As expected, NASA space station managers and their Russian colleagues agreed this week to delay launch of the Russian service module from mid-November to no earlier than Dec. 26 because of shuttle delays and additional work to ready the critical module for flight, reports CBS News Space Consultant Bill Harwood.
The service module launch window extends to Jan. 16 and an official launch date will be set after a general design review late this month or early next.
The service module, already running more than a year behind schedule because of funding-related work slowdowns in Russia, will provide the international space station's initial living quarters and the propulsion needed to keep the outpost at a safe altitude. The module had been scheduled for launch from the Baikonur Cosmodrome in Kazakstan around Nov. 12, although NASA sources said a variety of technical issues including software testing and acoustic modifications remained to be completed.
The service module, similar in size and function to the core module of the Mir space station, is crucial to the initial assembly of the station and subsequent U.S. flights cannot be launched until the Russian module is in orbit. But NASA has had its own problems this fall, primarily due to time-consuming repairs of wiring defects in its fleet of space shuttles and interruptions caused by Hurricane Floyd.
So far, the shuttle launch schedule has suffered a two-month interruption and as a result, NASA and Russian managers agreed this week to delay launch of the service module to late December at the earliest.
NASA originally hoped to close-out 1999 with three shuttle missions: A September launch to map Earth with high-resolution radar; a mid-October visit to the Hubble Space Telescope; and a December flight to deliver supplies to the space station. By that point, the service module was to have been in place.
The plan then called for launch of a U.S. truss element on Feb. 24 followed by the arrival of the first full-time three-man crew around March 12. After that, NASA hoped to launch a large solar array section in late March followed by the U.S. laboratory module, Destiny, in late April. The next three-person station crew then would be launched in late June.
But that schedule, already facing delays because of technical problems with NASA's lab module, went out the window after the shuttle Columbia's launch July 23. A short-circuit five seconds after liftoff prompted a fleet-wide wiring inspection that turned up scores of defects. Shuttle program manager Ron Dittemore ordered repairs and it quickly became obvious the December station supply mission aboard the Atlantis would slip into early next year.
The wiring repairs, which are not yet complete, and delays caused by Hurricane Floyd forced NASA to delay the Hubble servicing mission to around Nov. 19 and to push the radar mission into December. But that schedule assumes: A.) the wiring issues are resolved in time; B.) that engneers can fix problems with a slightly corroded propellant valve in Discovery's right-side maneuvering rocket pod; and C.) that additional valve inspections don't turn up additional problems.
It will be difficult for NASA to get two missions off by the end of the year and the radar flight, at least, easily could slip to mid January. These flights could impact the station assembly schedule because Discovery must be turned around for station flight 3A and Endeavour for 4A. And so it goes.
NASA and Russian planners are still discussing when to launch the first station crew - Bill Shepherd, Yuri Gidzenko and Sergei Krikalev. If the crew launches in March, its Soyuz ferry craft would be in orbit longer than the allowed 180 days before the second crew arrives in late September. In that case, a so-called caretaker crew would have to be launched next summer to deliver a fresh Soyuz and to bring the old one home before it exceeds its certified orbital lifetime. This is a costly option for the Russians and NASA sources say it's more likely the first crew will take off in April instead of March, thus avoiding the Soyuz lifetime issue.
By Bill Harwood