Shuttle launch postponed to July

[Guest Glenn]

Source: Reuters

 

May 02, 2005

 

WASHINGTON: Space shuttle Discovery's launch will be delayed until July, NASA's chief said on Friday amid concerns the agency has not corrected the problem that caused the Columbia ship to break apart upon re-entry in 2003.

 

Michael Griffin, who took NASA's helm on April 14, said the decision was made after a pair of safety reviews in recent weeks. He mentioned the issue of falling debris, but said a range of issues dictated the delay from the current launch date of May 22 until a launch window between July 13 and 31.

 

"This is consistent with our overall approach to return to flight, which is that we're going to return to flight; we're not going to rush to flight," Griffin said at a news briefing. "And we want it to be right, so we're doing what we need to do to ensure that."

 

Falling debris during Columbia's launch hit the ship's wing, creating a breach that ultimately made the ship fall apart as it returned to Earth on February 1, 2003, killing all seven crew members.

 

The three-ship shuttle fleet has been grounded since then, slowing construction on the International Space Station and sidelining a repair for the Hubble Space Telescope.

 

William Readdy, a former shuttle astronaut who now heads space operations at NASA, said the safety reviews gave new data about the shuttle's heat-shielding tiles and the reinforced carbon-carbon material on the shuttles' wings.

 

It also showed ice falling from the external tank could be a hazard to the shuttle at launch, so NASA workers plan to install a heater in one section where ice may accumulate, Readdy said.

 

"We had enough work remaining to do that trying to go in May or early June just wasn't the smartest thing," Griffin said.

 

Discovery was moved to its Florida launch pad three weeks ago for a test of the tank, which was modified after the Columbia accident.

 

Shuttle manager Bill Parsons told reporters during a second briefing on Friday that the shuttle will be rolled off the launch pad and taken to the assembly building for additional work on the tank, following a period of time for trouble-shooting at the pad.

 

In addition to the heater, NASA is considering installing infrared spotlights at the base of the launch pad to warm the problem area. Another option is to wrap the affected area -- a bellows that allows an oxygen feed line to flex during launch -- with a special shrink-wrap plastic, Parsons said.

 

Engineers are concerned, however, that the plastic itself could be a source of debris, added deputy shuttle program manager Wayne Hale.

 

Griffin, who has said he would investigate whether to reinstate a shuttle repair mission for the Hubble telescope after the first shuttle returned to flight, said he now wanted work to begin on this mission before the shuttle launches.

 

NASA experts at the Goddard Space Flight Center outside Washington will be working on getting ready for a possible shuttle servicing flight to the 15-year-old telescope, Griffin said, invoking a gambling term to denote a certain risk.

 

"We're going to bet on the come a little bit, that we can do the servicing mission and get folks at Goddard started on doing what they need to do to enable that," he said.

 

Griffin added that none of the work geared toward the Hubble repair would be allowed to distract NASA from its first priority, a return to shuttle flight.

 

 

[Guest Glenn]

More news from AFP:

 

Tank test points to July lift-off

 

AFP

 

May 22, 2005

 

WASHINGTON: NASA tested controls in Discovery's external fuel tank for a second time Friday in preparation for the first shuttle launch since the fatal breakup of Columbia in 2003.

 

"Everything went without a hitch this time," said space shuttle program manager Bill Parsons. "Nothing we saw today should prevent a launch July 13."

 

A valve and a sensor that acts as a fuel gauge failed in tests on April 14, NASA said, in preparation for the mid-July blastoff, the first day in a launch window.

 

At the end of April, NASA delayed its mid-May scheduled launch by two months, to address a possibility that ice, formed from humid Florida air on the super-chilled tanks, would break free of the external fuel tank during launch and damage the thermal skin of the shuttle.

 

The earlier test however had not determined the origin of the equipment malfunction.

 

"At this point, the conclusion that you might come to is that we had some kind of connection that wasn't exactly right ... and therefore we've cleared this up," Parsons said.

 

NASA engineers remember all too well that it was a piece of insulating foam that broke loose at Columbia's launch, striking the shuttle and damaging its heat shield, ultimately provoking the tragedy.

 

Damage to the heat shield allowed superheated gasses to enter a wing of the space shuttle on February 1, 2003 as the vehicle re-entered the Earth's atmosphere, setting it alight and causing the Columbia to break up above the southwestern United States.

 

All seven astronauts on board were killed.

 

The Discovery's enormous tank was filled with nearly two million litres of liquid hydrogen and oxygen over an 11-hour period during a simulated countdown, spokesman for the Kennedy Space Center at Cape Canaveral Bruce Buckingham said.

 

On Monday, Discovery is scheduled to undergo hot-fire tests of auxiliary power units, according to the NASA statement.

 

 

[Guest Glenn]

Worries must be resolved before decision is made on July launch window

 

A propellant loading test with Space Shuttle Discovery on 20 May failed to satisfy concerns over two external tank components that were raised during the launch-pad tanking exercise in April. Worries remain about sensors in the liquid-hydrogen tank and these must be resolved before launch of the STS 114 return-to-flight mission.

 

The sensors command Shuttle main engine cut-off at fuel depletion. Also, a pressure-relief valve in the hydrogen tank opened and closed 13 times during the tanking test, as it did in April. This is considered the maximum number of times the valve can operate. Inspections are also planned to look for potential cracks in the landing gear after defects were found in the orbiter Atlantis.

 

A test of Discovery?s auxiliary power unit is planned before the Shuttle stack is rolled back into the Vehicle Assembly Building at Kennedy Space Center, where it will be fitted with a new set of solid rocket boosters and the modified external tank originally scheduled to fly on the second RTF mission, STS 121. After Discovery?s second roll-out in mid-June, there will be another tanking test before the decision on whether to stick to the 13-31 July launch window.

 

Meanwhile, NASA administrator Mike Griffin says there is no chance of delaying the Shuttle?s planned retirement in 2010, especially as work on the Crew Exploration Vehicle is being accelerated.