Mil Mi-12 Homer

Design work began around 1959, with construction starting in 1965. First successful flights were in 1968; and the type was formally announced in Mar 1969, with production expected to start by 1971. The crash of the first prototype later in 1969 led to a reappraisal of the concept. Only 2 prototypes were built of this huge, heavy lift transport helicopter, before the programme was cancelled.