The Soviet made Mil V-12 (Also referred to as the Mi-12, NATO reporting name "Homer") is the largest helicopter ever built. The name "Mi-12" would have been the name for the production helicopter. Since the V-12 never went into production and only two prototypes were built, the name "Mi-12" was never adopted.
The V-12 features the only two-rotor transverse scheme ever built by Mil eliminating the need for a tail rotor. The twin engines were taken together with the rotors from the Mil Mi-6 and duplicated on the V-12. Being the first time used by Mil, the twin rotos transvers scheme was not new. It was first seen in the Focke-Wulf Fw 61 the first fully controlable helicopter from 1936. Later other helicopter used the scheme such as the Focke Achgelis Fa 223 Drache from 1940. The Soviet Kamov OKB built an experimental aircraft with the same scheme in 1958, Kamov Ka-22 Vintokryl . This aircraft had also the combined wing/rotor arrangement later used on the Mil V-12.
