Overview
On 2 April 2019, an IndiGo Airbus A320-271 NEO (registration VT-ITG) operating scheduled flight 6E-134 from Pune to Nagpur experienced an engine stall during climb. The aircraft turned back to Pune and landed without further incident. There were no injuries to any of the 93 occupants, including 4 cabin crew members.
Flight History
The aircraft departed Pune at approximately 0529 UTC. At 0549 UTC, while climbing through Flight Level 143, the crew heard a loud bang from the left side. The Engine 1 STALL ECAM message was triggered, followed by ENG 1 EGT OVERLIMIT and ENG 1 HGH VIB. The crew reduced Engine 1 power to idle and performed ECAM and QRH procedures. Due to abnormal engine parameters—N1 vibrations at 10, N2 vibrations at 7, and EGT exceeding 1000°C—the crew decided to return to Pune. They informed ATC Pune and Mumbai of the turn-back but did not declare an emergency. After receiving clearance, the aircraft landed safely at Pune at 0608 UTC. Taxi and disembarkation were normal.
Crew Information
The captain held an ATPL and had 3,847 hours total flying experience, with 1,341 hours on type. The first officer held a CPL and had 541 hours total experience, with 341 hours on type. Both had valid medical certificates and had undergone pre-flight breathalyzer tests with negative results. Their rest periods before the flight were 17 hours.
Aircraft and Engine Details
The aircraft, an Airbus A320-271 NEO manufactured in 2016, was powered by two Pratt & Whitney PW1127G-JM engines. The left engine (serial number P770530) had accumulated 3,118 hours and 2,038 cycles since manufacture. All applicable airworthiness directives and mandatory modifications were complied with as of the incident date.
Post-Flight Inspection
A visual inspection of Engine 1's inlet and exhaust areas revealed damage to all blades of the low-pressure turbine (LPT) 3rd stage. Subsequent tear-down examination identified additional damage:
- Combustion chamber: burn marks, cracks, and coating loss.
- LPT drive shaft: score marks.
- LPT Stage 1 and 2 blades: some damaged.
- LPT Stage 3 blades: all fractured.
- LPT Stage 3 vanes: impact damage.
- LPT case and turbine exhaust case: multiple impact damages.
- Accessory gearbox metal chip detector: more than 60% metallic fines.
No damage was noted to other aircraft systems.
Weather and Communications
Meteorological conditions at Pune were clear with no relevance to the incident. Two-way communication between the aircraft and ATC was established throughout.
Flight Recorders
Both the cockpit voice recorder and flight data recorder were downloaded and used for analysis, correlating with other evidence.
Injuries and Survival
No injuries were reported among passengers or crew. The incident was survivable.
Probable Cause
No probable cause was stated in the investigation report.