The Witteman-Lewis XNBL-1 (Experimental Night Bomber, Long Range) was an early attempt to produce a heavy bomber for the United States Army Air Service in the early 1920s. The oft-repeated nickname of “Barling Bomber” comes from its designer, an Englishman named Walter Barling, who had worked on similar large bomber concepts for the Royal Aircraft Factory during World War I. One of the leading proponents of the XNBL-1 project was Gen. William “Billy” Mitchell. When it was completed in 1923, the Barling was one of the largest aircraft built to date, with a wingspan of 120 feet, a 5,000-pound bomb load, and a maximum takeoff weight of more than 45,000 pounds. It also had some of the features that would appear on bombers of the 1930s and 1940s, such as separate crew stations, an enclosed bomb bay, and multiple defensive gun positions. Ultimately the concept behind the Barling — a long-range heavy bomber — was too ambitious for 1920s technology. Its three wings, four rudders, 10 landing wheels, and all of the struts and bracing wires needed to hold it together did much to cancel out the thrust of its six Liberty 12A engines. Fully loaded, the aircraft barely managed 96 mph and had a range of only 170 miles. Only a single Barling was built, and it was finally scrapped in 1930.