NTSB Warns Mariners of the Hazards of Sleep Inertia

Here’s the latest NTSB sleep joke:

They suggest waking up a half hour earlier to combat the effect of sleep deprivation.


Sleep inertia??

More like the 6 hour watch schedule strikes again.

Also. Am I wrong in thinking that he should have been able to judge whether he was moving forward while entering a lock by using the lock as a fixed reference for speed? GPS is great and all, but my eyeballs can tell me if I’m moving over the bottom should it fail at an inopportune moment and I’ve got a fixed item to observe.


Here’s the gCaptain post

The report:

Details of incident along with the NTSB’s determination of probable cause were published in Marine Investigation Report 22/09 released Tuesday.

8/4/4/8 is the best of all the different ones I have worked.

6/6 no good rest
12/12 too long in the chair
8/8 to much rolling changes


I wonder if the captain was operating from the center line controls?

According to the report the only visual clues for speed he had was watching the lights out the side window. The other source of information he was using was distance reports from the deckhands but the handheld radios were having problems.

It wouldn’t surprise me if there was in fact heavy reliance on GPS.

7/7/5/5 is used in the harbor tug sector and is generally much preferred to 6/6. Seems to help a LOT.


Maybe if he had a half-hour less sleep like the NTSB suggests he wouldn’t have hit the lock gate.

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The captain’s watch started at 0600 but he took the watch sometime before 0515. He actually could have taken more time to wake up and gotten more sleep.

The Captain probably had to get up early to make the lock.

Practice varies. In some places, the Captain does all the close quarters maneuvering whether it is his watch or not. In other places, it is assumed that the mate will do all the maneuvering on his watch.

Assumptions don’t always hold. There are great mates that might lack local knowledge for a particular maneuver. There are mates that cannot be left alone within sight of land or traffic.


The report doesn’t explicitly say what the practice was at that company but it seems to imply that both the captain and pilot were qualified to take the tow through the locks.

That the captain taking over was contrary to company policy only makes sense if that was the case.

For over 40 years medical experts have said a MINIMUM of 8 hours rest is needed for a person to perform optimally at any task. Realizing most people need to unwind after 8 hours work, eat a meal, contact family, etc., most recommend 10 hours rest. To this day it is ludicrous to think workers can man a 24 hour job with 2 people at their best ability. The ONLY people that thinks this is a good idea are the people paying them.Arguing whether 6/6 or 12/12 is better is avoiding the question. 4 on 8 off is great IF the base pay is enough so that you don’t need the OT to make a living. Accidents will continue as they have been for years and years due to fatigue. Some folks will die, commerce will be interrupted for a bit then, rinse/repeat.
Most of the folks I knew that worked 6/6 or 12/12 for over 30 years didn’t live past 70, many died before they were 60. I don’t think that’s a coincidence.


Not many mariners have a choice as to the number of watchstanders.

From the point of view of safety the most common hazard of 6 on / 6 off is sleepiness at the end of 00-06 watch.

The issues in this case evidently is sleep inertia or grogginess. Similar but the difference is that sleep inertia will diminish over time at the beginning for the watch but sleepiness at the end of the watch only gets worse.

It matters on the margin.

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Sleep inertia…? :roll_eyes:

Back when paper charts were a thing, a typical captain’s excuse for grounding in narrow channels was, “I was looking at the chart”. Implying, the captain was looking so intently at the chart that he lost focus on the big picture. Highly implausible, but it had the effect of making the captain seem virtuous even when they screwed up…

I’ve never heard a captain say, “I just plain screwed up,” or “I wasn’t paying attention,” etc. after a grounding or other accident. Kind of like I’ve never read an obituary that said, “John was an SOB and we all knew it”. In obits, everyone is a saint, just as in accidents captains are always paragons of duty–even if they aren’t.

So when I come across reports like this NTSB one I don’t pay too much attention, because I know from experience they depend in part on testimony from officers with a vested interest to lie. Not every officer in every single case. But enough to make a statistical case for the hazards of “sleep inertia” problematical.

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What work schedule do your captains work?

Mostly 4-and-8. When second mates aren’t available they work 6-and-6.

More detailed answer: Only one out of five of our boats legally needs two mates, but we man the rest with two mates nevertheless, when available. For example, in 2020 nearly every voyage had two mates. During the Great Resignation in 2021 that was a struggle, but we found enough in 2022 to make the 4-and-8 pattern predominate.

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The first thing that a captain needs to do in that situation, accept responsibility. Only after that explain what the factors were.

An experienced captain should know that.

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Accept responsibility, but [vestigial lawyer speaking] don’t say “I screwed up” out loud. While it’s hearsay and hearsay is generally inadmissible in Court, it’s a “statement against interest” and is admissible.


Ahh the government is back to help! Oh you’re tired? Well then we suggest waking up earlier to combat the effects of not getting enough sleep…you’re welcome!


The only thing a captain should say is:

“I respectfully decline to make any statement until my lawyer from MOPS is present.”