One of the most infamous cases is that of the disappearance of Flight 19: on the 5th of December of 1945 five Avenger planes took off from the Florida Naval Base, never to return... "The Lost Patrol", as these planes are also known, have been extensively researched even by the Navy itself with the cause of the incident ultimately stated as unknown in the final report about the mission. But wait, there's more: later in that fateful December day, two Martin Mariner Planes (planes used in rescue missions that were capable of landing on water) were sent to locate and rescue the pilots of the Flight-19 mission; needless to say, they were unable to, but the mystery deepens even further as one of the planes also didn't return to the base. Some say this was caused by the phenomenon known as St. Elmo's fire, air filled with plasma (the same state of matter lightning is in) that appears as luminous globes of light, causing the plane's compass to go crazy and ultimately blowing up the plane, with the electrically-charged air being enough to light the fuel present on board; this sounds like a long shot, and even scientist doubt something like this could really happen, creating further confusion with regards to disappearances.
Aren't lost planes not enough to spook you out? What about a ghost ship? Yes, among the many mysteries of the Bermuda Triangle, there is at least one such case, and a very old one at that: the Mary Celeste was found without a single living person on board on December 4th of 1872 (starting to notice a pattern?), even though it sailed through calm weather and had a very able crew. Sometimes referred to as a cursed ship during its times because of the many accidents that happened to it, such as its first master mysteriously dying of illness (the ship was called "The Amazon" at the time) or colliding with another ship during its first crossing of the Atlantic. When the ship was acquired by an American called James Winchester, renovated and renamed, it sailed off for its first (and last) trip, having to pass through, you guessed it, the Bermuda Triangle (it departed from New York): it was directed to Genoa, Italy, carrying commercial alcohol. Found off the coast of Portugal by another ship (the Dei Gratia), as of today its mystery has not been solved yet, as possible explanations are not substantiated by facts, still being one of the greatest mysteries of the sea.