NTSB Releases Report On Houston Ship Channel Collision
Shortly after 4 a.m. on March 15, 2019, the mv. Dixie Vandal, traveling inbound on the Houston Ship Channel with a partially loaded fuel barge, struck the mv. Trinity and one of its two barges, which were moored at the Kinder Morgan Pasadena Liquids Terminal in Pasadena, Texas, near Mile 44 on the waterway. The Trinity was preparing to discharge cargo at the terminal. Both vessels were owned by Kirby Inland Marine.
The force of the impact caused the mv. Trinity and its tow to shift about 100 feet, which subsequently broke cargo hoses and mooring lines and damaged the facility. The National Transportation Safety Board (NTSB), which recently released its Marine Accident Brief detailing the incident, estimated total property damage at $630,230, with just under $520,000 of that to the terminal itself.
According to the NTSB report, the playback of the Dixie Vandal’s electronic charting system (ECS) indicated a sharp turn to port in the moments before impact.
“At 04:07:47, the rate-of-turn indicator on the electronic charting system reached its maximum display of 30 degrees to port,” the NTSB report said. “At 04:08:31, at a speed of about 6.5 mph., the forward port corner of [the Dixie Vandal’s lead barge] contacted the starboard side of the Trinity and then struck the forward port corner of the barge Kirby 29051.”
All 12 mooring lines holding the Trinity’s barges to the terminal parted, and two cargo hoses parted, releasing a half gallon of jet fuel into the channel. The Trinity, with damage to the starboard side of the second deck, was sold following the incident. The Dixie Vandal was not damaged. Both of the Trinity’s barges incurred damage. The NTSB report does not detail damage to the Dixie Vandal’s barge.
As to the cause of the incident, the NTSB investigation identified pilot fatigue as the likely culprit.
“After the incident, the pilot on the Dixie Vandal told investigators that he believed he had dozed off in the seconds before striking the Trinity and was awakened by the impact,” the report said. “He was unsure how the tow had turned to port.”
After the accident, alcohol and drug tests were administered, with all results negative. The pilot was also determined fit to continue his duties. At the time, the pilot had worked aboard the Dixie Vandal for two years, with close to 17 years total with Kirby. The pilot’s usual watch was from 6 p.m. to 6 a.m. At the time of the incident, he was on day 10 of a 20-day rotation.
According to NTSB, the 12-hours-on, 12-hours-off schedule aboard the Dixie Vandal had been in place for one or two years. A manager for Kirby said vessel watch schedules “were established by the vessels’ crews at their discretion,” as long as they didn’t exceed 12 hours on per day. The report notes that the Dixie Vandal switched to 6-hour watches following the incident.
The report noted that fatigue is a leading cause of incidents in the transportation industry, with fatigue-related incidents most likely to occur between the hours between 1 a.m. and 5 a.m. Regarding marine accidents, of the 14 marine accidents the NTSB investigated between 2014 and 2019 that involved fatigue as a major factor, “10 accidents occurred between 0100 and 0600.”
“Shift work adds more complexity to the circadian process, because individuals have a harder time acclimating when switching from a day shift (or in this case, off-duty) to a night shift, when a crew member’s entire schedule is flipped from day to night,” the NTSB said in the report.
The NTSB concluded that the probable cause of the incident “was the fatigued pilot falling asleep near the end of his 12-hour watch while maneuvering in the Houston Ship Chanel, resulting in the loss of control of the vessel.” Contributing factors, according to NTSB, were the length of the pilot’s watch and his use of cetirizine, an over-the-counter antihistamine.