After crash of Air France Flight 447, NTSB investigates malfunctions on two other Airbus A330 planes

The United States National Transportation Safety Board (NTSB) is investigating possible malfunctions of the airspeed sensor and altitude sensor on board Airbus A330 aircraft, the same type of plane that crashed into the Atlantic Ocean on June 1, 2009.

Flight 447 of Air France met with the accident while it was flying to Paris in France from Rio de Janeiro in Brazil. All the 228 people aboard the plane perished.

The US National Transportation Safety Board, the independent federal agency that investigates every civil aviation accident in the United States, is looking at the possible role, among others, of airspeed sensors – also called pitot tubes – as a possible cause of the crash of Flight 447.

Accident investigators in France had found that the Air France Flight 447 had sent as many as 24 automated error messages in the 4 minutes before it broke up. All these messages indicated that there were problems with in-flight information about the aircraft’s speed, which can result in some of the plane’s instruments stopping functioning.

The first of the two incidents involving the Airbus A330 aircraft that the NTSB is investigating occurred on May 21, 2009, when a flight of TAM Airlines (the flag-carrier of Brazil and the country’s biggest airline) from Miami, Florida, the United States, to Sao Paulo in Brazil lost information on primary speed and altitude.

In a statement, the US National Transportation Safety Board said the initial reports indicated that the flight crew of the TAM Airlines flight noted “an abrupt drop in outside air temperature, followed by a loss of the Air Data Reference System and disconnections of the autopilot and autothrust, as well as loss of information on speed and altitude.” Fortunately, the flight crew used backup instruments and succeeded in restoring the primary data in around 5 minutes.

A second incident, almost similar to what happed in the TAM Airlines flight, took place on June 23, 2009, when a flight of the United States-based Northwest Airlines, a wholly owned subsidiary of Delta Air Lines, was flying between Hong Kong and Tokyo in Japan.

The NTSB said its investigators were collecting information from data recorders, messages from monitoring system, weather information as well as statements from the crew of the Northwest Airlines flight.

The United States-based Delta Air Lines and US Airways as well as Ireland’s flag-carrier airline Aer Lingus had announced earlier in June 2009 that they were acting in accordance with an advisory issued by Airbus Industrie to replace the pitot tubes with an upgraded version, following the crash of the Air France Flight 447.