MONTREAL, Canada - Bombardier's CSeries aircraft program reached a major milestone Saturday with the maiden flight of the CS300 airliner.

The technologically advanced CSeries range is intended to provide operators with an all-new family of single-aisle mainline jets specifically designed for the 100- to 149-seat market segment.

The new CS300 model departed Montreal-Mirabel International Airport at 11:00 EST and returned at 15:58 EST, having reached an altitude of 41,000-feet (12,500m) and a speed of 255-knots (470 km/h).

Some2,000 Bombardier employees, board members, partners, suppliers and customers braved frigid temperatures to witness the flight at Bombardier's Mirabel, Quebec facility.

"Our CSeries aircraft program is progressing well, with results from testing as expected or better," said Rob Dewar, Vice President, CSeries Program. "The CS300 airliner will now join the five CS100 aircraft flight test vehicles that have amassed more than 1,000 flight test hours to date."

Dewar added that the aircraft manufacturer was confident the CS100 airliner would be certified in the second half of 2015, followed closely by entry-into-service. The CS300 airliner is expected to follow about six months later.

"It was a thrill to see the first CS300 aircraft take to the skies for the first time and I heartily congratulate our teams for this achievement," said Mike Arcamone, President, Bombardier Commercial Aircraft. "We continue to see increased interest from all over the world and as our performance targets are validated, we expect the enthusiasm for the CSeries family of aircraft to grow even more."

Bombardier is marketing the CS300 aircraft as offering the best seat-mile cost in its category, and claim it is the most profitable solution for mid-sized markets.

Carrying up to 150 passengers per flight, the airliner is designed for short-haul to medium-haul transcontinental markets.