Air France faces new safety probe after Boeing 777 freighter scare

PARIS (Reuters) – Air France faces its second safety investigation in as many weeks after pilots were forced to recover in mid-takeoff after entering the wrong data into the computer of a cargo jet, airline and safety officials said.

The mistake over the plane's weight was discovered when the Boeing 777 freighter accelerated too slowly on the runway at Paris Charles de Gaulle airport on May 22.

Underestimating the weight can result in a plane trying to perform its takeoff without enough thrust or speed, increasing the risk of hitting the ground with the tail or overshooting the end of the runway.

A person familiar with the matter said the weight entered into the system of the Mexico-bound jet was drastically lower than the correct value, lagging by as much as 100 tonnes, which is more than a quarter of its maximum takeoff weight.

To compensate, pilots had to override previous settings and throttle the aircraft's two engines to their maximum to avoid scraping the ground with the back of the plane.

Air France confirmed the incident in response to a query from Reuters and said the crew had been taken off flying duties after reporting the error on reaching their initial destination.

"Having understood that the airplane was accelerating too slowly, the crew immediately reacted and applied full power. The aircraft then took off normally," an Air France spokesman said in an emailed statement.

A spokeswoman for France's BEA air crash investigation agency said it had launched an investigation in addition to the airline's internal inquiries.

"I confirm that an investigation has been opened in response to information provided by Air France," she said.

It is the second time this month that Air France has grounded one of its crews and faced a BEA investigation after a Boeing 777 jetliner narrowly avoided hitting Mount Cameroon, an active volcano and the highest peak in Central Africa.

In both incidents, the airline said crew had identified the problems in time and responded correctly.

The BEA has already alerted the industry to the risks of inserting faulty data into modern cockpit systems.