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Planetary News: Human Spaceflight (2006)The Third Time is The Charm -- Discovery LaunchesBy A.J.S. RaylJuly 4, 2006
Despite controversy and a last minute fix of cracked foam on the shuttle's external tank, Discovery lifted off right on schedule at 2:38 p.m. Eastern Daylight Time (11:38 a.m. Pacific Daylight Time) from launch pad 39B at the Kennedy Space Center (KSC) in Florida, becoming the first shuttle to launch on the Fourth of July, Independence Day. Unlike the preceding three days of this long holiday weekend, it was hot and sunny on the coast of Florida today and the shuttle took off in blue skies. For the 7 astronauts on board, the firing of the solid rocket boosters and the blast-off has to be the best "fireworks" they've ever experienced on a Fourth of July holiday. Minutes before launch, commander Steven Lindsey seemed to confirm that when he said: "I couldn't think of a better place to be on this July 4th." Discovery is now on its way to the international space station (ISS) on a 12-day mission to deliver a new crewmember, Thomas Reiter, of the European Space Agency (ESA), as well as 5,000 pounds of supplies. The ISS Expedition 13 Commander Pavel Vinogradov and NASA Flight Engineer and Science Officer Jeff Williams watched the launch from the station and are preparing now to welcome the STS-121 crew. Discovery will also be delivering food, water, and other supplies, as well as a new oxygen-producing machine tucked in the payload bay inside the multi-purpose logistics module Leonardo, built by the Italian Space Agency. The mission is the 115th shuttle flight and the 18th U.S. flight to the ISS, which, when finished, will have cost the United States, according to projections, in excess of $30 billion. It will then cost on the order of $1.5 billion a year to operate. A considerable part of the increased costs in recent years comes from the fact that the space shuttle is the only spacecraft that can get the large parts up to the station to finish it, and the shuttle hasn't been flying much lately. Today's launch -- which is only the second since the Columbia tragedy -- follows weeks of controversy about the potential of foam flying off the external tank and possibly causing damage to the orbiter. Space Shuttle Columbia disintegrated on reentry on February 1, 2003, because foam that had taken in water that turned to ice broke off and hit the leading edge of one of that shuttle's wings. On reentry, the heat seeped in between the tiles and the tiles began "zipping" off. There was no hope at that point of bringing the crew home alive. All 7 astronauts on board and the orbiter were lost. The mission management team gave today's countdown the green light last night following analysis of yet another discovery of cracked insulation foam. The cracked foam was found on an upper section of the external tank, near a bracket that holds the liquid oxygen feedline in place, during a routine inspection Sunday night after the draining of the external fuel tank, which must be done if the stand-down is any longer than 24 hours. The approximately 3-inch-long, triangular foam chunk broke away from a bracket holding a liquid-oxygen fuel line in place. Engineers think that maybe it was "pinched" off as the 0.1-inch-thick aluminum tank contracted and expanded during filling and emptying. The engineers also said they believed that the piece of foam, had it come off during launch, would not have seriously damaged the shuttle. It would have missed the fragile leading edges of the wing, they said, and instead hit the thermal tile on the underside of the craft. According to the official NASA statement, "[e]xtensive inspection showed that the area around the crack is intact and there is no concern for overheating around the bracket, as there is adequate foam still in place around the strut. Additional borescope inspection of the tank revealed that the metal bracket itself has no cracks." The flight team is no doubt currently reviewing the videotapes of the launch now checking for any signs of flying foam.
