An ANZ Air New Zealand Avions de Transport Regional ATR-72-212A, registration ZK-MVL performing flight NZ-5366 from Christchurch to Wellington (New Zealand), was on on short final to Wellington's runway 34 about 6 seconds before touch down when the left hand engine began to emit dense smoke. The aircraft touched down, rolled out and stopped on the runway, flames became visible from the left hand engine. The crew shut both engines down while emergency services began to respond. The aircraft was evacuated. There were no injuries.
The airline reported smoke was seen from an engine, the aircraft was met by emergeny services, all passengers disembarked safely.
A passenger photo shows the left hand engine on fire. Passengers later reported the "crew chief" told them there had been a drop in the oil pressure of the engine, the oil obviously was leaking and made contact with hot parts of the engine and ignited.
On Sep 6th 2024 the ATSB reported: "During final approach, at about 300 feet, there was a low oil pressure caution, then an engine fault and engine fire warning for the aircrafts left engine. The crew declared a mayday, landed safely and stopped on the runway. Airport emergency services attended promptly, and passengers and crew were evacuated on to the runway, with no serious injuries reported." New Zealand's TAIC requested assistance by the ATSB, the ATSB assigned an accredited representative.
On Sep 24th 2026 the TAIC released their final report concluding the probable causes of the occurrence were:
- The engine fire warning was initiated by a failure of a low-pressure turbine blade, which resulted in a vibration in the engine that caused deterioration to some air seals, allowing oil to leak directly into the engine.
- It is virtually certain that the fire was extinguished shortly after the second fire-agent bottle was discharged. However, the engine fire warning remained and so the captain ordered an evacuation.
- The low-pressure turbine blade failed because of fatigue.
- A second low-pressure turbine blade also had evidence of fatigue.
- While the Commission was unable to definitively determine when the fatigue cracking originated, it was likely that the fatigue on both LPT blades was present when the engine was recently overhauled.
- Despite an initial crossed communication, the actions of the tower controller ensured the rescue fire service was able to respond promptly to the emergency.
- Video recordings obtained by the Commission, showed 12 passengers exited the aeroplane though the forward-left exit and 15 through the forward-right exit. The Commission determined that it was virtually certain that the remaining 42 cabin passengers exited using the normal entry/exit airstair door at the rear-left of the aeroplane.
- The Commission found that the evacuation took significantly longer than the certification benchmark for several reasons, including:
+ some passengers were inadequately prepared for an evacuation
+ passengers could not identify a clear threat to their safety and so did not expedite their escape
+ not all available exits were used
+ the passengers who used the two forward exits found them challenging
+ many of the passengers did not follow crew instructions, including taking their carry-on baggage with them.
- Several passengers endangered themselves after evacuating by walking near the previously burning engine and propellers.
The TAIC analysed:
The flight was uneventful until approaching Wellington, when the pilots were alerted to a low oil pressure caution for the left engine. This was quickly followed by a fire warning for the same engine. The ATR continued and landed safely.
After landing, the pilots completed the required actions for the fire warning, including discharging both bottles of fire agent into the left engine nacelle. The fire warning remained and so the captain ordered an evacuation. The fire was extinguished, with damage confined to the left engine. There were some minor injuries during the evacuation, predominantly strains encountered when jumping from the forward two emergency exits. However, all passengers were able to self-evacuate and walk to the assembly area from where they were eventually ferried to the terminal.
The actions of the flight and cabin crew ensured the safe landing and evacuation of all passengers. The following sections analyse the circumstances surrounding the event to identify those factors that increased the likelihood of the event occurring or increased the severity of its outcome. It also examines any safety issues that have the potential to adversely affect future operations.
Engine failure and examination
Safety issue 1: A low-pressure turbine blade failed because of fatigue. The engine manufacturers quality assurance procedures during the recent engine overhaul did not identify the issue, increasing the risk of other similarly faulty turbine blades re-entering service.
The engine fire warning was initiated by a failure of an LPT blade, which resulted in a vibration in the engine that caused deterioration to some air seals, allowing oil to leak directly into the engine. The resulting low oil pressure in the left engine caused the caution light to illuminate. The combustion of the oil that had seeped onto the engine produced a large volume of smoke, and the temperature within the engine nacelle increased to the point that the fire detection warning was activated.
The burning oil also resulted in flames and a large volume of smoke coming from the engine exhaust. This is what the tower controller saw when issuing the conditional line-up clearance to an aeroplane preparing for take-off. Several passengers seated on the left side of the ATR also saw the flames and smoke coming from the engine and alerted the flight attendants. Smoke or haze was observed in the cabin at the same time. This slowly dissipated.
The engine fire was detected by a sensing wire looped around the inside of the engine nacelle. An increase in nacelle temperature reduces resistance in the wire, eventually activating an engine fire warning light and alarm on the flight deck. The observations by the attending RFS personnel indicated that it is virtually certain that the fire was extinguished shortly after the second fire-agent bottle was discharged. However, because of residual heat in the engine nacelle, the engine fire warning light remained illuminated for several minutes afterwards.
Initial examination of the engine and its components by both the TSB and P&WC identified that an LPT blade had failed as the result of fatigue.
