by Dwayne Day
Discoverer III was the first mission to carry animals—four black mice—as part of the cover story for the CORONA program. A launch attempt in late May was aborted when telemetry indicated a lack of mice activity. It was thought that the mice were asleep. When a technician banged on the side of the vehicle and failed to wake them, the launch was aborted. In fact, the mice had consumed the krylon coating on their cages and died.23
The second launch attempt a few days later was aborted when a humidity sensor in the capsule reported a 100% relative humidity level. The mice had urinated on the sensor, causing the faulty readings. The vehicle was dried out and readied for another launch attempted on June 3. During vehicle separation the Agena apparently fired straight down, plunging the Agena, payload, and mice into the Pacific Ocean. The mishap resulted in complaints from both a British humane association and several American newspapers, which were also incensed about the death of the monkey Able, who had perished after a joint Army-Navy suborbital flight in a Jupiter vehicle on May 29.24
This unusual angle of the Discoverer VII preparing for launch from Vandenberg Air Force Base, California, on November 7, 1959, reveals the white protective cover at the top of the rocket. This provided cooling to the payload on the launch pad and also shielded its identity from outside observers. This was the fourth launch of the C camera (KH-1). However, this satellite failed to reach orbit when its Agena upper stage malfunctioned. (Photo courtesy of the U.S. Air Force)
Because of the urgent need to get intelligence information (Bissell, Ritland, and everyone else privy to the program knew that the U-2’s days were numbered), the program directors chose to fly a camera at the earliest opportunity.
Thus, despite the elaborate cover story identifying Discoverer as having a biomedical payload, when the first camera became available before the life-support system could be made to work, no primate flights were ever conducted. The biomedical story did get publicity even if the more elaborate missions never flew, however, and helped to mask the true identity of the payloads.
Discoverer IV was launched on June 25, 1959. It was the first rocket to carry a reconnaissance payload, a C-model reciprocating panoramic camera; it was given the mission number 9001. The C camera was a direct descendant of the HYAC-1 camera developed for the WS-461L balloons. Unlike the HYAC camera, the film was located alongside the camera instead of above it. Designed by Itek and manufactured by Fairchild Camera and Instrument Company, it was an Tessar f/5 lens camera and had a focal length of 24 inches—twice that of the HYAC-1 camera.25 It swung through an arc of 70 degrees—less than that of the HYAC-1 camera—and exposed a swath of film 2.10 inches wide.26 It swung at a right angle to the direction of flight (the spacecraft faced rearward), so that at the center of its swing the camera faced straight down toward the earth.27 The C camera had constant velocity image motion compensation (IMC)—the compensation for the movement of the image as the satellite traveled at five miles per second. This meant that the satellite could only fly at one altitude or the images would appear blurred.
Contractors faced a number of unforeseen problems. Because the camera oscillated back and forth during operation, it imparted undesirable motions to the spacecraft. To counteract this, the designers installed a momentum balance wheel that oscillated in opposition to the lens/scan arm assembly. Fairchild engineers chose to use a set of gears and a ball pushing on a spiral screw shaft to produce the necessary motion, but this resulted in significant vibration.28 All problems were not of a technical nature either. Although Itek developed the lenses and Fairchild built the cameras, Itek did not have enough lens-grinding and -polishing machines or craftsmen to provide all the necessary lens elements. It had to subcontract this work to several precision optics firms.29
The C camera was designed to have 20–25-foot ground resolution, but at its best only achieved 35–40-foot ground resolution—which was still significantly better than what had been proposed for the earlier television-based and film-readout systems.30 Discoverer IV never reached orbit to test the camera, because of another Agena failure. But there was no time to waste. The program’s managers immediately began preparing for another launch.
