An Air Canada Boeing 787 plane that was flying across the Atlantic from London to Toronto instead landed in Dublin after a crack in its windshield was noticed mid-flight. It was the second time in a month that an AirCan Dreamliner was diverted due to a window crack.

Air Canada confirmed to Business Insider that flight 857 was diverted to Dublin “due to a cracked Captain’s side window” while there were 254 passengers on board.

The plane was about one hour into its journey Saturday and had already passed Ireland when the plane turned around, the aviation-news website Simple Flying reported.

The plane, a 787-8 model, landed in Dublin about 55 minutes after the crew reported the incident, according to Simple Flying.

Data from the flight-tracking website FlightRadar24 shows the plane’s abrupt U-turn upon finding the crack.

The passengers were put on a different plane to continue on to Toronto the following day, Air Canada told Business Insider. It said the passengers “were put in hotels for the night.”

It also said that the plane, with a tail number of C-GHQY, was repaired and has returned to service.

Other Boeing 787 planes have experienced cracked windshields, including a Jetstar Boeing 787-8 plane that was diverted to Melbourne, Australia, while en route to Indonesia in September.

Boeing did not immediately respond to a request for comment from Business Insider about the Air Canada flight and the broader subject of cracked windshields on 787 aircraft.

The incidents have also previously involved Air Canada. In September, a flight from Shanghai to Vancouver was diverted to Tokyo after a crack appeared.

Air Canada said after that flight that the landing was precautionary because the windows had two panes of glass.

Boeing is also dealing with a separate cracking problem in its 737 plane model, in which cracks have appeared on an area called the pickle fork, which connects the plane body, wing structure, and landing gear.

This has led some airlines, like Ryanair and Qantas, to ground some of the planes after they found cracks during inspections.”