U.S. safety officials said Thursday they are investigating two incidents in which airspeed and altitude indications in the cockpits of Airbus A330 planes may have malfunctioned.
The aircraft are the same type as the Air France plane that crashed into the Atlantic Ocean just off Brazil on May 31 after sending out low airspeed messages, killing all 228 aboard.
The National Transportation Safety Board said in a statement that the first incident occurred May 21, when TAM Airlines Flight 8091 flying from Miami to Sao Paulo, Brazil, experienced a loss of primary speed and altitude information while cruising.
Initial reports indicate that the flight crew noted an abrupt drop in the outside air temperature reading, followed by disconnection of the autopilot and autothrust, along with the loss of speed and altitude information, the board said. The flight crew used backup instruments, and airspeed and altitude data were restored in about 5 minutes, the board said.
The board only recently became aware of the incident, but it confirmed the event through the Brazilian government.
Information on the second incident is more sketchy, but it involves a Northwest Airlines flight from Hong Kong to Tokyo on Tuesday, the board said.
Data recorder information, aircraft condition monitoring system messages, crew statements and weather information involving that flight are being collected by NTSB investigators.
In both cases the planes landed safely, and no one was injured, the board said.
Air France Flight 447 came down in the Atlantic after running into thunderstorms en route from Rio de Janeiro to Paris. The Brazilian military has led the search and recovery efforts for bodies and debris, while the French are in charge of investigating the crash and the hunt for the flight recorders, or black boxes.
The cause of the crash is unclear.