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Sunday, March 1, 2015

Fwd: 25 Years Since Mission of STS-36



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Begin forwarded message:

From: "Gary Johnson" <gjohnson144@comcast.net>
Date: March 1, 2015 at 7:07:07 PM CST
To: "Gary Johnson" <gjohnson144@comcast.net>
Subject: FW: 25 Years Since Mission of STS-36

 

 

AmericaSpace

AmericaSpace

For a nation that explores
February 28th, 2015 

Now You See It: 25 Years Since the Mysterious Mission of STS-36 (Part 1)

By Ben Evans

The official crew patch for shuttle mission STS-36, which launched 25 years ago today, on 28 February 1990. Image Credit: NASA

The official crew patch for shuttle mission STS-36, which launched 25 years ago today, on 28 February 1990. Image Credit: NASA

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 the crew of Shuttle Atlantis on STS-36—Commander John "J.O." Creighton, Pilot John Casper, and Mission Specialists Mike Mullane, Dave Hilmers, and Pierre Thuot—when they spotted something they did not expect. The massive satellite had proven an extremely bright object to follow in the night sky, but on 16 March the Soviet Union's Novosti news agency reported that it appeared to have broken up into several large fragments. Thus began the strange and enigmatic story of Air Force Program (AFP)-731, the first satellite of the "Misty" series, and as with so much in the "deep black" world of Department of Defense space operations, all was not what it seemed.

Initially, the reaction of the Soviet Union—which was then a little over a year away from dissolution and already on the brink of ceding control over many of its satellite republics—was one of scorn, proclaiming that the United States' latest national security satellite had malfunctioned and disintegrated in orbit. 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.

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 (HST). Indeed, the website www.globalsecurity.org noted that Misty weighed in the region of 36,680 pounds (16,640 kg) at launch, equipped with a half-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.

The STS-36 stack rolls out of the Vehicle Assembly Building (VAB), bound for the pad. Photo Credit: NASA, via Joachim Becker/SpaceFacts.de

The STS-36 stack rolls out of the Vehicle Assembly Building (VAB), bound for the pad. Photo Credit: NASA, via Joachim Becker/SpaceFacts.de

Misty had been deployed into space on 1 March 1990, a day after Atlantis roared into the highest-inclination orbit ever achieved by the shuttle. Astronaut Mike Mullane described this inclination—which was tilted 62 degrees to the equator, thereby offering the STS-36 crew a broader view of Earth than any other crew in history and reached the Arctic and Antarctic Circles—as the only declassified element 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 1990, 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 (KSC) crew quarters. "We were going to bed at 11:00 a.m. and waking at 7:00 p.m.," Mullane wrote in his memoir, Riding Rockets. "Breakfast was at 8:00 p.m., lunch at midnight and supper at 6:00 a.m. 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 attention of the flight surgeon, he could not conceal it for very long and was diagnosed with an upper respiratory infection. His condition had not improved by the 23rd or the 24th, and the weather also took a turn for the worse, resulting in two more postponements.

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 John Casper, who received medication. So too did Dave Hilmers. The only STS-36 crew members left "healthy" were Mullane and Pierre Thuot.

Commander John "J.O." Creighton leads Pilot John Casper and Mission Specialists Mike Mullane, Dave Hilmers and Pierre Thuot out of the Operations & Checkout (O&C) Building on launch day. Photo Credit: NASA, via Joachim Becker/SpaceFacts.de

Commander John "J.O." Creighton leads Pilot John Casper and Mission Specialists Mike Mullane, Dave Hilmers, and Pierre Thuot out of the Operations & Checkout (O&C) Building on launch day. Photo Credit: NASA, via Joachim Becker/SpaceFacts.de

With the launch 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 (LCC). Unacceptable weather for a Return to Launch Site (RTLS) 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—25 years ago, today—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 (TAL) 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 a.m. EST, the countdown came out of an extended hold at T-9 minutes. John Casper brought up the Auxiliary Power Units (APUs) shortly thereafter, and at 2:48 a.m. the crew were instructed to close their 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 performance penalty, it was the only means of reaching the high-inclination orbit.

"Normally, the highest inclination you'll ever get is 57 degrees," said Creighton in his NASA oral history, "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 U.S. manned spaceflight—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, Calif., 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 violent climb to orbit.

