WASHINGTON — NASA’s final space shuttle flight is targeted to launch July 8 at about 11:40 a.m. EDT from the agency’s Kennedy Space Center in Florida. Four veteran astronauts will fly aboard shuttle Atlantis to deliver supplies and spare parts to the International Space Station.

This date was targeted based on NASA’s current planning. An official launch date will be announced following the June 28 Flight Readiness Review.

There are several non-standard activities, including a tanking test followed by an X-ray inspection of a section of the external fuel tank, which may affect Atlantis’ processing. The tank consists of three sections. Mission managers want to X-ray aluminum support beams, known as stringers, located where the liquid hydrogen tank meets the intertank.

Cracked intertank stringers were identified during shuttle Discovery’s first launch attempt in November 2010 and delayed its launch until the problem was resolved. X-ray inspection of the intertank stringers provides additional confidence that there are no stringer cracks in Atlantis’ tank. The stringers located where the liquid oxygen tank meets the intertank were modified with extra material to add strength and do not require inspection.

The 12-day mission also will deliver an experiment designed to demonstrate and test the tools, technologies and techniques needed to robotically refuel satellites in space, even satellites not designed to be serviced. The crew also will return an ammonia pump that recently failed on the station. Engineers want to understand why the pump failed and improve designs for future spacecraft.

Chris Ferguson, a veteran of two previous shuttle missions, will command the flight. Doug Hurley will serve as the pilot, a role he filled on STS-127 in 2009. Sandy Magnus and Rex Walheim will be the mission specialists. Magnus spent 4.5 months aboard the station beginning in November 2008. Walheim flew on STS-110 in 2002 and STS-122 in 2008.

STS-135 will be Atlantis’ 33rd mission and the 37th shuttle flight dedicated to station assembly and maintenance. It will be the 135th and final mission of NASA’s Space Shuttle Program.

Source and photo: NASA