Saturday, November 10, 2012
Idiots in dc destroyed our great capability!!
An ‘Operational’ Machine? Thirty Years Since STS-5 (Part 1)
By Ben Evans
STS-5 was the first ‘commercial’ Shuttle mission and featured the deployment of two telecommunications satellites – one for Satellite Business Systems and another for Telesat Canada – but the true nature of the reusable spacecraft as an operational vehicle remained inherently dangerous. Photo Credit: NASA
Thirty years ago, this week, the Space Shuttle completed one of the most remarkable metamorphoses in its history. After four test flights by the orbiter Columbia, which had wrung out many of its myriad capabilities, the reusable fleet of spacecraft was being declared fully operational for dedicated scientific and commercial missions. The official expectation was that Shuttle launch rates would increase to around two dozen per year, but behind the scenes were concerns aplenty. The Shuttle had already proven far more complex and tricky to process than originally thought and even NASA Administrator Jim Beggs and his deputy, Hans Mark, doubted that even a fleet of four vehicles could accomplish more than a dozen annual missions. As for the astronauts (many of them veteran test pilots), the mere notion that the Shuttle could be operational was ludicrous. On one occasion, Bryan O’Connor – later to become NASA’s safety chief – confided his worries in Ken Mattingly…and was told not to worry. “You and I both know,” said Mattingly, “that it will take a hundred flights before this thing’s operational.”
As circumstances would transpire, the Shuttle would fly ‘operational’ missions and fly them well; and yet – in the words of the Columbia Accident Investigation Board – would remain very much an ‘experimental’ vehicle until the very end of its career.
STS-5, the fifth flight of Columbia and the first operational mission, was intended to feature the deployment of a pair of commercial telecommunications satellites, SBS-3 for Satellite Business Systems and Anik-C3 for Telesat Canada, as well as the first Shuttle-based EVA by Mission Specialists Bill Lenoir and Joe Allen. The two satellites and their attached solid-rocket motors were each encased in a lightweight sunshade, protected by clamshell doors, and their carriage on STS-5 had netted NASA a first fee of $18 million. The agency hoped that the Shuttle would ultimately out-compete for commercial contracts with Europe’s new Ariane rocket, by also offering ‘free’ rides into orbit for customers’ representatives.
Early-morning fish-eye view of the STS-5 primary payload – the SBS-3 and Anik-C3 telecommunications satellites – arriving at Pad 39A for integration into Columbia’s payload bay. Photo Credit: NASA
For Bill Lenoir – who died in 2010 – his one and only journey into space was recalled with crystal clarity, even decades later. After being strapped into Columbia’s cabin, he curled himself as comfortably as possible…and fell asleep! He was awakened by Commander Vance Brand and hurriedly checked his straps and began working his checklists. Lenoir’s role during the STS-5 ascent was to serve as the ‘flight engineer’, seated behind and between Brand and Pilot Bob Overmyer, helping them with the systems. Seated downstairs on the middeck was Joe Allen, who would exchange places with Lenoir at the end of the flight and would serve as flight engineer during re-entry. This practice would be abandoned on subsequent missions and one Mission Specialist – the ‘MS2’ – would be specifically trained for all flight engineering duties.
Lenoir privately doubted that Columbia would possibly fly on her first attempt, owing to the vehicle’s complexity, but in spite of a failed computer synchronisation, the Shuttle thundered aloft at 7:19 am EST. Launch came right at the start of the 40-minute ‘window’, carefully timed to permit daylight conditions at the primary landing site of Edwards Air Force Base in California and to ensure that both the SBS-3 and Anik-C3 deployments were timed to obtain the proper Sun-angle when they prepared to make first use of their electricity-generating solar cells.
