Thursday, February 9, 2012

Shuttle secret missions

Into the Black: NASA’s Secret Shuttle Missions – Part Three

By Ben Evans

Astonishing view of Atlantis' nocturnal launch on 28 February 1990, with the Vehicle Assembly Building and Launch Control Center in the foreground. Seconds after this photograph was taken, the Solid Rocket Boosters (SRBs) were jettisoned and Atlantis performed a unique 'dog-leg' maneuver to achieve a 62-degree orbit...the highest ever attained in the shuttle program. Photo Credit: NASA

 The Secret History of NASA’s Middle Child:Part 3: ‘Play Misty for Me’

Something strange happened in March 1990. Ground-based observers were busy tracking the orbital progress of a classified Department of Defense payload, recently deployed by Atlantis’ crew on STS-36, when they spotted something unexpected. The massive satellite, reportedly weighing around 17,000 kg, had proven extremely bright and an easy object to follow in the night sky, but on the 16th, barely two weeks after its deployment, the Soviet Novosti news agency reported that it appeared to have broken up into several large ‘pieces’. Had America’s latest national security sentinel malfunctioned and exploded, they gloatingly wondered? 

The Pentagon quickly rebutted such claims, insisting that “hardware elements…would decay over the next six weeks”. In total, five pieces of debris (designated ‘1990-019 C-G’) were monitored and speculation was rife over whether they represented a catastrophic loss of the satellite or were little more than jettisoned payload shrouds or instrument covers. One magazine published images of the STS-36 crew and cynically asked if they would have done better to stay at the breakfast table! Had the satellite – later identified as ‘Air Force Program-731’ (AFP-731) or ‘Misty’ – exploded or broken up…or was something else afoot? As with so much in the ‘deep black’ world of Department of Defense space operations, all was not what it seemed.  

The visual brightness of AFP-731 reached a magnitude of -1 under favorable conditions, similar to the very large KH-9 Hexagon and KH-11 Kennan imaging satellites and it is thought today that the STS-36 payload was probably around the same size, shape and weight as the Hubble Space Telescope. Indeed, the website www.globalsecurity.org noted that Misty weighed in the region of 16,640 kg at launch, with half a dozen propellant tanks and a short, offset telescope with a large, black-colored photo shutter window to permit wider fields of view. Electrical power came from a set of “curved, body-hugging solar arrays”, the website explained, consisting of “three segments…attached to a deploying boom mechanism that allows the panels to be rotated in one plane to track the Sun”. These arrays were composed of “battle-hardened” gallium arsenide. 

Misty had been deployed into space on 1 March, a day after Atlantis roared into the highest-inclination orbit ever achieved by the shuttle. Mike Mullane, one of the mission specialists, described this inclination – tilted 62 degrees to the equator, which offered the astronauts a broader view of Earth than any other crew in history and reached the Arctic and Antarctic Circles – as the only declassified component of their flight. Launching into this orbit had been a long time coming. When the crew was assigned in February 1989, they expected to fly in February of the following year. That much, at least, came true, but what the astronauts could not have anticipated was that they would endure no fewer than five postponements, before finally blasting off on their sixth attempt. 

Originally scheduled for 22 February, their launch was to occur in the early hours of the morning, which obliged them to adjust their sleep cycles accordingly in the Kennedy Space Center crew quarters. “We were going to bed at 11:00 am and waking at 7:00 pm,” Mullane wrote in his memoir, Riding Rockets. “Breakfast was at 8:00 pm, lunch at midnight and supper at 6:00 am. A vampire kept better hours!” The reason for the first 24-hour delay was Creighton himself; for several days, he had been bothered by a steadily worsening cough and, although he tried to avoid the flight surgeon, he could not conceal it for very long and was diagnosed with an upper respiratory infection. He had not improved by the 23rd or the 24th and the weather also took a turn for the worse, resulting in two more postponements. 


The official mission patch for STS-36. Image Credit: NASA

Creighton was moved out of the crew quarters, to avoid infecting the others, and placed in an old space suit room, painted brilliant white and illuminated by a full ceiling of fluorescent lights. His crewmates wished him a speedy recovery, but the opportunity for humor was not far away. “We placed his food tray on the floor,” wrote Mullane, “and used a long-handled push broom to shove it close to his table and then immediately retreated from the room.” Creighton croaked a laugh as they greeted him with plastic bags over their heads. Years later, he remembered that a combination of the awful sleep-shifting, sheer exhaustion and possibly catching a bug had most likely conspired against him. Despite the precautions, the others began to show the signs of sickness, too. First among them was Atlantis’ pilot, John Casper, who received medication. So too did mission specialist Dave Hilmers. The only astronauts left ‘healthy’ were Mullane and the third mission specialist, Pierre Thuot. 

