I'd read a lot about submarines and seen them in WWII movies, but until I served with UDT-13 in Vietnam I'd never been aboard one. As a parachute and diving-qualified Photographer's Mate stationed with UDT-13, my official job was to document UDT operations in Vietnam. I also wanted to get some shots of the SDV (Swimmer Delivery Vehicle) underwater and also of life aboard a submarine. My real mission was to insure I shot enough photos for the cruise book LTJG Pete Upton and I were putting together. All the guys in the Team wanted one as a souvenir of their trip in country.
My first experience on board the USS TUNNY (LPSS-282) was to be led to the "UDT bunkroom." The guys in the Team were quartered up in the hangar. The USS TUNNY was an old fleet submarine that had been converted to firing the Regulus Missile and then back to an "SS" boat. In January 1969 she'd been converted back from an "SS" boat to an LPSS. Her sole purpose was to support UDT operations and insert commandos on special operations.
To get to the "bunkroom", you had to go down a hatch in the deck of the TUNNY, through the control room and up through a hatch in the crew's mess. The hangar was a big steel cylindrically-shaped tank with a huge, hydraulically operated door on the aft end. Two large hydraulic rams opened this door and, in the old days of the Regulus missile, the crew rolled a missile out onto the aft deck along tracks and set it up and fire it. Once the weapon had been launched, they'd roll the launcher back into the hangar, the sub would dive and everybody would live happily ever after - except maybe the guys downrange. The Regulus missile was never used in combat and was designed after the WWII German V-1 buzz bomb so fondly remembered by the civilian population of London.
The Regulus missile was relegated to the dust heap of outmoded military equipment, and the TUNNY, being not the latest and greatest example of our underseas technology, was assigned to support UDTs so they'd be able to use it as a shelter for SDV operations. LTJG Robbie Robertson was OIC of this UDT detachment.
UDTs used the SDV for clandestine beach recons. The SDV motored in submerged toward the beach with two swimmers and a driver. The driver would set it on the bottom in thirty feet of water and the two Frogs in the back seat would swim in toward the beach on a compass heading. They'd be attached to the SDV by a heavy fishing line wound on a huge fishing reel. The SDV driver would just let it reel out as they swam toward the beach, then reel them in as they started back. That was about the only part of the operation that was nearly free from Murphy.
One of the swimmers carried a little plexiglass tube containing a clock mechanism. One end was closed off with a fairly heavy latex material. As the depth changed, the rubber end would respond to the pressure change by being pushed in or out. A stylus connected to the rubber marked a roll of paper. The paper moved at a known rate, so it acted as a clock. The stylus made a black line on the paper that was representative of the gradient of the bottom. All the cartographers had to know was how deep the thing was when the swimmer turned it on, and they could extrapolate the depths from there. In spite of it being a primitive piece of gear, it worked quite well.
The TUNNY pointed her bow to sea, and we headed out of Da Nang Harbor. That night we steamed toward our area of operation. The sub, being conventional, was just a submersible surface ship, so it was more at home on the surface. We made our way offshore and, after dark, started creeping shoreward toward our objective.
At about three, or so, in the morning the sub dived. It was just like in the movies. I was sleeping in my bunk up in the hangar and the klaxon horn blew, Ahoogah! Ahoogah! followed by the command, "Dive, dive." I could hear the rumble of the diesel engines drop out quickly. The sub's main induction valve closed and my ears popped a little. In a few short moments the water was sloshing up under the hangar and then beside and over it. The gurgling passed by the steel side of the hangar past my head and then all became quiet as the sub completely submerged. It was an eerie feeling to hear that sound and feel the slight downward angle of the boat as she slipped quietly beneath the South China Sea. Now I knew what Captain Nemo felt like on board the NAUTILUS, safe and out of sight of the bad guys.
We needed to conduct SDV operations during daylight hours, but had to be in place to launch the mini-sub before the sun came up. The skipper of the TUNNY ran his boat toward shore until we were at a depth of around ninety feet. As the sub touched down on the seabed, I felt the slight jarring as we bounced along the bottom and finally came to rest. The submarine crew secured the electric propulsion motors and went to other tasks. By now the UDTs had crawled out of our racks and had our SCUBA gear ready for the day's work.
On this particular day, ace SDV driver QM2 Bill "Jake" Jakubowski would be at the controls. SN Bill Shearer and SN Steve Abney were to be the swimmers who'd ride in the back seat.
In the SDV, on top of the battery containers, was an array of aluminum 90 cu. ft. SCUBA bottles. These were the "boat air." On the way in to the beach and back out, the crew of the SDV breathed off these bottles. In spite of the telltale bubble trail left by these rigs, open circuit SCUBA was being used on these operations. Although classified at the time, our operations were not conducted north of the DMZ, and the topside Vietnamese were thought to be "friendly." Each man wore a set of double 90s on his back and the usual belt, KA-BAR, flare, and UDT life vest. They kept their Duck Feet stashed in the sub when not using them. On these operations the men wore, at the very least, a wet suit top. Although the water was warm, they would be in it for a long period of time.
