NTSB Investigation: Contact of towing vessel John 3:16 with pier
No pollution or injuries were reported. The final cost to repair the damages to the towing vessel and pier was $285,441.
No pollution or injuries were reported. The final cost to repair the damages to the towing vessel and pier was $285,441.
The incident
While transiting the Lower Mississippi River near Saint Rose, Louisiana, the John 3:16 contacted an industrial cargo pier. Following the casualty, the pilot tested negative for alcohol and other drugs, and no issues were noted with the vessel’s steering or propulsion systems. Additionally, the pilot did not experience any challenges related to weather, visibility, or river conditions.
The pilot’s cell phone records indicated that he was using his phone while operating the vessel. However, the records showed there were no text messages or phone calls (incoming or outgoing) in the 30 minutes leading up to the contact at 0641, and therefore the pilot was not distracted by cell phone use immediately prior to the contact.
The pilot noted that he was dealing with personal stressors in the days before the contact. These stressors resulted in increased cell phone use during his off-watchtime. The pilot reported receiving 3 hours of continuous sleep during his 12 hours of off-watch time before the casualty. However, a review of the pilot’s cell phone records during these 12 hours indicated that the longest period between either a sent text message or a connected phone call (indicating some action on the part of the pilot and that he was awake) was only 2 hours. Therefore, because of his cell phone use during his off-watch time, the pilot had an opportunity for less than 2 hours of continuous sleep before taking the casualty watch.
Following the contact, the pilot told the port captain that he fell asleep. Individuals typically require 7–8 hours of sleep in each 24-hour period to avoid the
negative performance effects of fatigue. Fatigue is the human body’s desire for sleep and impacts all aspects of human performance. A deficit of as little as 2 hours can result in acute sleep loss and associated performance decrements, including decreased attention, slower reaction time, reduced vigilance, poor decision-making, and an inability to stay awake. While there are differences in the hours of sleep that an individual may require to feel “well-rested” (the pilot noted that he normally received 5 hours of sleep), the pilot had accumulated a significant sleep debt, having likely received less than 5 hours of sleep combined over the 2 days before the contact. This is less sleep than what the pilot typically received, and significantly less than the recommended 7–8 hours of sleep for each 24-hour period needed to avoid fatigue-related performance impacts. Therefore, the pilot had accumulated an acute sleep debt in the 2 days before the casualty, which resulted in the pilot falling asleep while on watch, leading to the vessel’s contact with the pier.
Conclusions
Probable Cause
The National Transportation Safety Board determines that the probable cause of the contact of the John 3:16 with an industrial cargo pier was the pilot falling
asleep while navigating due to an accumulated sleep debt. Contributing to the pilot’s fatigue was cell phone use during off-watch time, which significantly limited the pilot’s opportunity for sleep.
Lessons Learned
Maximizing Sleep during Off-watch Rest Periods
Fatigue is often a factor in casualties investigated by the NTSB. Fatigue affects all aspects of human performance, including decision-making, alertness, and reaction time, all of which affect a mariner’s ability to safely navigate a vessel. Mariners should understand the performance effects of sleep loss and recognize the dangers of working on board a vessel while fatigued. Individuals typically require 8 hours of quality sleep each 24-hour period to avoid the performance effects of fatigue. A sleep deficit of as little as 2 hours can result in performance decrements caused by acute sleep loss. Obtaining quality, uninterrupted sleep on board a vessel is often challenging due to shipboard environmental factors and external distractions such as cell phones. It is important that mariners get enough sleep during each off-watch period, so they remain alert when assuming watch.