Curtiss C-46 PP-VBI departed S?o Paulo at 11:23 for a flight to Porto Alegre. Some 20 minutes prior to the estimated time of arrival a fire in cargo hold ‘G’ was noted. The pilot executed an emergency descent while the mechanics tried, in vain, to extinguish the fire. The flight crew members were not able to see their instruments due to heavy smoke and had to keep their heads out of the window to carry out an emergency landing in hilly terrain. The passengers crowded in panic at the forward end of the cabin in an attempt to escape from the fire. This caused a dangerous and sudden change in the Centre of Gravity of the plane. The aircraft swung violently during the landing on rough ground. PROBABLE CAUSE: “The cause of the fire in the Hold ‘G’ of the aeroplane was not determined by the investigation board who evidently assumed that several possibilities may have existed such as the ignition of inflammable material contained in cargo or passenger baggage, or through a live cigarette butt falling through an open cargo tie ring hole or open rivet hole in the cabin floor – considered a very remote possibility. The report states that several passengers, possibly students on board brought petroleum jars from Bahia, and some suspicion is expressed related to this incident.”