Detailed examination of the failed LPT blade by the TSB determined that there were two notably different types of fatigue topography over the fracture surface. The first type closest to the well-defined point of origin had a rubbed and flatter appearance. Outside of this area the surface was rougher with at least five distinct bands. This difference, along with the absence of any surface defect, lead the TSB to conclude that the fatigue cracking developed in the root of the blade and the crack was likely present when the blade entered service. Therefore, the crack was likely already present when the engine was overhauled.
The engine overhaul had included the removal of the LPT disc and blades. The blades were reportedly examined and fitted to a new disc before being reinstalled.
Examination of the remaining 46 LPT blades from the same low-pressure disc by P&WC identified one further blade with a crack at around the same height, but on the opposite side to the failed blade (see Figures 13 and 14). This blade was located six positions away from the failed blade. When forced open, the crack revealed a similar metallurgic feature to the failed LPT blade.
Following further examination, P&WC concluded that both blades showed fatigue propagating from a single origin or cleavage initiation site. Micro-shrinkage was identified in this area, which acted as a stress concentrator. The blades construction material was determined to meet the manufacturers specifications.
P&WC determined that the fatigue was initially high cycle but the fatigue crack spread rapidly to the point of failure over a low number of engine cycles. P&WC considered there to be eight such bands within the area of fatigue. P&WC concluded that the degree of oxidation on the surface of the cracks and the absence of evidence of the fluorescent penetrant used during the recent overhaul inferred that the cracking occurred in the four flying hours and five cycles. Further, the two non-adjacent blades the failed blade and the second cracked blade had been exposed to a similar unidentified cyclic loading stress, the exact cause of which could not be determined.
The P&WC PW100 series of engine has been in service since 1984. By 2024, over 9000 PW100 engines had been produced. The Commission was unable to identify any similar LPT blade failures involving this engine type.
At an ATR safety conference held on 30 November 2023, P&WC reported that the PW100 series engine had accumulated a total of 53 million flying hours and 57 million cycles. The highest time engine had accrued a total of 52,883 flying hours.
At the time of this occurrence, the operator had a fleet of 30 ATR aircraft with a further 3 on order. A review of the operators engine data showed that at 10,961 cycles and 11,258 hours in service, the failed engine and LPT blade were low-time when compared to the pool of over 60 engines. At least 18 of the engines had accrued over 20,000 hours.
The P&WC report did not state if the post-overhaul cracking related to both the high cycle and low number of engine cycles, or just the latter. While the failure of one LPT blade could be considered an isolated occurrence, there was similar fatigue in a second blade.
Video of short final, landing and aftermath starting 13610 seconds/3 hours 46 minutes 50 seconds into video (Video: Wellington Flights Live):
https://www.youtube.com/watch?v=0mYAEcZlLX0
The airline reported smoke was seen from an engine, the aircraft was met by emergeny services, all passengers disembarked safely.
A passenger photo shows the left hand engine on fire. Passengers later reported the "crew chief" told them there had been a drop in the oil pressure of the engine, the oil obviously was leaking and made contact with hot parts of the engine and ignited.
On Sep 6th 2024 the ATSB reported: "During final approach, at about 300 feet, there was a low oil pressure caution, then an engine fault and engine fire warning for the aircrafts left engine. The crew declared a mayday, landed safely and stopped on the runway. Airport emergency services attended promptly, and passengers and crew were evacuated on to the runway, with no serious injuries reported." New Zealand's TAIC requested assistance by the ATSB, the ATSB assigned an accredited representative.
On Sep 24th 2026 the TAIC released their final report concluding the probable causes of the occurrence were:
- The engine fire warning was initiated by a failure of a low-pressure turbine blade, which resulted in a vibration in the engine that caused deterioration to some air seals, allowing oil to leak directly into the engine.
- It is virtually certain that the fire was extinguished shortly after the second fire-agent bottle was discharged. However, the engine fire warning remained and so the captain ordered an evacuation.
- The low-pressure turbine blade failed because of fatigue.
- A second low-pressure turbine blade also had evidence of fatigue.
- While the Commission was unable to definitively determine when the fatigue cracking originated, it was likely that the fatigue on both LPT blades was present when the engine was recently overhauled.
- Despite an initial crossed communication, the actions of the tower controller ensured the rescue fire service was able to respond promptly to the emergency.
- Video recordings obtained by the Commission, showed 12 passengers exited the aeroplane though the forward-left exit and 15 through the forward-right exit. The Commission determined that it was virtually certain that the remaining 42 cabin passengers exited using the normal entry/exit airstair door at the rear-left of the aeroplane.
- The Commission found that the evacuation took significantly longer than the certification benchmark for several reasons, including:
+ some passengers were inadequately prepared for an evacuation
+ passengers could not identify a clear threat to their safety and so did not expedite their escape
+ not all available exits were used
+ the passengers who used the two forward exits found them challenging
+ many of the passengers did not follow crew instructions, including taking their carry-on baggage with them.
- Several passengers endangered themselves after evacuating by walking near the previously burning engine and propellers.
