A Shield and a Sword Intelligence Support to Communications with US POWs in Vietnam

A Shield and a Sword Intelligence Support to Communications with US POWs in Vietnam

Capt. Gordon I Peterson, USN (Ret.) and David C. Taylor

On 2 and 4 May 1972, two US Air Force SR-71 Blackbird recon­naissance aircraft overflew Hanoi, North Vietnam. A third aircraft stood back, ready to take the place of either plane if it was unable to perform its task. The pilots had not been told the objective of their unusual mission. At precisely noon on each day, flying at supersonic speed, the lead plane set off a sonic boom. Exactly 15 seconds later the second aircraft’s signature shock wave signaled to US prisoners of war (POWs) held captive in the Hoa Lo prison that their proposed escape plan had been authorized.

Earlier, in April, Adm. Thomas H. Moorer, chairman of the Joint Chiefs of Staff, signed a memoran­dum to the Commander in Chief of the US Pacific Command approving Operation Thunderhead, the code name assigned to the US Seventh Fleet’s POW rescue mission. The amphibious-transport submarine USS Grayback, with a platoon of Navy SEALs on board, was deployed off the coast of North Vietnam in June to rescue any POW who had managed to escape and reach a predetermined rendezvous point, a small island at the mouth of the Red River. The platoon was directed to establish an observation post on the island and keep watch. Given the operation’s military risks and political implica­tions, it is reasonable to assume that President Richard Nixon knew of and had authorized the operation.

How was it that the US military in Washington, DC, could know of, consider, and communicate approval of an escape plan the POWs them­selves had proposed? How did the Navy’s on-scene operational com­manders know the plan’s details in order to deploy suitable forces to identify and rescue escaping prison­ers at the correct location and time?

The answers to these questions rest in the innovative and coura­geous ways the POWs in the Hoa Lo prison—widely referred to as the Hanoi Hilton—communicated among themselves and then with the outside world. Communication with Washington involved the covert as­sistance of CIA, which worked with the Pentagon and other intelligence agencies to make possible a commu­nication channel maintained during the POWs’ prolonged confinement.

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Posted: Mar 29, 2016 07:17 PM
Last Updated: Mar 29, 2016 07:17 PM