After nearly a week of bad launch weather and technical problems, the U.S. space shuttle Endeavour has lifted off from Florida with a new crew for the international space station. shuttle astronauts are on their way to do more maintenance and assembly of the outpost.

Technicians have repaired a faulty shuttle engine valve regulating nitrogen gas and the weather has cleared sufficiently to let Endeavour take off on its 12 day mission.

Eight of those days will be at the space station, which gets a new U-S and Russian crew to replace the one in orbit since December.

The launch delay means that the station's current crew has broken the previous U.S. record of 188 days in space set by astronaut Shannon Lucid on the Russian space station Mir in 1996.

After they arrive at the outpost, shuttle astronauts will make three spacewalks for construction and maintenance. One of the repair tasks is to replace a faulty joint on the station's robot arm, which is required for future assembly missions.

The combined crews will also transfer tons of cargo and scientific experiments for the new station team to use.