With sales of its new CSeries jetliner failing to take off and a sinking share price, despite a multi-billion dollar government cash injection, the horizon is darkening for Bombardier.

Suddenly, the Canadian manufacturer's dream -- going head to head with the workhorses of the aviation market, the Airbus A320 and Boeing 737, in its first foray outside business and regional passenger aircraft into the category of medium-range, single-aisle jets -- is turning into a nightmare.

The first completely new aircraft design in the 100- to 150-seat category in more than 25 years was supposed to offer significant fuel savings over its rivals.

But a two-year delay in its development allowed both Airbus and Boeing to freshen up their respective lineups with the launch of the A320neo and 737 Max, which are similar to their old planes but with new fuel-saving engines.

The first neo rolled off the assembly line in January, while Boeing expects to deliver its first Max in late 2017.

Bombardier is expected to make the first delivery of its CSeries to Lufthansa subsidiary Swiss in the coming months. But it can no longer boast of 20 percent fuel savings over competitors. At best, the CSeries is 10 percent more fuel efficient than the neo or Max, Bombardier has acknowledged.

Considering that airlines would also have to shell out money to train pilots on the new aircraft, that makes the CSeries less attractive to potential buyers.

Meanwhile, development costs have soared to US$5.4 billion, nearly double the amount Bombardier had budgeted.

The CSeries "was an attractive purchase when oil cost $120 a barrel, but at $29, the argument for fuel savings falls apart," Mehran Ebrahimi, an aeronautics professor at the University of Quebec in Montreal (UQAM) told AFP.

But the fact remains that the CSeries is "incredibly quiet," which is a welcome design improvement for people who live near an airport, commented Isabelle Dostaler, another aviation expert at Concordia University in Montreal.

Ebrahimi noted that Airbus and Boeing are trying to undercut Bombardier and hold onto their duopoly in this segment by offering deep discounts on their new jetliners.

And it appears to be working. Airbus has received 4,500 orders for its neo, while Bombardier has received no new orders for its CSeries since September 2014, after landing 243 orders during its development stage.

- Keeping Bombardier in Canada -

Faced with these difficulties, Bombardier asked for and received US$2.5 billion from the government of Quebec province, where it is based, to get its CSeries program off the ground, giving up a 49.5 percent stake in the CSeries program and 30 percent of its rail unit in exchange.

Since receiving the cash injection, Bombardier's stock has fallen 40 percent to a record low of Can$0.72 before bouncing back slightly to close Friday in Toronto at Can$0.81. (North American markets were closed Monday).

The company has also asked Ottawa to contribute, but Prime Minister Justin Trudeau's Liberals have reportedly been hesitant to give public funds to a family-controlled firm.

Heirs of founder Joseph-Armand Bombardier hold a small stake in the company but control its board through a majority of voting shares.

"Has the Bombardier family taken such good decisions over the past decade? Not really," Dostaler said.

"Just because you have a blood tie doesn't necessarily mean you share your grandfather's business acumen," she said of Pierre Beaudoin, grandson of Joseph-Armand Bombardier.

Beaudoin stepped aside as chief executive of the world's third or fourth largest aircraft manufacturer last year, and was replaced by outsider Alain Bellemare, who once worked for Pratt & Whitney, the supplier of engines for the new CSeries.

Beaudoin meanwhile took on a new role as executive chairman of the board.

"The problem wasn't Mr. Beaudoin," said Mehran Ebrahimi. "The problem is a lack of strategy for Canada's aeronautics sector," which remains underfinanced compared to rivals that receive generous outlays of public funds.

"Take out the (Canadian nationalist) Beaudoin family, and with the Canadian dollar at a recent low, you risk having this Canadian corporate icon being picked up by a foreign buyer at a bargain," he said.

Bombardier started off building snowmobiles in 1942 and grew into a multinational with rail and aircraft divisions. It has 70,000 employees worldwide, including 24,000 in Canada.

It will release its 2015 financial results Wednesday.