The Yakovlev Yak-46 was a proposed aircraft design based on the Yak-42 with two contra-rotating propellers on the propfan located at the rear. The specification of the Samara turbofans was in the 11,000 kg (24,250 lb) thrust range. Though proposed in the 1990s, production of the Yak-46 never commenced. Design and development At the 1987 Paris Air Show, the Soviet Union displayed scale models of several aircraft in development, including a 150-seat aircraft powered by two pusher propfans mounted on the rear fuselage. This aircraft was unnamed at the time, but the Soviets disclosed that the Yakovlev Design Bureau was developing the aircraft. Later in 1987, the Soviet civil aviation minister noted that Yakovlev was building a twin-propfan airliner based on its Yak-42 model. In 1989, Yakovlev planned to test the D-236 propfan engine from the Ivchenko-Progress engine design bureau (also known as Progress, Lotarev, Muravchenko, ZMKB, and Zaporozhye) in flight on a Yak-42 testbed aircraft by the end of the year. Yakovlev revealed details in early 1990 about Yakovlev's propfan design, which was given the name of Yak-46 and planned to enter service in 1997. The Yak-46 and the Yak-42M, a of the Yak-42 that would enter service in 1994, would have fly-by-wire (FBW) controls, an electronic flight instrument system (EFIS), a supercritical airfoil wing of added aspect ratio, span, and sweep, seating capacity of 150 passengers or more, and new engines with thrust reversal capability. However, the Yak-46 would have two unshrouded propfan engines mounted on the aft fuselage, instead of the Yak-42 and Yak-42M's three aft-mounted turbofan engines (that includes one attached to the vertical stabilizer). Yakovlev also proposed an unnamed interim derivative situated between the Yak-42M and the Yak-46, which would be powered by two underwing engines based on the contra-rotating, integrated, shrouded propfan (CRISP) engine concept. Since this derivative required greater airframe changes, Yakovlev was less sure of its eventual production. The Yak-46 would hold 150-162 seats in a six-abreast, single-aisle configuration, fly as far as , cruise at a speed of , and be powered by two Lotarev D-27 propfan engines. The propfan engines would have contra-rotating propellers with eight blades in front and six blades in back, have a thrust specific fuel consumption of , and deliver , resulting in a thrust of . The fuel consumption per available seat kilometer of the Yak-46 was per seat. This value compared to for the