Re: WHY DO SPACE SHUTTLE ASTRONAUTS WHERE PARACHUTES DURING TAKE OFF?

Bruce,

This is a question I hadn't thought of before. Common sense suggests you are correct that it would not be possable to use parachutes on take off and landing even if there was an emergency. In fact NASA says:

The in-flight crew escape system is provided for use only when the orbiter would be in controlled gliding flight and unable to reach a runway. The crew escape system provides the flight crew with an alternative to water ditching or to landing on terrain.

There are actually four options, or "intact aborts" as NASA calls them, a shuttle crew might take in the case of an emergency during take-off: abort to orbit, abort once around, transatlantic landing and return to launch site. In each of these situations, the crew would have control of the shuttle, though they might not have control of where they can land, thus the parachutes.

Here's a link to NASA's pages on the subject.
http://www.ksc.nasa.gov/shuttle/technology/sts-newsref/s tsref-toc.html#mission_profile

Mike Francis
http://www.gis.net/~mtf/sm.htm