With the launch of STS-36 now rescheduled for 25 February, it seemed highly unlikely, considering Creighton’s illness, that Atlantis would be able to go. As circumstances transpired, a malfunction was detected in a range safety backup computer at T-1 minute and 55 seconds. The clock continued counting down to 31 seconds and was held whilst engineers tackled the issue. During the hold, the prolonged liquid oxygen drainback resulted in the lower inlet temperature limits on Atlantis’ three main engines being exceeded, violating Launch Commit criteria. Unacceptable weather for a Return to Launch Site abort caused a fifth attempt on the 26th to be scrubbed and a 48-hour delay was enforced to give the ground crews some rest. 

Finally, on 28 February, the astronauts lay uncomfortably on their backs for several hours, waiting for a break in the weather. Rain showers lashed the Cape, whilst the Transoceanic Abort Landing sites in Spain were also coded as ‘No Go’. At length, fellow astronaut Mike Coats, flying the Shuttle Training Aircraft (STA) on weather reconnaissance, gave them the all-clear and confirmed with the pilots in Spain that the launch could go ahead. At 2:41 am EST, the countdown came out of an extended hold at T-9 minutes. John Casper brought up the Auxiliary Power Units shortly thereafter and at 2:48 am the crew were instructed to close their helmet visors. For Mullane, seated downstairs on the middeck for launch, the next few minutes were a blur. Ascent was unusual, since the normal maximum inclination was around 57 degrees. To achieve a 62-degree orbital tilt, Atlantis performed a ‘dog-leg’ exercise – flying downrange on a normal flight azimuth, then maneuvering to a higher azimuth whilst above the Atlantic – and, although this created a penalty in terms of performance, it was the only possible means of reaching the high-inclination orbit. 

“Normally, the highest inclination you’ll ever get is 57 degrees,” said Creighton, “which keeps you just off the East Coast, so in case anything bad happened, where you blew up, you’re not going to rain debris down on a major city in the United States. This particular flight was the one exception – the only time in US manned space flight – where we’ve ever gone beyond 57 degrees. It’s kind of hard to hide that fact after you launch, when you’re up there and the Russians are tracking you, so that was declassified after we launched.” (Prior to the loss of Challenger, the plan was for a mission requiring such a high inclination for its payload to launch from Vandenberg Air Force Base on a north-south trajectory.) For STS-36, that payload was deemed of such importance to the national security that ‘normal’ flight rules, which prohibited overflights of land, were suspended and Atlantis passed near Cape Hatteras, Cape Cod and parts of Canada during her climb to orbit.   

Having said that, their altitude was one of the shuttle’s lowest, often reaching only a little higher than 200 km. For Mullane, this presented stunning views of Earth, which made the Home Planet seem “hugely close”. The wind-rippled waves of the oceans were visible in astonishing clarity and, flying over the Caribbean, the humps and valleys of the sea floor stood out in stark relief. Elsewhere, supertankers in the Persian Gulf could be seen, with their V-shaped wakes glinting in the Sun, whilst further south, ribbons of plankton stretched many kilometers out to sea on the fringes of the Antarctic. On one occasion, Mullane saw a flotilla of icebergs in the Southern Ocean and used gyroscopically stabilized binoculars to take a look at the distant land mass of Antarctica. “The pole was nearly 1,800 miles distant,” he wrote, “so I had no view of it. Instead, I focused on the rugged coastal mountain chains. The occasional black of a windswept cliff was the only color in an otherwise sheet-white topography.” 


Commander John Creighton conducts photography through Atlantis' overhead flight deck windows. Five Department of Defense missions were flown by Atlantis between 1985 and 1991 and one must wonder if photographs from the 'deep black' missions wil ever enter the public domain. Photo Credit: NASA

Floating horizontally, he found that he could roll himself into a ball and plant his face against Atlantis’ forward flight deck windows, which, with the cockpit lights switched off, made it seem as if he were snorkeling in the Aegean Sea, watching the iridescence of sea life through a face mask. Over the Pacific, as trade winds of the northern and southern hemispheres met and mixed in the heat and humidity of the equator, ominous clouds flickered with electricity – “sputtering fluorescent light bulbs,” Mullane called them – as thunderstorms rippled across the region. He had already decided that STS-36 would be his final mission and was determined to spend this quiet time at the windows on his last full evening in space. Every hour and a half, Atlantis brushed the Arctic and Antarctic Circles and the astonishing diversity of Earth was displayed, map-like, beneath him: the dense Siberian taiga, the rolling dunes of the African deserts, punctuated in their north-eastern corner by the green of the Nile Delta, the snow-capped mountaintops of the Himalayas and the Andes…and, finally, the place he called home: the sprawling city of Albuquerque, New Mexico. Bordered by the Sandia Mountains to the east and with the mighty Rio Grande flowing through it, from north to south, this was the place to which Mullane and his wife, Donna, intended to return after this flight.   

