Shares of Brazil's Embraer posted their biggest intraday loss in nearly five months on Thursday, falling 7 percent after rival jet maker Bombardier won a major order from Delta Air Lines.
Delta placed a firm order for 40 Bombardier NextGen jets on Thursday, with the option to buy another 30, in a deal valued at up to USD$3.29 billion.
With that, Embraer lost its best bet for a big order this year, leaving the world's biggest maker of regional jets with fewer options to rebuild its shrinking order backlog and keep up the current pace of production.
"While we are disappointed in this decision, we have confidence that our aircraft provide the best overall business proposition for our customers," Embraer said in a statement. "We are confident that we are well positioned for upcoming competitions."
Without new commercial jet orders by early 2013, chief executive Frederico Curado said last month that Embraer would not be able to maintain stable E-Jet output next year, as its order backlog hit a six-year low on thin demand.
Curado said in September that Delta was the airline most likely to make a big regional jet order this year.
Shares of Embraer were down 3.3 percent at 13.10 reais after falling as low as 12.55 reais earlier in the session.