Air India Boeing 777 engine malfunctioned at Delhi airport. What happened?

When an engineer was doing a routine technical examination of the empty aircraft at Delhi airport, the auxiliary power unit shutdown

New Delhi: The engine of an empty Boeing 777 aircraft of Air India which was scheduled to fly from New Delhi to San Francisco on Thursday is believed to have caught fire at Delhi airport. On Wednesday night, the engine of the Air India aircraft shut down during a technical inspection, Air India said.

Airport fire personnel then observed black fumes emanating from the engine's exhaust. Immediately, foam was sprayed on it, the state-owned airline said in a statement on Thursday.

What happened?

According to Air India, when an engineer was doing a routine technical examination of the empty aircraft at Delhi airport on Wednesday night, the auxiliary power unit (APU) shut down automatically. The APU is the smallest engine on the aircraft that is located at its tail. It provides the necessary power to start the main engines.

During the inspection, airport officials noticed black fumes emerging from the APU exhaust and sprayed foam on the APU and part of the fuselage, the airline said.

'No traces of burn found'

"The APU was examined by opening its cowlings (cover). After opening the cover, there were no traces of any burn or external damage noticed except for the minor oil leaks traces, which was normal," the statement said. A detailed inspection is underway, it added.