 

Copyright © 2015 AmericaSpace - All Rights Reserved

 


 

AmericaSpace

AmericaSpace

For a nation that explores
March 1st, 2015

Now You Don't: 25 Years Since the Mysterious Mission of STS-36 (Part 2)

By Ben Evans

 

Atlantis rockets into the night on 28 February 1990, headed for the shuttle's first "dogleg" maneuver and the highest orbital inclination ever attained by a U.S. piloted spacecraft. Photo Credit: NASA, via Joachim Becker/SpaceFacts.de

Atlantis rockets into the night on 28 February 1990, headed for the shuttle's first "dogleg" maneuver and the highest orbital inclination ever attained by a U.S. piloted spacecraft. Photo Credit: NASA, via Joachim Becker/SpaceFacts.de

A quarter-century has now passed since one of the quietest missions in the shuttle's 30-year operational history. On 28 February 1990, the orbiter Atlantis and her STS-36 crew—Commander John "J.O." Creighton, Pilot John Casper, and Mission Specialists Mike Mullane, Dave Hilmers, and Pierre Thuot—rocketed into orbit for four days of activities on behalf of the Department of Defense. During that short period of time, the astronauts deployed a classified payload, known at the time as Air Force Program (AFP)-731, but more commonly known under the program name of "Misty," whose nature even today continues to mystify. As described in yesterday's AmericaSpace history article, Atlantis performed a "dogleg" maneuver during ascent to reach the highest inclination (62 degrees) ever achieved by a U.S. human space mission.

Having said that, Atlantis' altitude on STS-36 was one of the shuttle's lowest, often reaching only a little higher than 125 miles (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 Sea, 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 sunlight, whilst further south, ribbons of plankton stretched out to sea on the fringes of Antarctica. 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 (2,900 km) distant," he wrote in Riding Rockets, "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."

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 Ocean, 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 Himalaya and the Andes … and, finally, the place he called home: the sprawling city of Albuquerque, N.M. 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 intended to return.

Pictured in the flight deck simulator, the STS-36 crew consisted of (from left) John Casper, Pierre Thuot, Dave Hilmers, Mike Mullane and John "J.O." Creighton. Photo Credit: NASA, via Joachim Becker/SpaceFacts.de

Pictured in the flight deck simulator, the STS-36 crew consisted of (from left) John Casper, Pierre Thuot, Dave Hilmers, Mike Mullane, and John "J.O." Creighton. Photo Credit: NASA, via Joachim Becker/SpaceFacts.de

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 154 x 161 miles (248 x 260 km), some 57 seconds in time "behind" Atlantis, on the morning of the 2nd.

Creighton and his crew returned to Earth on 4 March 1990, touching down at Edwards Air Force Base, Calif., at 10:08 a.m. 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 shuttle's 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 Johnson Space Center (JSC) engineers Guy King and Ted Tsai, was an electromechanical structure, capable of rotating the payload longitudinally 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 Remote Manipulator System (RMS) mechanical arm.

"Two separable hinge-like devices connect at one longitudinal side or edge of the payload to respective ones of the payload trunnions at different longitudinally-spaced locations along the length of the payload," the NASA Patent Application for SPDS revealed. "Separation of the payload from the bay is made [by] unlatching a latch and by the use of a repulsion spring at the position of each hinge-like device. Two four-link mechanisms allow movement between payload and bay. Such accommodative movement is required, especially duting launch, when considerable vibration is encountered." One of the key aims of the SPDS was to more safely maneuver a payload away from the shuttle. "It is a feature of the present invention that the payload is safely outside of the bay before it is separated from the shuttle," the patent application continued. "This makes it possible … to prevent the payload from colliding with the shuttle. The separation … is thus less hazardous." Having said this, redundancy was provided in the form of a pyrotechnic separation system.

The official crew patch for shuttle mission STS-36, which launched 25 years ago today, on 28 February 1990. Image Credit: NASA

The official crew patch for shuttle mission STS-36, which launched 25 years ago today, on 28 February 1990. Image Credit: NASA

"After the payload is stabilized," wrote King and Tsai in their paper, "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 158 miles (254 km) to 168 miles (271 km), and on 7 March 1990 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 504 miles (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 Ocean, 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, at an inclination of 66.2 degrees and a lower altitude of about 457 miles (736 km), 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 GlobalSecurity.org, was to permit the United States to catch the Soviets cheating on arms control agreements. A second Misty satellite is believed to have been inserted into orbit in May 1999, and there has been some suspicion that the National Reconnaissance Office's NROL-15 mission—launched in June 2012—may have been a follow-on member of the same or similar class. However, it is generally assumed that STS-36's first-generation Misty was probably deorbited sometime after 1997.

After four days in space, Atlantis touches down at Edwards Air Force Base, Calif., on 4 March 1990. Photo Credit: NASA

After four days in space, Atlantis touches down at Edwards Air Force Base, Calif., on 4 March 1990. Photo Credit: NASA

Whilst the two Defense Satellite Communications System (DSCS) military communications satellites deployed by the shuttle on Mission 51J in October 1985 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 for many years to come. The STS-36 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," Creighton 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—Creighton and Thuot were both Navy, Casper and Mullane were Air Force, and Hilmers was a Marine—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."

 

Copyright © 2015 AmericaSpace - All Rights Reserved

 


 

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