TORONTO (AP) -- Bombardier is delaying again the in-service launch of its much-touted CSeries single-aisle airline.

The world's third-largest maker of civilian commercial aircraft had said the plane would be ready for service later this year but now says it will be the second half of 2015.

Bombardier says the larger CS300 will enter service six months after that.

Bombardier says the flight test phase will require more time than originally anticipated.

The Montreal-based company has said it hopes to capture half the global market of the 100-to-149-seat planes, and has marketed the plane as being 20% more fuel-efficient than the comparable Airbus A320 and Boeing 737 family of aircraft.

Bombardier has 198 firm orders. The delay was announced shortly after Bombardier Aerospace signed a deal with SaudiGulf Airlines for 16 CS300s.