sentences:  CENIPA concluded that the accident was caused by air traffic control (ATC) errors combined with mistakesincluding a failure to recognize that their traffic collision avoidance system (TCAS) was not activatedmade by the American pilots on the Legacy, while the NTSB determined that both flight crews acted properly and were placed on a collision course by ATC, deeming the Legacy pilots' disabling of their TCAS system to be only a contributing factor rather than a direct cause.The accident, which triggered a crisis in Brazilian civil aviation, was the deadliest in Brazil's aviation history at the time.It remains the second worst plane crash in Brazil, after TAM Airlines Flight 3054 in 2007.