All three hydraulic systems on the Air India flight from Thailand’s Phuket to Delhi that dropped 300 feet, briefly failed, leaving the aircraft without elevators and ailerons for 4 seconds, a preliminary report by Airbus has found.
The preliminary report from the French aircraft manufacturer, prepared on the day of the incident, stated that the aircraft experienced loss of hydraulic pressure in its Green, Blue, and Yellow hydraulic systems, resulting in a temporary loss of elevator and aileron control surfaces for about four seconds. The pilots have been off-rostered pending the probe, and the incident was classified as serious. An aircraft accident is an occurrence associated with operations—from boarding to disembarkation for manned flights, or from being ready to move to shutdown for unmanned flights—resulting in serious injury, fatal injury, structural damage, or the aircraft being missing Airbus is assisting the Aircraft Accident Investigation Bureau (AAIB), which began a probe into the incident immediately after it was reported, according to ICAO Annex 13. Soon after the incident on August 4, the aircraft, with 137 passengers and eight crew members on board, stabilised and landed safely in Delhi.
The aircraft pitched up, the autopilot disconnected, and the First Officer or the co-pilot who was the pilot flying the aircraft applied nose-down input before the flight-control surfaces recovered as hydraulic pressure returned, the report added.
“In his statement to the AAIB, the PIC said he was experiencing sleep difficulty over a preceding period related to personal circumstances for which he was prescribed medication by a family doctor,” one of the persons said, seeking anonymity.
The PIC in question was on medication for “sleep difficulty”, people familiar with the matter told HT on Wednesday , adding that the revelation was made by the pilot before an AAIB team during the course of investigation.
