An Underwater Ice Station Zebra: Recovering a Secret Spy Satellite Capsule from 16,400 feet Below the Pacific Ocean

The Trieste II Deep Sea Vehicle I (DSV-1), the U.S. Navy's most advanced deep sea submersible at the time, surfaced about 350 miles north of the Hawaiian Islands in the pre-dawn hours of 26 April 1972 after having salvaged a mysterious item from 16,400 feet below the Pacific Ocean. Publicly known as a nondescript "data package" from the Scripps Institute of Oceanography, the object was actually part of a film capsule from an American photoreconnaissance satellite, codenamed HEXAGON. Before today's digital technology, photoreconnaissance satellites used film, which capsules ejected from the satellite returned to Earth. The capsules, called "buckets," reentered the Earth's atmosphere and deployed a parachute as they descended toward the primary reentry zone near the Hawaiian Islands. In the case of the first HEXAGON mission in the summer of 1971, the parachute broke off causing the bucket to crash into the ocean, sinking on impact. This release of CIA material includes photos of the capsule on the ocean floor, pictures of the Trieste II (DSV-1), documents, and an article explaining how the CIA and U.S. Navy undertook the deepest undersea salvage then attempted. We have also provided a link to the U.S. Naval Undersea Museum, where the Trieste II (DSV-1) is on permanent display.

View the OPA Press Release and Collection Booklet

View the Naval Undersea Museum website [external link disclaimer]

Download photos from the CIA Flickr stream [external link disclaimer]

View National Reconnaissance documents [external link disclaimer]

View Interview with CIA about Secret Sub Mission in 1972 [external link disclaimer]

CIA’s Underwater Space Mission Revealed: Recovering A Secret Spy Satellite Capsule From 16,400 Feet Below The Pacific Ocean

     Presented at The Smithsonian Air and Space Museum, Steven F. Udvar Hazy Center

Purchase the booklet from GPO  [external link disclaimer]

Document List (PDF Format)

Documents in this Collection

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Document Number: 50dde1d8993247d4d83923b2
PDF icon 1971-10-28a.pdf444.29 KB

Document Number: 50dde1d8993247d4d83923c2
PDF icon 1971-07-28.pdf154.68 KB

Document Number: 50dde1d8993247d4d83923b3
PDF icon 1971-09-17.pdf37.82 KB

Document Number: 50dde1d8993247d4d83923c3
PDF icon 1971-09-14.pdf286.7 KB

Document Number: 50dde1d8993247d4d83923b4
PDF icon 1972-07-28.pdf1.46 MB

Document Number: 50dde1d8993247d4d83923c4
PDF icon 1971-08-23.pdf53.3 KB

Document Number: 50dde1d8993247d4d83923b5
PDF icon 1971-07-27.pdf80.55 KB

Document Number: 50dde1d8993247d4d83923c5
PDF icon 1971-09-16.pdf59.04 KB

Document Number: 50dde1d8993247d4d83923b6
PDF icon 1972-01-31.pdf75.82 KB

Document Number: 50dde1d8993247d4d83923c6
PDF icon 1972-04-27.pdf119.05 KB

Document Number: 50dde1d8993247d4d83923b7
PDF icon 1972-01-12.pdf32.49 KB

Document Number: 50dde1d8993247d4d83923c7
PDF icon 1971-07-10.pdf434.24 KB

Document Number: 50dde1d8993247d4d83923b8
PDF icon 1972-02-14.pdf33.21 KB

Document Number: 50dde1d8993247d4d83923c8
PDF icon 1971-10-28.pdf102.67 KB

Document Number: 50dde1d7993247d4d83923a8
PDF icon 1972-02-02.pdf68.61 KB

Document Number: 50dde1d8993247d4d83923b9
PDF icon 1971-07-12.pdf189.03 KB

Document Number: 50dde1d8993247d4d83923c9
PDF icon 1971-12-10.pdf77.9 KB

Document Number: 50dde1d7993247d4d83923a9
PDF icon 1971-08-05.pdf292.39 KB

Document Number: 50dde1d8993247d4d83923ba
PDF icon 1971-08-04.pdf46.36 KB

Document Number: 50dde1d8993247d4d83923ca
PDF icon 1972-02-03.pdf37.61 KB