Original U.S. Vietnam War Era Operation Igloo White Seismic Sensor ADSID I with Fins U.S. Artillery The rotating firing pin still

The rotating firing pin still works correctly

The day the Army dropped the charges

hitting HMS Hood at least once and HMS Prince of Wales three times

showing the "laid lines" of pressed paper when held up to the light

Original U.S. Vietnam War Era Operation Igloo White Seismic Sensor ADSID I with Fins U.S. Artillery The rotating firing pin stillOriginal Item: Only One Available. Using the cover of darkness, dense jungle and bad weather, North Vietnamese trucks carried critical supplies down the Ho Chi Minh Trail nearly undetected. Since large numbers of American ground troops were not permitted into neutral Laos to stop the trucks, the U. S. Air Force deployed a system of electronic seismic sensor equipment to thwart the enemy's cover and alert U. S. commanders. This highly classified