Passengers and crew on board an Air India Express flight from Tiruchirappalli in Tamil Nadu to Dubai escaped a disaster early on Friday when the aircraft's wheels hit the airport's outer wall while taking off.Although parts of the Boeing B737-800's undercarriage were damaged, the pilots, unaware of the accident, continued to fly until the airport staff informed them about the damage to the plane, which was diverted to Mumbai and landed there four hours later around 5.40 a.m.The flight IX-611, with 130 passengers and six crew, had taken off at around 1.20 a.m."We informed the pilot about the hit," Trichy Airport Director K. Gunasekaran told IANS on telephone."The pilot said nothing was wrong with the plane as the systems were functioning normally. But we found some parts of the plane like an antenna on the ground. Later the flight was diverted to Mumbai," Gunasekaran said.The official said the plane had hit the airport's instrument landing systems.A portion of the nearly five foot tall compound wall at the Trichy Airport was damaged, an airport official told IANS."The total length of the runway is 8,200 feet. The takeoff point would vary depending on the type of aircraft," he said.Queried about the load carried by the plane and its capacity, he said the details were being collected.Once the aircraft made a safe but emergency landing in Mumbai, the passengers were flown to Dubai in another plane with a fresh set of crew.Pending investigation, Air India has derostered both Captain D. Ganesh Babu, who has flying experience of 3,600 hours on Boeing 737 including 500 hours as commander, and co-pilot and First Officer Captain Anurag, who has flying experience of around 3,000 hours.Authorities have started a probe into the accident while technicians in Mumbai were examining the damaged aircraft.Tamil Nadu Tourism Minister N. Natarajan visited the Trichy airport and inspected the damage.Commenting on the incident, Civil Aviation Minister Suresh Prabhu said he had recently ordered putting in place a third-party professional organisation to look into various safety aspects at Air India."In order to have continuous attention towards air safety, I have also ordered concerned officials to put in place a regular 'safety compliance report' of all airlines. Safety of passengers is of paramount importance for us," the Minister said.Prabhu added that aviation "growth can't be at the expense of safety".