A pilot’s failure to account for bank-effect forces likely caused a 2011 collision between a tanker and a containership in the Houston Ship Channel, according to the National Transportation Safety Board (NTSB).
The Houston Pilots Association disagreed with the agency’s findings, claiming the accident was caused by a towboat that merged into the channel just before the collision.
The 799-foot tanker Elka Apollon was outbound in the Houston channel on Oct. 29, 2011, when it collided with the inbound 782-foot containership MSC Nederland near the intersection with the Bayport Ship Channel.
Pilots aboard each vessel made passing arrangements over radio, but as they approached, Elka Apollon crossed the channel’s centerline and struck the port side of MSC Nederland, investigators determined.
Containers are damaged aboard Nederland. The tanker Elka Apollon ended up with $1.5 million in damage after the 2011 accident. The National Transportation Safety Board recommends better vessel separation in the area.
“The conning pilot on the Elka Apollon did not appropriately respond to the varying hydrodynamic forces affecting the vessel during its transit of the Bayport Flare, resulting in the pilot’s inability to alter the Elka Apollon’s course sufficiently to avoid the collision with the MSC Nederland,” the report said.
Investigators said the narrow waterway, bank effects at the Bayport Flare and vessel traffic density at the time “increased the challenges in a waterway with a limited margin for error.”
The collision caused about $1.5 million in damage to Elka Apollon and $1.3 million to MSC Nederland. No injuries resulted.
The Houston Pilots blamed the accident on the towboat Mr. Earl, which entered the barge lane of the main channel pushing a fuel barge as Elka Apollon prepared to pass MSC Nederland.
“The NTSB spent a year investigating the collision and never even went aboard or investigated the towboat Mr. Earl, which caused the collision when it exited the Bayport channel pushing a fully loaded fuel barge into the path of the … Elka Apollon,” Capt. Robert Thompson, head of the Houston Pilots, said in a statement.
Investigators acknowledge that Mr. Earl should have waited for Elka Apollon to pass before entering the barge lane in the main channel. They found both parties should have communicated with one another to avoid a “close quarters situation.”
“However, the NTSB further concludes that, given that the Elka Apollon conning pilot’s rudder commands preceded his awareness of the Mr. Earl’s position and because hydrodynamic forces were already affecting the Elka Apollon’s course, the close-quarters situation that developed with the Mr. Earl was not a factor in the collision with the MSC Nederland.”
The accident highlighted piloting challenges and the need for appropriate vessel separation within the Houston channel’s tight quarters, according to the report.
The agency identified 14 “precautionary areas” in the Houston channel, which can be especially difficult to navigate or require special attention when passing. It suggested that they be marked on nautical charts as to be easily recognized.
“None of these 14 precautionary areas is identified on Houston Ship Channel navigation charts, and mariners may not be aware that these areas exist,” the report states.
Investigators also recommended mariners communicate with approaching vessels and “set optimal vessel speeds that allow for timely transit while maintaining safe passage given the channel’s limited margin for error.”
The NTSB recommended the U.S. Coast Guard develop a policy that ensures adequate separation between vessels operating in the Bayport channel and other high-traffic intersections.
A spokesman for Coast Guard Sector Houston did not return phone calls or e-mails seeking comment on the board’s recommendations.