With the White House and Congress pressuring NASA to reduce space station costs and construction delays, the agency felt compelled to adhere to a fixed shuttle flight schedule for station missions, which would affect non-station missions as well, the report said.

CNN: Shuttle not likely to fly by spring, experts say

The result: lower departure fees (the majors typically pay a fee to the regional for agreeing to a flight schedule that maximizes connection traffic pushed to their flights) that have tightened up profit margins for the little guys.

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