The plane could eventually rival Airbus' A320 and Boeing's 737 in the short- and medium-haul market. It has signed a deal with budget carrier Ryanair for aircraft development. Brazil's Embraer, the market leader in the regional jet market, sees good chances of firm orders from U.S. carrier Delta Air Lines. Our expectation is that Delta decides about all this in October ... they are in talks with everyone, Paulo Cesar de Souza e Silva, who heads Embraer's commercial aviation unit, said in an interview with Reuters at the show. Canada's Bombardier has announced a provisional order for up to 30 of its CSeries aircaft worth close to $2 billion (Additional reporting by Victoria Bryan, Gilles Guillaume, Kyle Peterson, Rhys Jones, John Irish, Tim Hepher; Writing by John Irish and Jane Merriman; editing by Sophie Walker and Erica Billingham)