Since the Bombardier C Series aircraft are blocked from entering the US market by punitive tariffs, the issue is still discussed in different platforms.

The Canadian aircraft manufacturer now receives backing from Europe. The EU Commission criticizes blatant deficits as well as methodological and legal shortcomings in the procedure.

The Delta hubs New York and Los Angeles have to wait for the first CS100, as 75 deliveries to Delta are on hold because of US government punitive tariffs. The United States and Boeing accuse Bombardier of unfair competition.

The US government justifies the 300 percent punitive tariffs against the C Series with anti-competitive state aid to the program by Canadian government.

"The investigation has blatant deficits, both in terms of their methodology as well as the conclusions drawn," says the EU Commission in a "Case Letter" to US Secretary of State Wilbur Ross. "It is doubtful that the methodology is compatible with the rules of the WTO," the letter also says.

The US government justifies the 300 percent punitive tariffs against the C Series with anti-competitive state aid to the program and dumping prices that secured Bombardier's contract with Delta.

A finding of price dumping implies actual imports. But they have not been done yet, according to a passage in the Commission's paper. "Bombardier gets into a "Kafkaesque situation" if the corporation is to submit to discharge documents for something that does not exist," the letter continues.

Bombardier partners with Airbus

The new C Series airliners from Canadian manufacturer will be marketed by Airbus in the future. The European aircraft manufacturer threaded in October a majority program participation and wants to manufacture the C Series also in its US plant Mobile.

The cooperation with Airbus may deepen to put Bombardier in a new role as a supplier. Bombardier produces wings for the CS100 and CS300 at its Belfast plant and could also produce components for Airbus in Northern Ireland, said Fred Cromer, chief of Bombardier's aviation division, at the Dubai Airshow.