Did you see the Science Channel’s take on this?
They showed that giant methane bubbles released from the ocean floor could sink large ships and down airplanes. That was just one possible explanation.
I remember the old Leonard Nimoy’s In Search Of program on the Bermuda Triangle.
I always figured it was just the law of averages. A lot of traffic in the area, so you will have more accidents. Perhaps weather might play an important role.
The methane theory is interesting. Seems like it would be easy to verify. Just put sensors capable of detecting methane around the area.