Confirmed: May’s A400M airplane crash caused by software bug in the engines

It has just been confirmed that the Airbus A400M aircraft that crashed last month during a test flight near Seville, Spain, was caused by a software-related issue stemming from the deletion of key engine management files.

The results from the investigation have finally confirmed that the three of the four propeller engines malfunctioned because files known as “torque calibration parameters” were accidentally deleted during a software update ahead of the plane’s maiden flight. Airbus explained that the each of the A400M’s four engines are highly automated and run by a computer called the Electronic Control Unit (ECU), which automatically adjusts engines to respond to the pilot’s inputs in the most optimal way. 

The problem was that without the parameters files used by the ECU to interpret the torque generator by each engine, the ECU could not make sense of the data and the propellers could not be readjusted after liftoff.

For this reason, three of the four propeller engines were rotated far too slowly, and being the highly automated aircraft that it is, the ECU ignored commands issued by the pilots. Airbus confirmed that the pilots were unable to switch the affected engines out of the “flight idle mode,” or the lowest power setting. Ironically, the engines were intentionally designed in this manner to avoid malfunctioning engines from suddenly powering up and causing the aircraft to go out-of-control, and worse yet, Airbus did not foresee three propellers simultaneously stall.

“We are working closely with the official investigation, and we will act in accordance with the information that is discovered but are not able to discuss the findings,” a spokesman for Airbus told the BBC.

Nevertheless, the UK, France, Malaysia, Turkey, and Germany have already received deliveries of the plane, which were specifically created to give Europe’s NATO partners independent access to heavy aircraft for troop and weaponry transportation. They have since been grounded following the accident.

The downed A400M plane was built for the Turkish Air Force.

Source: BBC