Secret shuttle missions. Part 2

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

By Ben Evans
 


This is the second in a series of articles concerning NASA’s secret shuttle missions. This one in particular highlights an issue – that would later come back to haunt NASA. Photo Credit: NASA
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Before the loss of Challenger in January 1986, three main ‘markets’ were identified for the shuttle. Firstly, there was a commercial market, launching domestic and foreign payloads, followed by a NASA scientific market and finally a military market, dominated by the requirements of the Department of Defense. Former NASA Administrator Jim Beggs has proven unwavering in his insistence that removing commercial payloads from the Shuttle was a mistake – “The argument was that you shouldn’t risk lives,” he said, “but you’re risking lives anyway, when you fly the shuttle” – but in the wake of Challenger the space agency was left with its own scientific missions and a lengthy backlog of military satellites, optimised for the reusable orbiters.

The reader will recall from Part 1 of this series that the decision to partially declassify Mission 51J, yet retain the top-secret classification over most of the other military Shuttle flights, is significant, for many of those were probably reconnaissance or intelligence satellites of one sort or another. Many aspects of these ‘deep black’ flights remain veiled in mystery to this day. 

This is particularly true of the second post-Challenger flight, STS-27, which is almost universally accepted – though not officially acknowledged – to have carried the first in a series of radar-imaging and all-weather surveillance platforms, known by the code name of ‘Lacrosse’. (More recent satellites in this series have also been designated ‘Onyx’.) Over the years, a handful of images of these payloads under construction have entered the public consciousness and it has since become clear that Lacrosse was one of the largest and most expensive satellites ever to be deployed from the shuttle.     

Built by Lockheed Martin, Lacrosse was financed by the National Reconnaissance Office and the Central Intelligence Agency. Under the directorship of George H.W. Bush, in 1976 the CIA initiated efforts to develop a network of radar imaging and all-weather surveillance satellites. A prototype was tested in 1982 and Lacrosse was approved the following year. Design features included a large radar antenna and solar arrays to provide electrical power for its transmitter. Some reports have hinted that the arrays had a wing span of 50 m, leading to speculation that the power of the radar itself might have been in the region of 10-20 kilowatts, several times greater than previous orbital radars and possibly yielding a resolution of better than a metre. 

Orbiting at an altitude of 450 km, inclined 57 degrees to the equator, each Lacrosse cost around a billion dollars and rumor about its precise purpose has been rife for more than two decades. Some sources have suggested that B-2 Spirit bombers would have downlinked Lacrosse targeting data in real time to seek and destroy Soviet intercontinental ballistic missile launch silos. The website www.globalsecurity.org noted that, although later Lacrosses were launched aboard expendable Titan boosters, the unit placed into orbit by STS-27 was secured aboard Atlantis by means of standard trunnion attachments and the crew later received military citations – now declassified – which explicitly state that it was deployed using the Canadian-built mechanical arm.

The crew was formally announced in September 1987, with an anticipated launch date in the late summer or early autumn of the following year. Astronauts Guy Gardner, Mike Mullane and Jerry Ross had originally been assigned to the first military flight out of Vandenberg Air Force Base and were joined by Commander Robert ‘Hoot’ Gibson and a third mission specialist, Bill Shepherd. The latter is best known today as having commanded the first crew aboard the International Space Station, but his pre-NASA experience as an underwater demolition expert and Navy SEAL brought with it an interesting anecdote: that he had killed a man with his bare hands, whilst on a covert military operation. Totally inaccurate, Shepherd deadpanned: “The story was with knives!” His tall tale started making its rounds in Houston soon after his selection by NASA in May 1984. “I heard about it,” he said, “and I thought, this is just really too good to deny, so I just wouldn’t comment on it for a long time, which made people really wonder!” 

Hoot Gibson and his crew quickly earned their mission the moniker of ‘Swine Flight’ from the office secretaries and were even given novelty pigs’ snouts. (The nickname came about from Gibson’s penchant for making animal-like snorting sounds whenever attractive women were in the vicinity.) As with Mission 51J before it, STS-27 was totally classified and virtually nothing – not even the exact launch time – was revealed until 24 hours before liftoff. “All the software was classified,” Mullane related. “Everybody supporting it had to have clearances, but that was pretty transparent to us.” Jerry Ross had worked on classified shuttle payloads before his selection as an astronaut and he was aware of many of the protocols and procedures involved. “You have to work within secured facilities,” he said, “facilities that are swept, so that you don’t have any inadvertent electronic signals or voice going outside it, so it constrains you significantly on how and where you can do your business. When we travelled, we travelled on basically classified orders. I’d tell my wife I was leaving. I couldn’t, in most cases, tell her when I was coming home.” 

