Air France rushes to replace speed monitors

AIR France rushed yesterday to replace speed monitors suspected of feeding false information to the computers of Flight 447 and leading to a series of failures that broke the plane apart over the Atlantic Ocean.

Four more bodies were pulled from the sea, and helicopters began ferrying other remains to shore.

A total of 28 bodies have been recovered; 200 others have yet to be found.

Soldiers and medical personnel in surgical gowns carried off the remains in body bags at the island of Fernando de Noronha, to be flown to the coastal city of Recife, where experts will try to identify them using DNA and photos.

Identifying the bodies – knowing just where they were seated in the plane and studying their injuries – could provide clues to causes of the May 31 disaster, according to Peter Goelz, a former managing director of the National Transportation Safety Board.

With the plane’s data recorders still apparently deep in the ocean, investigators have been focusing on the possibility that external speed monitors – called Pitot tubes – iced over and gave dangerously false readings to the plane’s computers in a thunderstorm.

The L-shaped metal Pitot tubes jut from the wing or fuselage of a plane, and are heated to prevent icing. The pressure of air entering the tubes lets sensors measure the speed and angle of flight. A malfunctioning Pitot tube could mislead computers controlling the plane to dangerously accelerate or decelerate.

Air France said it began replacing the Pitot tubes on its A330 and A340 jets in May after pilots reported several incidents of icing leading to a loss of airspeed data, and that it had already replaced the Pitots in smaller A320 jets after similar problems were reported.

“What we know is that other planes that have experienced incorrect airspeed indications have had the same Pitots. And airplanes with the new Pitot tubes have never had such problems,” said Air France pilot Eric Derivry, a spokesman for the SNPL pilots’ union.

While no cause has been established for the disaster, Derivry said the Pitot failures create “a web of presumptions, but only presumptions” that they “could be a contributing factor”.

The monitors had not yet been replaced on the A330 that was destroyed en route from Rio de Janeiro to Paris.

Yesterday, the airline assured its pilots that none of its A330s or A340s would fly without at least two of the new instruments, and all Air France A330s and A340s will have all three Pitots replaced by month’s end.

Brazil’s air force, meanwhile, said that is replacing the Pitot tubes on an Airbus A319 used by President Luiz Inacio Lula da Silva because of a recommendation of the jet’s manufacturer more than a month before the Air France crash. It did not say when the change was made.

A memo sent to Air France pilots on Monday by its smaller Alter union and obtained by The Associated Press urged them not to fly unless at least two of the three Pitot sensors on each plane had been replaced, citing a “strong presumption” among its pilot members that a Pitot problem precipitated the crash.

The union’s memo also warned of a “real risk of loss of control” due to Pitot problems.

More in this section

IE_logo_newsletters

Select your favourite newsletters and get the best of Irish Examiner delivered to your inbox