Endeavour's crew, including Canadian, begin pre-launch drills

Seven astronauts,including Canadian Dave Williams and an Idahoteacher who has waited two decades to go into space, have beguntakeoff and landing drills to prepare for the Aug. 7 launch of thespace shuttle Endeavour.

Williams, a 53-year-old Saskatoon-born mission specialist, educator-turned-astronaut Barbara Morgan and their crewmates left their base in Houston and arrived in Florida on Monday for the final preparations for the 11- to 14-day mission to the International Space Station.

They'reto don their orange spacesuits and climb into the Endeavour for alaunch countdown drill at the Kennedy Space Center on Thursday.

Over the next few days,thecrew will be briefed on safety equipment, drive a tank used during an escape from the launch pad and make shuttle landing simulation runs.

Williams has been in space once before, spending 16 days on theshuttle Columbia in 1998.

He's expected to break a Canadian record by spending 19 hours floating outside the space station as he does assembly and repair work. The work will be spread out over three separate spacewalks.

Morgan was chosen as a backup candidate for the 1985 NASA teacher-in-space program. The woman chosen, New Hampshire teacher Christa McAuliffe, died with six others when the space shuttle Challenger exploded shortly after takeoff in 1986.

Morgan returned to teaching in Idaho, but said she wasn't deterred by the tragedy, and spent more than 20 years working to become a full-fledged astronaut.

She joined NASA's astronaut corps in 1998, and now, at 55, will operate Endeavour's robot arm on the 11- to 14-day assembly mission to the International Space Station.

To extend struts for solar power arrays

The astronauts are to deliver and install an extension for the central struts that support the station's solar power arrays.

During one spacewalk, the astronauts will replace a failed gyroscope, one of four electrically powered turbines that steer and steady the station.

The Canadian Space Agency and Saskatchewan's Ministry of Learning have arranged for students from four schools in La Ronge in northern Saskatchewan to ask Williams questions via a real-time video link as he orbits Earth.

Morgan will take part in as many as three live television question-and-answer sessions with students in Idaho, Virginia and Massachusetts.

The mission will be the first flight in almost five years for Endeavour, which underwent extensive refurbishment.