Before the appearance of the now famous silhouette of the Mi-24 Hind D/E, there were a few transitional models that preceded them and are almost forgotten. These were the true hybrid attack transports that were very large versions of the UH-1C Huey Hog.
The Mi-24 series first started development in the late 1960s following the success of the AH-1 Cobra in combat. As the AH-1 was developed using the power train from the UH-1 Huey, the Mil Design Bureau also saved development time by adapting key airframe and powerplant components from the Mi-8 Hip/Mi-14 Haze family. The Mi-24 was closer in development to the UH-1C Huey Hog, as it not only carried an impressive array of firepower on its stub wings, it also retained the ability to carry troops in its cabin.
The first versions of the Mi-24, NATO Codenamed Hind A, featured a greenhouse cockpit housing the pilots and gunner. This was essentially an Mi-8 Hip with a larger cockpit to accommodate the gunner and to provide greater visibility to the pilots. Variations of this design would yield the Hind B and C models, but the same problem plagued the pilot - poor visibility out one side of the aircraft because of the copilot accommodations. This was later resolved by deleting the copilot, narrowing the cockpit to a tandem two-place similar to the AH-1 Cobra, and upgrading the armor protection around both crewmembers - that design became the Hind D.