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CAPE CANAVERAL, Fla. - For the first time since the Columbia tragedy,
NASA's countdown clocks were ticking down the hours, minutes and seconds to launch, heightening the anticipation for a Wednesday liftoff of Discovery.
The countdown for the first space shuttle flight in 2 1/2 years began Sunday evening as Hurricane Dennis battered the Florida Panhandle off to the northwest. The mission's seven astronauts flew in from Houston on Saturday evening, a day early.
While Cape Canaveral was spared, Dennis still threatened to interfere with NASA's plans, with a week of thunderstorms on the horizon. Forecasters were hoping a ridge of high pressure would provide a break in the weather, however, and offered up fairly decent 70 percent odds for an on-time afternoon launch.
"It sure does feel good to be back in the saddle again. It's been too long," said payload manager Scott Higginbotham.
Test director Jeff Spaulding said excitement had been "building and growing" ever since the space agency overcame fuel-tank difficulties that prompted a launch delay a few months ago.
"It's only recently, I think, that it's all come to fruition where we can see the light at the end of the tunnel," Spaulding said.
"There's some excitement for people to get back to launching again and also, I think, maybe a quiet reserve as well, just remembering where we've been. But we all do feel confident that we've done it right."
Discovery will be making its first flight in four years when it takes off for the international space station with much-needed supplies and replacement parts.
Even before Columbia broke up during re-entry on Feb. 1, 2003, Discovery had been undergoing an extensive overhaul. The catastrophe prompted nearly 50 additional modifications, all of which will be demonstrated for the first time on this 12-day test flight. Techniques for inspecting the shuttle's thermal shield and fixing any holes also will be tested by the crew.
The biggest change, by far, is the redesigned external fuel tank.
Columbia's fuel tank lost a large chunk of foam insulation at liftoff. The debris slammed into the left wing, smashing a hole that proved catastrophic during re-entry. All seven astronauts were killed.
NASA removed the responsible section of foam and installed heaters in its place to prevent ice buildup from the super-chilled fuel. Just 1 1/2 months ago, engineers added a heater in another ice-prone spot on the tank; the work delayed the launch from May to July.
Managers also added extra checks for fuel-tank ice during the final portion of the countdown. Any significant patches of ice — which could be as lethal as flying foam — will mean a launch delay. Engineers considered putting infrared lamps at the pad to melt ice and covering vulnerable brackets with bags, but the ideas were scrapped, at least for now.
"With all the modifications, with all the improvements and changes and upgrades," Spaulding said, "certainly we can, without hesitation, say this will be the safest vehicle that we've ever had to launch."
That doesn't mean the tension level isn't high.
"It's a risky business so we're all sort of apprehensive," astronaut John Phillips said from the space station late last week. But he added, "I am fully confident that we've done what it takes to get this shuttle up here and I'm very anxious to see them come up here."
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Uprkos olujama,potvrdjen dan lansiranja
Nasa still hopes to launch space shuttle Discovery on Wednesday, despite the storms buffeting Florida as Hurricane Dennis hits the mainland US.
At a countdown status briefing, space agency officials re-stated their determination to fly Discovery on the first day of its July launch window.
There is said to be a 30% chance of bad weather stopping the launch on 13 July.
It will be the first shuttle launch since the Columbia disaster in 2003, which killed seven astronauts.
"Discovery is in excellent shape as we continue our preparations in anticipation of Wednesday's launch," Jeff Spaulding, Nasa test director told reporters here at the Kennedy Space Center (KSC) in Florida.
The US space agency (Nasa) officially set the launch countdown clock ticking on Sunday at 1800 EDT (2300 BST; 2200 GMT) for a scheduled launch at 1551 EDT (2051 BST; 1951 GMT) on Wednesday.
"Our main threat will be thunderstorms," said Kathy Winters, the shuttle weather officer. "With that we will have a 30% chance of KSC weather prohibiting launch."
DISCOVERY CREW - STS-114
STS-114 crew members (Nasa)
Commander Eileen Collins
Pilot James Kelly
Mission Specialist Andy Thomas
MS Charles Camarda
MS Wendy Lawrence
MS Soichi Noguchi
MS Steve Robinson
She added that if launch were to be delayed by 24 hours or 48 hours, the chances of cancelling launch due to high winds would rise to 40%.
