The purpose of the Beaufort Wind Force Scale is to enable observers at sea to estimate the true wind speed by making observations of the effects of the wind on the sea. As an aid pictures are provided so that the observer can match what is seen with the picture in the book that most closely matches what is being seen.
Evidently many mariners believe that the ability to use a picture book guide for wind velocity is the epitome of seamanship.
Here's the captain of the El Yunque at the MBI.
Mr. Fawcett: I just want to ask you to restate something. You were asked a question about the ship’s anemometer and you made a comment. Can you take a moment to reflect on that comment and talk about the importance of the anemometer for shipboard operations?
WIT: The comment that I made was that I couldn’t think of anything less relevant than the anemometer to talk to Mike Davidson about.
CAPT Neubauer: Sir, can you just clarify if the anemometer is important to you as a Master on board the El Yunque.
WIT: No the anemometer is not important to me, it’s not a piece of required equipment. In fact, the assessment of weather and sea state and wind direction is done very well by looking out the window. You can also assess wind direction by looking at radar in terms of the direction that has the most sea clutter. And I would prefer ship’s officers to gain their information from there and then see if the anemometer is corresponding to that. That the reliance on a piece of digital data from a little wind propeller on top of the
weathervane on top of a mast that has air currents blowing all around it is not a gold standard on reliability of what’s happening with the wind. So I would prefer that to be used as a tool to verify. We do have an anemometer, it does work. I do not look to the anemometer to base a decision on what I’m going to do with the ship and the ship handling because that piece of equipment has a digital read out that says this. I do not think that the anemometer plays into my decisions on what’s going on with the vessel.
Don't need a little wind propeller when you have a picture book guide.
Mr. Fawcett: In his final message from the ship, the El Faro to shore, Captain Davidson made the statement that he’s experiencing, not quote the word experience, but he reported heavy winds. What are the velocity of heavy winds?
WIT: Heavy winds is not a technical term. I can’t give a definition for what he described as heavy winds.
The term "heavy winds' is too vague. Need a number.
MBI Mr. Fawcett takes the captain by the hand and leds him out to the bridge wing.
Mr. Fawcett: If you took me out on a bridge wing at night, how would I know the difference based on how you’re talking about observing the actual wind and radar clutter and so forth if the wind was blowing 70 knots or 105 knots?
WIT: I’ve not stood in 70 knot winds or 105 knot winds. I am not, I don’t have anything in my experience to tell you whether you’re standing in a 70 knot wind or 105 knot wind.I personally doubt that I would be standing in 105 knot wind.
Mr. Fawcett: Talking about the air currents around the mast where the anemometer is placed, using Bowditch, Knights Modern Seamanship or other tomes available to mariners, can you take the ship’s speed, the compared wind and convert it to true wind and true speed using the tools available on the bridge of a ship?
Mr. Fawcett: And that would then give you an accurate wind speed?
Estimating wind speed by observation is cadet level stuff, why is a captain taking pride in that skill?
These are the people that TOTE trusts 100% to avoid hurricanes, they think using a picture book to gauge wind velocity is the height of seamanship but need a computer to tell them the direction to the eye when it's just a few miles away.