Tanker Overseas Reymar allision with San Francisco‒Oakland Bay Bridge

The National Transportation Safety Board (NTSB) has published a Marine Accident Brief regarding the allision of the tanker Overseas Reymar with the fendering system of the San Francisco-Oakland Bay Bridge's Echo tower.

On January 7, 2013, at 1118 local time, the 752-foot-long tanker Overseas Reymar allidedwith the fendering system of the San Francisco‒Oakland Bay Bridge's Echo tower. The vessel wasoutbound in San Francisco Bay. No one was injured and no pollution was reported. Damage to thevessel was estimated at $220,000, and the cost to repair the Echo tower's fendering system wasestimated at $1.4 million.

That morning, the pilot awoke about 0600 and checked his duty status with the San FranciscoBar Pilots Association. He learned that he was scheduled to pilot the tanker Overseas Reymar for anestimated 1100 departure. He reported to the pilot station about 0930‒0945 to allow sufficient timefor departure preparations. After boarding the vessel at Anchorage 9, the pilot and the masterreviewed vessel-related information and the passage plan. The pilot informed the master that heintended to transit through the Charlie-Delta (CD) span of the San Francisco‒Oakland Bay Bridge("Bay Bridge"), and the master agreed.

The CD span is 1,079 feet wide; the adjacent Delta-Echo (DE) span is more than twice aswide, 2,210 feet. Watchstanders with the US Coast Guard's San Francisco Vessel Traffic Service(VTS) indicated that 80‒90 percent of vessels transit through the wider DE span.

A section of the Bay Bridge, with towers and pier marked.

A section of the Bay Bridge, with towers and pier marked. (The photo is taken from the northwest,looking southeast. The western-most tower, Alpha, is not visible in this photo.) The CD span runsbetween the Charlie pier and the Delta tower. The DE span runs between the Delta and Echotowers.

(Image Credit: NTSB Report on Allision of Tanker Overseas Reymar withSan Francisco‒Oakland Bay Bridge)

At 1044, the pilot reported to VTS that he and the crew were preparing to get the shipunder way and that they would transit through the CD span. At 1054, the master ordered theanchor heaved, and the vessel began its transit shortly thereafter. VTS asked the pilot to reportthe visibility, and the pilot responded that it was about half a mile, but, as he later toldinvestigators, the visibility was "going in and out" or increasing above and decreasing below halfa mile as the transit continued. (Meteorological data indicate that the visibility at the time of theallision was about one eighth of a mile near the bridge.)Both the pilot and the master told investigators that, as the Overseas Reymar continued itstransit, the visibility decreased to less than a quarter of a mile. About the same time, the pilot, whowas using both visual cues and vessel radar for navigation, realized that the return from theRACON, or "RAdar beaCON" on the CD span was not displaying on the vessel's radar screens.

The RACON, a transponder that responds to radar interrogations, identifies the center of the span.Caltrans, the California state agency that oversees the Bay Bridge, installed three RACONs on thebridge; in addition to the CD span, the Alpha-Bravo (AB) and DE spans are equipped withRACONs. Although not required by Coast Guard regulations, RACONs have become one of manytools mariners rely on when operating in reduced visibility. Caltrans personnel learned after theaccident that the CD span RACON was out of service.

The pilot initially selected the CD span because he anticipated encountering reducedvisibility (as he told investigators, he regularly used the same course when departing fromAnchorage 9 because he would "see the same thing again and again"). Familiarity with a routefacilitates a pilot's ability to recognize deviation from a planned course, an important factor toconsider when transiting waterways in challenging conditions. And, although the CD span is lessthan half as wide as the DE span, its width is sufficient for vessels even larger than the OverseasReymar to safely complete the transit.

Despite the pilot's familiarity with the CD span, his navigation plans werebased on the RACON identifying the center of the span on the vessel's radar. When thisnonfunctioning RACON did not display, the pilot appears to have seen no other alternative thanto choose another span with a functioning RACON. Yet marine safety depends on marinersbeing sufficiently prepared and "ahead of the vessel" so that the loss of a single navigational aid,despite its criticality, does not jeopardize safety.

The master's phone conversations during a critical navigation phase-while thevessel was in a confined, complex waterway in reduced visibility-degraded the safety of thevessel's transit. Although the pilot serves as the waterway expert, the master is the vessel expert.Masters and pilots, working together, are integral to effective vessel team performance. Theyassist one another by verifying or providing waterway and vessel information. By removinghimself from the team because of his phone conversations-which should have been postponeduntil the vessel entered a less demanding phase-the master was unable to assist and oversee thepilot effectively. Consequently, he was not in a position to recognize that the vessel was nolonger on a safe course.

Propable Cause

The National Transportation Safety Board determines that the probable cause of theOverseas Reymar allision with the San Francisco‒Oakland Bay Bridge was the pilot's decisionto alter course from the CD span to the DE span without sufficient time to avoid alliding with thebridge's Echo tower, and the master's failure to properly oversee the pilot by engaging in aphone conversation during a critical point in the transit.

For more information, please read the NTSBMarine Accident Brief onSF Bay allision