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The question on everyone's mind: Why did El Faro set sail if a storm was coming?

Assessing risk on the seas is not straight-forward

Data available, but in the end, it is up to the captain

CNN  — 

To the layman, the most obvious question following the presumed sinking of the cargo ship El Faro is: “Why would a ship set sail knowing that a tropical storm was brewing nearby?”

The company that owns El Faro has its explanation – that the captain had a “sound plan,” but a malfunction left the ship without propulsion, disabled in the path of Hurricane Joaquin.

Others – inside and outside the marine industry – are raising questions about El Faro’s seaworthiness or pressure on the captain to deliver on time.

In the marine shipping business, bad weather is an ever-present risk. But when it comes to tropical cyclones, there are guidelines in place to help captains make decisions on their routes. In the end, mariners say, it is the captain who must take all the information available and make a decision.

The ’123 Rule’

According to James Staples, a cargo ship captain and maritime safety consultant, the rule of thumb is a decades-old guideline called the “1-2-3 Rule.” The numbers refer to the first, second and third day of a storm forecast – information that is essential to using the rule.

The guideline basically entails mariners staying a certain distance from a storm’s predicted path based on the National Hurricane’s forecast errors, and the radius of strong (34-knot) winds.

Adhering to the guideline used to mean a ship would stay at least 100 nautical miles from the projected path of a storm. That distance could be even greater depending on the predicted radius of gale-force winds.

As forecasting technology has become more precise, the 1-2-3 Rule has been modified to reduce those distances to some extent, but the basic idea is the same.

A diagram of the new 1-2-3 Rule.

One of the questions among mariners is whether El Faro’s captain followed the rule. It’s something that can’t be answered yet, given the limited details available.

However, rule or no rule, El Faro Capt. Michael Davidson is the one responsible for looking at the information and making a decision, Staples said.

“What you want to do is to conduct a recurring risk analysis for all possible scenarios,” Staples said. “You want to be going through that risk analysis all the time.”

Worst-case scenario

The owners of El Faro insist Davidson had a “sound plan that would have enabled him to clearly pass around the storm with a margin of comfort that was adequate in his professional opinion.”

A friend of the captain agrees with the assessment, describing Davidson as a capable and experienced mariner.

“My guess is that he saw that he could outrun the storm, providing everything went right,” Larry Legere, of Maine, said.

Legere, an experienced captain in his own right, told CNN’s “New Day” that he’s known Davidson since the 1970s, when Legere was a ferry captain and Davidson served as a deck hand.

“Mike was a very capable and experienced captain,” Legere said. “He would have weighed all of the factors – the weather, the condition of the ship.”

Legere said that deadlines to deliver cargo generally play into a captain’s decision to sail.

“However, I don’t believe he would have been pressured by the company, considering the weather forecast and so forth,” he said.

How much margin for error the captain left is unknown.

It was up to Davidson, as captain, to decide how close El Faro would get to the hurricane’s predicted path, said Fred Pickhardt, owner and chief marine meteorologist at Ocean Weather Services.

“How close you come comes down to the experience of the captain, and the crew,” he told CNN.

Regardless of any guidelines, “the most important thing is the captain’s experience, the seaworthiness of the ship, and the experience of the crew,” he said.

The biggest compounding factor, he said, might have been El Faro’s loss of propulsion.

A ship that can maneuver can probably survive a hurricane by sailing into the waves, Pickhardt said. But if the ship is disabled and getting pounded by waves on its broadside, it will become more unstable, he said.

Unpredictability

Tote officials said they trust the company’s captains to be the decision makers, and that up until El Faro lost its propulsion, the reports were not alarming.

The captain sent an email to headquarters September 30 saying he was aware of the “weather condition” – the increasingly powerful Hurricane Joaquin – and that he was monitoring its track, though conditions where the ship was “looked very favorable,” Greene said.

Even with improvements in modeling the paths of hurricanes, the errors of uncertainty are still significant, said Lee Chesneau, a marine meteorologist and professor who teaches mariners about the 1-2-3 Rule.

Hurricane Joaquin is one example of a storm that did follow the predicted path, and just getting caught in winds higher than 34 knots make it much more dangerous to divert, he said.

CNN’s Eliott C. McLaughlin contributed to this story.