in particular it was not all-weather capable. The Mi-28N was unveiled in 1995, the N designation meaning "night". The prototype (no. 014) first flew on 14 November 1996. Its most significant feature is a radar in a round cover above the main rotor, similar to that of the American AH-64D Apache Longbow. The Mi-28N also has improved tor vision and an aiming device under the nose, including a TV camera and FLIR. Due to funding problems, development was interrupted. A second prototype with an improved rotor design was unveiled in March 2004 at Rosvertol. The first serial Mi-28N was delivered to the Army on 5 June 2006. By 2015, 67 Mi-28Ns were planned to be purchased, when the Mi-24 was to be completely replaced. The Rostvertol plant delivered about 140 Mi-28N and Mi-35M helicopters in 2012–14 to domestic and foreign customers; 28 helicopters were delivered in 2015. Mil also developed an export variant of the Mi-28N, designated Mi-28NE, and a simpler day helicopter variant, the Mi-28D, based on the Mi-28N design, but without radar and FLIR. A fifth-generation derivative, dubbed Mi-28NM, has been in development since 2008. According to then chief executive officer at Russian Helicopters Andrey Shibitov, the criteria for the modernized helicopter include low-radar signature, extended flight range, advanced weapons control system, some capability of a fighter jet and speed up to 600 km/h. In 2016, Russian media reported a new, advanced helmet system designed to display visual information for aiming at targets in any field of view was under development for the MI-28N. Design The Mi-28 is a new-generation attack helicopter that functions as an air-to-air and air-to-ground partner for the Mi-24 Hind and Ka-50 Hokum. The five-blade main rotor is mounted above the body midsection, short, wide, tapered, weapon-carrying wings are mounted to the rear of the body midsection. Two turboshaft engines in pods are mounted alongside the top of the fuselage with downturned exhausts. The fuselage is slender and tapers to the tail boom and nose. It features tandem, stepped-up cockpits, a cannon mounted beneath the belly, and a non-retractable tricycle tail-wheel type landing gear. Due to the energy-absorbing landing gear and seats the crew can survive a vertical fall of up to 12 m/s. The Mi-28 has a fully armoured cabin, including the windshield, which withstands 7.62 and 12.7 mm armor piercing bullets and 20 mm shell fragments. The helicopter design is based on