“AUTUMN LEAVES”
Discoverer V, CORONA Mission 9002, also carried a camera but, unlike its immediate predecessor, did reach orbit on August 13. However, the temperature inside the vehicle was abnormally low and the camera failed on the first orbit. Telemetry on the ground indicated that no film ever made it into the return bucket, implying that it broke at some point during its path out of the film supply container. The reentry vehicle’s retro-rocket fired it upward instead of downward and it ended up in an orbit with an apogee of 1,058 miles. The launch of Discoverer VI, CORONA Mission 9003, quickly followed on August 19. Discoverer VI’s camera failed on its second orbit, probably also due to film breakage. The retro-rocket on its reentry vehicle apparently failed as well. Discoverer VII, CORONA Mission 9004, was launched on November 7; the Agena did not place it in orbit. Thirteen days later, Discoverer VIII, CORONA Mission 9005, was launched, but went into an eccentric orbit and once again no film went through the camera. Although the recovery vehicle ejected successfully, the capsule disappeared after separation and there was no way to know of its fate. CORONA managers had a Cold War to fight and could not take time to dwell on the failures.
At approximately the same time that the project engineers determined that the film in the satellites was breaking before going through the camera, ground tests in an atmospheric chamber yielded the same results. The acetate-based film degassed solvents in the vacuum of space and became brittle. It did not tear—it crumbled, like “autumn leaves,” in the words of one of the Itek engineers. Since the same kind of film had operated without problems on the WS-461L balloons at the near-vacuum of 80,000 feet, no problems were envisioned in orbit. But the hard vacuum of space was a significantly different environment than the upper atmosphere, and the CORONA camera’s film path, with its twists and turns (because of the need to accommodate the small diameter of the satellite), was much more complicated.
Eastman Kodak solved the problem. It obtained a license from DuPont to produce a polyester film base, which it coated with a high-resolution emulsion. This proved to be a very important technical feat. Polyester-based film was not unusual, but getting the high-resolution emulsion to bond to it required some creative chemistry on the part of Kodak.31 This film also weighed only half as much as the acetate-based film. Kodak’s high-resolution, lightweight films made aerial reconnaissance, and later space reconnaissance, possible.
WORKING UNDER CURSED STARS
There were other problems besides the film. Problems occurred in many different systems, but each one allowed engineers to learn something new about the system. At the same time, each failure also meant that the CORONA program was nowhere near operational. The “interim” program was rapidly depleting its initial supply of boosters and cameras. Bissell and Ritland concluded that CORONA needed greater quality control and more testing on the ground. They began a series of improvements to address the myriad problems.
The Agena had been developed for use on both the Thor and Atlas boosters. The latter was far more powerful and would be used for SAMOS (the renamed SENTRY) and the early warning MIDAS satellite. In order to conserve weight on CORONA, the Thor was allowed to burn until its fuel was exhausted instead of being shut down.32 This, coupled with the low altitude of the CORONA orbits, required extreme precision at orbital injection. An angular error of ±1.1 degrees or a velocity deficit of 100 feet per second would result in the vehicle failing to achieve orbit. Only a bigger booster, which was not yet available, could solve this dilemma. In the meantime, technicians cut weight from the vehicle by using tin snips and files to cut away surplus metal. This solution was crude, but it worked.33
Another problem centered on the spin and de-spin rockets used to stabilize the recovery vehicle during reentry. They were designed to fire to “spin up” the SRV before retro-rocket burn, and then to fire
again to stop the spin as the SRV reoriented itself according to aerodynamic forces. However, the propellant used in the tiny rockets was very unreliable. Project engineers had established an elaborate procedure for testing the rockets in batches, but defective rockets still made it through the testing phase and then failed in orbit. Fortunately, the solution was both elegant and simple—the two rockets were replaced by a cold-gas system that used a single nitrogen tank firing through two nozzles. This system went into operation with Discoverer XII, and the problem was solved.34
