The crew of a Pacific Southwest Airlines jetliner involved in the nation's worst aviation accident had lost sight of a small plane it later collided with moments after telling air controllers the craft was in view, according to previously undisclosed cockpit tapes.

Vhe 135 people aboard the 727 jetliner, both persons in the single-engine Cessna and seven on the ground died when the aircraft collided about 3,000 feet over San Diego on Sept. 25.

Both planes were destined for Lindbergh Field, about three miles east of the collision site. The 727 had been warned by the airfield's control tower that the smaller plan was in the area.

"Traffic in sight" the PSA jet radioed back, about 90 seconds before the collision. "Think he's passing off to our right."

But in the cockpit, one crew member asked another, "Do you see him?"

"He was right over there a minute ago," came the reply.

"He's probably behind us."

Alan Saville, the controller handling the PSA plane, said he assumed from the radio reply that the Cessna was in the pilot's sight.

"If he has said 'Where is he now?" or a flat 'Not in sight,' I would have dropped everything," Saville said.

The National Transportation Safety Board, which has possession of the cockpit tapes, has not announced its findings about why the two aircraft collided in a clear morning sky. The Los Angeles Times reported the cockpit comments yesterday based on conversations with persons who have heard the tapes.