Video interactive reconstruction assists vindicating pilots in October 2011 collision on Houston Ship Channel.
A recent administrative hearing held at the Port of Houston by the Pilot Board Investigation and Recommendation Committee found no misconduct on the part of the ship pilots who were involved in the collision between the 59,277- DWT chemical tanker Elka Apollon and the 782-foot container vessel MSC Nederland on the morning of October 29, 2011 in the Houston Ship Channel (HSC). Following a closed door deliberation of the public hearing, the PBIRC recommended to the Pilot Board, that the case be closed to file. The board also acknowledged the emergency ship handling efforts of Captain Michael Riggle, the pilot in command of the MSC Nederland at the time of the collision, for successfully avoiding additional vessel damages and any personal injuries or pollution.
A report released by the National Transportation Safety Board last September determined that the probable cause of the collision was the inappropriate response of the pilot of the Elka Apollon to changes in bank effect forces as the vessel transited the Bayport Channel Flare, causing the vessel to sheer across the channel and into the MSC Nederland. The NTSB, which only has the authority to issue fact and causation findings and to make safety recommendations, also recommended that the Coast Guard develop and implement a policy to ensure an adequate separation between the many vessels transiting the Houston Ship Channel.
Two separate computer simulations depicting the sequence of events just prior to the collision were presented to the PBIRC as evidence: one provided by the NTSB; and the other constructed by Captain Brian Boyce, USN (Ret.), an expert in computer generated maritime simulations.
Both videos show that, just after 0900 as the outbound Elka Apollon and the inbound MSC Nederland approached at approximately a half mile from each other in a position located just north of a slight bend in the ship channel at beacons 75 and 76, a third vessel the utv Mr. Earl, pushing a single fuel barge converged out of the Bayport Channel. On a morning that Vessel Traffic Services in Houston had over 100 vessels checked into its system, the southbound Greek-flagged tanker Elka Apollon filled with naphtha, and piloted by Captain Paul F. Dunaway approached the Bayport Channel from the north while transiting the HSC.
The Bayport Channel intersects the Houston Ship Channel from the west at a ninety-degree angle. The Bayport Channel forms a V shape, or flare (Bayport Flare), at the intersection to allow traffic to funnel in and out of that Channel.
Captain Riggle, who was bound for the container terminal in Bayport aboard the MSC Nederland, slowed his vessel to meet Captain Dunaway just below the HSC’s turn at 75 and 76 beacons on a one whistle passing (port to port). This turn is just below the Bayport Flare.
Captain Dunaway, a 22-year HSC pilot, stated in his interview before USCG and NTSB investigators that prior to reaching the intersection of the HSC and the Bayport Channel, his Automated Information System (AIS) unit showed that the slow moving Mr. Earl, making 2.7 knots, presented no risk of collision. As the respective videos reach the 09:02:10 mark, the simulations show Captain Dunaway starting to initiate his turn to starboard and moving Elka Apollon farther to the green side of the channel (with a “Starboard 20” command) to facilitate a port-to-port passing with the Nederland and shape up for the next leg of the Channel.
The NTSB Simulation incorporated selected excerpts from Elka Apollon’s Voyage Data Recorder (VDR), a system that collects data from various sensors on board ships and is equivalent to the “black box” found on airliners.
The bridge audio from the VDR recorded Captain Steve Hill, the non-conning pilot of the Elka Apollon, alerting Captain Dunaway that Mr. Earl was getting ready to hit Elka Apollon’s starboard quarter.
Hill is heard saying “What is this guy doing?” The video continues in conjunction with the audio, recording a very composed Captain Dunaway trying to check up his vessel’s rate of turn to starboard by ordering the rudder port twenty while also communicating passing agreements over the VHF with the two tows ahead of him, the Uncle Nu and the Paddy.
At 09:02:54 and just minutes before the collision with the Panamanian registered container ship, MSC Nederland (northbound in the HSC), the NTSB video shows Captain Dunaway easing the rudder to port (“Port twenty”).
At 09:03:41, Captain Dunaway is heard on the accompanying VHF recorded audio warning the Mr Earl; “Mr Earl, don’t squeeze over here. I’m getting ready to – my stern’s getting ready to come your direction. Mr. Earl replies“ Right, yeah, squeezing over.” Directly after this VHF transmission the recorded data position of the tow vessel Mr. Earl is inexplicably lost in the NTSB video.
