Space shuttle Endeavour's astronauts Wednesday took turns test-driving an armored tank around Complex 39 as part of their emergency training exercises in the Terminal Countdown Demonstration Test.

The tank would be used by the crew to escape the pad 39A bunker in a dire scenario during the space shuttle countdown. Wednesday's opportunity to familiarize themselves with the vehicle occurred in the fields adjacent to the launch site.

Commander Mark Kelly and pilot Greg Johnson also got some flight time in twin Shuttle Training Aircraft at Kennedy Space Center's three-mile-long runway to hone their skills. The modified Gulfstream jets mimic the flying characteristics of the space shuttle diving toward the concrete strip for touchdown.

Photo credit: NASA

Photos by NASA