THE FALL AND RISE OF THE U.S.S. SQUALUS The Sinking May 23, 1939 7:30 a.m. On May 23, 1939 (7: 30 a.m.), under the command of Lieutenant Lover Naquin, the U.S.S. Squalus departs the Portsmouth Navy Yard, located along the Piscataqua River in New Hampshire, for its 19th test dive. On board are 59 men: five officers, 51 enlisted men and three civilian inspectors. The point of the day is to complete an emergency dive while cruising at 16 knots, diving to 50 feet within 60 seconds. At 8:35 a.m., Radioman Powell taps out his second communication to Portsmouth that the sub is diving, and that they will be submerged for one hour. After Portsmouth immediately acknowledges, Powell signs off and starts retracting his antenna. Naquin orders the crew to prepare to dive. Before nuclear power, submarines were propelled by diesel engines on the surface and electric motors underwater. It was not possible to use diesel engines underwater because they required air for combustion and spewed out toxic fumes. While on the surface, outside air was brought into the submarine through a main induction pipe, which fed into the diesel engines. A set of pipes circulated air in the submarine. When the vessel submerges, the induction valve slides over the air intakes to seal them from outside water. As a safety backup prior to diving, engine room valves could be manually shut. During emergency dives, it was general practice not to individually close the valves because it was time-consuming to do so. The dive was orchestrated from the control room by Lt. William T. Doyle. Here, he was able to follow the process of sealing the boat from the water outside by following the control board, which is commonly referred to as the Christmas tree. The Christmas tree consists of red and green lights, showing whether or not the valves are closed (red lights indicated open valves, green lights indicated closed valves). Seeing the green lights lit, the skipper then orders the dive to begin. As the boat passes an ocean depth of 50 feet, the call comes in that the forward and after engine rooms are flooding, with seawater making its way into the submarine through an unsealed induction valve that fed into the diesel engines. Upon notification of the engine rooms flooding, the diving officer and crew in the control room check to ensure all the lights on the Christmas tree are green. They were. Skipper Naquin orders the ballast tanks blown (filled with pressurized air) to surface the vessel. However, the added weight of seawater in the after compartments counter the lightening of the submarine, causing the sub to lunge upward at an angle. The rise toward the surface is short-lived, and the boat quickly sinks to the ocean bottom. Rescue of the Crew May 24, 1939 - 7:30 p.m. Charles “Swede” Momsen, two doctors and a diver leave from the Anacostia Naval Air Station in Washington, DC, in a seaplane and land at Portsmouth. After transferring to a Coast Guard cutter, they arrive. Navy divers and salvage ships responded quickly, and begin operations to rescue the surviving 33 crew members from the forward sections of the ship. After studying the situation, Momsen learns that there are 33 survivors in an atmosphere about twice normal pressure. Momsen figures there are three options to save the men: 1) Rescuers could pump out the flooded compartments to bring the Squalus to the surface, however, it’s very risky, since the reason for the sinking is still not known. 2) Have the men come to the surface using their Momsen Lungs (the submarine escape breathing apparatus he devised and which earned him the Distinguished Service Medal). Their depth was somewhat greater than the 207 feet for which the Lung had been tested. However, the men were very cold and undoubtedly weak from the foul air and tension. 3) The use of the diving bell, the newly developed McCann rescue chamber, a revised version of the diving bell Momsen designed. Momsen recommends the use of the diving bell, Admiral Cole concurrs. 11:30 a.m. The USS Falcon lowers the newly developed McCann rescue chamber, and over the next 13 hours, the 33 survivors were rescued. The Recovery of the Squalus Raising the Squalus would help to determine what caused the sinking, which was important since more submarines of the same type were being built. This would also enable repairs and outfitting that could save this valuable submarine. However, the challenge of getting the 1,450-ton, 310-foot-long vessel from 15 miles out at sea and a depth of 243 feet were unprecedented. The valve that caused the flooding could not be closed, so the entire submarine could not be pumped out. Rather, it would be necessary to fasten pontoons to the Squalus and blow out the fuel and ballast tanks. The recovery proceeded in three stages: raising the vessel 80 feet and towing it a mile and a half until it grounded again, raising the Squalus another 80 feet and towing it five miles to ground it in a region with a solid sandy bottom, and finally, raising it until it was no more than 40 feet deep. The last move would permit the submarine to be towed up the Piscataqua River at high tide to the Portsmouth Navy Yard. On September 13, the Squalus was raised, overhauled, and returned to active service. Due to the tragic deaths of 26 sailors on board, the decision was made to change her name. Recommissioned as the Sailfish, but the same hull number as the Squalus – SS-192 – the sub went on to be known by her crews as the “Squalfish” and was originally thought to be an “unlucky boat.” Though thought of as unlucky, the Squalfish went on to serve with great distinction during World War II. The boat was formally decommissioned on 15 November, renamed Sailfish on 9 February 1940, and recommissioned on 15 May 1940. Source: http://www.onr.navy.mil