Read our Privacy noticeThe captain of an Air India flight that experienced a sudden loss of altitude earlier this month has tested positive for cannabis use, it has been reported. Air India has been hit by series of safety-related investigations since the Ahmedabad crash ( Reuters )Investigators were also examining evidence pointing to potentially significant problems with the aircraft’s systems. Hydraulic systems use pressurised fluid to operate a jet’s flight controls, landing gear, brakes and other heavy mechanical components. Air India said in an initial statement that the flight “experienced a brief in-flight turbulence-related event during cruise, resulting in a momentary change in altitude”. The incident marks the latest blow to Air India, which is facing a series of safety-related investigations.