Delaying Discovery's launch until after the weekend would do nothing to improve matters, Ms Winters explained, because hurricane centres expect other tropical storms to build over the next few days.
Discovery's seven-strong crew arrived at Cape Canaveral on Saturday evening - a day earlier than expected - because of Hurricane Dennis, which has blown in off the Gulf of Mexico.
Their time before launch on Wednesday will be spent carrying out simulations and, for Discovery's pilot James Kelly and Commander Eileen Collins, trying out difficult landing scenarios in a test aircraft.
Cold preparations
While the astronauts are busy with their preparations, engineers will load Discovery with the reactants to provide power while the vehicle is in orbit, conduct communications checkouts and retract the launch pad¿s rotating service structure to ready the vehicle for blast-off.
The shuttle's external tank will be cryogenically loaded with about 500,000 US gallons (two million litres) of propellants on Wednesday at 0600 EDT (11 00 BST; 1000 GMT).
"We're excited to be where we are now,' said Scott Higginbotham, Discovery's payload manager.
"It's taken almost three years for us to put this hardware together, take it apart, put it back together, take it apart."
The STS-114, Return to Flight Mission is due to last 12 days, with a landing set for 25 July at 1100 EDT (1600 BST; 1500 GMT) on the landing strip at the Kennedy Space Center.
It will carry spare parts and other equipment to the International Space Station.
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Postavljen satl
Nasa has said space shuttle Discovery is "buttoned up" and ready to fly as the launch countdown clock ticks.
Officials said they were "tracking no significant issues" as engineers made final preparations for lift-off from the Kennedy Space Center on Wednesday.
But they are watching the weather; a tropical depression to the south could turn into a hurricane in the next few days, meteorological experts say.
Discovery's mission is the first since Columbia broke apart in 2003.
We realise that the whole world will be looking at us on launch day
Stephanie Stilson, Nasa
This will be the most closely scrutinised shuttle launch ever. The shuttle will be tracked by cameras and radar to inspect for any debris that may damage the vehicle as it launches.
Unpredictable weather
"All of our hardware is onboard Discovery," said Scott Higginbotham, STS-114 payload manager. "We're buttoned up and ready to go."
But the unpredictable July weather could yet be an issue for launch.
Shuttle weather officer Kathy Winters told reporters that a weather system known as Tropical Depression 5 to the south could yet turn into a hurricane, to be known as Emily.
"We are not currently looking at any major issues that threaten the 13th. Obviously, weather is an unknown that we always have to deal with," vehicle manager Stephanie Stilson told the BBC News website.
"There are some paperwork-type issues that are still open. There is a slight chance - not very likely - that something will come out of the paperwork. But right now, we have very high confidence for the 13th."
Cameras are positioned on the ground, on planes, on the shuttle itself and on the International Space Station at different stages of flight to inspect for any possible damage.
According to US newspaper reports, also watching closely on 13 July will be a House and Senate delegation, as they consider Nasa's $16.6bn budget.
High expectations
Expectation weighs heavy on all involved in preparing the shuttle's return to flight.
"We realise that the whole world will be looking at us on launch day to make sure we're doing the right thing," said Stephanie Stilson. "It's important to Nasa, it's important to our government, it's important to our country and it's important to our international partners."
The window for launch will open at 1545 EDT (2045 BST; 1945 GMT) on Wednesday 13 July, and ground controllers will target the middle of this window - 1551 EDT (2051 BST; 1951 GMT) - for lift-off.
The mission is scheduled to last 12 days, with landing set for 1100 EDT (1600 BST; 1500 GMT) on 25 July at the Kennedy Space Center.
At 1530 EDT (2030 BST; 1930 GMT) on Monday, workers were to begin loading reactants into the shuttle's fuel-cell storage tanks, to provide the vehicle with power in orbit.
Loading of the shuttle's external fuel tank with cryogenic propellants to blast it beyond the atmosphere will begin at 0600 EDT (1100 BST; 1000 GMT) on Wednesday, approximately nine hours before launch.
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Odbrojavanje
CAPE CANAVERAL, Fla. -
NASA managers put a brief but embarrassing setback behind them as the countdown to the first space shuttle flight in 2 1/2 years entered its final hours Wednesday, with only predicted thunderstorms posing some concern.
