Crew of Space Shuttle Columbia Begin Spacewalk To Test $3 Million Robotic CameraBy MICHELLE KOIDIN

SPACE CENTER, Houston (AP) _ Two astronauts floated out the hatch of space shuttle Columbia today to test space station equipment during a spacewalk added by NASA only two days ago.

Winston Scott and Takao Doi went outside for the second time in nine days to spend more time using an extendible, 17 1/2-foot crane and to try out a free-flying robotic camera.

The crewmen trained for the tasks before their mission began Nov. 19 but couldn't conduct them during last week's planned spacewalk because they had to chase a runaway science satellite.

With the satellite back on board for Friday's trip home, and with space station construction just half a year away, NASA quickly and eagerly made arrangements for the second outing. No other spacewalks were planned before the first assembly flight next June.

Because the satellite rescue took up almost half of the 7 1/2-hour outing on Nov. 24, Scott and Doi didn't have time to use the crane to lift a 50-pound object or to release the prototype camera. Scott did work with a 350-pound box, but he had difficulty latching it onto the end of the crane _ a problem that increased the space agency's desire for another spacewalk.

A crane similar to the one tested by Scott and Doi will be used all the time to move objects outside the space station. The crane was supposed to be tested by two other spacewalkers last year but their excursion was canceled when the hatch on Columbia got stuck.

NASA hopes to send an upgraded version of the camera, called Aercam Sprint, to the station. It could examine hard-to-reach areas outside, cutting down on the number of spacewalks needed for maintenance.

The $3 million, beach ball-sized unit _ padded for safety _ was to flutter around the open cargo bay, its video camera watching the spacewalkers. The 35-pound, jet-propelled sphere was to be operated by remote control by shuttle pilot Steven Lindsey.

The space station, which will take five years to assemble, will require more than 1,150 hours of spacewalks by Americans alone. Russian cosmonauts will spend half that amount of time spacewalking.

During their first spacewalk, Scott and Doi stood in the shuttle's open cargo bay and caught the $10 million Spartan satellite with their gloved hands.

The spacecraft malfunctioned right after its release on Nov. 21 because it never got a critical computer command. The crew then tried to capture it but accidentally bumped it with the shuttle's robot arm and sent it into a slow spin.