Florida Today(28-06-2006)
http://www.floridatoday.com/apps/pbcs.dll/article?AID=/20060628/NEWS02/606280371/1007/news02

Discovery countdown begins today

Crew practices landings, photographing release of external tank

BY TODD HALVORSON

CAPE CANAVERAL - A three-day countdown to the planned launch Saturday of shuttle Discovery is set to begin at Kennedy Space Center today while seven astronauts take part in final training for NASA's second post-Columbia test flight.

With the 18-story shuttle standing at launch pad 39B, mission commander Steve Lindsey and pilot Mark Kelly will practice landings five miles away at NASA's shuttle runway.

The dive-bombing training runs will be done in a Gulfstream 2 aircraft modified to mimic the shuttle's steep descent during final approach -- seven times that of a commercial airliner.

Mission specialists Mike Fossum, Stephanie Wilson and Piers Sellers will be at the pad, training to take pictures of the shuttle's redesigned external tank once it is jettisoned from the orbiter nine minutes into flight.

Scrambling to unbuckle from their seats, Fossum and Wilson will float up to overhead cockpit windows, rolling video and snapping still images as the 15-story fuel reservoir begins a destructive plunge back through the atmosphere.

The idea is to document the condition of the tank to help determine whether a potentially fatal foam-shedding problem finally is under control.

All seven crewmates -- including mission specialists Lisa Nowak and Thomas Reiter -- will check the fit of the pumpkin-orange partial pressure suits that they'll wear during launch and atmospheric re-entry.

Equipped with an emergency oxygen system, a parachute pack, life raft and other gear, the suits would enable the astronauts to survive a bailout into the Atlantic Ocean if a major shuttle system fails in flight.

The astronauts were more concerned about the weekend weather when they arrived Tuesday at KSC, disembarking from T-38 jet trainers just a few hours ahead of afternoon thunderstorms.

"I'm hoping the weather is going to improve a little bit in the next few days and we'll get off on time," said Sellers.

Liftoff is scheduled for 3:49 p.m. Saturday -- prime time for seasonal summer storms.

The first official launch forecast will be issued today. But extended forecasts from the U.S. Air Force's 45th Space Wing show a high probability of rain Saturday and Sunday.

Discovery's crew nonetheless is keyed up about the launch countdown, which will begin at 5 p.m. today.

"We're really excited to be here, ready to go do this for real," Lindsey said. "We've been training for a long time. We're as prepared as we're going to be."

A 102-foot-tall service structure will be pulled away from Discovery about 7 p.m. Friday, and launch engineers will begin pumping a half-million gallons of super-cold propellant into the shuttle's tank about 5:50 a.m. Saturday.

Lindsey said that launch preparations are on schedule: "The vehicle is ready and everything is looking 'go.' So weather permitting . . . we're going to be airborne on July 1."