SINGAPORE—Bombardier and Airbus could have a C Series final assembly line in the U.S. up and running within a year of a go-ahead, but it remains undecided whether CS100s ordered by Delta Air Lines will be produced there or in Canada, a senior Bombardier executive said. While the two airframers are limited in what information they can share before Airbus’ deal to acquire a controlling stake in the C Series program wins regulatory approval, integration with Airbus is now the ...