Five minutes before liftoff, Overmyer switched on the orbiter’s auxiliary power units and verified that they were running normally. Launch commentator Hugh Harris ticked off the final milestones, with a technobabble which only served to intensify the excitement: “T-1 minute and counting…the firing system for the sound suppression system on the pad is armed…T-55 seconds, the hydrogen igniters under the orbiter’s engines have been armed…T-40 seconds…we’re just seconds away from switching command of the countdown from the ground computers to the on-board computers…and we’ve had a Go for auto sequence start.” With 30 seconds to go, Columbia’s computers assumed primary command of all critical functions. “T-21 seconds and counting…the SRB nozzles are being moved to launch position…T-15 seconds…13, 12, 11, ten…we are Go for main engine ignition,” as a flurry of orange sparks from the hydrogen burn igniters gave way to a sudden, low-pitched rumble, “…six…we have main engine ignition,” as a sheet of translucent orange flame and billowing clouds of smoke swept the pad, “…three, two, one and…solid motor ignition…and liftoff…Liftoff of the first operational Space Shuttle mission, with two satellites on-board…and the Shuttle has cleared the tower!”
So dense were the ashen-grey clouds of smoke around Pad 39A that the STS-5 stack was almost obliterated for several seconds, but at length Columbia rose majestically from the murk, atop two dazzling orange plumes from her twin Solid Rocket Boosters. Brand could be heard announcing the onset of the “Roll Program” manoeuvre, as the vehicle performed an axial rotation to orient herself onto the proper flight azimuth for a 28.5-degree-inclined orbit, and Capcom Bob Stewart – seated in Mission Control in Houston – provided acknowledgement with a clipped “Roger Roll, Columbia!”
Columbia roars into orbit on 11 November 1982. Photo Credit: NASA
Climbing through the low atmosphere, the wind noise outside gradually intensified into something which could only be likened to screaming. It caused Overmyer some consternation. It was a rough ride; none of Columbia’s four earlier crews had mentioned such severe vibrations in their post-mission debriefings. At one point, Overmyer turned to Brand and remarked on it – “This is too rough, Vance. I’m afraid we’re going to come apart!” – but it was Lenoir, a civilian engineer, who settled the worries of the tough, crew-cutted Marine Corps aviator: “Relax, Bob. No use dying all tensed up!”
A minute into the flight, as Columbia approached an altitude of nine miles, she passed through a period of maximum aerodynamic turbulence, which required the computers to throttle the main engines back to just under two-thirds of their rated thrust. The passage through this period, nicknamed ‘Max Q’, was accompanied by an increase in the noise and vibration of the engines, although their performance remained within structural expectations. Shortly thereafter, the three engines were throttled back up to full power.
“Columbia, this is Houston, you’re Go at throttle up,” radioed Stewart.
“Roger, go at throttle up,” crackled Brand’s voice in response.
The sound from the boosters, meanwhile, remained sporadic and decreased to virtually nothing as the time approached, a little more than two minutes into the ascent, for their separation. As the boosters’ thrust tailed off, the crew felt as if they had stopped accelerating. When the separation motors fired and the boosters fell away, a bright, orange-yellow ‘flash’ appeared to stream up in front of the Shuttle’s nose and then sweep back above the front windows. Separation was accompanied by a harsh, grating sound, but both boosters performed nominally. At this point Columbia was more than 20 miles, above much of the sensible atmosphere and travelling at close to four times the speed of sound. With the boosters gone, the astronauts found it much easier to flip switches in the cockpit. It must have been a relief for Overmyer to see the back of the solids, for the rough ride calmed down considerably when they were gone. “Sure enough, it got all quiet and peaceful,” recalled Lenoir. “Riding on the main [engines]…was like an electric engine and you don’t feel it.” By eight minutes after launch, with three times the force of terrestrial gravity bearing down upon them, each man felt that he had someone heavy sitting on his chest. Breathing became difficult and talking was reduced to a series of guttural grunts.
