Submarine Image Gallery
Submarine Image Gallery

The photonic mast, seen here in testing, is one of the revolutionary design changes incorporated into a new type of U.S. submarine. See our collection of submarine pictures.

Photo courtesy Naval Sea Systems Command

Crews onboard a submarine can spend months at sea, submerged, with no way to catch even a single glimpse of sunlight -- the only window to the outside world is the eyepiece of the periscope in the control room. The periscope is a fundamental piece of submarine equipment, and provides valuable visual data during battle and in determining the ship's position.

Despite its valued service for more than 80 years, the U.S. Navy will soon say "so long" to the conventional periscope. In 1999, construction began on a new breed of attack submarines that won't have a periscope. Instead, these new Virginia-class submarines will use non-penetrating imaging devices called photonics masts to perform surveillance tasks. Each new submarine will be equipped with two photonics masts, which are basically arrays of high-resolution cameras that capture and send visual images to flat-panel displays in the control room.

In this edition of How Stuff Will Work, you will learn the basics of a conventional periscope and how photonics masts will revolutionize the way submarines see the world around them.