 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.The origins of the L-5, affectionately known as the "Flying Jeep", can be traced to the prewar civilian Stinson HW-75.