Some eight minutes and 30 seconds since leaving Pad 39A, the main engines of Columbia were shut down as planned and the External Tank was jettisoned to follow a ballistic, suborbital re-entry and burn up over a sparsely inhabited stretch of the Indian Ocean. Brand and Overmyer pulsed the thrusters to push themselves away from the discarded tank; there was hardly a murmur of noise associated with the separation. They were in space…and the first traces of orbital flight were readily apparent, as washers, filings, screws, wire and other debris floated freely around the cabin…
For three of the four STS-5 crew members, the mission provided them with their first experience of spaceflight and their first view of the grandeur of Earth. For Bob Overmyer, it was an experience tinged with the disappointment of space sickness, but according to his crewmates he worked feverishly throughout the mission. Photo Credit: NASA
One thing that did not seem to be floating, though, was Lenoir himself. As Brand and Overmyer prepared to fire the Orbital Manoeuvring System (OMS) engines to circularise Columbia’s orbit, his first reaction was that they were not weightless. Peculiarly, he sat firmly in his seat, when his mind told him that he ought to be floating. Then he realised: he was strapped in so tightly that he felt that he still had G forces on his body; only when he lifted his checklist…and let it go…and it just hung there, comically…did the evidence of his eyes finally convince his brain of the nature of this new environment. The rise to orbit had been bone-shaking at times, but satisfactory overall, with no major problems.
From the astronauts’ perspective, the view of Earth from orbit, with its complete absence of lines and borders, the beautiful blue and white planet seemed totally at peace. “My overall recollection of the flight,” explained Allen, “is it was so extraordinary, and so short, and I was in kind of a mental saturation for the whole thing. I could hardly believe the beauty of it and the grandeur of it.” However, with only five days to complete two satellite deployments and a spacewalk, all four men briskly set to work. Immediately after Brand and Overmyer had completed the second OMS burn to circularise the orbit, Allen and Lenoir unstrapped and began to fold away their collapsible seats.
The OMS burns were truly a sight to behold…and to hear, too, for their rumble and vibration through the Shuttle’s airframe has been compared by more than one astronaut as something akin to a howitzer or a mortar blast. Allen and his camera were at the ready for at least one of these burns. “Since the burn was being done by Vance and Bob,” he explained, “Bill and I had only to just look out the back and see the engines ignite, and to my astonishment it looked like the back of the orbiter blew off…this enormous flash of light. You hear kind of a ‘whump’ of the engine starting, a flash of light, and then it’s gone, even though the engine continues to burn.” The phenomenon came about because the OMS engines are started ‘rich’, with more fuel than oxidiser, in order to produce a clean start to the burn. The flash lasted barely a fifth of a second, after which the fuel-oxidiser mix was rendered ‘lean’ again, “such that everything gets burned and there’s no light at all”. Allen would be impressed when his photographs were developed after the flight that one of them actually captured the instant of the OMS flash. “The exposure of a camera is a sixtieth of a second,” he said, “so you have to put a sixtieth of a second right during that fifth of a second, which is virtually impossible to do, but I got very lucky and was quite pleased by that result!”
Columbia’s Orbital Manoeuvring System (OMS) engines flare to life during one of the mission’s many ‘burns’. In the foreground, one of the two Pacman-like cradles used to house and protect the SBS-3 and Anik-C3 telecommunications satellites can clearly be seen. Photo Credit: NASA
The major success of their first day in orbit was the deployment of SBS-3, the first commercial satellite ever to depart the Shuttle. Six hours before the historic event, updated computations of Columbia’s orbit – including attitude, velocity and inclination – were radioed to Lenoir from the SBS control station in Washington, DC. Then, 40 minutes prior to deployment, Brand and Overmyer manoeuvred into the correct attitude with the payload bay facing into the direction of travel. Restraint arms pulled away from the satellite, then Lenoir flipped a switch to open the sunshade ‘jaws’ and impart a 50 rpm spin rate on the payload. This steady rotation helped to stabilise SBS-3 during its deployment. Next, at 3:20:18 pm EST, eight hours after launch and midway through their sixth orbit of Earth, he commanded explosive bolts to fire…and, seemingly in slow motion, the spinning satellite departed the bay at just 90 cm/sec, as Allen enthusiastically fired off pictures.
Immediately after leaving the vicinity of the Shuttle, command of the satellite passed to the SBS control station. Fifteen minutes later, Brand and Overmyer backed Columbia away to a distance of about 25 miles, aiming the orbiter’s belly at the payload in order to protect their delicate topside from the exhaust of the satellite’s attached Payload Assist Module (PAM)-D solid motor. At 4:05 pm, an on-board timer fired the upper stage’s perigee motor for about a hundred seconds to boost SBS-3 into a highly elliptical transfer orbit. Overall, the PAM-D’s performance was “satisfactory” and it separated from the satellite a few minutes after completing its burn. Shortly thereafter, SBS-3’s omni-directional antenna was raised and, over the next couple of days, it employed its own solid-propellant apogee motor to insert itself into the required near-geostationary orbit, then employed hydrazine thrusters to move into its final ‘slot’ at 94 degrees West longitude.
