So, there was this TV show the other day about flight 19, the Navy Avengers that disappeared on a training mission in the Bermuda Triangle during WWII. Browsing the internet turned up this, which says that the Bermuda Triangle is one of two places on earth where true north and magnetic north are the same.
Now that's a questionable proposition from a questionable source, but, then, there's this from the University of California Santa Barbara, a west coast institution of higher learning and, therefore, above reproach:
http://scienceline.ucsb.edu/getkey.php?key=1051
Apparently, the other such place is the Dragon's Triangle in the Pacific Ocean, perhaps where Amelia Earhart disappeared. Ol' Fred Noonan had a habit of determining position by course and time converted to direction and distance, so factoring in a magnetic declination where there was none might have gotten him lost.
At the Miami airport, the current declination is -6.72 degrees, in Hamilton, Bermuda, it's -14.68 degrees, and in San Juan, it's +3.99 degrees. Going from negative to positive west to east and north to south, declination could conceivably be zero at some point or group of points, but general equality of true and magnetic north over the whole region does not seem right.
I wonder where if anywhere this proposition is true.
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It will be zero along the great circle that passes through the magnetic pole and the geodetic pole, the problem with that is the magnetic pole is shifting so that circle swings with the shift.?ÿ And the shift is accelerating.?ÿ
The line is called the agonic and this month for the first time in more than 300 years it passes through the observatory at Greenwich. Here's an article from Popular Mechanics:?ÿ
https://www.popularmechanics.com/science/environment/a28873196/true-magnetic-north/
That's a long way from the Bermuda Triangle!
Here, I guess, is the definitive word from NOAA:
?ÿ https://maps.ngdc.noaa.gov/viewers/historical_declination/
Kinda neat moving the slider to 1804 when Lewis and Clark began their journey and the 1940s when flight 19 was lost or maybe the 1700s when Europeans were losing gold to storms in the Atlantic.
But UCSB needs to update their page. Things have changed and are continuing to change. Wouldn't want some west-coast academic to get lost in the Bermuda Triangle!
When I was an aviator we used magnetic north in the airplane.
I think Flight 19 got lost, ran out of fuel, and crashed into the big ocean. Nothing all that mysterious about it. Navigating over the ocean before modern technology was not simple. I got disoriented a few times, your wrong perceptions are very powerful. Weird how you can be convinced you are going southwest when you are really going southeast, the compass must be wrong, I'm serious about this. I was over clouds so no clues on the ground. The controller sarcastically asked me if I was still going to Fresno and that kind of shook me out of it. Very strange feeling.
I get confused in two dimensions sometimes; three must really cause problems.?ÿ
The last CEO I served, now deceased, was a navigator on a bomber in the Pacific during WWII. I once asked him about his techniques and he told me that he looked for islands to match up with his maps. He said that guys who used sophisticated techniques got lost.
Time was short so I got no more detail than that. I guess he had a technique to use when islands weren't visible, but I don't know what it was.
Dead reckoning. Fly a heading and ground speed calculated from forecast wind velocity and direction for a calculated amount of time. I have a mechanical calculator that is used to do this but you can use trigonometry to break down the triangles too.
this is backed up by pilotage, that is identifying features on the ground. I was taught to verify a town, for example, by additional clues like the position of its airport or anything obvious shown on the chart such as radio towers.
this is what flight 19 was training on. The leader said his compasses were malfunctioning and he became convinced he was over the Florida keys but he was actually pretty close to where he was supposed to be. Some mistakes on identifying islands led him to eventually turn out to sea. A couple of the student pilots with him asked why they didn't simply turn to 270 and fly to the Florida coast but Taylor didn't think he was east of Florida. 270 was the standard instruction if you get lost. Why didn't they just leave the formation and fly west? Military discipline, mutiny is bad.
