Thread by @johnkonrad

The real mystery with the Mexican Navy tall ship ARM Cuauhtémoc isn’t what went wrong, we know the engine was likely stuck in reverse.

It’s why the tugboat wasn’t tied up.

I spoke with a New York Harbor pilot and a tug captain near the scene.

Here’s what we know 🧵👇

https://twitter.com/johnkonrad/status/1923947432947118436

This is important because the ship only has a small 1,125 horespower Auxiliary engine installed.

The Tugboat Charles D. McAllister is 58 years old but was repowered in 2007 with two CAT 3512 engines with 2,800 horespower.

mcallistertowing.com/our-fleet/char…

The tugboat should have been able to overpower Cuauhtémoc’s engine—even with wind and current pulling the tall ship under the bridge.

The problem?

It wasn’t tied up.

Without a line, the tug could only push across the current not pull the ship against it. Huge difference.

Here's the track of the ship as she left South Street Seaport

https://x.com/mercoglianos/status/1923924941377777970

Small ship engines are much less powerful in reverse.

If the tall ship had backed into the dock she could have easily powered out into the river and turned with no help from the tugboat.

But tall ships prefer to dock at South Street with their bow pointing inland. Why?

Because the photographers are on the shore and nobody wants photos of the ships stern against the Brooklyn Bridge

To leave the dock, Cuauhtémoc had to back into the current.

If she reversed straight out, her stern would’ve swung too fast—risking the bowsprit sweeping dangerously over the dock.

So the tug was positioned on the starboard quarter to push the stern into the current, giving her a controlled pivot.

You can see that clearly in this photo

Now if they had two tugboats they could have held the ship perpendicular to the current but they only had one.

The tugboat was not tied off. You can see in subsequent photos the tugboat sliding forward

At this point some mariners have suggested they drop the anchor.

You never want to crash into the shore (or a bridge) without trying the anchor.

Problem is the current plus wind plus engine in reverse probably would have overpowered the anchor

Anchors alone don’t stop a ship.

It’s the weight of the chain on the seabed that does most of the work and Cuauhtémoc didn’t have room to lay out much chain.

Dropping anchor might’ve helped her swing into the current and slow down…

But it wouldn’t have stopped her.

Strike one: Cuauhtémoc had to back out into a strong current.

Strike two: The engine failed—stuck in reverse.

Strike three: The tugboat wasn’t tied off, so it could only push, not pull.

Now we have to talk about the pilot.

By law, ships must take a local harbor pilot on board an experienced mariner who directs the vessel and coordinates directly with tugboats.

As we can see from this photo she is flying the Hotel flag which means she had a pilot aboard.

https://x.com/mercoglianos/status/1923968084605386874

New York is unique. State pilots bring ships through the harbor entrance—then hand off to docking pilots to maneuver upriver.

But here’s the catch: docking pilots operate under looser rules. And there are exemptions for warships and tall ships like Cuauhtémoc.

That matters.

The state pilots in New York - in this case the Sandy Hook Pilot Association - don't have the same level of river and docking experince as docking pilots.

sandyhookpilots.com

Cuauhtémoc was departing last night for Iceland, so it’s likely a Sandy Hook Pilot was aboard that would explain the hotel flag.

What we don’t know is whether a docking pilot was on board.

A docking pilot might have insisted the tugboat tie up, rather than push without a line connecting them.

southstreetseaportmuseum.org/cuauhtemoc/

There are also questions about the tug itself.

Charles D. McAllister is a 58-year-old tug with traditional flanking rudders—less agile and less powerful.

McAllister’s newer tugs use tractor drives. They’re far more maneuverable and can instantly thrust in any direction.

We don't know for sure, the more powerful and capable the tugboat the higher the cost to rent it.

If Cuauhtémoc had backed into the dock.
If a docking pilot had been aboard.
If the engine had shifted cleanly from reverse to ahead.
If two tugboats had been ordered instead of one.
OR if the tug had been tied off, not just pushing.

This incident likely never would have happened.

But nearly all maritime accidents and failures occur in complex systems by illustrating how multiple layers of defense, each with vulnerabilities, can align to allow a hazard to pass through. This is what investigators call the Swiss cheese model.

That said the Swiss cheese model also saved lives.

Why weren’t the midshipmen called down from the topmast?

Because if they’d all unbuckled to descend, more might’ve fallen.

Why didn’t the mainmast collapse?

Because it wasn’t wood—it was steel.

Why didn’t the bridge fall like in Baltimore?

Because Cuauhtémoc is much lighter than a cargo ship and the Brooklyn Bridge was built to survive a hit.

x.com/MattDursh/stat…

It’s absolutely tragic that two young sailors have lost their lives, and others remain in critical condition.

But the swift response from nearby McAllister tugs, FDNY fireboats, and NYPD securing the bridge undoubtedly saved many more lives last night.

“The sea is selective, slow at recognition of effort and aptitude but fast in the sinking of the unfit.” — Felix Riesenberg

For those lost, we must remember: the sea is unforgiving, and small mistakes compound fast.

That’s why navies still send sailors to sea on training ships like Cuauhtémoc—despite the risks.

Because a nation whose sailors forget Reissenberg’s lesson doesn’t just lose ships.

It loses wars and sovereignty.

And to the sailors who crossed their final bar today, we say

Eternal Father, strong to save,
Whose arm hath bound the restless wave,
Who bidd'st the mighty ocean deep
Its own appointed limits keep,
O hear us when we cry to thee
For those in peril on the sea!