Porter Airlines' order for up to 30 Bombardier CS100 aircraft, which is worth up to $2.29 billion, is welcome news for Bombardier.
It means the airframer has gained another customer that has chosen the aircraft type for flying at urban airports, which have strict noise and emissions regulations.
However, while the airline clearly wants to use the CS100's range of 2,950nm (5,460km) as a foundation for growth into destinations such as Los Angeles and the Caribbean, the order is conditional on Porter gaining key approvals before it can fly it out of Billy Bishop Toronto City airport.
Porter must work with the Canadian government, the city of Toronto and the Toronto Port Authority to permit the type to fly in and out of its hub at Billy Bishop, which does not permit commercial jets now. The carrier is hoping for an approval in the next six months, says chief executive Robert Deluce, who says approval would "open up two-way traffic that will benefit everyone".
In addition to convincing these authorities that the CSeries is quiet enough and environmentally suitable, Porter is requesting a 168m extension into the water at each end of the main runway to accommodate the CS100. The aircraft needs at least 4,000ft (1,220m) to take off and 4,400ft to land. Deluce said the extension is "pretty modest".
Lufthansa's Swiss subsidiary faces a similar situation. The carrier has made a firm order for 30 CS100s and plans to fly them out of London City airport, which proposes to build aircraft stands capable of supporting an aircraft the size of the CS100. The airport plans to accommodate the CSeries without extending its runway.
If Porter can secure the approvals, the orders would be added to Bombardier's CSeries order book, which stood at 148 firm orders for the CS100 and CS300 types at the end of 2012. Overall, the airframer has 382 commitments for the CSeries, and the Porter order shows the aircraft appeals to carriers wanting to reach urban airport markets that have been virtually untouched by larger narrowbody aircraft.