NASA, which once promised that a space shuttle would launch every two weeks (six flights a year by four spacecraft) now plans to launch only four manned missions per year. The problem is the liquid-fueled main engine, which must be completely rebuilt after each flight. (NASA convinced Congress to buy the shuttle by insisting that the engines would need no more service than those of an airliner. The problem is that NASA runs its engines at 105 percent of their rated power, while airliners, and the cancelled Delta Clipper spacecraft, run their engines at 50 percent.)

NASA will also change the way it does its accounting. In the past, shuttle flights were charged to the "manned spaceflight account" and the program which the flight supported was charged only for any extra costs directly linked to that program. Now, any flight to support a given program (e.g., the Hubble Space Telescope, or a satellite launch) must be funded by that program. --Stephen V Cole