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. This system will take the astronauts directly to the bunker door.

An artist's concept of the Ares I launch pad shows the new evacuation system on the right. Astronauts and ground crew could leave the capsule and ride a rail car to a bunker for protection. The path would be marked with yellow and black arrows. Credit: NASA

Scott Colloredo, NASA's senior project integrator for Constellation ground systems, said the group called on the world's roller coaster designers for help with the concept.

"It's obviously not a thrill ride, but we're taking advantage of technology that's there," he said.