Since 1943 the Lockheed Constellation had been in USAAF service as the C-69. The use of the Constellation by the USN for patrol and airborne early warning duties was first investigated in 1949, when the USN acquired 2 Lockheed L-749 Constellations. First flown on 9 June 1949, the PO-1W carried large, long-range radars in massive radomes above and below the fuselage. As the radomes possessed considerably more side area, the vertical stabilizers of the PO-1W had to be enlarged. After the PO-1W (redesignated WV-1 in 1952) had proved that it was possible to operate large radars on aircraft, the USN ordered the WV-2 based on the L-1049 Super Constellation. The WV-1s were transferred to the Federal Aviation Agency in 1958–1959.