All the support divers and SDV crew moved to the forward torpedo room. I would be locking out and working with the SDV deck crew for the SDV. RD3 "Mole" Roberts and I climbed up into the escape trunk and stood back to back in that very confined space. Neither one of us were little guys, and I want to tell you, it is no place for one who is clausty. We almost had to take turns inhaling. It was tight. Mole and I had to do a little dance so the submariners could get the lower hatch shut and then we were in total darkness. The first thing that happens is they start to flood the trunk. The water starts to rush in around your feet and quickly rises up to your chest. Just before it reaches your mouth, you yell out, "trunk's flooded, secure the flood", and shove your SCUBA regulator into your mouth, hoping you remembered to turn on the air before you donned the rig. The operator acknowledges by securing the flood valve leading to the trunk. Then he opens the air valve to pressurize the trunk to ambient sea pressure. I held pressure with my foot against the door leading out of the trunk. When the air pressure equaled the sea pressure outside, the door easily opened and I sounded off, "Door's open, secure the blow." I ducked down and swam out and up onto the deck of the submarine, and turned back to make sure Mole was right behind me.
I'd been diving since I was thirteen years old, but had never locked out of a submarine before.All the "real" UDT guys had done lockouts in training. It is an eerie feeling to swim along the deck of a submerged submarine and realize the only place you are safe is inside that gray, steel hulk laying on the bottom under you. Above you is the unknown and maybe death, but under you in that gray slab of U.S. Government issue steel is hot chow, a rack, a place to take showers (all we wanted, thanks to the TUNNY being the first submarine to have the Kleinschmidt vapor compression still installed as original equipment) and your buddies.
Mole and I swam aft along the deck toward the SDV where it was secured on deck behind the hangar. He was on my left and I was near the edge of the sub's deck. As we passed by the conning tower, I looked off to my right. There was a yellow sea snake swimming in formation with us about five feet away. I'd read about sea snakes and how they could kill you if they bit you and all that, but I'd never seen a live one. All of a sudden the damn thing pulled a ninety degree turn, and swam right for me. It came right at my face and bounced off my face mask. I was too scared to panic, so I just kept swimming. He turned and swam away. I guess he thought his reflection was either mating material or the enemy. I don't care. He went away.
Mole and I moved to the SDV and started loosening the chains holding it to the deck. The SCUBA tanks and the batteries in the SDV had been charged the night before. In a very few minutes two more guys locked out and swam up on deck beside us. We were only about fifty feet below the surface, so we had plenty of air in our tanks to do whatever we needed to do. When the crew had insured the SDV was ready to go, they gave a series of taps on the hull and Jake, Shearer, and Abney locked out. They wasted no time in getting to the craft and climbing in. Jake gave it a quick preflight check and nodded with a thumbs up. We released the chains and he flew the small submarine off the deck and into the hazy green gloom of early morning.
None of us had been outside the sub long enough to worry about decompression, so I locked back in with MM1 Harry Lapping, another guy on the deck crew. Mole locked in with the second member of the deck crew.
Chow on board a submarine is the best in the entire U.S. military. They have four meals a day, plus "soup down" in the afternoon when you can go by the galley and grab a bowl of soup and a sandwich. To us guys in UDT-13, that was hog heaven. We ate about all we could hold. They had steaks, ham, French fries, even ice cream.
LTJG Robbie Robertson and MM1 Harry Lapping(borrowed from UDT-21), and a couple more of us stationed ourselves up in the conning tower. The UQC (underwater communications unit) transceiver was there. The SDV trailed a thin, disposable wire behind it that was connected to the UQC on the TUNNY. The TUNNY had two way communication with Jake in the SDV - - for a while- - and then it went dead. Robbie kept messing with it and trying to raise Jake, but no luck, the wire must have broken. We all started grabbing quick glances at our watches as the time passed slowly by. Pretty soon we realized the boys would be out of boat air and have to go on SCUBA. This meant pretty soon the SDV would have to surface.
By now the sub was rolling gently back and forth, side to side in a ground swell. It got pretty quiet in the darkness of the dimly lit conning tower, and the serious expressions on everyone's faces added to the solemnness of the situation. There was no question that things were getting serious. The skipper ran up the periscope and we all took turns watching the surface toward the beach for signs of our little sub and three-man crew. Daylight was rapidly fading and the sky was overcast. The seas were getting rougher and nobody was talking who didn't have something important to say.
Finally, Robbie shouted. "There they are, I see a flare!"
He had just taken over the periscope when he spotted the SDV on the surface. Jake had a MK-13 Day/Night Distress flare burning hotly in his hand. The skipper surfaced TUNNY to decks awash and we rushed out on deck, pulled the small sub on board and chained it down. The SDV crew had run out of air and they were nearly exhausted and cold. We helped them get below to warmth and hot chow. The were happy to be home.
The mission was compromised, even though we got some good hydrographic data, and the after-action report showed some points needing improvement on future missions.
Thanks to these Vietnam missions, SDV operations nowadays have a whole new set of procedures, equipment, and missions. The attitudes of the men of UDT/SEAL Teams are the same now as then, and their spirit is universal within the U.S. Naval Special Warfare Community. They just don't make sailors any better than that.
NOTE: RD3 Walter "Mole" Roberts, of Burley, Idaho, was the last person ever to lock in aboard the USS TUNNY. He was number 3,860.
In June 1969 the LPSS TUNNY was decommissioned. On 19 June 1970 she was used as a target and sunk by a torpedo fired from the USS VALODOR (SS-490).