The space shuttle is critically dependent on what we intend to do with the international space station and those requirements are still being worked out.

We have scheduled the 15th of May as our targeted launch date.

The reality is that we don't know how many flights are needed, if we're successful returning [the shuttle] to flight.

But it should be clearly understood that this is a 'not earlier than' date, which gives us the earliest opportunity we can bring all of the processing elements together and have a credible window to get to the international space station.

Early debris, early in the flight path, would be critical because that material would obviously be near the start of the events, ... It would clearly be very important to see the material earliest in the sequence.

We need additional technology to supplement manned aircraft surveillance and current ground assets to ensure more effective monitoring of United States territory.

If it is wing material, obviously that would be very important to the investigation. Early material in the debris field is extremely important to the early events of the recovery that would shed important light on what the ultimate cause was.