After the failure of Discoverer VIII in November 1959, a 2.5-month stand-down was ordered to correct the myriad problems. Once CORONA engineers felt confident that they understood the problem, launches resumed. On February 4, 1960, Discoverer IX, CORONA Mission 9006, was launched. This was the first mission to use the new polyester-based film, but it was never tested because the Agena did not achieve orbit. On February 19, Discoverer X, CORONA Mission 9007, was launched. This time the normally reliable Thor booster started to wobble soon after launch and the vehicle was destroyed. The payload was located by helicopter and retrieved by a crew who drove to the site by jeep.35
About this time discussions about canceling CORONA surfaced. Rumors circulated that the CIA simply was not capable of handling the job. Morale was at a low point. Air Force Colonel Paul Worthman, responsible for maintaining contacts between the CIA and the Air Force, reminded CORONA engineers that problems in such a pioneering and rushed program were inevitable. Bissell worked hard to squash the cancellation rumors. He urged everyone to push on.36
Brigadier General Osmond Ritland looking at the recovery package for the CORONA system. Note the small solid rocket motors around the circumference of the base cone of the reentry vehicle, used to spin it prior to retro-rocket burn. Reliability problems with the rocket motors led to their replacement with a cold-gas system. (Photo courtesy of the U.S. Air Force)
Discoverer XI, CORONA Mission 9008, was launched on April 15 and achieved orbit. This was the first mission to orbit carrying the new polyester-based film, and it was primarily because of the new film that the camera operated successfully. Unfortunately, the spin rockets apparently exploded during the reentry sequence and the capsule was not recovered.37 Yet another stand-down was ordered until the problems could be worked out on the ground. This led to the incorporation of the cold-gas spin system previously mentioned.
Another problem addressed during the stand-down was the extreme difficulty of determining exactly what had gone wrong in orbit. Once a satellite was launched, only a limited amount of telemetry existed to indicate the nature of the problem. For instance, when film was breaking, the engineers only knew that it was not reaching the collection bucket. They did not know if this problem was due to the camera or the film; the film’s disintegration in ground tests gave the necessary clue. Similarly, once the SRV separated from the Agena, there was no more telemetry. If the reentry vehicle did not come down to Earth, it could have been oriented in the wrong direction and fired up instead of down; or its small de-spin rockets could have exploded; or its engine could have not fired at all. All of these options had to be evaluated, taking extra time. The lack of good telemetry data was very frustrating to those attempting to make CORONA work.38 Program managers decided to fly Discoverer XII as a heavily instrumented diagnostic flight, without a camera, but with the new cold-gas spin and de-spin system. Unfortunately, Discoverer XII, launched on June 29, 1960, failed to reach orbit when its Agena upper stage malfunctioned. By this time, however, the success of the camera on the previous flight and faith in the reliability of the cold-gas system led virtually everyone involved to be optimistic about the chances for success on the next mission.39
In the meantime, the urgency of the program had also increased. On May 1, 1960, the Soviet Union, using an SA-2 missile, shot down Francis Gary Powers in his U-2 spy plane over Siberia. U-2 missions came to an abrupt halt and the best source of data on the strategic capabilities of the Soviet Union disappeared. The U-2 program had been far more successful and lasted longer than anyone associated with it expected. Nevertheless, its loss came as a distinct shock to many who had come to rely on it so heavily. CORONA was now the last, best hope to fill the gap.
FIRST LIGHT
The Discoverer XIII launch on August 10, 1960, was a repeat of the previous instrumented test flight. This time the vehicle performed as planned. But there was a glitch in the recovery effort, as the recovery airplane headed in the wrong direction. Fortunately, a Navy ship, the Haiti Victory, retrieved the capsule, which was returned to Washington, D.C., and presented to President Eisenhower during a White House ceremony. The only payload in the capsule was an American flag, which was given to Eisenhower.40 The ceremony and flag reinforced the fiction that Discoverer was solely a scientific and engineering program.41 After this success, CORONA managers were ecstatic. In East Palo Alto, Lockheed employees celebrated with a party at a local hotel. They threw the program manager, James Plummer, into the swimming pool and jumped in after him. (See photographs in chapter 9.)
