Swiss (LX/SWR) has announced that it has grounded its fleet of 29 Airbus A220 aircraft, including nine A220-100s and 20 A220-300s. The airline decided to ground the fleet due to the diversion of a flight, originally bound for Geneva from London, to Paris.
The deicision comes unexpectedly, as the airline has operated the aircraft consistently for years. This means that many short-haul flights from Zurich and Geneva are cancelled.
Swiss released the following statement regarding the grounding:
“In view of the further incident with a C Series / Airbus A220 engine, SWISS has decided to conduct engine inspections for its entire C Series / A220 fleet. This means that all SWISS C Series / A220 aircraft will undergo an extensive examination from midday today (15.10) onwards. Only following a faultless inspection will these aircraft be returned to regular flight duties. This will put substantial restrictions on SWISS’s flight operations, as numerous flights will have to be cancelled.
“SWISS takes these incidents very seriously, and is in close dialogue with the relevant authorities, with Airbus Canada and with the engines’ manufacturer (Pratt & Whitney). The safety of our customers and our crews is our paramount priority. We will do everything we can to return the operation of our C Series fleet to normal as soon as possible and continue to ensure safe flight operations.
“We deeply regret the inconvenience to the customers affected. All the travellers concerned will be proactively informed of these developments, provided they gave SWISS their contact details when they booked their flight. They will also be rebooked at SWISS’s expense onto the best possible alternative. Passengers with bookings for any of these cancelled flights may also rebook free of charge or have their ticket price refunded.”
This incident is the third uncontained engine failure in three months. After the second such failure, the United States’ FAA released the following Air Worthiness Directive:
“The FAA released an Air Worthiness Directive 2019-19-11 requiring following actions on Pratt & Whitney Models PW1519G, PW1521G, PW1521GA, PW1524G, PW1525G, PW1521G-3, PW1524G-3, PW1525G-3, PW1919G, PW1921G, PW1922G, PW1923G, and PW1923G-A turbofan engines that have accumulated fewer than 300 flight cycles:
(1) Within 50 flight cycles from the effective date of this AD, and thereafter at intervals not to exceed 50 flight cycles until the engine accumulates 300 flight cycles, borescope inspect each LPC inlet guide vane (IGV) stem for proper alignment.
(2) Within 50 flight cycles from the effective date of this AD, and thereafter at intervals not to exceed 50 flight cycles until the engine accumulates 300 flight cycles, borescope inspect the LPC R1 for damage and cracks at the following locations:
(i) The blades tips;
(ii) the leading edge;
(iii) the leading edge fillet to rotor platform radius; and
(iv) the airfoil convex side root fillet to rotor platform radius.
(3) As the result of the inspections required by paragraphs (g)(1) and (2) of this AD, before further flight, remove and replace the LPC if:
(i) An IGV is misaligned; or
(ii) there is damage on an LPC R1 that exceeds serviceable limits; or
(iii) there is any crack in the LPC R1.
The FAA received reports of two recent IFSDs on PW PW1524G-3 model turbofan engines. The first IFSD occurred on July 25, 2019, and the second IFSD occurred on September 16, 2019. These IFSDs were due to failure of the LPC R1, which resulted in the LPC R1 releasing from the LPC case and damaging the engine. LPC rotor failures historically have released high-energy debris that has resulted in damage to engines and airplanes (see Advisory Circular (AC) 39-8, “Continued Airworthiness Assessments of Powerplant and Auxiliary Power Unit Installations of Transport Category Airplanes,” dated September 8, 2003, available at rgl.faa.gov). Although these IFSDs occurred on PW PW1524G-3 model turbofan engines, the FAA is including PW PW1900 engines in the applicability of the AD because similarities in type design make these engines susceptible to the same unsafe condition as PW PW1500 engines.
This condition, if not addressed, could result in the uncontained release of the LPC R1, in-flight shutdown, damage to the engine, damage to the airplane, and loss of control of the airplane. The FAA is issuing this AD to address the unsafe condition on these products.”
The aircraft are not expected to be grounded on a permenant basis, as each aircraft will become airborne once again once it has passed inspection.