Martin P4M-1 Mercator

Glenn L. Martin Company · United States · first flew 1946 · transport aircraft

The Martin P4M-1 Mercator is a unique long-range maritime patrol aircraft powered by a combined piston-and-jet powerplant, with each of its four nacelles housing both a Wright R-4360 radial piston engine and a Allison J33 turbojet for sprint capability. Only 19 were built.

Recognition (WEFT)

W — WingsLow-mounted, tapered
E — Engines4 × piston, wing-mounted
F — Fuselage25.6 m fuselage
T — TailConventional

WEFT is AircraftIQ's four-point recognition method — how it works.

Spot it by:

A sleek low-wing four-engine monoplane with a conventional tail; the mixed powerplant is not visible externally — the four nacelles appear to house standard radial engines with jet exhaust pipes.

Specifications

Figures are for the representative variant described above; marks differ. See how AircraftIQ sources figures.

History

Designed in the mid-1940s to provide the US Navy with a high-speed long-range patrol aircraft, the Mercator's unusual mixed powerplant gave it a significant speed advantage over pure-piston types. In service, the P4M-1 was primarily used for electronic intelligence gathering (SIGINT) along Soviet and Chinese coasts, a role that exposed its crews to considerable risk.

Variants

The P4M-1Q was the ELINT-configured variant used for electronic intelligence missions; this was the primary operational form of the type.

Where you'll see it

Served with US Navy patrol and VQ (electronic reconnaissance) squadrons from 1950; several were intercepted and one shot down by Chinese MiGs over international waters in 1956.

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