Discoverer XIV, CORONA Mission 9009, launched on August 18, was the first totally successful mission. It returned photographs of the Mys Schmidta airfield in the Soviet Union and its capsule was successfully snatched out of the air by a C-119 flown by Captain Harold Mitchell. Earlier missions had carried 10 pounds of film, instead of the planned full 40-pound capacity. Mission 9008 had carried 16 pounds. But Mission 9009 carried 20 pounds, all of which was successfully exposed and transferred to the reentry vehicle.
Members of the 6594th Squadron transporting a film-return bucket (contained inside the drum) aboard a C-130 Hercules aircraft. The 6594th was the premier Discoverer recovery unit. The drum was transferred to any available Air Force aircraft at Hawaii headed for California and then transported to the Advanced Projects facility, where the film was removed for transfer to the East Coast. (Photo courtesy of A. Roy Burks)
The recovery sequence involving an air catch above the Pacific was the one aspect of CORONA that most Air Force officers—particularly pilots—found hardest to accept. It just was not possible, they felt. In actuality, the air catch proved to be one of the easiest aspects of CORONA to perfect. Pilots practiced by catching parachutes and buckets dropped from high-flying U-2 aircraft over the desert. The C-119 Flying Boxcar was soon replaced by the larger and more capable C-130 Hercules. The challenges of making complex machinery work in the harsh environment of space were immense, but soon the air catch of returning payloads operated like clockwork and pilots even perfected night recoveries of illuminated space capsules.
After retrieval, the film followed a complex route to the customer, photo-interpreters in Washington. Aboard the C-119 or C-130 the bucket was loaded into a light-tight bag inside a steel drum and transported to Hawaii. There the drum was transferred to whichever Air Force plane was available at the time and flown to Moffett Field or Travis Air Force Base in California.42 The drum was then taken to the Advanced Projects facility, where the bucket was removed. The film cassettes were flown to a processing center in the Northeast for development.43 The original negative was developed and copied and two duplicate positives were produced for use by the photo-interpreters. The duplicate positives were flown to Andrews Air Force Base near Washington, D.C., and were delivered to the Photographic Interpretation Center (later NPIC) for analysis.44
Before the first mission returned its film, photo-interpreters working on U-2 photographs from earlier missions over the Soviet Union were told to put away their U-2 materials and await the arrival of new photographic imagery, which they all knew was going to be from a satellite. Many of them found the initial results from CORONA disappointing. CORONA returned more imagery of the Soviet Union than the 24 previous U-2 missions combined and revealed 64 new Soviet airfields and 26 new surface-to-air missile (SAM) sites. The resolution of the imagery was good enough to spot airfields and to look at vast areas of previously uncovered territory, but it was not as good as high-resolution U-2 p
hotographs for hard intelligence gathering (such as counting actual bombers). After quickly exhausting the intelligence potential of the CORONA imagery, many of the photo-interpreters went back to their dated U-2 materials.45 About 50 percent of the ground targets on the CORONA imagery were obscured by clouds, but several important targets were photographed.46 The press release trumpeting the air catch of the SRV did not mention any of these facts, however.47
CHOOSING THE TARGETS AND EVALUATING THE IMAGES
In early 1959, Director of Central Intelligence Allen Dulles formed the Satellite Intelligence Requirements Committee (SIRC). The SIRC was to manage targeting for satellite programs independent of the Ad Hoc Requirements Committee (ARC), which established targets for the U-2 program. After the U-2 was shot down in May 1960, Dulles decided to replace both entities with a joint committee.48
On August 9, 1960, Dulles established the Committee on Overhead Reconnaissance (COMOR). COMOR was to
coordinate the adaptation of priority foreign-intelligence objectives and requirements established by USIB [United States Intelligence Board], members of USIB, or other committees of USIB, to the capabilities of existing and potential overhead reconnaissance systems; and shall examine and make recommendations, as appropriate, on such related matters as dissemination and any special security controls required, but shall not undertake to provide operational guidance.49
In short, COMOR was in charge of setting targeting priorities for intelligence collection by CORONA.