CAPE CANAVERAL, Fla. — Discovery blasted off Tuesday morning to send seven astronauts into partly cloudy skies above Florida on the first space shuttle flight since the Columbia disaster 2 1/2 years ago.
The shuttle lifted off from the launch pad at Cape Canaveral promptly at 10:39 a.m. EDT to begin a 12-day supply and repair mission.
While in orbit, Discovery’s crew will inspect the most vulnerable areas of the spacecraft, using a new 50-foot, laser-tipped boom. They also will practice repairing samples of deliberately damaged thermal tile and panels.
During an early morning meal, crew members sported matching Hawaiian shirts. They smiled for a NASA television camera as astronaut Steve Robinson strummed a guitar. Later in the morning, they waved and gave a thumbs-ups as they walked to the van that took them to the launch pad.
Before boarding the shuttle, astronaut Soichi Noguchi held up an orange piece of paper made to look like an oversized card from the board game Monopoly that read “Get Out of Quarantine.” The astronauts have been isolated for much of July to keep them from getting sick. Astronaut Charles Camarda held up several signs for his family, including one that read, “Be Good for Mom.”
This was the second time the astronauts made the trip to Discovery for a planned liftoff. On July 13, the astronauts were loaded onto the shuttle before the day’s launch was srubbed because of a faulty sensor reading.
On Tuesday, the fuel sensors on Discovery’s giant external tank passed initial tests early. NASA officials monitored the sensors throughout the three-hour fueling process to make sure they functioned properly.
“All the sensors are performing as expected,” said NASA commentator Jessica Rye.
If the equipment trouble reappeared, NASA was prepared to bend its safety rules and press ahead with the launch anyway with just three of the four sensors working.
Only two sensors are needed to do the job. But ever since NASA’s return to space in 1988 after the Challenger explosion, the space agency has decreed that all four have to work.
NASA Administrator Michael Griffin called such a deviation from the rules “an acceptable risk.”
“Actually, it’s quite a low one,” Griffin told The Associated Press on Monday.
The fuel sensors are designed to prevent the main engines from running too long or not long enough, in case the fuel tank is leaking or some other major breakdown occurs. An engine shutdown at the wrong time could prove catastrophic, forcing the astronauts to attempt a risky emergency landing overseas, or leading to a ruptured engine.
After Discovery’s launch, NASA will take a look at changing the rule to require only three functioning sensors under certain circumstance, Griffin said.
Over the past few days, NASA rewired two of the sensors to try to diagnose the trouble and repaired faulty electrical grounding aboard Discovery in hopes that would solve it. But the space agency was unable to fully explain the faulty reading.
“We have addressed everything we know on the shuttle that can go wrong that we have the technology to fix,” Griffin said. “Some things simply are inherent to the design of the bird and cannot be made better without going and getting a new generation of spacecraft.”
But a retired agent in NASA’s inspector general office, Joseph Gutheinz, said the space agency does not appear to have learned its lesson with Columbia. Accident investigators criticized NASA’s tendency to downplay risks and discourage engineers from speaking up.
“It is clear to me that NASA continues to put mission over safety,” Gutheinz said. “I fear that if NASA is wrong this time, as they were for Apollo 1, Challenger and Columbia, manned space missions may be halted for a very long time in the United States.”
The launch promised to be not only an appraisal of changes in NASA’s safety culture, but also a test of the fuel tank that was redesigned after the Columbia disaster to minimize the chances of debris falling off.
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 Feb. 1, 2003. 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, since flying ice can be as lethal as foam debris. Engineers added a heater in another ice-prone spot on the tank, and a special crew planned to make extra checks for fuel-tank ice during the final portion of the countdown.
A few family members of the fallen Columbia astronauts planned to return for the second launch attempt. The VIP list was topped by first lady Laura Bush and Florida Gov. Jeb Bush, her brother-in-law.