During WWII, putting troops into battlefield areas by air meant either parachuting them in or using gliders. Both approaches had drawbacks; vehicles and heavy equipment could not be parachuted, and gliders could not take off under their own power and then return quickly with another load. This spurred the development of the assault transport, an aircraft that could operate from austere fields close to the front lines while being able to quickly load/offload cargoes.
Ruggedness and STOL capability were required, and these needs were seemingly met by a military outgrowth of Northrop's N-25 Pioneer. This heavy "bush" aircraft looked almost like a second generation Ford Trimotor, with three R-1820s, a high mounted wing, and fixed landing gear. The military C-125A (13 built) assault version could carry 32 troops or 11,000 pounds of cargo, while the C-125B was fitted out for search and rescue work in the far north. Very little use was made of either variant, as Fairchild''s C-123 Provider proved superior in the transport role, while helicopters proved better at rescuing downed pilots.
Bibliography: Photo of Pioneer NX8500H, 3-view Aviation March 1947 p.87
Robert McLarren "Northrop C-125 Based in Pioneer" Aviation Week November 8, 1948 p.21-22+
Gerry Manning 1,000 Preserved Aircraft in Colour P.93: YC-125A XB-GEY at Pima Museum
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