CAPE CANAVERAL, Fla. -- Thwarted Monday by a balky hatch, a stuck nut, a dead battery and high winds, NASA crews battled ice on the launch pad through the night to prepare shuttle Challenger's schoolhouse flight for blastoff Tuesday.
Space agency officials aimed for a 9:38 a.m. EST launch of the mission that would make high school teacher Christa McAuliffe America's first private citizen in space and allow her to teach millions of schoolkids from her high-tech orbital classroom.
Officials gambled that an Arctic cold front barreling across central Florida would not disrupt liftoff plans despite temperatures expected to fall to a low of 23 degrees at the spaceport early Tuesday.
Launch crews began finding ice on upper sections of the launch tower, some 150 feet off the ground, by 10 p.m. Monday. They organized ice patrols, pumped anti-freeze through some fluid lines and let water spigots drip to keep the pad from freezing up.
'We are seeing ice in some areas, but not in critical areas,' space agency spokesman Jim Mizell said. 'The (launch) crew is on schedule over at the pad. They say it's a miracle because the winds are gusting very hard.'
A year ago a liftoff by Challenger was foiled by a freeze that iced launch pad equipment. This time, Mizell said, ice-fighting plans were ready for activation.
Launch crews drained Challenger's fuel tanks of half a million gallons of supercold liquid hydrogen and oxygen, recycled the countdown clock and began the nightlong process of counting down toward the Tuesday launch target.
They also devised ways to avoid the hatch problems that cropped up Monday and, compounded by a stripped nut on a hatch handle bolt and a dead battery in a drill needed to remove the nut, delayed the liftoff until after wind gusts had reached unacceptably high levels.
Forecasters said the weather should be fine Tuesday except for the extreme cold, with clear skies giving virtually unlimited visibility.
'We'll go tomorrow,' shuttle operations chief Robert Sieck predicted after Monday's cancellation. 'We think tomorrow is our best shot near-term. That's what we're going for.'
Should the freezing temperatures force another cancellation Tuesday, Sieck said, it would take until Thursday to recycle for another launch try. McAuliffe's flight on Challenger's has been delayed twice before by weather and three times by postponements in the flight of shuttle Columbia that preceded it. The latest delay put the mission six days behind schedule and created new problems for plans to fly a total 15 shuttle missions in 1986.
The launch cancellation Monday was particularly frustrating because a good launch opportunity was passed up Sunday based on predictions the day before that the weather would be bad. As it turned out, the cold front bringing the bad weather slowed down and conditions at launch time Sunday were fine.
After Monday's launch was called off, McAuliffe and her six crewmates emerged from Challenger's round hatch at 1:06 p.m. looking somber and haggard. They had been strapped in the shuttle's hard seats, lying on their backs with their legs in the air, for five and a half agonizing hours of uncertainty.
Shuttle commander Francis 'Dick' Scobee paused to inspect the hatch, which posed the key problem Monday. Then he, McAuliffe and crewmates Judith Resnik, Ellison Onizuka, Ronald McNair and Gregory Jarvis headed for crew quarters.
The string of problems Monday -- at times resembling a comedy of errors -- turned the attempted blastoff into a three-hour cliffhanger.
When the planned launch time arrived at 9:37 a.m., the weather was fine but the hatch was giving problems.
Technicians at first could not confirm it was closed firmly. Then a stripped nut on a 5-16 inch titanium bolt kept them from removing an exterior hatch handle. The battery died on the first drill brought in to grind out the bolt, and it took an hour to get a second drill and a hacksaw to finish the job.
By the time launch crews got the hatch fixed at 11:08 a.m., crosswinds were gusting to unacceptable levels at the spaceport's landing strip where Challenger would have to make an emergency landing in event of engine failure n liftoff.
Controllers gave up on an improvement in the weather at 12:36 p.m., half an hour before the launch 'window' ended.
The launch cancellation was a disappointment to thousands of spectators -- including McAuliffe's parents, her husband and two children, and scores of educators and teachers -- who braved chilly, gusty winds at spaceport viewing stands all morning to see the space teacher's ground-shuddering launch.
'I feel badly for everybody,' said McAuliffe's mother, Mrs. Grace Corrigan of Framingham, Mass. She said a planned family champagne celebration of the launch would give way to a dinner out 'that would make us all feel a little better.'
The flight will make McAuliffe, a 37-year-old social studies teacher from Concord, N.H., the first private citizen to fly in space. It will be the 10th launch for Challenger and the 25th flight in the shuttle program.
McAuliffe's presence on the crew has overshadowed the primary goals of the flight -- the launch of a $100 million shuttle communications satellite and the deployment of a boxy $3 million science station to study Halley's comet.
Plans called for McAuliffe to conduct two show-stopping lessons broadcast live to schoolrooms across the nation by the Public Broadcasting System on the fourth day of the mission.