Music cruises have been around for years, now, and my pals and Day colleagues  Kristy Dorsey and Joyce Conlon have in fact set sail on such voyages. Yo ho ho and a B minor 7 and all of that.

I also have pals — Fred LeBlanc and John Thomas Griffith of Cowboy Mouth and Jim Suhler of George Thorogood and the Destroyers — who have played on these cruises. Reports are that it’s possible the musicians have more fun than the fans.

Here’s another thing about music cruises. None of these cruises ever seem to be the ones where 80 percent of the ship gets some odd tropical virus.

The answer is simple, in my opinion: it’s because, from the moment they wave bon voyage, folks on these ships are completely drunk for the duration. There isn’t a virus or plague that’s yet evolved that can compete with that sort of 100-proof Maginot Line.

But here’s something I’ve never seen before in the context of a music cruise, and I must say it gives me pause. Typically, the musical motif for one of these excursions has been good time classic rock, roots, blues and country — the sort of broad-appeal music that encourages good times and a slightly older audience demographic that implies not just a certain financial stability but also a small level of behavioral maturity.

Setting sail from Miami on December 7, though, is the First Annual Mayhem Festival Cruise.

Because nothing says “Catch some rays and cool waves and have a few tropical drinks” like a band lineup that includes Anthrax, Hatebreed, Lamb of God, Machine Head, Suicide Silence and Kingdom of Sorrow.

A trash/death metal cruise!

I didn’t know any of these musicians — or their fans — had ever seen the sun, much less lounged on a beach or a cruise ship promenade. I thought they all slept in coffins.

Have you ever seen the folks that go to shows featuring these artists? Not exactly Gilligan and the cast of The Love Boat.

How’d you like to be the cute restaurant hostess, working on her winter break from Florida State, who has to seat the passengers who’ve just been up all night, snorting roach paste in celebration of Lamb of God’s epic performance of "Blood Junkie," and who now stinkily demand their breakfast omelettes cut with meth?

And does the cruise line suspend the traditional black-tie dinner with the Captain?

For the love of God, I hope so. The only way to navigate a black-tie dinner with Hatebreed sitting at the head table is to hope Ahab is the captain. Otherwise … it becomes unspeakable.

Next up? A prog rock cruise? Yes, I’m a big fan of the form — but even I would be suspcious about a five-day cruise that only has time for one Keith Emerson solo.