what was the first battle plane
Russia was the first to develop an airplane specifically for this purpose: the Murometz, a large four-engine airplane that Igor Sikorsky had developed in 1913 as a passenger plane, was adapted for use as a bomber in 1914 and was used successfully throughout the war.
Aviation and Aircraft of WWI. World War I was the first major war where airplanes were used as a significant part of the military. The airplane was invented by the Wright Brothers in 1903, just 11 years before the start of World War I.