The National Transportation Safety Board said late Sunday that the submarine USS Greeneville made at least two periscope checks and a passive sonar sweep in the moments before it collided with the Japanese fishing vessel Ehime Maru on Friday.

The Greeneville struck the Ehime Maru while making an emergency ascent out of the water about nine miles south of Diamond Head.

"We were told that a periscope search was made, and the submarine ascended a few feet higher, closer to the surface and that another periscope search was completed," NTSB Investigator John Hammerschmidt said. "But I want to emphasize that's what we were told this morning, a very brief synopsis of what the Navy could tell us."

NTSB investigators arrived on Oahu Saturday.

Hammerschmidt said that his investigators will start interviewing crew members aboard the Greeneville on Tuesday. He said that there are no plans to interview a number of civilians who were also aboard the Greeneville on an orientation trip at the time of the collision.

Hammerschmidt would not say if the Greeneville's maneuver was a routine exercise or being conducted for the visitors' benefit.

Hammerschmidt also said that the NTSB has no plans to salvage the Ehime Maru because he does not believe it is crucial to the investigation.

Previous Stories:

• February 11, 2001: Search For Ehime Maru Victims To Continue
• February 11, 2001: Captain Of Ehime Maru Speaks
• February 11, 2001: Government Calls Submarine Collision 'Tragedy'
• February 10, 2001: Sub Commander Reassigned As Search Continues
• February 10, 2001: U.S. Offers Another Apology To Japan
• February 10, 2001: Anxiety Turns To Anger In Japanese Town
• February 10, 2001: Sub Collided During Emergency Maneuver