At the end of the third quarter, Gulfstream was ahead of Montreal-based Bombardier, which has been the global leader each year since 2005.
Bombardier delivered 36 aircraft valued at US$1.38 billion in the quarter, compared with Gulfstream's 38 planes valued at US$1.96 billion, the General Aviation Manufacturers Association says.
After nine months, Bombardier trailed Gulfstream in terms of sales value (US$4.48 billion vs US$5.3 billion) although Bombardier was ahead in terms of units sold (120 planes vs. 103).
The introduction of the Gulfstream 650 helped the U.S. manufacturer more than double both the number of planes it sold and the value of shipments recorded in the third quarter.
Bombardier (TSX:BBD.B) said it expects a stronger fourth quarter after enduring some challenges in registering and delivering business jets due to the U.S. government shutdown.
The company has forecast that it will deliver 245 planes, including 190 business jets this year. That means it has to deliver 90 aircraft, including 20 business jets in the fourth quarter.
"We do believe that top spot is still within our reach," spokeswoman Annie Cossette said in an interview.
She said the company had anticipated variations in revenues and market share once Gulfstream began G650 deliveries. Deliveries of its Learjet 70/75 recently started to move and interest is growing for ultra-long-range planes.
The Global 7000 is slated to enter into service in 2016 followed a year later by the Global 8000. Also, its new Learjet 85 is expected to have its first flight this year and enter into service by next summer.
"Of course everybody wants to be No. 1... For us, the most important thing is to see our product portfolio being well-received and well-positioned in the market."
David Tyerman of Canaccord Genuity said he doesn't care which company ultimately claims top billing in terms of annual sales.
"An investor should really care about profit. Sales figures mean nothing if you don't make any money on it and clearly Bombardier didn't make enough profit in the third quarter," he said.
He expects many more aircraft deliveries in the fourth quarter that should boost full-year profits.
"Although it won't be a great year for aerospace and the business jet business, it will probably look a lot better than where it is right now."
Overall industry shipments of business jets were relatively flat in the quarter at 138 planes, but were down 2.1 per cent to 421 planes over nine months.
Since the economic downturn, larger business jets such as Bombardier's Global 5000/6000 and Challenger 300 have performed better than smaller aircraft such as Bombardier's Learjets.
On Thursday, Bombardier's company's stock fell by more than 10 per cent after it reported weaker-than-anticipated third-quarter results in its aerospace and railway divisions amid low aircraft deliveries and "execution" issues for new large rail contracts.
Analysts said the magnitude of the stock selloff was "unwarranted" but Bombardier's shares closed down another 3.38 per cent or 16 cents to C$4.58 in Friday trading on the Toronto Stock Exchange.