Shuttle start delayed until spacewalk fix

A camera on Alpha snapped this picture of the Progress supply ship as it closed in on the space outpost.

By Richard Stenger
CNN Sci-Tech

(CNN) -- The launch of the space shuttle Endeavour will be postponed until at least Tuesday to give space station crewmembers a chance to float into space and perform repairs outside their orbital home.

Shuttle flight engineers scrubbed tentative liftoffs on Thursday and Friday after a Russian cargo ship failed to dock properly with the station.

NASA managers expressed concern that, should the shuttle now attach to the station, the unmanned Progress vessel, which is "soft-docked" to another part of the station, might shake and damage the multibillion dollar modular complex.

VIDEO Space station Alpha commander Frank Culbertson describes the docking of a Russian cargo ship to Mission Control in Houston (November 30) Play video (QuickTime, Real or Windows Media)

Ground controllers in Moscow think a stray cable or wire somehow worked its way into the docking mechanism. The obstruction is preventing hooks and latches from fully engaging to fasten the supply ship to its docking port, space agency officials theorize.

"The decision to reschedule was jointly made after Russian and American flight controllers conducted an extensive review of the amount of work required to complete the mating of the Progress to the station," NASA said in a statement Friday.

Two Russian residents of Alpha are now preparing for a Monday spacewalk to remove the debris and secure the Progress to the station.

The new shuttle departure time was set for 5:45 p.m. EST on Tuesday, provided that the spacewalkers succeed on their makeshift repair job.

Alpha crew waits for a ride home: Mikhail Tyurin, left, Frank Culbertson, center, and Vladimir Dezhurov.

The Progress, which arrived on Wednesday, contains about 1.5 tons of supplies, none of which can be delivered until the vessel is tightly docked.

Col. Sam Dick, a U.S. Air Force officer in charge of security for the NASA mission, said the delay would not compromise safety during the launch, the first since the September 11 terror attacks.

The military has taken unprecedented steps to protect the $2 billion orbiter. Fighter jets and attack helicopters have increased patrols over Kennedy Space Center.

Endeavour waits on Florida launch pad.

Air, boat and automobile traffic around the Florida spaceport will be subject to the tightest restrictions ever on launch day.

Endeavour and her four-person crew will ferry three new residents to Alpha. When they return after a 12-day flight, they will bring home the current Alpha inhabitants, a trio that will have spent four months in space.

The orbiter's payload consists of more than 2 tons of supplies, including food, hardware, experiments and thousands of miniature U.S. flags, which will be given to relatives of those who died in the September attacks.