According to Parsons the planning window for the launch of STS-114 - the so-called "Return to Flight" mission - has been moved to extend from 12 September 2004 to 10 October 2004. Whether the launch happens at the opening of this window depends on lighting conditions. Parson noted that this window may well be adjusted at a later date.

STS-114 will not be a crew rotation flight as had been planned earlier. Instead, this flight will now be a "developmental" flight which will seek to demonstrate a number of improvements and modifications to hardware and procedures made in the aftermath of the Columbia accident.

Due to the addition of a number of new tasks, STS-114 will be a "logistics" flight - not a "logistics and utilization" flight as had been originally planned.

STS-114 will be followed by STS-121 which will be designated ULF1.1 STS-121 has a target launch date of 15 November 2004. Both STS-114 and STS-121 will carry an MPLM - Multipurpose Logistics Module.

Parsons and Readdy admitted that many challenges lay ahead in meeting these target dates. "This is going to be a long uphill climb to return to flight" said Parsons.

Last month, in announcing its Return to Flight Plan, NASA announced that it had set 11 March 2004 as a "no earlier than" launch date for the next Shuttle mission. At the time NASA Administrator O'Keefe said there would be an important driver for this launch date: the ability of the ISS logistics and integration schedules to be met - and a suggestion that there could well be slippage in this date if either driver was not met. O'Keefe said that everyone in the agency needs to know that the schedule is flexible.

NASA has a practice of working towards specific milestones - such as a launch date. Without having an agreed to point at which a variety of tasks need to be accomplished, you'd have programmatic chaos with everyone working to a different timeline - with processes that have specific and interlinked sequences totally out of synch. Sometimes things proceed toward a specific deadline even when there is some growing doubt that the date can be met. The logic being that you strive to get the system as close as you can to meeting the established date - and wait and see what prevents you from doing so. Then you slip the date. Sometimes the working dates can seem wildly optimistic - even implausible. Yet the program keeps working towards that date until program managers provide some 'schedule relief'.

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