They are having a great time, rotating in place and emitting the sound a person makes when finally released from the illusions that get them through the day and seeing, with stunning clarity, the meaninglessness of life.
The video of these five metaphors for all of humanity was uploaded by YouTube user terrapinjoe some eight years ago. In the description, he claims he constructed the sailors, and concludes, “Hope you like em!!!” The fact that terrapinjoe has not uploaded a single video since then suggests the laughing sailors have imprisoned him, and are rotating in place somewhere right now, howling into the void.