The USS Grayback (SS-208) was a Gar-class World War II era submarine. The Gar-class boats were duplicates of the Tambor-class design. 1
The namesake of the Grayback is a lake herring, a small fish of great commercial importance in the Great Lakes.
The radio call sign of the Grayback was NAN-EASY-KING-FOX.
The Grayback, captained by Commander John A. Moore, sailed from Pearl Harbor on January 28, 1944, for her tenth and final patrol. She had received orders to patrol in the East China Sea. En route, she topped off her fuel at Midway Island. On February 8, she received orders to patrol the broad strait between Luzon and Formosa for eight days prior to taking station in the East China Sea. On February 25, ComSubPac transmitted a message to Grayback ordering her home. She was expected at Midway Island on March 7, 1944. She never arrived. On March 30, 1944, she was listed as missing and presumed lost with all hands. 2
Japanese records reviewed after the war indicated that on February 27, 1944, the Grayback torpedoed and sank the 4,905-ton cargo vessel Ceylon Maru at 31° 35′ N, 127° 47' E. Sometime after this attack, the Grayback was spotted surfaced by Nakajima B5N2 "Kates" of the Okinawa Naval Air Group. A direct hit was made on the submarine with a 250-kilo type bomb. The Grayback exploded and sank immediately at 25° 47′ N, 128° 45' E. Several Japanese antisubmarine vessels were summoned to the location and dropped depth charges over the spot where air bubbles were rising to the surface. Soon a lake of oil covered the surface measuring 100 meters wide and 250 meters long. If the Grayback received ComSubPac's last message and headed home immediately, she would have been at the approximate position reported in the Japanese attack. 3
Rick Cline wrote a compelling visualization of the Grayback's final moments.
Several hours later when it was all clear, she returned to the surface. A bright sun now lighted the sky overhead. Moore ordered a charge on their batteries as they fled the area at full speed. With her bow turned towards Midway, a triumphant Grayback was heading home. A Japanese plane suddenly appeared. Flying below the SD Radar beams, the Kate pilot had surprised Grayback. Lookouts sighted the intruder and Moore gave the order, "Clear the bridge! Dive, Dive!" As Grayback began to submerge in a crash-dive mode, two bombs exploded right next to them. Damage to the boat was serious if not critical. Water was pouring in at a dangerous pace. Crewmen frantically worked to stem the flow of seawater.
After his successful aerial attack, the eager Japanese pilot radioed for assistance. Nearby enemy destroyers steamed to the area as quickly as possible. Perhaps the same tin cans that were encountered when Commander Moore sank the Ceylon Maru earlier that day. With their boat seriously damaged, the crew of Grayback was fighting for their life and as a result, unable to run silent. Pinging for the submarine's underwater position, the destroyers easily located Grayback and began dropping depth charges. The sub was jolted by several devastating explosions, all extremely close. The depth charges proved fatal, rupturing Grayback's already damaged hull and they helplessly plunged to the bottom of the Pacific. Within a few minutes, fuel oil and debris bubbled to the surface, marking the final resting-place for the USS Grayback.
Eighty brave souls were lost that day - all forever entombed inside the submarine. The boat now rests somewhere on the bottom of the East China Sea. The exact location remains a mystery. 4
In his book, Cline cited three issues which might have contributed to the loss of the Grayback. First, in the report for her eighth war patrol, which ended at Midway Island on November 10, 1943, the captain of the Grayback reported problems with the range performance of her SD Radar.
3. RANGE PERFORMANCE - The range performance of the SD Radar was disappointing. Planes were picked up at from four to eight miles, often after being discovered by the lookouts. Land echoes, from high volcanic islands, were not received until the range had been closed to twelve miles. The range performance of the set prior to the installation of the whip type antenna had been excellent. It is believed that a mismatch exists in the present system, and a complete check of the equipment is planned on arrival at an advanced base. 5
Cline opined that if the range performance problem had not been fixed, it could have been a factor in the loss of the Grayback during her tenth war patrol. However, I believe it was very likely that this problem was taken care of at Pearl Harbor before the Grayback sailed on her final patrol.
The second and third issues are found in the report for Grayback's ninth war patrol, which ended at Pearl Harbor on January 4, 1944.
