What happened
On June 17, 2011, an Airbus A319-132, registration PT-MZC, operated by TAM Linhas Aéreas, was climbing through FL120 in the Rio de Janeiro terminal area during a flight from Santos Dumont (SBRJ) to Confins (SBCF). During the climb, the crew was alerted by Air Traffic Control to the presence of hot air balloons in the vicinity. Shortly thereafter, the aircraft collided with a plastic banner attached to a hot air balloon.
The impact caused the obstruction of all three Pitot tubes and the Total Air Temperature (TAT) sensor with plastic debris. This led to a rapid degradation of the aircraft's automated flight systems, triggering several ECAM warnings, including NAV ADR DISAGREE, F/CTL ALTN LAW, and AUTO FLT AP/A-THR OFF. The crew was forced to manage an unreliable airspeed condition for the remainder of the flight. Despite the loss of automation and discrepancies in airspeed indications between the primary flight displays, the crew successfully landed the aircraft at SBCF. There were no fatalities and no injuries among the 95 passengers and 6 crew members, though the aircraft sustained light damage.
The investigation
CENIPA's investigation focused on the impact of the debris on the aircraft's sensors and the crew's subsequent management of the emergency. Investigators found that the plastic residue from the balloon banner physically blocked the critical flight data sensors. The analysis also examined the crew's cockpit coordination and the airline's training programs. It was noted that during the emergency, the crew's management of tasks was inadequate, specifically regarding the use of the Quick Reference Handbook (QRH) and task-sharing. Furthermore, the investigation looked into the airline's training curriculum regarding unreliable airspeed procedures and the regulatory environment surrounding the release of uncontrolled balloons in Brazilian airspace.