Stinson L-5 Sentinel
The Stinson L-5 Sentinel was a World War II era liaison aircraft used by all branches of the U.S. military and by the British Royal Air Force. Along with the Stinson L-1 Vigilant, the L-5 was the only other American liaison aircraft of World War II that was purpose-built for military use and had no civilian counterpart. All other military liaison airplanes adopted during World War II were lightly modified "off-the-shelf" civilian models.
Development
The origins of the L-5, affectionately known as the "Flying Jeep", can be traced to the prewar civilian Stinson HW-75. The 75 horsepower civilian high-wing design was built by the Stinson Aircraft Company at Wayne, Michigan and first flew in 1939. The HW-75 featured two seats up front side-by-side, and a third "jumpseat" in the rear on which a small passenger could sit sideways. The design was easy to fly. Shortly after the introduction of the HW-75, Stinson became a subsidiary of the Vultee Aircraft corporation. Under Vultee management, the HW-75 was equipped with an 80-horsepower four-cylinder engine for the 1940 model year and the HW-75 became known as the Model 105 "Voyager", touting its 105 mph cruise speed. Fitted with a four-cylinder 90 hp Franklin engine for the 1941 model year, the type became known as the Model 10A. In the postwar era, the fuselage of the Model 10A was enlarged to accommodate four seats, and the four-cylinder powerplant was replaced with a Franklin 150 hp six-cylinder engine. This conversion became the Stinson Model 108 Voyager and the only civilian aircraft commercially produced by Stinson after WWII.