All large ships will have them, usually they’re diesels since those can be started pneumatically.

Is that an answer to why emergency generators were needed while a ship was still leaving the harbor?

I think I understand your point about why ships need emergency backup generators. I was wondering why this ship needed its to work while it was just getting underway.

We seem to be talking past each other. Availability wasn’t my question. What might have interrupted this ship’s normal power at so critical a time as leaving port?

The report will tell us that, but anything that interrupted fuel flow to the main engine will do the job. Also, 90 seconds between mayday and collision pretty much rules out effective mitigation either by steering gear or dropping a hook or two since it takes time to power up or get enough chain on the harbor floor to slow the ship. At least the anchors don’t need power to be released.

The regulatory minimum is for emergency power to be up and running in 45 seconds. That includes starting the generator and doing the automatic power transfers. However, it’s not uncommon for those automatic systems to break. Per other video I’ve seen, the lights were out for 61 seconds. It’s possible that the steering was up again after the lights came on, but it’s also possible that something didn’t work.

NTSB is leading the investigation, and USCG is assisting. There won’t be any stones unturned. I expect that we’ll get a press release from NTSB in about a week giving the basic facts (these generators failed, steering was/was not restored, emergency power took this long to be reestablished, etc.). I’ve been on the wrong side of the table on one USCG/NTSB investigation, and I would call them tough but fair rather than merciless. That said, my work evidence toward the problem rather than the problem itself.

On the fuel front, I would expect that the straight diesel fuel they will run in harbor is less likely to cause trouble in the generator than the heavy fuel oil they’ll run offshore. But you can get weird issues with bad mixes, contaminated fuel, plugged filters, etc.

If the power outage had happened 5 minutes earlier or 5 minutes later, we’d be calling a fourth stupid thing where a containership piled up on the bank. Instead, it’s a tragedy. This will be a good time to be a tug builder. Unfortunately for the average investor, most tug operators and shipyards are privately held so they’re not open to the average investor.

The level of automation on a container ship combined with the basic job (go from here to there only) makes it possible to run with a crew of 22, whereas a tug has too many duties to automate like that.

It’s about what is normal. As I noted above the automation is significant so watches can be maintained remotely, however that presumes that the sensors work and the evaluation software works as it’s supposed to, alerting the watch team to respond. The bridge would have everyone there, however.

MV Dali’s scheduled voyage was 27 days. However they arranged their watches, the crew would be sleep-deprived.

I rode a tug from Maui to Oahu some years ago. The crew of six stood 8-hour watches, allowing for the master or a mate plus a seaman on each.

Scary thing was, the operator was short-handed, so the first mate boarded without a break from his previous trip.

Our trip, which should have taken around 30 hours, was lengthened by a tsunami, so we were about 50 hours on the water. As we came in, I overheard a conversation between the dispatcher and the first mate. He was asked to go out immediately on another voyage.

He said yes, of course. Triple time.

My take after watching the video is that when the lights flickered out, the ship was already off course and committed to hitting the bridge support. I would think it should have been lined up with the middle of the channel when it was still half a mile away — these rigs do not respond quickly to the helm, and a last minute maneuver would not have saved it. It would be revealing to see a radar plot of its actual course superimposed on a map of the harbor and the recommended ship channel. I suspect it had been off course for some time, possibly due to power-related glitches in the navigation systems, from which they couldn’t recover because of the subsequent power-related steering problems.

Thanks! Interesting — it actually was right in the channel (slightly north of center) and correctly aligned with 1/2 mile to go, but it kind of steered hard right as soon as the power went off. It looks to me like they had just applied right rudder to get it more centered when the power failed — that was just terrible luck. If the rudder had still been centered, they would have made some leeway (I have no idea of the wind, tide and current conditions) but they might have coasted straight through. Tragic.

It may have been a small rudder correction that got frozen by the power outage, or it may have been the influence of the propeller. I’m not 100% sure on larger boats, but on smaller ones the prop can definitely “walk” the stern around. Other explanations are out there too.

When power fails, the rudder will either stay where it is (more likely) or will shift back to centerline if the steering gear just freewheels (much less likely). It will not default to hard over one way or the other, since you almost always need power to push it to one side or the other. It wants to come back to centerline.

We don’t know what the estuary currents were doing, and that’s a key piece. Also, the reason for pilots is to provide the ability to dodge any shoals that the Patapsco River just made.

The NTSB/USCG report will discuss that point in detail.