Not for five years after the flight would the astronauts be permitted to reveal even the slimmest of facts: that they had used the mechanical arm to deploy their payload. A launch attempt on 1 December 1988 was scrubbed, due to unacceptable cloud cover and strong winds at the Kennedy Space Center, but all seemed ready for a mid-morning liftoff on the 2nd. The countdown clock ticked down to T-31 seconds, just prior to Auto Sequence Start, and was held whilst the weather at the Transoceanic Abort Landing site in Morocco was monitored. Guy Gardner had already started Atlantis’ Auxiliary Power Units and a ‘Go’ or ‘No-Go’ decision had to be made quickly. At length, the good news came from the Launch Director: the TAL weather was acceptable and the countdown could resume. Within moments, the clock started ticking again. At ten seconds, the Go was given for the ignition of the main engines, which promptly roared to life. Launch came at 9:30 am EST and within nine minutes Atlantis was in orbit…though not safely. In fact, the events of the next few days would demonstrate once more how fine the line was between triumph and disaster. Not until after landing did Gibson’s crew realise how close they came to death on STS-27. 

The near-calamity which would engulf the mission could hardly have been further from anyone’s mind in the hours after launch, as Mullane uncradled the mechanical arm and grappled Lacrosse for deployment. “For once, the incredible beauty of the Earth passed unseen beneath me,” he wrote in his memoir, Riding Rockets. “I had eyes only for the payload, Atlantis and the robot arm…I steered the end of the arm over the payload grapple fixture and fired the snare, which rigidly latched the payload to the arm.” Downstairs, in the airlock, Bill Shepherd watched through a porthole to ensure that the clearances between the satellite and the bay were acceptable. At length, Mullane ‘flew’ Lacrosse on the arm to its release attitude and called to Gibson. Mission controllers gave them a Go for deployment and Lacrosse drifted away into the inky blackness. At this stage, one of the great unknown stories of STS-27 unfolds…the story of the ‘secret’ spacewalk. 


"No use dying all tensed up." As much as Mike Mullane (here pictured on Atlantis' flight deck) tried to accept his commander's words, both he and the rest of the STS-27 crew spent an uncomfortable final few days in orbit, preparing for re-entry. Photo Credit: NASA

Not surprisingly, Mullane made no reference to any such event, but more than a decade later, in February 2001, a pair of astronauts were outside the International Space Station. Tom Jones and Bob Curbeam had just completed their third spacewalk to install the US laboratory, Destiny, onto the steadily growing outpost. As well as being a significant mission, this was the hundredth American spacewalk and NASA had trumpeted this fact beforehand. Then, just as Jones and Curbeam were about to make a comment, they were told on a private communications loop to keep quiet. In his autobiography, Jones noted that “somebody had done a recount” and the actual hundredth spacewalk had been a couple of days earlier. “How could that happen?” asked Michael Cassutt in an August 2009 article for Air & Space magazine. “Had there been a secret spacewalk that never made it into the official tally?” The only hint of what might have happened came a few years later, when one of the STS-27 astronauts made an off-hand remark that they had experienced problems with Lacrosse after its deployment, which necessitated a rendezvous and some kind of ‘repair’. 

Of course, a rendezvous with a troublesome payload does not necessarily imply that a contingency spacewalk was needed to fix it – a balky antenna, for example, could have been easily unfurled with a nudge from the mechanical arm – but the question of whether a ‘secret’ excursion occurred on this secret mission, even more than two decades later, has never been answered…or even admitted. In 1993, a high-ranking intelligence official travelled from Washington, DC, to Houston to present National Intelligence Achievement Awards to astronauts who had participated in the secret shuttle missions. 

For the first time, they could wear the medals in public and Gibson was permitted to disclose that he had “returned” to the STS-27 payload. “We separated from it and it had a problem,” he later told an interviewer from the Smithsonian. “We re-rendezvoused with it and assisted with fixing it, separated again and left it.” Those handful of words are amongst the most tantalizing of the mission. In July 2009, Internet chatter on the website www.nasaspaceflight.com included speculation that Atlantis’ crew maneuvered close enough to Lacrosse to employ a low-gain antenna to command the activation of a failed high-gain dish. Still others remarked that communications during spacewalks are conducted on unsecured UHF frequencies and that, if one did occur, its progress should have been detectable on the ground. One observer remarked that ‘concealing’ a spacewalk would be hardly worth the effort, since it would have revealed nothing of substance about the payload. Until STS-27 is declassified, we will almost certainly never know the truth. 

Early on the second day of the mission, 3 December, the astronauts were awakened with disturbing news. A review of the launch video had clearly shown something – probably a piece of ablative insulator – breaking away from the nose of the right-hand Solid Rocket Booster about 85 seconds into the ascent…and striking Atlantis’ fragile thermal protection system. The crew had already seen a ‘white’ material on the forward windows. If the orbiter’s heat shield had been breached, it could spell disaster during their fiery descent through the atmosphere at the end of the mission. Gibson’s crew were instructed to use the cameras on the mechanical arm to carry out a visual inspection. Mike Mullane started the procedure by gingerly maneuvering the arm across the forward section of the payload bay and tilting its lower boom over the starboard side of Atlantis’ nose. All looked good: a pristine ‘checkerboard’ of undamaged black tiles. 

