SF book where plane captured in Bermuda Triangle

Question

I am searching for book from the late 70s (or thereabouts).

The details which I remember are:

• A passenger jet is snared while flying through the Bermuda Triangle and the passengers are enslaved by alien/other dimensional humanoids who attempt to control them using handheld pain boxes that emit rays.
• I believe the title began with "Z" and referred to the alien land where the passengers are taken.
• The title of the book is not Millenium.
• If I remember correctly, the aliens were bald and physically frail.

What is the name of this book?

Answer 1

The book is Zandra by William Rostler, first printed in 1978. Here's the Google Books reprint of an old SF&F Review:

"Zandra by William Rotsler, Doubleday, 1978, ISBN: 0385131437

This is the first book in a series of adventures set on the planet Zandra, second planet of a sun called Za. Zandra is peopled by both humans and aliens with assorted colorful tribes scattered across the planet’s surface and throughout the book. Quickly paced and smoothly written, the book opens with a commercial airliner on Earth vanishing over the Devil’s Triangle. The passengers are drawn through a dimensional warp to Zandra where they are quickly sold into slavery by alien captors. Ex-soldier Mace Wilde leads the group through a series of planned escapes with the help of policewoman Eve Clayton, actress Liberty Crockett, and animal tamer Barney Boone. Light fantasy which will appeal to fans of Lin Carter, Alan Burt Akers, and John Norman.--Dennis Maloney"

Review copyright: Science Fiction & Fantasy Book Review, Vol 1. No. 4. May 1979

How I finally identified the book:

After several days of fruitless, brute force searches that mostly gave me New Age and alien conspiracy titles, I found the book by Google searching: "science fiction "novel" Bermuda Triangle 1978" with the hope that a copyright notice would narrow the results, and it worked, though the answer was many pages down in the results list. I had run the same search string quoted above, substituting sequential years for the decade in which I thought the book was published to get the correct result. Of further note, "novel" was set off by quotes to further filter results, a Boolean command that remains effective even with one word.

Thanks to those who made suggestions to help me identify this book.

Answer 2

Sargasso by Edwin Corley? My boyfriend was reading it the other day and it sounds like it.

The action is set in the Bermuda Triangle and the "s" is close in sound to "z".

Not matching as well is that the plot of the book follows Paul Forsythe, an ocean surveyor and captain of the ship Lamprey, as he looks into the disappearance of three astronauts, so no passenger jet involved.