The probe into Air India flight AI2379 has taken a major turn after the pilot-in-command reportedly failed a second drug test, with sources saying it tested positive for marijuana. The Phuket-Delhi flight had suddenly lost around 300 feet of altitude, leaving several passengers injured. The findings have raised fresh aviation-safety questions as the AAIB investigates the incident. Civil Aviation Minister Ram Mohan Naidu has said there can be no compromise on flight safety.