Aeropesca Colombia Flight 221 Aeropesca Colombia Flight 221 Aeropesca Colombia Flight 221 was an internal scheduled passenger flight from Florencia Airport to Neiva Airport in Colombia. On 26 August 1981 it was being operated by a Vickers Viscount turboprop airliner registered in Colombia as "HK-1320" when it collided with Mount Santa Elana, an Andean mountain peak, destroying the aircraft and killing all 50 on board. The investigation by the Colombian authorities concluded the probable cause was "continuing VFR in meteorological conditions below the minimum laid down in the Manual of Colombian air routes". The aircraft was a four-engined Vickers Viscount 745D turboprop airliner registered
Turboprop a turboshaft. Alan Arnold Griffith had published a paper on turbine design in 1926. Subsequent work at the Royal Aircraft Establishment investigated axial turbine designs that could be used to supply power to a shaft and thence a propeller. From 1929, Frank Whittle began work on centrifugal turbine designs that would deliver pure jet thrust. The world's first turboprop was designed by the Hungarian mechanical engineer György Jendrassik. Jendrassik published a turboprop idea in 1928, and on 12 March 1929 he patented his invention. In 1938, he built a small-scale (100 Hp; 74.6 kW) experimental gas turbine. The larger Jendrassik