A convoy of trucks passes a launch pad to the Vehicle Assembly Building's high bay 4 at NASA's Kennedy Space Center in Florida.

A convoy of trucks passes a launch pad as it makes the journey from Port Canaveral, Fla., to the Vehicle Assembly Building's high bay 4 at NASA's Kennedy Space Center in Florida. The trucks carry Ares I-X upper stage simulator segments. The upper stage simulators will be used in the test flight identified as Ares I-X in 2009. The Ares I-X test flight will provide NASA an early opportunity to test and prove hardware, facilities and ground operations associated with the Ares I crew launch vehicle. It also will allow NASA to gather critical data during ascent of the integrated Orion crew exploration vehicle and the Ares I rocket. The data will ensure the entire vehicle system is safe and fully operational before astronauts begin traveling to orbit. The simulator segments will simulate the mass and the outer mold line and will be more than 100 feet of the total vehicle height of 327 feet. The simulator comprises 11 segments that are approximately 18 feet in diameter. Most of the segments will be approximately 10 feet high, ranging in weight from 18,000 to 60,000 pounds, for a total of approximately 450,000 pounds. Photo credit: NASA/Cory Huston