Basic geometry comes to rescue of submarine

Geometry, as every high school student knows, is the study of points, angles and lines. After spending endless hours bisecting angles and dissecting theorems, geometry students complain, "What am I ever going to use this for?" For that plaintiff cry, Lt. Cmdr. Charles M. Cooke Jr. had a ready answer.

In September, 1920, the S-5 was one of the U.S. Navy's newest and largest submarines. The 231-foot vessel had just been delivered to the Navy, when Cooke sailed for the Delaware Capes to perform a "crash dive" in preparation for a submerged test run. At that time, submarines were powered by diesel engines while on the surface and switched to battery power when submerged. The main induction valve controlled the air supply to the diesel engines. This valve had to be closed before the vessel went under the surface otherwise water would be pumped into the ship. As the S-5 began to submerge, the critical valve was left open. Water flooded into the submarine, which settled to the bottom of the ocean near the mouth of the Delaware Bay.

The crew of the submerged vessel had no way of contacting the outside world, and the air supply aboard the S-5 would be exhausted long before anyone on the surface could locate the stricken submarine. Cooke coolly drew on his knowledge of geometry to devise a plan to save his crew. The S-5 was 231 feet long, and the water was 170 feet deep. It would take less than a 90-degree angle for the vessel to break the surface. Cooke shifted all of the water in the submarine forward, and the trapped air rushed to the stern of the vessel lifting the aft end of the S-5 off the ocean floor. As the stern rose, the water in each compartment rolled forward. After the S-5 stabilized at a steep angle, Cooke crawled into the tiller room in the stern of the boat. He could hear waves lapping against the side of the vessel. Careful tapping on the side enabled Cooke to determine that only about 17 feet of the ship was above water. If the sailors could cut through the hull of the submarine, they would all be saved.

A hand drill was used to cut a hole through the steel plates that formed the skin of the S-5. The tiny hole allowed a small but steady stream of fresh air to pour into the submarine. Using an electric drill, the sailors worked in shifts to enlarge the original hole. After several hours of drilling, four holes had been created. At this point, the remaining electrical power in the submarine failed.

The crew continued to attack the small opening with a hacksaw blade and the hand drill. Eighteen hours after the initial accident, the hole was large enough for Cooke to see a distant ship, but it failed to notice the slender stern of the submarine. The steamer SS Alanthus was nearly past the mouth of the Delaware when a lookout spotted what he thought was a buoy. The sailor alerted the captain, who changed course to investigate the uncharted buoy. When the Alanthus reached the "buoy" they discovered the stricken submarine. After another ship arrived, one of the hull plates of the S-5 was pried loose, and all the men aboard the submarine were saved. Attempts to salvage the S-5 failed, and the submarine remains beneath the ocean near the mouth of Delaware Bay.

The unruffled way that Cooke and his crew behaved under enormous pressure have become legendary in submarine lore. Had it not been for Cooke's knowledge of high school geometry, the men of the S-5 would have been buried in a watery grave off Cape Henlopen.