Hamilton 308 Device Bomb Timer

May 2, 1972. A tremendous sound, like the booming of mortar fire, filled the skies over Hanoi. To the POWs standing in the yard at the Hanoi Hilton, the Viet Cong’s most notorious POW prison, the sound was unmistakable. It was the sound of freedom. The prisoners had sent a coded message to Washington, alerting their superiors of their plan to steal a boat and escape down the Red River to the Gulf of Tonkin. They hadn’t expected a response, but the sound that they’d heard—two SR-71 Blackbirds breaking the sound barrier low over Hanoi—was the U.S. Navy’s signal that their plan had been heard. More than that, it meant that they were going to be rescued, as Admiral Thomas H. Moorer (Chairman of the Joint Chiefs of Staff) authorized the U.S. Pacific Command to mobilize in an operation called Operation Thunderhead. However, the reality of what panned out under cover of night on June 3rd, 1972 resulted not in rescue, but in the death of a Navy SEAL, whose cause of death was not acknowledged by the US Government until 2008. The SEALs had been in Vietnam since 1962, where they acted as advisors for the commandos of the Army of the Republic of Vietnam. By the next year, they were being utilized by the CIA in covert operations. The fierceness and suddenness of their attacks against the Viet Cong—capturing key Viet Cong personnel or sympathizers—and their camouflage face paint gave them the nickname “men with green faces.” Ten years later, in late April 1972, SEAL Team One sailed from Subic Bay in the USS Grayback, an amphibious-transport submarine. The plan was to submerge the submarine and for two SEALs—Chief Petty Officer Philip L. “Moki” Martin and Lieutenant Melvin Spence Dry—to head for a island in the mouth of the Red River. There, they would lie in wait for the POW’s signal: a red light on a boat during the night and a red flag during the day. If they encountered the POWs, Martin and Dry were to intercept them and take them back to the Grayback. The plan’s success was contingent on many factors, not least of all stealth, as fishing boats and enemy patrolled boats traversed these waters. On June 3, 1972, the Grayback reached its position. Dry and Martin, along with two UDT-11 (Underwater Demolition Team 11) operators, launched from the Grayback in a Seal Delivery Vehicle (SDV) shortly after midnight. However, the strong current of the Red River—and navigational errors on the part of the SEALs—took them off course. Unable to locate the island which was to be their rendezvous point, the SEALs scuttled the SDV and started treading water. They were rescued several hours later, a few miles off the coast, by a search and rescue chopper assigned to the Helicopter Support Squadron (HC-7). The helicopter ferried them to the USS Long Beach, the operation’s command ship, where they debriefed and planned next steps. Ultimately it was decided to return the SEALs to the Grayback, where they could resume their mission. The helicopter was to drop them near the Grayback at 11 pm on June 5. For a focal point, they were to use the infrared signaling light—which revolved and flashed atop the Grayback’s snorkel mask. In briefing the pilots, Dry and Martin stressed that the drop should be made at 20 feet at an airspeed of 20 knots—20/20. In cloudy skies and in swells of four feet, Dry and Martin boarded the helicopter. But as the helicopter hovered over where the Grayback was supposed to be, the submarine was nowhere in sight. To compound matters, the mission’s secrecy meant that the helicopter flew in complete radio silence, with only two Navy officers being linked through the internal communications system, so Dry could not communicate directly with the pilot over the helo’s radio. After a few frantic passes—one which took the helicopter into North Vietnamese airspace—one of the Navy officers handed his helmet to Dry so that he could speak directly to the crew. He warned the pilot that the helo’s ground speed was far too high for Dry and Mar