There hasn't been an emergency on the launch pad that required the use of an emergency evacuation system for astronauts but, to be safe, NASA has updated earlier systems of escape for Launch Complex 39B, hosting the new Orion spacecraft and Ares I rocket of the Constellation Program, which were basically cables running from the spacecraft’s crew level to an area near a bunker, to one with rails. And linked cars. 380 feet above the ground.
Yes, it is the most spectacular roller coaster around, and we will never get to ride it.
Kelli Maloney, lead designer for the launch pad escape system, said requirements call for astronauts to be able to get out of the spacecraft and into the bunker within 4 minutes.