Progress D-236

The front propeller was tested on the Antonov An-32 military transport aircraft in 1980, as the An-32's normal Ivchenko AI-20DM engines had about half the rated power of the D-236.

The increased noise affected radio communications and crew working conditions, so the propeller testing was quickly ended.

The D-236 used the gas generator of the 8,500 kW (11,400 shp) Lotarev D-136 turboshaft engine, but added a planetary gearbox to drive the propellers.

The D-136 itself had a core that was based on the Lotarev D-36,[7] a 6,500 kilograms-force (14,000 pounds-force; 64 kilonewtons) static thrust turbofan that entered service in the previous decade and powered the Antonov An-72, An-74, and Yakovlev Yak-42 Soviet airliners.

[13] The Yak-46 would have a base capacity of 150 seats, a range of 1,900 nautical miles (3,500 km; 2,200 mi), and a cruise speed of Mach 0.75[14] (460 kn; 850 km/h; 530 mph; 240 m/s; 780 ft/s).

[16] In addition, the Soviet Union considered using D-236 propfan engines on these publicly proposed aircraft: Although in November 1991, the Hamilton Standard propeller manufacturing division (and inventor of the propfan concept in the 1970s) of United Technologies was to meet with a Soviet aerospace delegation to discuss involvement in the D-236 project,[21] the engine never made it into service.

The breakup of the Soviet Union plunged the successor states into financial troubles, which prevented further development of the D-236 and aircraft that would use that powerplant.