More than two decades later, Atlantis’ flight remains secret, although it is known that AFP-731 was deployed on the second day in orbit. “The payload had been expected to be deployed at 27 hours into the mission,” wrote observer Ted Molczan, based in the Canadian capital, Toronto. However, observations made some 28-31 hours into the mission revealed only the orbiter and, somewhere between 34-35 hours, Atlantis’ orbit changed slightly, providing clear evidence of a separation maneuver from the payload. “Therefore, deployment probably occurred between 31.5 and 35.3 hours,” concluded Molczan. “It is possible that it occurred earlier and that the spacecraft were too close together to separate it with binoculars.” Certainly, the “separation burn” took place on the afternoon of 1 March and the payload was sighted, in an orbit of 248 x 260 km, some 57 seconds in time ‘behind’ Atlantis, on the morning of the 2nd. 

John Creighton and his crew returned to Earth on the 4th, touching down at Edwards Air Force Base at 10:08 am PST. Sketchy details trickled out in the following weeks: that AFP-731 was some sort of electro-optical reconnaissance platform, possibly with a signals intelligence component, and that it utilized a mechanism known as the Stabilized Payload Deployment System (SPDS), which ‘rolled’ it over the payload bay wall and released it in an offset, near-vertical angle of between 65-80 degrees. The SPDS, described in a 1989 paper by JSC engineers Guy King and Ted Tsai, was an electromechanical structure, capable of rotating the payload out of the bay at a pre-determined angular position and separating it on command. Mounted on the port side of the bay, it took the position normally occupied by the Canadian-built mechanical arm. 

“After the payload is stabilized,” wrote King and Tsai, “it is released through a double swivel toggle release mechanism, located within the release head.” By the time Atlantis landed, observers had already noticed that the satellite had increased its altitude from 254 km to 271 km and on 7 March it executed a much larger maneuver. After the sighting of the five mysterious objects in late March, nothing more was seen until mid-October 1990, when a team of European observers tracked something at an altitude of 811 km, inclined 65 degrees to the equator. Although the United Nations had received no notification of anything operating in that region, analysis of AFP-731’s track suggested that it was the closest possible contender and it was suggested that the ‘debris’ seen in March was actually associated with the transfer of the satellite to its operational orbit. Certainly, this orbit was adjusted again in early November – possibly to monitor the deteriorating situation in the Persian Gulf; Saddam Hussein having invaded Kuwait the previous August – although attempts to ‘find’ it in the weeks which followed were unsuccessful. It has also been suggested that another of AFP-731’s targets were the Soviet Union’s military assets in the Arctic, particularly the strategic archipelago of Novaya Zemlya. 

Over the years, the satellite’s ‘vanishing’ trick was assumed to represent an example of a new-generational spacecraft, capable of demonstrating optical or radar stealth to prevent adversaries from monitoring it or predicting exactly when it would overfly their territories. Not until 1996-97 was AFP-731 seen again by civilian observers, purely by chance, in binoculars, and more recent speculation has been aired that it possessed some form of inflatable ‘shield’, perhaps conical in shape and composed of very thin polymers, coated with highly reflective gold or aluminum. This shield, it is theorized, was designed to suppress the satellite’s optical or radar signature. Today, it is often known by the code name of ‘Misty’ and is thought to have been built by Lockheed Martin, specifically as a ‘low-observable’ spacecraft at a unit cost of around $360 million. Its original purpose, according to www.globalsecurity.org, was to permit the Reagan administration to catch the Soviets cheating on arms control agreements. Two more Misty satellites have since been inserted into orbit and it is generally agreed that the first-generation payload, deployed on STS-36, was probably de-orbited sometime after 1997. 


A beautiful image of Atlantis, sitting on the runway at Edwards Air Force Base at the end of STS-36. Photo Credit: NASA

Whilst the two military communications satellites deployed on Mission 51J were unveiled a little more than a decade after launch, it seems highly unlikely that any concrete facts will be revealed about intelligence platforms like Misty or Lacrosse for many years to come. John Creighton’s crew had all been subjected to intensive background checks by the intelligence community during the astronaut application process, but flying on a Department of Defense mission required a new level of security clearance. “There was additional background information,” he remembered, “because you were going to be cleared Top Secret for a clearance. Most of the military guys had already had a Top Secret clearance when they were in the military, but it’s only good for specific purposes. I’m sure they did a background check on us before we were announced as a crew, unbeknownst to any of us.” 

Creighton’s recollection is that only about two dozen other souls knew exactly what happened for the entirety of STS-36, including NASA Administrator Dick Truly and the mission’s flight directors. “Most of the people in Mission Control didn’t know specifically what we did,” he added. Yet for five military officers, the sense of pride at completing a mission for the national security interest was pervasive. “Even though I can’t talk about them,” Mike Mullane said, “I feel very, very proud about those DoD missions. I felt like that was something that had a significant impact on America’s security…and I was part of it.”          


The crew of STS-36 take a look at shuttle Atlantis on Launch Complex 39A at NASA's Kennedy Space Center in Florida. Be sure to check back tomorrow for the fourth installment in the "Into the Black" series. Photo Credit: NASA

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