A last-minute decision by the pilot of the oil tanker that hit a bridge in the San Francisco area last week may have been part of the accident's cause, experts said.

Pilot Guy Kleess decided to change course and head between a different set of towers under the Bay Bridge. This move made the ship more vulnerable to the current that cuts under the bridge. According to experts, he would have had less margin for error from the course change as he steered the Overseas Reymar.

"I don't know why he changed direction, and that sort of information will have to come out in the investigation," said Peter McIsaac, president of the San Francisco Bar Pilots association.

The accidental sideswiping resulted in more than $2 million in damage to one of the towers. But because the tanker was empty, no oil spilled into the bay.

The Coast Guard is investigating different possible causes for the accident, including human error and equipment failure (Kevin Fagan, San Francisco Chronicle, Jan. 15). -- JE