Airbus previously revealed that the fatal crash of a military transport Airbus A400M was caused by what has been described as a “quality problem in the final assembly” of the electronic control units (ECUs) – a misconfiguration software that resulted in loss of control of the aircraft and resulted in the death of four crew members. Reuters reported additional details today provided by people familiar with the crash investigation, stating that a critical portion of the configuration data in three of the aircraft’s four ECUs – a file storing torque calibration parameters for each engine – was somehow “accidentally erased” during software installation. As a result, three of the aircraft’s engines automatically shut down in flight.
Citing a safety document shown to Reuters, Tim Hepher said the A400M pilot would not have received an alert about the missing data until the plane was already at an altitude of 400 feet. No cockpit alert regarding the data failure would appear while the aircraft was on the ground. According to Hepher’s sources, the lack of a ground warning was an issue raised during a safety review last year, but “rregulators approved it on the basis that the risks of failure were low and that the installation procedure included additional checks, ”people familiar with the matter said.
The A400M, which was on a final test flight before being delivered to the Turkish Air Force, reached an altitude of 1,725 feet after take-off before crashing during an attempted emergency landing. The plane struck a utility pole at about 180 miles per hour.
The missing data prevented the aircraft’s central control system from interpreting data from the engine sensors. The aircraft software is designed to shut down faulty engines to prevent them from affecting the operation of the aircraft. But a software failure of more than two engines was never taken into account.
The data erasure appears to have been caused by the computer system used to install the flight control software and update the calibration data. Airbus has asked its European NATO buyers of the A400M not to use this software. Security officials are still investigating how security checks failed to detect that calibration data had been deleted.