What happened
On December 6, 2018, a Jet Airways ATR 72-500, registration VT-JCN, was operating a scheduled flight from Indore to Delhi. Shortly after departing Indore at 1515 UTC, the aircraft climbed to flight level 150. During the climb, the flight crew observed a fire warning for the right-hand engine. Simultaneously, a passenger alerted the cabin crew to visible flames emanating from the engine area.
The pilots immediately initiated emergency procedures, which included the discharge of a single fire extinguisher squib to contain the flames. The crew declared a "MAYDAY" to Nagpur ATC and prepared for an emergency return to Indore. Despite the engine fire, the aircraft maintained stable flight on a single engine. Indore airport declared a full emergency, positioning fire tenders and ambulances along the taxiways. The aircraft landed safely on Runway 25 at 1607 UTC, and all 66 passengers and 4 crew members disembarked without injury.
The investigation
AAIB India investigators examined the aircraft's maintenance history and engine components. Post-flight inspections of the right-hand engine revealed significant internal damage, including broken oil scavenge tubes, a cracked turbine casing, and damage to thirteen power turbine blades. The investigation also reviewed the airline's previous engine-related occurrences, noting that the fleet had experienced several prior incidents involving power turbine blade failures.
Findings
- The aircraft and engines were maintained according to approved schedules and held valid airworthiness certificates.
- The flight crew was fully qualified and current for the operation.
- The engine was in compliance with Service Bulletin 21876, which was intended to prevent blade failure caused by sulfidation, but it was not in compliance with the subsequent SB 22917, which had been introduced to revert to more durable, uncoated blades.
- A definitive cause for the engine failure could not be established because the engine was moved into the custody of the lessor following the airline's financial collapse, preventing a full disassembly and failure analysis.
Safety action
- The AAIB recommended that the DGCA establish regulations to ensure investigators maintain control over wreckage and components owned by lessors during accident investigations.
- It was suggested that the DGCA verify with the AAIB if any components are required for investigation before an aircraft is deregistered.