CAPE CANAVERAL, Fla. -- The STS-135 crew sign their names to an Atlantis flag at the conclusion of their M113 armored personnel carrier training at NASA's Kennedy Space Center in Florida. Seen here are Mission Specialist Sandy Magnus (right) and Commander Chris Ferguson. An M113 is kept at the foot of the launch pad in case an emergency exit from the launch pad is needed and every shuttle crew is trained on driving the vehicle before launch. The STS-135 crew is at Kennedy to participate in a launch countdown dress rehearsal called the Terminal Countdown Demonstration Test (TCDT) and related training. Atlantis and its crew are targeted to lift off July 8, taking with them the Raffaello multi-purpose logistics module packed with supplies and spare parts to the International Space Station. The STS-135 mission also will fly a system to investigate the potential for robotically refueling existing satellites and return a failed ammonia pump module to help NASA better understand the failur