The Mi-4 was designed in response to the American H-19 Chickasaw and the deployment of U.S. helicopters during the Korean War. While the Mi-4 superficially resembles the H-19 Chickasaw, it is a larger helicopter and is able to lift more weight. The first model entered service in 1952, and replaced the Mi-1. The helicopter was first displayed to the outside world in 1952 at the Soviet Aviation Day in Tushino.
