The airline has been forced to remove 16 Boeing 737s from service after a severe storm at its Calgary hub on 5 August. 

The carrier said it needed to make “proactive cancellations for the foreseeable future”, largely affecting domestic services, with repairs and inspections of damaged aircraft taking “several weeks”.

WestJet added: “Through the proactive issuance of cancellations across the month of August, WestJet will aim to minimise disruption, secure re-accommodation options for those impacted wherever possible, while providing guests with timely communication and options to appropriately manage their own travel in advance. 

“WestJet is currently cancelling an average of 50 flights per day, however anticipates fewer cancellations will be required as aircraft are returned to service in a phased approach.”

The carrier said it was “currently experiencing very high volumes for phone, email and social media support channels” for rebookings.

Diederik Pen, WestJet Airlines president and chief operating officer, WestJet Group, said: “Our operations teams have travelled from across our network to Calgary and Toronto, where they are working around the clock to return our fleet to its full capacity. 

“We thank everyone for their patience and support and are committed to doing everything in our power to minimise the impact on our guests and our people.”   

The hailstorm left another two aircraft with minor damage that have since returned to service. Another four were moved to a hangar for protection while nine in the air were diverted.

It comes after the transatlantic carrier WestJet launched a new route between Gatwick and St John’s in Canada in May.

It will operate flights three times a week on Sundays, Wednesdays and Fridays until 25 October.