Recordings show that Captain Dunaway never changed the position of the rudder from port twenty to midship until 09:03:54, a full minute after originally ordering the port twenty wheel order. It is during this critical one minute juncture where the version of events as chronicled by the NTSB and the reconstructed animation prepared by Captain Boyce diverge. The Boyce video clearly shows Mr. Earl increasing speed to 6.0 knots in the Bayport Flare and at 09:03:09 turning to port towards the Elka Apollon while nearly colliding with the Elka Apollon’s starboard quarter. Conversely, the NTSB video, shows the operator of the Mr. Earl making a seamless turn from the Bayport Channel into the ship channel and paralleling the course of the outbound Elka Apollon. While the narrator of the NTSB video openly acknowledges losing the position of the Mr. Earl during this time frame, what is far from clear is how the NTSB simulation continued to depict the physical aspect or alignment of Mr. Earl and its tow through this sequence. The NTSB video does not show Mr. Earl’s port turn into Elka Apollon.
Subsequently, in an effort to avoid the approaching MSC Nederland, at 09:04:06 Captain Dunaway ordered Elka Apollon’s helmsman to bring the wheel over to “Hard Starboard.” Despite the starboard rudder and the ship’s engine being rung up to emergency full ahead, Elka Apollon continued to swing to port and across the narrow ship channel towards the MSC Nederland. Meanwhile, although purportedly in a safe position in the ship channel as viewed in the NTSB video, at 09:04:16 the operator of the Mr. Earl can be heard over the VDR, “yeah ship we’re not looking too good buddy.”
At 09:05:26, the Elka Apollon struck MSC Nederland’s port side.
In a interview with Coast Guard investigators in November of 2011, Captain Dunaway stated that “I was going to use the right wheel. I wasn’t going to use any left wheel and hold my ship down in the bend, come around Captain Riggle and get back in the middle of the Channel, and Mr. Earl caused me to swing to port early and then I lost control.”
Keith Letourneau, the attorney representing Captain Dunaway, compared the rudder commands obtained from the VDR against Captain Boyce’s computer simulation, to demonstrate that at the very time Captain Dunaway would have applied starboard rudder to take the vessel deeper into the bend, Mr. Earl began turning into port into Elka Apollon.
Letourneau contended at the PBIRC hearing that the collision between the Elka Apollon and MSC Nederland would not have occurred had Mr. Earl not unexpectedly and without warning increased its speed in the Bayport Channel flare, turned to port toward Elka Apollon and embarrassed the navigation of the Elka Apollon, which was constrained to remain in the deep draft portion of the Houston Ship Channel. He further conveyed to the PBIRC members that the decisions made by Captain Dunaway were a direct consequence of Mr. Earl and its tow’s close-aboard approach to Elka Apollon. The NTSB failed to take into account how close Mr. Earl was to Elka Apollon, which changed the decision of the pilot in how to apply the rudder.
By contrast, the NTSB found that:
“Probable cause of the collision between the Elka Apollon and the MSC Nederland was the failure of the pilot conning the Elka Apollon to appropriately respond to changes in bank effect forces as the vessel transited the Bayport flare causing the vessel to sheer across the channel and collide with the MSC Nederland-NTSB.”
Formed in 1967 as the federal government’s primary accident investigation agency for all modes of transportation, the NTSB is not bound by the Federal Rules of Evidence it considers during the course of an investigation. Thus, it can consider testimony from any fact or purported expert witness without necessarily meeting the requirements of federal evidentiary rules or judicial precedent, or testing through the adversarial process. Critics of the NTSB investigation cite this structural flaw as a possible reason for the agency using a Kinematics Parameter Extraction Study prepared by D.A. Crider to reach numerous dubious conclusions about the effects of yawing and bank suction upon the Elka Apollon, which the agency claims causally contributed to the collision. A review of the study did not provide any details regarding Crider’s qualifications, education or engineering work experience in preparing the report, nor the underlying data relied upon by Crider.
As noted by one pilot who has piloted thousands of ships along the channel, “the government failed to take into account that there is no bank in the Bayport Flare.” Records also show that the while the joint Coast Guard–NTSB investigators asked for the post accident drug test results of the three pilots involved in the incident as well as documentation addressing how much rest each had during the days preceding the incident, Mr. Earl’s operator was never asked to submit similar records. At the hearing, Letourneau pointed out to the PBIRC members, that the Boyce video corroborates the sworn testimony of Captains Dunaway and Hill, who along with the 2nd mate of the vessel stated that when the Mr. Earl reached the Bayport Flare he altered course toward Elka Apollon’s starboard quarter.
Letourneau pointed out that Boyce relied upon the Coast Guard AIS recording to document Mr. Earl’s movements, the NTSB apparently failed to use this data, and the NTSB ignored the corroborating evidence of three witnesses – Captain Dunaway, Captain Hill, and Elka Apollon’s second mate – all of whom told Coast Guard and NTSB investigators that Mr. Earl’s tow was getting ready to collide with Elka Apollon.
Crider’s Parameter Extraction Study concluded that Mr. Earl’s close-aboard approach was not a cause of the collision, but failed to account for all of this evidence.
This article was written by an anonymous member of the Houston Pilots.