The TAIC analysed:
The flight was uneventful until approaching Wellington, when the pilots were alerted to a low oil pressure caution for the left engine. This was quickly followed by a fire warning for the same engine. The ATR continued and landed safely.
After landing, the pilots completed the required actions for the fire warning, including discharging both bottles of fire agent into the left engine nacelle. The fire warning remained and so the captain ordered an evacuation. The fire was extinguished, with damage confined to the left engine. There were some minor injuries during the evacuation, predominantly strains encountered when jumping from the forward two emergency exits. However, all passengers were able to self-evacuate and walk to the assembly area from where they were eventually ferried to the terminal.
The actions of the flight and cabin crew ensured the safe landing and evacuation of all passengers. The following sections analyse the circumstances surrounding the event to identify those factors that increased the likelihood of the event occurring or increased the severity of its outcome. It also examines any safety issues that have the potential to adversely affect future operations.
Engine failure and examination
Safety issue 1: A low-pressure turbine blade failed because of fatigue. The engine manufacturers quality assurance procedures during the recent engine overhaul did not identify the issue, increasing the risk of other similarly faulty turbine blades re-entering service.
The engine fire warning was initiated by a failure of an LPT blade, which resulted in a vibration in the engine that caused deterioration to some air seals, allowing oil to leak directly into the engine. The resulting low oil pressure in the left engine caused the caution light to illuminate. The combustion of the oil that had seeped onto the engine produced a large volume of smoke, and the temperature within the engine nacelle increased to the point that the fire detection warning was activated.
The burning oil also resulted in flames and a large volume of smoke coming from the engine exhaust. This is what the tower controller saw when issuing the conditional line-up clearance to an aeroplane preparing for take-off. Several passengers seated on the left side of the ATR also saw the flames and smoke coming from the engine and alerted the flight attendants. Smoke or haze was observed in the cabin at the same time. This slowly dissipated.
The engine fire was detected by a sensing wire looped around the inside of the engine nacelle. An increase in nacelle temperature reduces resistance in the wire, eventually activating an engine fire warning light and alarm on the flight deck. The observations by the attending RFS personnel indicated that it is virtually certain that the fire was extinguished shortly after the second fire-agent bottle was discharged. However, because of residual heat in the engine nacelle, the engine fire warning light remained illuminated for several minutes afterwards.
Initial examination of the engine and its components by both the TSB and P&WC identified that an LPT blade had failed as the result of fatigue.
Detailed examination of the failed LPT blade by the TSB determined that there were two notably different types of fatigue topography over the fracture surface. The first type closest to the well-defined point of origin had a rubbed and flatter appearance. Outside of this area the surface was rougher with at least five distinct bands. This difference, along with the absence of any surface defect, lead the TSB to conclude that the fatigue cracking developed in the root of the blade and the crack was likely present when the blade entered service. Therefore, the crack was likely already present when the engine was overhauled.
The engine overhaul had included the removal of the LPT disc and blades. The blades were reportedly examined and fitted to a new disc before being reinstalled.
Examination of the remaining 46 LPT blades from the same low-pressure disc by P&WC identified one further blade with a crack at around the same height, but on the opposite side to the failed blade (see Figures 13 and 14). This blade was located six positions away from the failed blade. When forced open, the crack revealed a similar metallurgic feature to the failed LPT blade.
Following further examination, P&WC concluded that both blades showed fatigue propagating from a single origin or cleavage initiation site. Micro-shrinkage was identified in this area, which acted as a stress concentrator. The blades construction material was determined to meet the manufacturers specifications.
P&WC determined that the fatigue was initially high cycle but the fatigue crack spread rapidly to the point of failure over a low number of engine cycles. P&WC considered there to be eight such bands within the area of fatigue. P&WC concluded that the degree of oxidation on the surface of the cracks and the absence of evidence of the fluorescent penetrant used during the recent overhaul inferred that the cracking occurred in the four flying hours and five cycles. Further, the two non-adjacent blades the failed blade and the second cracked blade had been exposed to a similar unidentified cyclic loading stress, the exact cause of which could not be determined.
The P&WC PW100 series of engine has been in service since 1984. By 2024, over 9000 PW100 engines had been produced. The Commission was unable to identify any similar LPT blade failures involving this engine type.
At an ATR safety conference held on 30 November 2023, P&WC reported that the PW100 series engine had accumulated a total of 53 million flying hours and 57 million cycles. The highest time engine had accrued a total of 52,883 flying hours.
At the time of this occurrence, the operator had a fleet of 30 ATR aircraft with a further 3 on order. A review of the operators engine data showed that at 10,961 cycles and 11,258 hours in service, the failed engine and LPT blade were low-time when compared to the pool of over 60 engines. At least 18 of the engines had accrued over 20,000 hours.
The P&WC report did not state if the post-overhaul cracking related to both the high cycle and low number of engine cycles, or just the latter. While the failure of one LPT blade could be considered an isolated occurrence, there was similar fatigue in a second blade.
Video of short final, landing and aftermath starting 13610 seconds/3 hours 46 minutes 50 seconds into video (Video: Wellington Flights Live):
https://www.youtube.com/watch?v=0mYAEcZlLX0
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