Curtiss C-46 LV-GGJ was to fly 7 race horses from Buenos Aires to Lima via Santiago de Chile. A VFR flight plan was filed with a cruising altitude of 3000 m. The plane took off at 11:04, about one hour late. The crew reported enroute over Junin (11:59), General Soler (13:10) and San Luis (14:00). At that time the weather had changed completely. The crew reported over San Rafael (14:34) estimating El Yeso at 15:35 and then requested clearance to climb to 6000 m. Nothing more was heard from the flight. The plane appeared to have crashed into a mountain peak at 4500 m following structural failure. The wreckage of the aircraft was found on 21 November 1961 by an inhabitant of the El Sosneado area. PROBABLE CAUSE: “The aircraft flew into extremely violent turbulence, was subjected to stresses greater than those for which it was designed, and in-flight structural failure resulted. Contributing causes were: 1) insufficient preparation for the flight; 2) inadequate arrangements for the secure carriage of the livestock; and 3) the pilots failure to familiarize himself with the prevailing weather conditions.”