Storms Ground Fourth Endeavour Shot at ISS

The seemingly snake-bit Endeavour mission to the International Space Station missed its fourth consecutive liftoff opportunity July 12 as thunderstorms and lightning again shut down the launch. The volatile weather at Cape Canaveral also forced NASA to scratch a scheduled July 11 blastoff.

With storms within 20 miles of the shuttle landing facility, NASA stopped the countdown at T-9 minutes, and after polling the Kennedy launch team, mission control in Houston and the seven-person Endeavour crew, NASA called off the scheduled 7:13 p.m. EDT launch shortly after 7 p.m. NASA plans for another go at liftoff July 13 at 6:51 p.m.

"We got the vehicle ready, but the weather didn't cooperate," Launch Director Pete Nickolenko told Endeavour's seven astronauts. "We're going declare a scrub today and bring back the team tomorrow for another try."

The mission to deliver and install 4.5 tons of equipment to the ISS was scratched twice in June due to a mysterious launch pad hydrogen gas leak that appears to be resolved. After NASA completed a fueling test July 1, the space agency declared the problem fixed and there were no reported leaks during fueling for the canceled July 11 liftoff.

Endeavour is now scheduled to dock at the ISS July 14 with a cargo bay full of work that includes what Endeavour Commander Mark Polansky calls "really big pieces of equipment" that are needed to complete Japan's Kibo laboratory complex. The 16-day mission-the second longest in shuttle mission history-will require five spacewalks to unload and install a literal "front porch" for the ISS, allowing for space-exposed science experiments.

"It's a real exciting mission. We are the last mission that is taking up Japanese hardware on a space shuttle ... really big pieces of equipment that we're going to go ahead and leave behind on the space station for construction," Polansky said in a preflight interview.

Also inside Endeavour's cargo bay will be an integrated cargo carrier holding several pieces of spare equipment for the space station. Most of it-a spare space-to-ground antenna, a spare linear drive unit and a spare pump module-will be stored on an external storage platform on the station's truss. But six batteries for the station's oldest solar array will be installed.

Once the Endeavour reaches the ISS, things will be as busy inside the shuttle and space station as the spacewalkers, with all three of the available robotic arms being put to use, sometimes all on the same day. The shuttle's Canadarm and the station's Canadarm2 will be put through their regular paces for surveys, unloading cargo and moving equipment and spacewalkers around, and a new Japanese robotic arm will be making its debut to transfer science experiments.

"It's certainly really exciting for JAXA [Japan Aerospace Exploration Agency]," said Polansky. "For them, this is the last of their hardware that's going to be permanently attached to the space station. This completes their series."

The mission also marks another milestone for JAXA, with Japanese flight controllers on the ground operating their own berthing mechanisms for the first time. The Kibo external facility will never need to be connected to anything but a Japanese-built module, so the Japanese were free to use any berthing mechanism they wanted.

"Before, even when we had pieces of hardware that were built by someone else, we have, here in the U.S. control center, still maintained a lot of the technical leadership," said lead Station Flight Director Holly Ridings. "In this case, they truly have technical leadership for some of the things that must work to make the mission a success. It's unique."