The smoke incident on an Air Tanzania Airbus A220-300 on February 24, was the third such occurrence on the type in the space of seven months and has once again drawn global attention to the teething engine issues that continue to plague the type.
Air Tanzania held a media briefing on Thursday where it shared details of the events surrounding one of its flights, a service from Dar es Salaam to Mbeya operated by an Airbus 220-300.
Air Tanzania Managing Director Ladislaus Matindi said one of the PW 1500G engines that power the aircraft experienced overheating 30 minutes into the flight, prompting the crew to shut down the powerplant. Smoke filled the cockpit and the passenger cabin for a brief period, but dissipated after the affected powerplant was shut down.
Matindi downplayed the incident saying it posed no imminent danger to the flight and that the crew had responded professionally when they shut down the engine and turned back to Dar es Salaam.
Matindi further revealed that the event occurred about 30 minutes after departure from the gate.
One of the four A220s owned by Air Tanzania, the engines on the incident aircraft had just returned from the maintenance shop. The carrier was in 2022, forced to ground three of its A220s, following engine glitches that were associated with manufacturing defects.
The plane incident bears similarity to two other incidents in Canada and the United States, in which smoke filled the cockpits of two different A220s.
On August 24, 2023, Air Canada flight AC447 from Ottawa to Toronto, experienced smoke in the cockpit during final approach to the runway.
A similar incident would happen to a Delta Airlines flight on December 10, 223, when smoke was detected in the cockpit of flight DL 2380 from New Orleans to New York. This also happened during the landing phase of the flight.
The PW Geared Turbofan engine series, which also power the Airbus A320 family and the Embraer E-Jet E2 and the Ikurt MC-21, came into the spotlight after several inflight shutdown incidents, triggered by overheating, premature wear and inflight failure of key components.
Read: Air Tanzania grounds A220s, weighs options
Many overheating incidents happened as the aircraft approached 29,000ft, described as the top-of-climb. This is a phase of flight when the engines spin faster as they power the aircraft to cruise level. To mitigate this, operators have been advised to fly the aircraft manually through this phase and only engage the auto-pilot once in the cruise.
The Federal Aviation Administration and the European Aviation Safety Agency have responded with a number of airworthiness directives which have forced operators to ground fleets.
Last year, Indian operator Go First, which had a large number of A220s in its fleet went burst. It placed the blame on problems with the PW 1500G engines, which made many aircraft unavailable, making it difficult to meet its financial obligations.
Pratt and Whitney have responded with a number of software patches and hardware redesigns, but supply chain disruptions due to the Covid-19 pandemic, have resulted in a large number of engines, which require fixing.