The SD Radar performance was highly satisfactory. Plane contacts were at from 8 to 18 miles. Planes contacted by lookouts were flying low, under the minimum performance altitude of the [SD Radar] equipment. Only one trouble was encountered. The blower motor in the transmitter failed, and the transmitter tubes burned up. 6
Cline wrote that the blower motor issue could have left the Grayback without the use of her SD Radar on February 27, 1944. The issue of the Japanese pilots flying beneath SD Radar field was not new. William Ruhe had experienced the same problem.
...the Dragon [USS Seadragon] had been fitted with an SD air-search radar that could pick up aircraft out to about twenty miles. But low flyers could get in undetected by flying beneath the upward beamed lobe of radiation. 7
It is impossible to know for sure if any of these issues played a role in the loss of the USS Grayback.
Edwin P. Hoyt, a prolific writer of books about World War II military history, wrote "The Grayback went out in January, heading west, and patrolled between Luzon and Formosa; she sank two steamers and then a big 10,000-ton tanker. Next day, she attacked another convoy and expended all her torpedoes sinking the Ceylon Maru in the East China Sea. But then a Japanese carrier plane found her on the surface, attacked and bombed, and the submarine exploded and sank immediately. Americans had traded eighty men for 21,000 tons of ships on that patrol, but the Grayback total record was much more impressive; a submarine, a light cruiser, and a destroyer had gone down to her torpedoes, so she had paid out well." 8
The official announcement that the Grayback was lost was made on June 20, 1944:
Navy Department Communiqué No. 526, June 20, 1944
1. The submarine, USS Grayback, is overdue from patrol and must be presumed to be lost.
2. The next of kin of casualties of the Grayback have been so notified.
A list of the submariners lost with Grayback is maintained at On Eternal Patrol.
The Grayback received eight battle stars for her World War II service. The submarine and crew received two Navy Unit Commendations for their seventh, eighth, ninth, and tenth war patrols. Her JANAC score is 63,835 tons sunk in fourteen enemy vessels. Her Alden-McDonald score is fifteen vessels sunk for 70,917 tons and eleven damaged for 50,331 tons. Her SORG score is eighteen and one-half vessels sunk for 98,900 tons and ten vessels damaged for 54,300 tons. 9
1. Alden, John D., The Fleet Submarine in the U. S. Navy: A Design and Construction HistoryUnited States Submarine Losses World War II, p. 74.
2. Blair, Clay Jr., Silent Victory: The U. S. Submarine War Against Japan, p. 589.
3. Roscoe, Theodore, United States Submarine Operations in World War II, p. 317; Grayback in Dictionary of American Naval Fighting Ships; Miller, Vernon J., "U. S. Submarine Losses," issue 43, p. 205; Hackett, Bob and Peter Cundall, "CHIHAYA MARU: Tabular Record of Movement," published online at Combined Fleet.
4. Cline, Rick, Submarine Grayback: The life & death of the WW II sub, USS Grayback, p. 217-218.
5. Submarine war patrol reports on CD, USS Grayback (SS-208), Report of War Patrol Number Eight, p. 46.
6. Ibid., USS Grayback (SS-208), Report of War Patrol Number Nine, p. 32.
7. Ruhe, William J., War in the Boats: My World War II Submarine Battles, p. 72.
8. Hoyt, Edwin P., The Destroyer Killer, p. 105-106.
9. Alden, John D., and Craig R. McDonald, United States and Allied Submarine Successes in the Pacific and Far East During World War II, Fourth Edition, see USS Grayback (SS-208), Attack Nos. 94, 95, 103, 387, 404, 414, 484, 485, 486, 487, 512, 666, 815, 816, 817, 824, 826, 827, 1197, 1208, 1226, 1238, 1239, 1416, 1417, 1418, 1419, 1424, 1425, 1426, 1427, 1443, 1656, 1657, 1685, 1686, 1687, 1695, 1696, and 1699; Submarine war patrol reports on CD, data collected by the Submarine Operations Research Group (SORG) in the report "Results of U. S. Submarine War Patrols Listed Alphabetically by Name of Submarine"; Japanese Naval And Merchant Shipping Losses During World War II By All Causes, Joint Army-Navy Assessment Committee, USS Grayback (SS-208).