Swiss has started returning some of its Airbus A220s to flight status, following urgent engine checks triggered by another powerplant failure.
Restoration of A220 flight operations could be achieved on 17 October based on the carrier's planning, according to Airbus.
A220 operators are being advised of low-pressure compressor speed limitations as well as one-off visual borescope inspections as part of a precautionary set of measures.
Airbus says they are being introduced until the root cause of the problems are identified.
The latest failure of the type's Pratt & Whitney PW1500G engine, involving a Geneva-bound aircraft on 15 October, is the Swiss carrier's third such incident since July.
In response, Swiss withdrew the A220 fleet from service while it carried out inspections.
Airbus says it "sincerely regrets this inconvenience" but says the first aircraft have already returned to service. It adds that it is providing "full support" to Pratt & Whitney and investigating authorities.
The US National Transportation Safety Board is leading the probe into the Swiss engine failures.
Swiss became the first operator of the A220 – then known as the Bombardier CSeries – after taking delivery of the initial customer aircraft, a CS100, in mid-2016. The CS100 has been redesignated the A220-100.
All three of the Swiss engine incidents have involved the larger model – the A220-300, previously the CS300 – of which Swiss started taking delivery in mid-2017.
Ninety A220s had been delivered worldwide by the end of September this year, including 29 to Swiss, the largest operator of the type.
Delta Air Lines has 25, all the -100 variant, while Air Baltic has just completed delivery of its initial batch of 20 A220-300s.
Korean Air has 10 A220-300s while another six are evenly distributed between EgyptAir, Air Tanzania and lessor GTLK.
