Martin P4M-1 Mercator from below, 1961
Here we see the Martin P4M-1 Mercator from below in 1961. The P4M-1 was designed as a bomber, but only saw service as a long range reconnaissance aircraft. Its most unusual feature was its use of piston and jet engines, with the piston engines in the front of the nacelle and the jet engine in the rear. In this view we can just make out the air intake for the jets, just below the leading edge of the wing.