RadioBanter - Space Shuttle Frequencies

Sat. Sep. 9 2006 12:01 PM ET
CTV.ca News

Space shuttle Atlantis finally blasted off this morning on a mission to the
International Space Station after weeks of frustrating delays from weather
and technical problems.

The six-astronaut crew, including Canadian Steve MacLean, lifted off at
11:15 a.m. ET from its seaside launch pad at the Kennedy Space Center in
Cape Canaveral, Fla.,

On the ground, NASA officials kept close watch on images from cameras zoomed
in on the shuttle. They were looking for any signs of hard foam breaking off
its external fuel tank -- the problem that doomed shuttle Columbia -- as it
streaked into space.

NASA declared the crew safe after a preliminary review showed no signs of
major foam loss before Atlantis separated from its external fuel tank.

NASA spokesman Kyle Herring said fuel cells that had forced launch delays
earlier this week were working as expected.

Officials gave the go-ahead early in the day to fuel up Atlantis and get it
ready for launch after there were no signs of problems from a fuel sensor
that had also been acting up.

The primary goal of the mission is to install a $372-million US solar power
module on the $100-billion space station.

Ahead of liftoff, flashing a broad grin and giving a double thumbs up,
MacLean, 51, boarded the shuttle as the clock counted down.

NASA engineers overnight drained and re-filled Atlantis' external fuel tanks
without the sensor exhibiting any problems.

This was the last chance in weeks for Atlantis to lift into space because a
Russian Soyuz capsule is slated for liftoff September 18 on a flight to the
ISS. If Saturday's window has passed, the launch would have had to wait
until October.

Atlantis is scheduled to deliver an addition to the ISS, for which
MacLean -- a laser physicist known to the crew as "the professor" -- will
play a significant role.
"He's going to do a couple of things that are rare and there will be at
least one first," said CTV's Tom Walters on Saturday morning, reporting from
Cape Canaveral, Fla.

"He'll be the second Canadian to walk in space; and he will be the first
Canadian to operate the Canadarm2 aboard the space station. That's going to
be a very significant part of this mission because the purpose of this
mission -- it's a construction flight -- is to take up a big truss and solar
panel assembly.
"That's going to expand the space station and give it a lot more
power-generating capacity. And Steve MacLean's role will be to manoeuvre
this assembly."
In fact, MacLean will have to manoeuvre it to within a three-inch tolerance
for the buckling clamps on the ISS to take hold of the school-bus sized
assembly.
"So a Canadian astronaut and Canadian technology playing an important role
in the expansion of the international space station," said Walters.
NASA wants the work finished before the Russian mission arrives at the
station at the end of this month.

The first day for the Atlantis crew will be dedicated to getting into orbit.
On the second and third days the shuttle will rendezvous and dock with the
ISS.
"But there are some steps to go through before they dock with the
international space station," said Walters.

"Since the Columbia disaster, there's a new protocol in place where one of
the things the shuttle has to do, and Shuttle Commander Brent Jett will fly
through this tricky manoeuvre called the RPM -- and that stands for
rendezvous pitch manoeuvre."

During the manoeuvre, the shuttle does a 360 degree back flip below the ISS,
and astronauts aboard the space station will photograph all of the heat
shielding to try to determine whether any damage was done during takeoff.

In the case of Columbia three years ago, it was damage to the heat shield
that left the spacecraft vulnerable upon landing and resulted in the shuttle
breaking apart while returning to Earth.

Thursday's launch was delayed by an electrical short in a fuel cell. ASA
managers decided Thursday night that it was operating within safe limits and
announced plans for a Friday morning launch. It's one of three aboard the
shuttle, which can operate with only two.
Former Canadian astronaut Marc Garneau, head of the Canadian Space Agency,
told CTV Newsnet that the sensors are "a complicated, technical piece of
equipment."

"These are sensors that are very critical. They tell you that you're out of
fuel, in this case it's liquid hydrogen," Garneau said. "The potential for
catastrophe is fairly high if you don't turn off the engine when you're out
of fuel."

The sensors are engine cutoff sensors, or ECO-sensors, that act as fuel
gauges and regulate the firing of the main engines during takeoff. If a
sensor shuts off too early, the shuttle doesn't make it into orbit. If it
shuts off too late and allows the tank to run dry, an engine could rupture.

The launch of Discovery was delayed by almost two months earlier this year
when one of the sensors was discovered to be faulty. All four were replaced
on Discovery at the time. A similar problem delayed a launch of the
Discovery in July 2005. The problem was never fully resolved.

MacLean and the other five members of the Atlantis crew had suited up to fly
Friday when it was scrubbed at the last minute.

Friday morning, the ground crew had pumped the last of 50,000 gallons of
liquid hydrogen and liquid oxygen into the shuttle tanks in preparation for
takeoff.
The shuttle is to deliver a 16,000-kilogram, $372 million addition to the
half-built space station during an 11-day mission. Four astronauts will take
three spacewalks to resume construction on the orbiting lab, the first work
in more than three years after Columbia broke apart while returning to
Earth.

This mission to deliver two girders crucial to the space stations' continued
expansion must be done before the final 14 shuttle flights.

The Russians plan to launch a Soyuz capsule on Sept. 18 ferrying two new
station crewmembers and the space station's first female tourist,
Dallas-area entrepreneur Anousheh Ansari.

Officials with both space agencies wanted to avoid the shuttle and Soyuz
meeting at the station, fearing a traffic jam.

Atlantis' mission will be the first since late 2002 to expand the space
station. The last two flights were tests evaluating a redesign of the
external fuel tank, whose falling foam was blamed for the Columbia accident.

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