By Nathan Pfau, Army Flier Staff WriterAugust 17, 2017
FORT RUCKER, Ala. -- As if it was pulled out of a scene from a James Bond movie complete with covert ops and spy planes, one Army Aviation aircraft played a vital role as the eyes and ears over the skies of Vietnam.
The Lockheed AP-2E Neptune sits on the western lawn of the U.S. Army Aviation Museum and is one of the largest aircraft in the collection. It served as a signals intelligence aircraft during the Vietnam War, and although it wasn't the first signals intelligence aircraft to fly during the war, it provided greater capabilities than its predecessors, according to Bob Mitchell, U.S. Army Aviation Museum curator.
"Back during the Vietnam War, the Army Security Agency basically ran an operation where they were using U-8 [Seminole} aircraft to monitor low-power radio transmissions and other signals -- it was a very covert program," he said. "This program was designed to listen for communications in the field to determine what the enemy was doing and be able to monitor that without them knowing it."
The program was successful in that the Army was able to intercept transmissions and information, but the capability of the U-8 and other aircraft were limited by their size and weight limits, and the Army quickly realized that a larger aircraft was needed, said Mitchell.
"When the mission first started out, they didn't have a lot of equipment or a lot of capability, so they had a small aircraft. As they got more involved with the mission, they realized that they needed more monitoring devices, better devices and more powerful devices," he said.
Since the Army didn't have a large, fixed-wing aircraft of its own, it eventually turned to the Navy, which had been operating P-2 Neptunes for some time as long-range, anti-submarine patrol aircraft.
In 1966, it was decided that the Navy would give the Army 12 P-2s that would be retrofitted to fit the Army's needs, and they were designated AP-2 Neptunes in the Army inventory.
"Since it was a covert program, the Army didn't want anyone to know that this aircraft was doing anything special, so they called it an AP-2 Neptune and not an RP-2, which would denote reconnaissance or security," said the curator. "The only external clues to the role of the aircraft were extended wing tips tanks to house the sensors, extra antenna and a solid nose, of which the original aircraft had a glass nose."
The plane was also kept painted in the Navy colors and proved to be a very effective surveillance system, able to house much more surveillance equipment, radios and monitoring devices, as well as a crew of up to 15, including pilots and ASA agents.
The program ran from 1965 to 1972, but as the Vietnam War began to wind down and the mission was no longer required, the Army returned the aircraft to the Navy, but the Navy allowed the Army to keep one, which now sits on the lawn of the U.S. Army Aviation Museum.