A Jet Airways flight coming in to land in Mumbai in October lost height faster than the prescribed rate of descent as the auto-pilot tripped, the flight director disappeared and the ground-proximity warning system went off. The flight finally landed safely with none of its passengers hurt or even aware how close they had come to disaster, but for the experienced pilot and tons of luck. The dangerous turn of events began about 3,700 feet above the ground, when a check pilot, seated behind the commander and the first officer on the Jet Airways Delhi-Mumbai flight, pulled out a circuit-breaker. He did it ostensibly to check the pilot's ability to handle an emergency. The unthinking act set off a chain reaction, tripping the autopilot, making the flight director indications disappear and turning off the ground-proximity warning system. The aircraft went sinking at a rate faster than the maximum prescribed descent of 1,000 feet per minute over the hills behind Jarimari, Andheri, but despite all this the aircraft managed to make a safe landing.<br/><br/>The Jet Airways has ordered a probe into the incident. A Jet Airways spokesperson said the flight had a normal approach and landing, carried out safely within the acceptable parameters.<br/><br/>The Directorate-General of Civil Aviation also has initiated an inquiry into the incident.<br/>The incident took place on October 20 on flight 9W 332 around 8.50am, during the morning peak hour.<br/>