What happened
On January 19, 2021, at 12:50 UTC, a loss of separation occurred between two aircraft operating in the Curitiba terminal area (TMA-CT), Brazil. The first aircraft, a Cessna 208B (registration PP-MMS), was departing from Bacacheri Aerodrome (SBBI) on a vaccine transport mission toward Londrina. Simultaneously, a Boeing 737-8EH (registration PR-GUC) was on approach to Afonso Pena Aerodrome (SBCT) for a scheduled commercial flight.
During the departure phase of the 208B, the aircraft deviated from its assigned RNAV SID (Standard Instrument Departure) profile. This deviation resulted in the two aircraft coming within 0.5 NM and 500 ft of each other. The crew of the 737-8EH responded to a TCAS Resolution Advisory (RA) by climbing, and the air traffic controllers at Curitiba Approach proactively instructed the Boeing aircraft to discontinue its approach, preventing a further reduction in separation. No injuries were reported, and there was no damage to either aircraft.
The investigation
CENIPA's investigation focused on the navigation deviation of the 20larB. Investigators examined the recent avionics upgrade performed on PP-MMS, which had transitioned to a modern 'glass cockpit' interface (Garmin GTN/G600) approximately five months prior to the event. The investigation reviewed flight logs, maintenance records, and air traffic control communications.
While the air traffic controllers were found to have managed the conflict effectively, the investigation identified difficulties in the operation of the autopilot's lateral NAV and HDG modes. Furthermore, investigators looked into the training provided to the crew following the avionics modernization and the organizational procedures regarding standard operating procedures (SOPs) for the aircraft's operation.