the camera could not look far to either side of the ground track, which limited the amount of territory that the satellite could cover during each orbit to that directly below the spacecraft.

The E-1 and E-2 both used a technique called film-readout. The film would be exposed and then as it moved through the system it would be pressed up against another film called a “web” and coated with developer and a fixing agent. After the film had dried out, it would then be scanned with a light beam and the light and dark spots on the film converted to electrical impulses that would be transmitted to the ground over a 6 megahertz transmitter. The benefit of this approach was that imagery could be sent to the ground within hours, and the satellite could stay in orbit for weeks. But this came at a price: the total number of images that could be transmitted was small, only a few dozen per satellite per day. In fact, several photographs during each pass over the Soviet Union would have to be discarded because there was insufficient time to transmit them to the ground when they were in sight of a ground station in the United States. In order to compensate for this low number of images, the Air Force would have to orbit several satellites simultaneously, dramatically increasing the number of ground stations to control them as well as the overall cost of the project.

The E-3 was still only a paper concept in 1958, although it would have had a more powerful camera than the E-2. But the major difference between the E-3 and the other cameras was that the E-3 used an exotic electrostatic tape system to store its images in order to improve transmission time. E-3 was more popular with ARPA’s leadership than it was with the Air Force officers at Ballistic Missile Division responsible for managing the satellite effort. The ARPA officials had less faith in the proven, but limited, film readout approach than the satellite managers at Ballistic Missile Division, and felt that the E-3’s untested electrostatic tape offered a better solution, promising to return more images per satellite than the E-2.

In January 1959 NASA selected McDonnell Aircraft to build the Mercury spacecraft. Lockheed was apparently out of the running to build a manned spacecraft.

No matter what camera was used, E-1, E-2, and E-3 would all photograph relatively small areas below the satellite, which pointed nose down at the earth, stabilized by gravity. This was the primary spacecraft stabilization mode that Lieutenant Jack Herther had been responsible for overseeing in his capacity as head of the guidance and control part of WS-117L from 1955 until 1957. Herther, however, was never convinced that this stabilization system would be completely successful.

In contrast to E-1, E-2, and E-3, the CIA-directed CORONA system returned all of its film to the ground in a small capsule. Photo-interpreters could not look at an image immediately after it was taken—they had to wait up to several days—but they had many more images to look at. A CORONA camera could image up to 1.5 million square miles (3.9 million square kilometers) of the Soviet Union in a single day, compared to only 64,000 square miles (166,000 square kilometers) for the Sentry E-2.

In late 1957 Air Force reconnaissance advisors at the civilian RAND Corporation in the suburbs of Los Angeles had suggested that a recoverable capsule could be used for larger cameras, bigger than that soon chosen for the CORONA, and perhaps as big as 120 inches (3 meters) focal length. But for over a year following Sputnik, the Air Force satellite office ignored this suggestion and CORONA, with its 24-inch (61-cm) focal length camera, was the only approved recoverable reconnaissance program.

Sentry Man In Space

In early 1958 ARPA and Air Force officials started discussing cooperation on a manned spacecraft called Man-In-Space, or MIS for short—the “Soonest” having been dropped from the name. But when it became clear in the summer of 1958 that a new civilian space agency would be created out of the National Advisory Committee on Aeronautics (NACA), officials at the Pentagon and White House agreed that this civilian agency would be responsible for the manned spacecraft program. By August 1958, NACA had issued a preliminary definition of the civilian spacecraft, which it soon named Mercury. By October, the newly-created NASA solicited bids from several dozen companies to build the Mercury spacecraft.

In August 1958, Lockheed submitted to the Air Force a revised “Sentry Man In Space” proposal in the form of several briefing slides. The space capsule would weigh 3,072 pounds (1,394 kg), flying atop a 7,928-pound (3,596-kilogram) Agena upper stage. This was identical to Lockheed’s April proposal and would have used two solid propellant retrorockets providing 16,000 pounds (71,200 newtons) of thrust for four seconds, a maximum acceleration of 4.5 g’s. Lockheed proposed a manned capsule 84 inches (213 cm) long and 60 inches (152 cm) wide, using a “blunt body” design for reentry. One briefing slide proposed a heat sink reentry shield whereas another proposed a “refrose ablation material.” The proposal did not include an emergency escape system for lifting the capsule clear of an exploding rocket.

Although decision makers in Washington had pretty much decided that NASA would develop the manned spacecraft, Lockheed engineers in Sunnyvale, California were clearly looking to expand their company’s business. In August 1958 they also proposed that the Air Force develop a data relay satellite, a weather satellite, and upgraded versions of the Agena upper stage with increased diameters and even an additional upper stage atop the Atlas-Agena. None of these proposals were adopted by the Air Force at that time, but clearly the company wanted to expand beyond reconnaissance satellites.

Only a few months later Lockheed entered NASA’s manned spacecraft contract competition. Lockheed’s Mercury spacecraft proposal looked like NASA’s suggested configuration, a shortened cone, or “frustum,” topped by a cylinder containing the parachutes and recovery equipment. It would not use an Agena upper stage to reach orbit or for on-orbit stabilization and power, and because it sat directly atop the fatter Atlas rocket and not the thinner Agena, it could have a larger diameter, up to 80 inches (203 cm) as opposed to the 60 inches (152 cm) of Sentry MIS. The August Sentry MIS proposal was apparently little more than a few presentation slides for the Air Force, whereas the company’s December Mercury contract submission was a detailed proposal. The two proposals, although produced only a few months apart and undoubtedly by many of the same people, bore little relationship to each other.

In January 1959 NASA selected McDonnell Aircraft to build the Mercury spacecraft. Lockheed was apparently out of the running to build a manned spacecraft. But despite the fact that they had no formal approval of a military manned space program, Air Force officials did not completely abandon the idea of developing their own manned spacecraft, and neither did Lockheed’s engineers.

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