Atlantis Astronauts Arrive at NASA Spaceport for Launch Rehearsal

STS-115 commander Brent Jett introduces his crew to waiting media at Kennedy Space Center's (KSC) Shuttle Landing Facility after their arrival from Houston. The astronauts arrived at KSC on Aug. 7, 2006 for several days of flight training and a launch day dress rehearsal aboard the space shuttle Atlantis. CREDIT: NASA/George Shelton.

CAPE CANAVERAL - Destined to resume construction of the International Space Station, the Atlantis astronauts this week face a key pre-launch test - a practice countdown at Kennedy Space Center.

With about 150 to 200 engineers operating computer consoles in the NASA Launch Control Center, shuttle skipper Brent Jett and five crewmates will board Atlantis at pad 39B on Thursday for a launch-day dress rehearsal.

The exercise is one of the most important drills that any astronaut crew goes through during shuttle flight training. It's the only time astronauts don their partial pressure launch-and-entry suits and climb into their spaceship before the real deal on launch day.

"The training events for this week mark the last milestones for us in flight preparations," Jett said after the astronauts arrived Monday at KSC in sleek T-38 training jets.

"We're looking forward to a good week of training with the launch team, and a real smooth countdown, or at least a real smooth practice countdown," he said. "Once that's complete, we'll be real anxious to get back here at the end of the month and go into a real countdown and launch."

The Atlantis launch remains scheduled for Aug. 27 around 4:30 p.m. A three-day launch countdown is scheduled to begin on Aug. 24.

Shuttle preparations are proceeding on schedule. NASA contractors finished a flight readiness test of the shuttle's three liquid-fueled main engines during the weekend.

Under way this week are preparations to load toxic rocket propellant into the shuttle orbiter and solid rocket booster systems, including:

• Hydraulic power units that enable the shuttle's boosters to be steered in flight.

• The shuttle's orbital maneuvering engines and 44 nose-and-tail steering jets.

• Three Auxiliary Power Units that enable the ship's main engines to be swiveled in flight. The devices also provide power to control the orbiter's wing flaps, landing gear, nose wheel steering and brakes during atmospheric re-entry and landing.

The propellant loading begins this weekend and continues through Monday.

The Atlantis astronauts plan to fly the first space station assembly mission since the 2003 Columbia accident.

Their main job is to install a massive truss segment, expanding the metallic backbone of the station. The segment is outfitted with two giant solar panels that will significantly boost the amount of electricity that can be generated to run station systems.

Jett hopes the weather at the end of the month - a time when tropical storms and hurricanes typically form in the Atlantic - will be as good as the hot, relatively clear day that greeted them upon their arrival at KSC.

"We ought to save some of these days for the end of the month because I think we'll really need them," Jett said. "If we get a day like today on Aug. 27, we'll be in good shape."

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