How does a ship lose power this way?

Main generator had to go down. Looked like they got it restarted, I'm not sure the emergency generator would have brought the external deck lights back on as happened. For a super container, that generator is 80 megawatts. There is black smoke at the same time the lights come back on, which is not good, but at least the power is online. It was too little, too late. The investigation will commence after search and rescue is called off.

Who has the son at the Merchant Marine Academy? It would be mostly academic, but maybe his son would have a little insight on this.

Some in one of the Twitter threads was worried that the DEI blamers would be showing up in the thread in due time. It might not have anything to do with this accident, but one shouldn't be surprised that a policy of focusing on other qualities besides merit will be seen as a likely cause.

My son texted me from the Academy this morning, “Ladies and gentlemen this is what we in the industry would call a horrible day.”

Unfortunately, it's not an unusual one. From 1960-2015 there were 35 bridge collapses worldwide due to ship/barge collisions, and more than half of them occurred in the US.

I would suggest you follow the coverage on GCaptain.com, a website run by John Konrad, a man who's licensed to sail the biggest ships in the world and has done so. Konrad writes this morning:

Agencies are reporting the containership Dali, which collided with a Baltimore bridge on Tuesday, “lost propulsion” while exiting the port. The crew on board alerted Maryland officials that they had lost control of the vessel, as reported by ABC News, citing an unclassified U.S. intelligence report.

“The vessel notified the MD Department of Transportation (MDOT) that they had lost control and a collision with the bridge was possible,” ABC quoted the Cybersecurity and Infrastructure Security Agency’s report as saying. “The vessel struck the bridge, causing a complete collapse.”

He further writes:

Despite the quick restoration of lighting, this suggests a full blackout occurred, prompting the emergency generator to restore basic electrical services and lighting.

Without propulsion or tugboats, a ship this size is nearly impossible to stop.

The emergency generator does not connect to propulsion but should support steering and navigation systems but the ships heading appears to have been pushed off course by the wind directly into the support column.

Ships are not required to have tugboat escorts when passing under the Francis Scott Key Bridge so they have limited ability to slow down on their own when they lose power and can not put the propeller into reverse.

There was a belch of black smoke right before the collision. I've seen speculation that was caused by the pilot throwing the engines into full reverse as a last gasp attempt to slow the ship. I have no idea if that's true or not.

Among other sources, I watched the What's Going on in Shipping? early take. Looks like the Dali dropped its port anchor to try and effect/assist a turn. The engine powering back up could be what doomed the bridge, as it may be why the ship turned a bit more square at the pylon.

Hadn't thought about it, but one of the comments points it out: the rudder was almost certainly trying to turn to port, then the propulsion comes back online, but is reversed, so that port turn becomes a turn to starboard.