Delicately, Mullane moved the arm further along the fuselage, towards the shuttle’s belly, and the five men gaped in horror. White streaks were everywhere, clearly indicative of damage which had stripped off their outer black coating by a kinetic impact. “We could see that at least one tile had been completely blasted from the fuselage,” Mullane wrote. “The white streaking grew thicker and faded aft beyond the view of the camera. It appeared that hundreds of tiles had been damaged and the scars extended outboard toward the carbon composite panels on the leading edge of the wing.” The reader will recall that damage to one of these leading edge panels was ultimately responsible for the loss of Columbia in February 2003. Gibson’s crew knew that a single missing tile was probably survivable, but the leading edges of the wings were subjected to the most intense heat during re-entry. Damage to them could mean only one thing: that the fliers of STS-27 were dead men. Some observers have offered this as additional evidence that Ross and Shepherd did not perform a secret spacewalk, arguing that they might otherwise have been directed to perform a visual inspection of several areas of damage. 


NASA Administrator Jim Fletcher (second left, suited) inspects the horrifying damage to Atlantis after STS-27. This mission came so close to disaster - on only the second post-Challenger flight - that Hoot Gibson believed a different outcome would have marked the end of the shuttle programme. Photo Credit: NASA

The mechanical arm did not have the capacity to reach far enough to inspect the leading edges. Mullane called Mission Control. “Houston,” he said, with urgency clear in his voice, “we’re seeing a lot of damage. It looks as if one tile is completely missing.” He knew that flight controllers could see their downlinked video and was puzzled when the reply came back that the damage was not severe. Gibson keyed his mike. “Houston, Mike is right,” he emphasized. “We’re seeing a lot of damage.” Again, he was reassured that the damage did not represent a serious breach of the thermal protection system. The problem was made worse by the fact that the astronauts could not use their standard method of relaying imagery to the ground, due to the classified nature of the mission; they were forced to use a slow, encrypted transmission, which meant that the pictures received in Houston were of poor quality. 

Efforts to request higher resolution imagery from the flight were frustrated by the Department of Defense, which would not release it due to the level of classification. With only the encrypted images at their disposal, it seemed to flight controllers that the crew had been misled into seeing damage in what were actually poor lighting conditions and grainy images. Gibson was furious and convinced that Atlantis would not survive re-entry. To him, the pictures were crystal clear. He knew exactly what he was seeing. However, there was little that could be done. He told his crew to enjoy the rest of the mission. There was no point in dying all tensed up, he said. 

Early on 6 December, the final steps were taken to prepare Atlantis for her return to Earth. All five astronauts donned their bulky orange suits and Gibson executed the de-orbit burn to begin an hour-long hypersonic descent through the atmosphere, towards a landing site at Edwards Air Force Base, on the opposite side of the planet. Mullane ought to have been strapped into his seat on the middeck, but had asked Gibson for permission to linger on the flight deck, behind the flight engineer, Jerry Ross, and shoot video through the overhead windows. He would then get downstairs and into his seat as the G levels steadily increased. 

On autopilot, Atlantis descended across the sleeping Indian Ocean, over Australia and the expanse of the Pacific in barely 25 minutes. As they entered the ‘sensible’ atmosphere, compression against the orbiter’s belly steadily heated the air molecules into a white-hot glow. “I wondered what was happening underneath us,” Mullane wrote. “I had visions of molten aluminum being smeared backwards, like rain on a windshield. None of our instruments or computer displays showed Atlantis’ skin temperature. Only Houston had that data.” In time, the steadily increasing G forces obliged Mullane to take his seat. After an interminable period of waiting, punctuated only by the calm voice of Gibson, relaying altitude, velocity and G readings, Atlantis passed through the period of maximum atmospheric heating and wind noise could clearly be heard outside. Travelling at five times the speed of sound, Guy Gardner deployed a set of air data probes from the nose to provide airspeed and altitude data for guidance. Thirty kilometres above Earth, still travelling at four times the speed of sound, Gibson spotted the runway at Edwards. Travelling lower now, and passing below Mach 1, the cockpit buzzed noticeably and observers at Edwards were startled by the Ssuttle’s trademark twin sonic booms, which echoed across the desert. 

