a crash of the first MD-12 prototype on 17 September 1963 near Grójec. The plane crashed due to flutter of tail control surfaces and a crew of 5 were killed. Operational service The prototype MD-12P (SP-PBD) was evaluated by the LOT Polish Airlines in August–September 1961, on Warsaw-Rzeszów route, carrying over 1700 passengers. It was also used in 1961 and 1962 on Warsaw-Poznań route, taking trips to Poznań International Fair. Design The MD-12 was a four-engined low-wing cantilever monoplane of all-metal construction, duralumin-covered. The fuselage was a semi-monocoque. The crew cockpit in front with a crew of two pilots. Passenger cab with 20 seats, three in a row. In the rear there was a toilet. Fuselage had doors in front part. In a fuselage nose there was a baggage space for 200 kg. Trapezoid three-part wing. Single tailfin. Engine nacelles in wings. Two-blade wooden propellers WR-1A of a variable pitch, 2.2 m diameter (powerplants were adapted from the TS-8 Bies trainer). Retractable tricycle landing gear – main gear with single wheels retractable to inner engine nacelles. Fuel tanks 1160 L in wings (cruise fuel consumption 240 L/h). Variants MD-12 Prototype. One built, registered as SP-PAL. MD-12P Passenger version. One built, registered as SP-PBD. MD-12F Aerial photography version with glazed nose and increased wing span. One built, registered as SP-PBL. Operators LOT Polish Airlines Survivors The MD-12F is preserved in the Polish Aviation Museum in Kraków, from 1967. Specifications (MD-12F) See also References Taylor, John W. R. Jane's All The World's Aircraft 1965–66. London: Sampson Low, Marston & Company, 1965. External links MD-12F photo MD-12 Four-engined tractor aircraft Low-wing aircraft MD-12 Aircraft first flown in 1959 Four-engined piston aircraft