A little more than a day into their mission, Brand and Overmyer recircularised Columbia’s own orbit with a burst of the OMS engines. This set the stage for the deployment of Anik-C3 a few hours later, under Allen’s supervision. Launching the Canadian satellite followed much the same routine. During the afternoon of 12 November, the pilots performed two more OMS burns and would make another (the mission’s sixth overall) following the deployment to provide a safe separation distance prior to the PAM-D ignition. Repeating Lenoir’s procedure of the previous day, Allen opened the sunshade, spun-up the satellite and ejected it into space at 3:24:11 pm, during Columbia’s 22nd orbit, as she hurtled high above Hawaii. A perfect firing of the PAM-D, some 45 minutes later, duly inserted Anik-C3 into an elliptical transfer orbit. Like SBS-3, this orbit was a few hundred kilometres ‘higher’ than its planned ‘operational’ slot. The satellite then utilised its own motor to place itself into a near-geostationary orbit; by 16 November, it was on-station at 114.9 degrees West longitude, directly in line with Edmonton in Alberta.
Vance Brand (centre) holds a hand-prepared plaque to celebrate the crew’s success. Surrounding him are (clockwise from upper left) Bill Lenoir, Bob Overmyer and Joe Allen. Photo Credit: NASA
The astronauts celebrated by turning on music from the movie 2001: A Space Odyssey and unfurled a sign which would epitomise the growing maturity of the Shuttle as a kind of ‘space truck’. This sign has been reproduced countless times in books about the reusable orbiter and its achievements and it is surrounded in a famous photograph by the four astronauts of STS-5. Held by Brand, it read ‘Satellite Deployment by The Ace Moving Company. Fast and Courteous Service. We Deliver.’ Floating weightlessly around their skipper, head to head, were Overmyer, Allen and Lenoir. The idea for the sign, said Brand, actually came from Allen, “because we moved stuff to space”.
In those days, there was no system of Tracking and Data Relay Satellites to provide near-continuous voice and data coverage; in fact, the crew was only in communication with Mission Control in Houston for perhaps 15-20 percent of each orbit. Significantly, said Lenoir, the SBS-3 and Anik-C3 deployments were to occur whilst crossing the equator and “we never had communication with the ground” at this time. As a result, the astronaut supervising each satellite – Lenoir for SBS-3 and Allen for Anik-C3 – effectively became the satellite’s launch director, with the real final say over whether to deploy or not. Lenoir coined a new name for the two of them: ‘Orbital Launch Directors’.
Now, by the late afternoon of 12 November, Columbia’s crew could rest assured in the knowledge that the deployments were behind them. It was a triumphant moment for both the astronauts and NASA as an organisation. More than a decade of planning and development and billions of dollars having been poured into the programme, the Shuttle seemed to be finally proving its commercial worth. The next major objective for the STS-5 crew was to put the new Shuttle space suit through its paces…and on that front the four astronauts would encounter great difficulties and lasting disappointment.
Tomorrow’s article will focus on STS-5’s change of fortune: the Lost EVA.
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November 10th, 2012 | Tags: Anik-C3, Astronaut, Bill Lenoir, Bob Overmyer, Bryan O'Connor, Cape Canaveral, Columbia, EVA, Exploration, Explore, External Tank, Human Space Flight, Joe Allen, Ken Mattingly, Kennedy Space Center, KSC, NASA, rocket, Rockets, SBS-3, Shuttle, solid rocket boosters, Space, space exploration, space shuttle, STS-5, Vance Brand | Category: astronaut, Ben Evans, Columbia, Earth, Earth observation, Edwards Air Force Base, Exploration, Human Space Flight, Kennedy Space Center, KSC, Launch, NASA, satellite, Space, space shuttle
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