In the three and a half years since Columbia disintegrated on reentry, NASA spent $40+ million on the investigation that determined the loss was caused by foam from the fuel tank breaking off and hitting the leading edge of the left wing during lift-off, exactly as some engineers had anticipated and feared, and tens of millions more working the problem. A large part of the fix came with crews removing some 35 pounds of insulating foam in two large chunks along the side of the tank that engineers decided would not endanger the launch of the shuttle. Yet, foam remains the shuttle's greatest enemy right now and there is no way to completely stop it from flying off. Losing foam does not immediately signal failure and, actually, is expected, according to the official NASA documents. The size of the foam and location of the loss is what counts, the officials say. The goal is to make sure only tiny "harmless" pieces known as "popcorn" break off during launch. This latest incident comes on the heels of the controversial decision last month to launch Discovery even though the top safety officer and chief engineer voted "no go" because of the foam issue, and about a year after Discovery launched the Return to Flight following the Columbia disaster and was hit by a 1-pound chunk of foam that peeled away during launch. That chunk narrowly missed the right wing, and led to the grounding of the remaining 3 spacecraft in the fleet again. Although the source of last year's foam was removed, many engineers have urged NASA Administrator Michael Griffin to see that they remove even more tank insulation before attempting another mission, specifically from the ice frost ramp that covers a number of brackets and lines down the side of the fuel tank. Griffin, however, said that he wants to leave them in place to see how the shuttle performs during this mission. But at a June 16-17 flight readiness review, Bryan O'Connor, chief safety and mission assurance officer, and Chris Scolese, chief engineer, voted "no-go" for launch. At the end of the 2-day review, the other 23 shuttle management team members gave the green light for launch, outvoting the two dissenters. The majority contended that even if foam flew, it would not endanger the 7 astronauts inside. Although O'Connor and Scolese went on record as recommending a delay, they did not oppose the launch, because the space station would serve as a safe haven for the Discovery crew if their ship were damaged. "We do not believe we are risking the crew," Griffin said at a press conference following the go-for-launch decision. Since then, the NASA Administrator has vigorously defended his decision to launch the shuttle over the dissenting objections, saying that engineers have lowered the risk of damage to the spacecraft from falling fuel tank foam as much as they can. Meanwhile, the space agency remains deeply troubled. The dilemma that NASA confronts is that the space shuttle must be retired, as it stands now, in 2010 -- with a growing number of vocal observers and insiders lobbying to retire it now. But the agency has a commitment to its international partners to finish the construction of the half-built ISS. To accomplish that goal, NASA will have to successfully launch 16 missions in the next 4 years, or about 4 launches every year beginning next year, a highly ambitious and aggressive agenda, and probably not realistic by most veterans, even if there was no foam problem. In addition, NASA must build a replacement for the shuttle system -- the so-called Apollo-on-steroids CEV program is now underway -- and it is attempting to do so at a cost to science, research and exploration that many in the space community believe could deleteriously impact the future of this civilization. Drastic cutbacks have been instituted across the board and NASA's focus has become "dangerously myopic," according to Louis Friedman, executive director of The Planetary Society. At the same time, the dissention among the ranks at JSC is real and ongoing. While N. Wayne Hale Jr., manager of the Space Shuttle Program, who was promoted from deputy chief of the Flight Director Office for Shuttle Operations after the Columbia disaster, commented in past weeks that the dissenting opinions on this launch indicated "every voice is heard" and that "the agency has really changed," there is a growing number of others who disagree.
The director of engineering at Johnson Space Center (JSC) Charles Camarda, a former shuttle astronaut and veteran aerospace engineer, said in an e-mail to colleagues and reporters last week, that he was taken off duty for the launch of Discovery, on which he flew last year, and was reassigned as a result of his objections to fly the spacecraft without additional work and review. Another engineer at JSC, who requested anonymity for fear of his job, said: "Nothing has changed here. Nothing. NASA continues to fo a lot of insane things and not always because we don't know they're stupid, but because they are political decisions," he said. Consider the foam issue and where the tanks are built, at the Michoud Assembly Facility, in New Orleans, he said. Essentially, the tanks are built and the foam is then sprayed on at this facility (which is not a clean room) and the tanks are then stored there outdoors. "Now, if you really wanted to make sure something was going to stick, shouldn't you choose a dry environment, like Arizona, instead of Louisiana where the ambient humidity alone ensures nothing ever really dries?" [Hurricane Katrina damaged the Michoud facility and NASA's Stennis Space Center in Bay St. Louis, Mississippi, where shuttle engines are tested. NASA estimated repair and recovery costs to those facilities of about $1.1 billion last year.] Despite the disagreements, Discovery is spacebound, all systems seem to be operating well, and its 12-day mission has begun. On STS-121, Steven Lindsey commands the crew of 5 American astronauts, pilot Mark Kelly and mission specialists Michael Fossum, Lisa Nowak, Stephanie Wilson, and Piers Sellers, and Thomas Reiter, who will be staying on with the Expedition 13 crew on the ISS. While docked, the STS-121 crew is tasked with testing new equipment and procedures to improve shuttle safety, as well as deliver supplies and make repairs to the station. Named for two famous sailing ships commanded by Henry Hudson and James Cook, Discovery first flew in 1984. |
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