The head of Boeing's commercial airline business said at the launch of the Paris Air Show on Monday that he was hopeful the depressed aviation sector could bounce back in 2010.
"There is no certainty. But it does feel to us that there are reasons to hope that the recovery will begin next year," Scott Carson told a press conference as the week-long event kicked off at Le Bourget outside Paris.
"It feels to me that we may have reached the bottom," he said.
Dismal financial prospects for the airline industry and the puzzling crash of an Air France Airbus have cast a pall over the 100th edition of the Paris show, with industry executives foreseeing few blockbuster orders.
Carson said the swine flu health scare had also hit airlines hard.
He also poured cold water on speculation the US planemaker's new 787 Dreamliner could make its test-flight to coincide with the airshow.
"If you expect the fly during the airshow, you will be disappointed," he told reporters, although he said Boeing still planned the flight to take place by the end of June.
Like its European rival Airbus, which is battling major delays to its A400M military transporter, Boeing has encountered development problems and delays with the long-haul, fuel-efficient 787.