The National Transportation Safety Board (NTSB) on Tuesday placed much of the blame on the pilot of the 105,000-dwt Elka Apollon (built 2005), which crashed into the 3,007-teu MSC Nederland(built 1992) on 29 October.

In an abstract of a new accident report, the agency said the probable cause was “the inappropriate response of the pilot of the Elka Apollon to changes in bank effect forces as the vessel transited the Bayport flare, causing the vessel to sheer across the channel and into the MSC Nederland”.

In addition to bank effects the NTSB believes other factors like traffic density, the width of the waterway, vessel speed and inadequate communication between the tanker and a nearby tug called the Mr Earl “increased the challenges in a waterway with a limited margin for error”.

“The timing of the rudder commands of the pilot of the Elka Apollon suggest that the close-quarters situation that later developed with the Mr Earl was not a factor in the collision with the MSC Nederland,” the agency added in a statement that followed today’s NTSB meeting.

As we reported, the Elka Apollon was travelling outbound and sustained damage in an area near its port bow from the crash and falling containers while the inbound MSC Nederland took the brunt of the blow portside at the main deck level in the vicinity of its superstructure.

The containership's rescue boat was torn from its secured position and set adrift during the accident but no injuries or significant levels of pollution were reported aside from a small spill caused by hydraulic fluid that leaked from tractor equipment in a container.

In an earlier NTSB report, authorities said that prior to the collision pilots onboard both vessels agreed via VHF radio to a port-to-port passing right before the Mr Earl, pushing a fuel barge, exited the Bayport ship channel off the tanker's starboard side.

"The pilot on the Elka Apollon issued commands to avoid the towboat and barge with left rudder orders and in so doing set the tanker on a heading across and to the left in the channel," officials  said at the time.

The conning pilot on the tanker tried to regain control of the vessel with a hard starboard rudder order in an effort to avoid the MSC Nederland, which took evasive action of its own, but ultimately the vessels still collided in spite of the efforts of both pilots.

Today, the NTSB said damage was estimated at $1.5m for the aframax and $1.3m for the panamax and, looking forward, urged the US Coast Guard to develop and implement a policy to ensure mariners are aware of precautionary areas on the Houston Ship Channel.

An NTSB spokesman tells TradeWinds that a formal report will be published shortly. They note that drugs and alcohol, weather, aids to navigation, vessel propulsion and steering systems were not found to be factors in the accident.

Click HERE to see what the Houston Pilots Association had to say about the findings

The NTSB abstract, a definition of the 'bank effect', a map of the Channel and other features can be explored by clicking on the facts boxes located to the right of this article