A temporary window cover fell off the shuttle and damaged thermal tiles near the tail Tuesday afternoon, just two hours after NASA declared Discovery ready to return the nation to space for the first time since the Columbia disaster.
The mishap was an eerie reminder of the very thing that doomed Columbia — damage to the spaceship's fragile thermal shield.
Discovery and its crew of seven were set to blast off at 3:51 p.m. EDT on a flight to the international space station.
Fueling of the external tank, set to begin about an hour before sunrise, was delayed while workers changed a part on a launch-pad heater. NASA officials said the swapping out of the part wasn't expected to affect the launch time.
The lightweight plastic cover on one of Discovery's cockpit windows came loose while the spaceship was on the launch pad, falling more than 60 feet and striking a bulge in the fuselage, said Stephanie Stilson, the NASA manager in charge of Discovery's launch preparations.
No one knows why the cover — held in place with tape and weighing less than 2 pounds — fell off, she said. The covers are used prior to launch to protect the windows while the shuttle is on the launch pad, then removed before liftoff.
Two tiles on an aluminum panel were damaged, and the entire panel was replaced with a spare; Stilson called it a minor repair job.
Space agency managers held one last meeting Tuesday to address lingering technical concerns and later pronounced Discovery ready to fly.
"We have done everything that we know to do," NASA Administrator Michael Griffin said afterward.
The families of the seven astronauts killed during Columbia's catastrophic re-entry praised the accident investigators, a NASA oversight group and the space agency itself for defining and reducing the dangers.
Like those who lost loved ones in the Apollo 1 spacecraft fire and the Challenger launch explosion, the Columbia families said they grieve deeply "but know the exploration of space must go on."
"We hope we have learned and will continue to learn from each of these accidents so that we will be as safe as we can be in this high-risk endeavor," they said in a statement. "Godspeed, Discovery."
Discovery will be setting off on the 114th space shuttle flight in 24 years with a redesigned external fuel tank and nearly 50 other improvements made in the wake of the Columbia tragedy.
A chunk of foam insulation the size of a carry-on suitcase fell off Columbia's fuel tank at liftoff and slammed into a reinforced carbon panel on the shuttle's wing, creating a hole that brought the spacecraft crashing down in pieces during its return to Earth on Feb. 1, 2003.
During their 12-day flight, Discovery's astronauts will test various techniques for patching razbijacs and holes in the thermal shielding.
The crew members also will try out a new 50-foot boom designed to give them a three-dimensional laser view of the wings and nose cap and help them find any damage caused by liftoff debris. That is on top of all the pictures of the spacecraft that will be taken by more than 100 cameras positioned around the launching site and aboard two planes and the shuttle itself.
Until the window cover fell, NASA's only concern was the weather. Because of thunderstorms in the forecast, the chances of acceptable weather at launch time were put at 60 percent, down from 70 percent a day earlier.
"We're just hoping that the weather gods are kind," Griffin said. "Weather's always out there. We'll just deal with it as it comes."
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Odlozeno lansiranje
Space buffs from Tokyo to Indianapolis were disappointed and frustrated over the delay in launching space shuttle Discovery amid concerns over a faulty fuel-tank sensor.
The mission was put off at least until Saturday.
"Again?" Emi Tanaka, 26, said in dismay after trekking to a giant screen in downtown Tokyo with three other friends after a late night of work. The group had hopes of watching the liftoff around dawn, Tokyo time. A flight targeted for late May had earlier been set back by two months.
The launch had been set for live screening at the busy plaza in Tokyo's Shinjuku district and on local TV networks.
The inclusion of Japanese astronaut and local celebrity Soichi Noguchi in the shuttle crew of seven had boosted interest for this mission in Japan.
In the United States,
NASA had electronically linked with at least six museums to show the launch live on giant screens. The space agency invited teachers and schoolchildren — many of them from disadvantaged inner-city and rural schools — to the
Kennedy Space Center. For weeks, NASA has been promoting what the agency calls its "Return to Flight" outreach program.
"We're encouraging these students to pursue math and science careers," said NASA's chief education officer Adena Williams Loston. "They will be the Mars walkers."
