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Squalus: Terror at 243 Feet


Squalus at Portsmouth Naval Shipyard, Maine, 1938
Photograph courtesy U.S. National Archives
It was early morning on May 23, 1939. Thirty-three U.S. sailors sat trapped on the icy seafloor off the New Hampshire coast in 243 feet (74 meters) of water in a disabled, half-flooded submarine called Squalus. Wet, cold, and low on oxygen, they were keenly aware that nobody had ever survived such a predicament, and that 26 of their shipmates were likely dead.

Squalus had performed well during its initial sea trials. Eighteen test dives went smoothly, but the 19th was calamitous. A ventilation valve that should have been shut was opened, due to either mechanical or human error. As Squalus submerged, water gushed into the rear compartments, killing nearly half the crew and sinking the sub.

The survivors released a messenger buoy and smoke bombs and waited, hoping desperately that someone would see them. Almost five hours later, Squalus’s sister ship, Sculpin, arrived. Then the rescue ships came.

In the helpless sub, the surviving men were comfortable though cold. They were instructed to rest and conserve oxygen. The situation became more desperate as sea water mixed with battery acid in the forward battery compartment and slowly filled the compartment with deadly chlorine gas. While the crew was able to protect themselves by sealing off this compartment, some of them would later have to go through it to escape.

“Greatest Submarine Rescue in History”

On the surface the rescue team, led by Commander Charles “Swede” Momsen, decided to use the new McCann Rescue Chamber, which was designed to attach to a disabled sub’s hatch and ferry survivors to the surface.

A diver descended to one of Squalus’ escape hatches and attached a cable that would guide the bell up and down. The men banged ecstatically on the hull upon hearing the diver.

During four trips to the sub all the survivors were evacuated, but not before rescuers dealt with a range of hair-raising and potentially fatal setbacks, including a tangled guide cable. A fifth trip in the chamber confirmed that there were no survivors in the flooded compartments.

The first rescue of its kind, the Squalus incident was later called the “greatest submarine rescue in history” by author Peter Maas.

After the rescue an equally impressive and successful effort was launched to raise Squalus and tow it back to port. The sub was eventually overhauled and recommissioned as Sailfish and served safely throughout World War II.

Despite being given their choice of duty, the survivors decided unanimously to continue to serve in submarines.

Next: Tragedy of Kursk >>



Crew Photo

Crew Photo

Squalus at Sea

Squalus Salvage

Momsen: Savior of Squalus

Charles “Swede” Momsen, who began his career as a submariner and rose to the rank of vice admiral, was haunted by the hundreds of men who had died aboard submarines, some of whom were known to have lived trapped for days because the U.S. Navy had no means of rescue.

Momsen first became famous as the inventor of the Momsen Lung, a breathing device that allowed submariners to escape from subs disabled as far as 200 feet (61 meters) down. Then he fought for years to bring his idea for a rescue diving bell to life despite resistance from the Navy.

With the success of Squalus rescue, Momsen’s efforts were gloriously vindicated.