A Rare Insider’s Look at The Once Top Secret Navy SEAL Mini Sub, The Shadowy SDV.

ntil very recently it was difficult to even get a look at a SEAL mini-sub like the SDV. (All images: Author unless otherwise stated).

Freezing Cold, Pitch Black and Deep Underwater, Navy SEALs Used This Secret Mini-Sub for Classified Missions We Still Don’t know About.

It is cold, black and wet.

Two hours before moonrise, twenty feet below the sparkling, gloss black surface of a nighttime foreign ocean, six very cold men in black dry suits, LAR V Draeger rebreathers and so much combat equipment they can barely move, huddle inside a 22-foot long, flat black, metal tube as it chortles along quietly beneath the dark sea.

These six silent men were launched under concealment of darkness from the deck of a submerged Los Angeles class attack submarine ten miles off the coast of a classified foreign nation. Don’t bother Googling it. You’ll never find it.

Until very recently it was difficult to even get a look at a SEAL mini-sub like the SDV.

Now there is the near silent hum of the mini-sub’s electric motors. The rhythmic gurgling of the mini-sub’s internal SCUBA regulators the men are breathing from to save time on their bubble-less Draeger rebreathers. In the back compartment of the mini-sub, it is pitch black. Up front in the two-man cockpit, dim light glowing from navigation instruments is the only illumination.

The SDV we got a look at is from SEAL Delivery Vehicle Team 2 in Little Creek, Virginia.

The black mini-sub leaves a delicate, glistening bubble trail underwater as it moves slowly into shallower waters at about 4 knots. Once close to shore, at optimal tide, before the moon rises, the men will “park” their miniature submarine on the sandy bottom, switch from the internal SCUBA rigs to their tactical Draeger rebreathers, and leave the mini-sub for their short swim in toward the beach, counting their fin kicks to measure distance as they swim.

A rare look at the instruments inside a Mark 8 Mod 1 SDV.

The team arrives on shore without detection, six black, wraith-like figures invisible on the moonless coast as they move silently inland, the only sound the scurrying crabs they startle as they cross the beach toward a top-secret target we’ll never read about.

The cramped and uncomfortable rear passenger compartment of a Mark 8 Mod 1 SDV.

The U.S. Navy SEAL Delivery Vehicle or “SDV” is one of the most secretive and seldom seen assets in the entire special operations community. Because every mission it is used on is classified, and are hardly ever revealed to the public, the SDVs have remained mostly a mystery.

The main screw and guidance planes of the Mark 8 Mod 1 SDV.

At NAS Oceana we recently got a rare look at an SDV, and were given the opportunity to climb inside the once-top secret mini-sub to try to imagine what riding in one under 30-feet of cold, black water inside a completely flooded, blacked-out compartment must have been like.

Some limited specifications of the Mark 8 Mod 1 SDV and a display of SCUBA rigs used by, presumably, the SDV crews. Today more performance information about he Mark 8 Mod 1 SDV is available in the public domain since the sub is no longer as secretive as it recently was.

Built by the shadowy Columbia Group, the Mark 8 Mod 1 SDV miniature submarine is probably a terrifying idea to anyone who is even slightly claustrophobic or afraid of the ocean at night. It takes a special kind of person to ride inside a tightly packed, freezing cold, flooded, pitch black metal tube for up to three hours underwater.

The Mark 8 Mod 1 SDV has, of course, been used operationally. Where and when specifically, is more difficult to document reliably. According to one account that never made it to mainstream media, “In 2003, SEALs using SEAL Delivery swam ashore along the Somali coastline and emplaced covert surveillance cameras. Known as ‘cardinals’, the cameras were designed to watch likely target locations for wanted terrorists as al-Qaeda and its affiliates began to regroup in the country, however the cameras only took one image a day and captured very little.”

What may be even more interesting about seeing the Mark 8 Mod 1 SDV up close for the first time is what this media opportunity really means. If Naval Special Warfare is displaying these formerly top secret miniature submarines to the public for the first time, it means they already have something better. Although this is an interesting look at how Navy SEALs operate, the new miniature submarine they are certainly using is likely a much more interesting story that we’ll likely have to wait for.

An official U.S. Navy photo of a Mark 8 Mod 1 SDV being deployed from the launch deck of a Los Angeles class attack submarine in a training exercise during the daytime. Most operational SDV insertions take place at night. (Photo: U.S. Navy released)

About Tom Demerly
Tom Demerly is a feature writer, journalist, photographer and editorialist who has written articles that are published around the world on TheAviationist.com, TACAIRNET.com, Outside magazine, Business Insider, We Are The Mighty, The Dearborn Press & Guide, National Interest, Russia’s government media outlet Sputnik, and many other publications. Demerly studied journalism at Henry Ford College in Dearborn, Michigan. Tom Demerly served in an intelligence gathering unit as a member of the U.S. Army and Michigan National Guard. His military experience includes being Honor Graduate from the U.S. Army Infantry School at Ft. Benning, Georgia (Cycle C-6-1) and as a Scout Observer in a reconnaissance unit, Company “F”, 425th INF (RANGER/AIRBORNE), Long Range Surveillance Unit (LRSU). Demerly is an experienced parachutist, holds advanced SCUBA certifications, has climbed the highest mountains on three continents and visited all seven continents and has flown several types of light aircraft.