Discovery's launch would mark the first shuttle flight since the Columbia tragedy 2 1/2 years ago, when the spacecraft disintegrated during its rapid descent toward Cape Canaveral, Fla., killing all seven astronauts aboard.
Even educators could not hide their apprehension.
"This now makes me a little nervous," said Deb Lawson, Spacequest Planetarium coordinator at the Children's Museum of Indianapolis. "Coming back from any kind of a tragedy and being able to accomplish something major is extraordinarily important."
After the scrub, space agency officials and VIPs tried, but failed to hide their disappointment.
"All I can say is shucks," deputy shuttle program manager Wayne Hale said as he sat among grim-faced NASA managers at a news conference.
U.S. Sen. Bill Nelson (news, bio, voting record), a Florida Democrat, flew on shuttle Columbia in 1986 and experienced four scrubs before launch. He said Discovery's crew was bound to be disappointed, but only briefly.
"Then you realize you don't want to be launched with a problem," Nelson said.
The space agency has until the end of July to launch Discovery, after which it will have to wait until September — a window dictated by both the position of the space station and NASA's desire to hold a daylight liftoff in order to photograph the shuttle during its climb to orbit.
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Problem sa gorivom na Discovery-iju odlozio lansiranje
CAPE CANAVERAL, Fla. - The astronauts had already climbed aboard the shuttle Discovery when
NASA halted the countdown with just 2 1/2 hours to go, scrubbing the first shuttle flight since the 2003 Columbia tragedy because of a fuel-gauge problem.
Shuttle managers had no idea whether Wednesday's trouble was in the gauge at the bottom of Discovery's fuel tank, a stretch of cabling and wiring, an electronics box inside the shuttle or something else entirely.
And they found themselves on the defensive, explaining why they pressed ahead with the launch when the same type of potentially fatal problem cropped up during a fueling test just three months ago and was accepted as an "unexplained anomaly."
Some engineers had pushed for further testing at the pad before committing to a liftoff, but were overruled by top managers who concluded that the replacement of cables, the electronics box and the tank itself was ample.
"We felt like we had a good system," deputy shuttle program manager Wayne Hale said at a grim-faced news conference Wednesday.
"We became comfortable as a group, as a management team, that this was an acceptable posture to go fly in," he said, "and we also knew that if something were to happen during a launch countdown, we would do this test and we would find it. And guess what? We did the test, we found something and we stopped. We took no risk. We're not flying with this."
Even if NASA had conducted another fueling test in June, Hale said it's unclear whether the fuel gauge would have malfunctioned the way it did in a checkout test: Instead of showing an empty tank, the gauge kept showing full.
The disappointment came just a day after an embarrassing turn for NASA, when a plastic cockpit window cover fell off the shuttle and damaged its fragile thermal tiles before the spacecraft had even taken off.
The launch was delayed until at least Saturday, and the postponement could last much longer, depending on the repairs needed.
NASA halted the countdown shortly after the seven astronauts climbed aboard for their journey to the international space station. Until then, the only threat to the mission was thunderstorms, which rained on the astronauts as they made their way to the launch pad.
From Cape Canaveral, where congressmen and astronaut families had come to witness the awe-inspiring sight of a rocket launch, to museums across the country where schoolchildren had gathered, the delay of the long-awaited return to space was disheartening.
"I wanted to see it really, really, really bad," groaned 8-year-old Michael Schamtin of Sherwood, Ore., who had waited for liftoff at the Oregon Museum of Science and Industry.
Shuttle managers said it was unclear whether Discovery could be fixed at the pad or would need to be returned to the hangar for more extensive repairs. They expected to have a better idea on Thursday — "but I wouldn't guarantee it," said Steve Poulos, a shuttle manager.
NASA has until the end of July to launch Discovery; otherwise it must wait until September. The launch windows are dictated by both the position of the space station and NASA's desire to hold a daylight liftoff in order to photograph the spacecraft during its climb to orbit.
When the shuttle finally takes off, the astronauts will test new techniques for inspecting and repairing razbijacs and holes similar to the damage that doomed Columbia in 2003.
Thousands of people had descended on the space center for the launch, including John Glenn, the first American to orbit the Earth, members of Congress, and family members of the seven fallen Columbia astronauts. Lawmakers and others refrained from second-guessing NASA's decision to press ahead before it had gotten to the bottom of the fuel gauge problem.
