Martin JRM-1 Mars

Glenn L. Martin Company · USA · first flew 1945 · transport aircraft

The JRM-1 Mars was the first production variant of the Martin Mars, a massive four-engine flying boat that became the largest operational flying boat to serve with the US Navy.

Recognition (WEFT)

W — Wings	High-mounted, tapered
E — Engines	4 × piston, wing-mounted
F — Fuselage	35.7 m fuselage
T — Tail	Conventional

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Massive four-engine patrol flying boat
One of the largest piston flying boats ever built
High parasol wing above deep double-deck hull

Unmistakable due to sheer size — four large radial engines on a high parasol wing, deep double-deck hull, and a single fin distinguishes it from all contemporaries.

Specifications

The Martin JRM-1 Mars has a length of 35.7 m (117 ft).
It has a wingspan of 60.96 m (200 ft).
Its maximum speed is 338 km/h (210 mph).
Typical crew: 7.

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

History

Originally ordered as a patrol bomber in 1938, the XPB2M-1 prototype first flew in July 1942; the Navy shifted the requirement to cargo transport and ordered the JRM-1 production series. The first JRM-1, named Hawaii Mars, was delivered in 1945.

Variants

Five Mars boats were completed: the initial JRM-1 units were followed by the improved JRM-2 with Wright R-3350 engines and the final JRM-3 conversion; all survivors were eventually used as water bombers in Canada.

Where you'll see it

The Mars fleet served briefly with the US Navy's Naval Air Transport Service before being declared surplus; four aircraft were sold to Forest Industries Flying Tankers in British Columbia, where they fought wildfires as water bombers for decades.

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