After the Lift and Mate in the Vehicle Assembly Building the Orbiter, External Tank, and SRBs (known as the Stack) are mounted on the Mobile Launch Platform and further prepared for flight in the shelter of the huge hanger.
This time the Atlantis Stack was ready to go to the launch pad before the pad was ready to accept it so the rocket was held back in the VAB. Eventually the decision was made to Rollout Atlantis to the pad on the same night that Endeavour returned to the Shuttle Landing Facility.
The Rollout starts by manoeuvring the crawler underneath the Mobile Launch Platform with the stack on top and then hydraulically lifting it off the ground. The VAB hanger door is opened and the crawler started to haul the entire launch configuration out onto the crawlerway the is a specially constructed roadway leading from the VAB out to launch pads 39A and 39B.
Atlantis’s trip out to the pad this night was scheduled a few hours before Endeavour was due to land, making it a very busy night at Kennedy Space Center. About 8:40pm the diesel engines of the crawler revved up and shortly after the MLP with Atlantis on top started its first movement.
The full Rollout details and picture gallery follow:
The trip out to the launch pad takes several hours with a few stops on the way. The first stop was just outside the VAB hanger where hundreds of workers took the opportunity to once again wish the shuttle bon-voyage. As the Space Shuttle emerged from the VAB the rocket was lit by a pair of xenon spotlights pinpointing it on the trip to the pad. There were a couple of additional stops on the way to LC-39A where the bearings of the crawler were greased to preventing them over heating.
Atlantis finally arrived at the pad and was classified as ‘soft down’ just in time for STS-134 Endeavour to return to the Shuttle Landing Facility. The term soft down means that the MLP has been lowered onto the launch pad. Hard down is when the MLP has been locked down onto the pad with the crawler removed.
Now that the rocket has been delivered to the pad more preparations for flight take place, this includes the delivery of the payload to be installed in the payload bay prior to launch.