The decision came after a flight from London to Geneva was rerouted to Paris early Tuesday due to “a new incident raising questions about the engine” on the model, Swiss said in a statement sent to AFP.
The airline counts 29 of the planes, initially known as the Bombardier C Series, in its fleet.
They have experienced a number of recent engine-linked incidents, with Tuesday's event constituting the eighth in just over a year, Swiss public broadcaster RTS reported, citing the Aviation Herald.
The news came as France's investigation and analysis bureau BEA on Tuesday sent out a call for volunteers to help find pieces of an engine dropped by a Swiss-flown Airbus A220 over Yonne in July.
And the Federal Aviation Administration in the US last month issued a so-called “Airworthiness Directive” requiring inspections of the Pratt & Whitney engines that equip the A220 following the event in July and a similar incident in September.
Swiss said the decision to ground the flights would take effect immediately and that the planes would not be permitted to take to the skies again until they had undergone “adequate inspection”, but did not provide an expected timeline.
The airline said it was working closely with Airbus and with engine maker Pratt & Whitney to get to the bottom of the issue.
“Swiss takes these incidents very seriously,” it said, stressing that “the security of our clients and our crew is our absolute top priority.”
It acknowledged that “numerous flights will need to be cancelled”.
“We sincerely regret the complications that this will cause our passengers,” it said, adding that it would help affected clients to reschedule their reservations or find alternative solutions.
Airbus also voiced deep regret at the “impediment for our customer and its passengers”.
It said it and the engine manufacturer were supporting Swiss “to minimise disruption to their operations.”