"I'm disappointed for all of us," said Sen. Bill Nelson (news, bio, voting record), D-Fla. But he added, "The system is working like it should."
Just a day earlier, the window cover caused damage to some of Discovery's thermal tiles — the very thing that NASA had worked so hard to avoid after Columbia's wing was pierced at liftoff by a chunk of foam insulation from the fuel tank. Discovery's tiles were quickly replaced.
In the 2 1/2 years since Columbia broke apart on its return to Earth, NASA has worked to fix its "safety culture," which the accident investigators concluded broke down during the flight. The space agency said it has had frank and vigorous discussions about the upcoming flight — including the fuel gauge problem — and encouraged engineers to speak up.
NASA also has concentrated on making the external fuel tank safer by reducing the risk that foam insulation, ice or other debris will break off at launch. The gauge that caused trouble on Wednesday is in the external fuel tank, but was unrelated to any of the safety modifications.
The space agency requires all four hydrogen-fuel gauges to be working to ensure that the main engines shut off at the precise moment in space. If the engines shut down too soon or too late because of an erroneous gauge reading, the results could be catastrophic. For instance, the engines could rupture if they kept running after the tank sprang a leak and ran out of fuel.
The space agency is looking closely at the possibility that flawed transistors in an electronic "black box" aboard Discovery might be to blame. The box used in the April test also had bad transistors, and when it was removed from the shuttle, the problem disappeared. Managers suspect a manufacturing defect with these transistors.
Shuttle program manager Bill Parsons stressed that the problem could be anywhere.
"This has to be looked at from end to end," he said. "We kind of need to keep our mind open."
http://news.yahoo.com/s/ap/20050714/ap_on_sc/space_shuttle;_ylt=A86.I0etR9ZCzEYBdySs0NUE;_ylu=X3oDMTA3MzV0MTdmBHNlYwM3NTM-]Ovde[/url]
[b]NASA proucava problem sa gorivom
CAPE CANAVERAL, Fla. - Hundreds of engineers are scrambling to figure out why a fuel gauge on the space shuttle Discovery failed right before its scheduled launch. Meanwhile,
NASA is clinging to the possibility that it might be able to make another attempt on Sunday.
Deputy shuttle program manager Wayne Hale said the fix would have to be fast and simple, though, to have Discovery ready by then. Most likely, NASA's first mission since the 2003 Columbia disaster will require more complicated repairs and be delayed into next week or even September, depending on the extent of work needed.
"Everybody is tremendously disappointed," said Michael Wetmore, director of space shuttle processing. "But everybody was also here 2 1/2 years ago and saw that we failed in our mission to protect the crew. So there's no one who wants to go forward with a potential risk to the crew that hasn't been appropriately analyzed and addressed."
NASA remains stumped as to why one of four hydrogen-fuel gauges in Discovery's external fuel tank malfunctioned during a routine pre-launch test Wednesday.
The seven astronauts were already on board, liftoff was little more than two hours away and the astronauts' families, members of Congress and space buffs around the world were eagerly waiting. The 12-day mission was loaded with interesting challenges that called for testing new safety and repair methods and delivering supplies to the international space station.
But everything came to a halt when launch controllers sent information mimicking an empty fuel tank. One of the fuel gauges remained stuck on "full."
Hours later, long after the tank was emptied, the troublesome gauge finally started working. That makes it an intermittent problem, Hale said, "which is the worst kind of thing to troubleshoot."
The problem could be in the gauge at the bottom of the tank — an electronic box aboard the shuttle that serves as a data-relay hub — or in the cables and wires in between.
The fuel gauges are critical and even though only two are needed, all four must be working properly for a launch to proceed. Hale said these low-level fuel gauges never failed until April, when two malfunctioned during a fueling test of Discovery's original tank. That tank was later replaced for other safety reasons.
If the fuel tank was empty but the sensors indicated full, the engine turbines would spin too fast and likely rupture — possibly damaging the tail of the spacecraft and dooming the crew. A ground test that accidentally caused that to happen back in the early 1980s resulted in severe "uncontained" damage, Hale said.
NASA is loath to repeat such a test on the shuttle's new and stronger turbopumps, Hale said.