Throughout re-entry, Gibson had kept an eye on the gauge which showed the levels of deflection in the elevons at the rear of Atlantis’ wings. “If we started to burn through,” he told an interviewer, years later, “we would change the drag on that wing, which is exactly what happened to Columbia. We would start seeing ‘right elevon trim’, which means moving the left elevon down. I knew we would start developing a ‘split’ between the right and left wing elevon positions if we had excessive drag over on the right side. The automatic system would try to trim it out with the elevons. That is one of the things we always watched on re-entry, anyhow, because if you had half a degree of trim, something was wrong. You had a bunch of something going on if you had even half a degree. Normally, you wouldn’t see even a quarter of a degree of difference on that thing.” Before entry interface, Gibson had privately concluded that if he did see an elevon split of beyond a quarter of a degree, he had about 60 seconds of life remaining in which to tell Mission Control exactly what he thought of their heat shield ‘analysis’…

On this occasion, Atlantis was lucky, touching down on the dry lakebed runway at 3:36 p.m. PST, after a mission lasting four and a half days. Although NASA acknowledged the damage in its post-mission report, published in February 1989, the agency officially described re-entry as “normal in all respects”. Whilst this was, fortunately, the case, the experience of the crew and the condition of the vehicle were by no means normal. After wheel stop, the true horror of what the crew had endured – and survived – would become abundantly clear. “There was already a knot of engineers gathered at the right forward fuselage, shaking their heads in disbelief,” wrote Mullane. “The damage was much worse than any of us had expected.” 


This diagram details the damaged section of tiles on the underside of shuttle Atlantis' . Similar damage would lead to the destruction of space shuttle Columbia in 2003. Image Credit: NASA

No fewer than 707 tiles had been damaged, with one – in the area of the shuttle’s nose – missing completely. The latter had been located over a dense aluminum mounting plate for the L-band antenna, which may have prevented a burn-through at this point. All told, the damage extended from beyond Atlantis’ reinforced carbon-carbon nose cap, right along the belly and had stopped just short of the leading edges of the wings. The lower surfaces of the elevons were untouched, but the aft maneuvering pods sustained 14 impacts and the starboard rudder speed brake had also been hit repeatedly. The astronauts, engineers and NASA Administrator Jim Fletcher, who was in attendance, instinctively knew that Gibson’s crew had cheated death by a hair’s breadth. 

A Thermal Protection System Damage Review Team was immediately convened, chaired by John Thomas and Jay Honeycutt and featuring astronaut Don McMonagle on its panel, which reported in early 1989. They traced the cause to a change in the manufacturing process, intended to improve the performance of the ablative materials needed to protect the boosters from aerodynamic heating. For Gibson and his men, it brought back memories of the single, primary maxim of engineering: ‘Better’ is the enemy of ‘good enough’. If it worked, there was no need to fix it. Thomas’ team was present at the rollout review of the next Shuttle mission, STS-29, and scrutinized all Solid Rocket Booster manufacturing records to identify potential debris liberation sources. Years later, Hoot Gibson would remark that, had Atlantis been lost, the consequence would probably have been the end of the shuttle. “We had spent all that money and all that time, rebuilding and revamping, and we launched one successful mission and we lost the very next one,” he said. “I think the Congress would have said, okay, that’s the end, guys, we just don’t need to do this again.” 

As for STS-27’s classified payload, the Lacrosse, it would remain in orbit for more than eight years, finally reaching the end of its operational life in the spring of 1997. In his interview for the Smithsonian, Gibson related that his crew showed their classified movie in a debriefing to the Joint Chiefs of Staff at the Pentagon. The movie itself was top-secret and had to be carried around by a courier, in a locked briefcase, handcuffed to his wrist! 

To this day, Lacrosse’s precise purpose and achievements remain classified. Yet at one of their post-flight presentations in Houston, Gibson – demonstrating the dark humour of the fighter pilot – dropped one inaccurate clue. On 7 December, the day after Atlantis landed, a massive earthquake, reaching 6.9 on the Richter magnitude scale, had hit the Spitak region of Armenia, then part of the Soviet bloc. An aftershock, measuring 5.8, had followed within minutes. The entire city of Spitak was destroyed and at least 25,000 people were killed in the disaster, primarily due to poorly built apartments, combined with freezing winter temperatures, bad soil conditions and the nature of the notoriously earthquake-prone region, where the Arabian land mass met the Eurasian tectonic plate. Massive humanitarian aid was requested by Soviet General Secretary Mikhail Gorbachev. The United States, Belgium, Chile, China, France, Great Britain, Italy, Japan, Sweden, West Germany and others responded with rescue equipment, search teams and much-needed medical supplies. 

“I know many of you may have been very curious about our classified payload,” Gibson told the gathered astronauts at the Monday morning meeting. The entire room hushed in anticipation. “While I can’t go into its design features, I can say Armenia was its first target!” The military astronauts laughed, whilst the civilians cringed in disgust. As if to press the point further, with a twinkle in his eye, Gibson concluded: “And we only had the weapon set on stun!” 

The response from the female astronauts? “Don’t you guys ever grow up?”