The Tupolev I-12 (also known as ANT-23) was a prototype Soviet fighter aircraft that never reached production. I-12 was of unconventional design with twin booms made of water pipes containing recoilless rifles and two engines in a push-pull configuration. The aircraft first flew in 1931 but did not enter production due to disappointing performance and operational difficulties such as the inability for the pilot to escape the aircraft without hitting the propeller arc behind him. The second prototype, designated ANT-23bis was never completed.