On the other end of the scale, if the sensors were to trigger a premature shutdown of the main engines on the way to orbit, the shuttle would be forced to attempt a dangerous emergency landing in Europe or elsewhere.
"None of those options are really what you'd like to have happen to you," Hale said.
Workers will need to enter Discovery's engine compartment to get to the electronic box that is associated with the fuel gauges. The box contains transistors that may not have been assembled correctly.
NASA has a spare box ready to put in, but the device is exhibiting a signal interference problem and may not be reliable. If engineers have to put together a box from scratch, the work could take anywhere from 10 days to three weeks, Hale said.
It will be considerably more complicated if workers have to reach the fuel gauges themselves inside the tank.
NASA is up against the clock. If Discovery isn't flying by the end of July, the shuttle must remain grounded until September to ensure a daylight liftoff for good camera views — a requirement for spotting any damage during launch. That's one of the many changes called for by the Columbia accident investigators.
When Columbia blasted off on its doomed mission, NASA had no clear pictures of the foam insulation hitting the left wing and knocking a hole in it. The gash caused the spacecraft to break apart during re-entry on Feb. 1, 2003, killing all seven astronauts.
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Neznaju kada ce poleteti
NASA's first shuttle flight in more than two years has been put off indefinitely as the space agency mounts a massive investigation into why a fuel gauge failed right before Discovery's scheduled liftoff.
"We are going forward on a day-by-day basis," said deputy shuttle program manager Wayne Hale. "We have got the entire resources of the agency behind us to troubleshoot this problem."
Hale said that once the problem was identified and fixed, it would be another four days before the shuttle could launch.
"Everybody is going to want to ask, 'What is that date going to be?' Well, I don't know," he said.
It was the latest setback in NASA's grueling and drawn-out quest to return to space and recover from the 2003 Columbia tragedy. The space agency has made a multitude of safety improvements to the aging shuttle to avoid future catastrophes, efforts that have repeatedly delayed Discovery's mission.
Engineers are looking at whether any of those safety improvements — like additional heaters on the external fuel tank to prevent dangerous ice buildup — may be contributing to the failure of one of the four fuel gauges in the tank. When the gauge showed an improper setting, Wednesday's launch was canceled.
Hale said it's possible NASA could try to launch again late next week, "but that would require a very near-term lucky find" of the source of the problem.
Discovery's seven astronauts opted to remain in Cape Canaveral and wait it out, rather than return to their homes in Houston.
Managers had held out hope, however slim, that they might be able to launch Discovery within a few days. But with engineers no closer to figuring out why the fuel sensor malfunctioned Wednesday — a potentially deadly problem — NASA had no choice but to call for a lengthy standdown.
NASA is up against the clock. If extensive repairs are needed and the shuttle has to be moved off the launch pad and into the hangar, the flight could end up being bumped into September to ensure a daylight liftoff.
The space agency wants a clear view of the ascending shuttle in order to spot any launch damage. When combined with the constantly changing location of the international space station, Discovery's destination, this means that the shuttle must fly by the end of July or remain grounded until Sept. 9.
"We are not in any sense of the word becoming pessimistic about making the July launch window," Hale stressed to reporters. "We are here for the duration. We are committed to giving this the good, old college try until we get the problem resolved."
For the second full day, 12 teams of engineers around the country pored through data for clues as to why the hydrogen-fuel sensor failed during Wednesday's routine pre-launch test.
It was the same type of problem that marred a fueling test of Discovery in April. NASA replaced an electronic box and cables associated with the fuel gauge, as well as the fuel tank itself for other reasons, and chalked the failure up as an "unexplained anomaly."
This time, NASA is considering every angle, including the effects of a fully fueled spacecraft with all its systems running, said John Muratore, shuttle systems engineering manager.
Hale also suggested for the first time that if the problem can't be explained after days or weeks of effort, NASA might be forced to consider flying with the fuel gauge mystery unsolved.
The fuel gauges are needed to make sure a shuttle's main engines don't run too long or not long enough on the climb to orbit. Either case could prove deadly.
NASA's three surviving shuttles have been grounded ever since Columbia shattered in the sky over Texas on Feb. 1, 2003, killing all seven astronauts. A chunk of fuel-tank foam insulation came loose during liftoff and pierced the left wing, sending the spacecraft on a deadly descent two weeks later.
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