Light liaison airplanes, affectionately known as L-birds, were indispensable in World War II, serving as artillery spotters, light transports, and even flying ambulances. Take a look back to EAA AirVenture Oshkosh 2016, when we celebrated many of these unsung heroes like the massive Stinson L-1, the ubiquitous Piper L-4, and the original grasshopper, the Aeronca L-3.