Two US lawmakers have written the head of the US International Trade Commission to express support for Bombardier in that company's trade dispute with Boeing.

The letters from Alabama congressman Bradley Byrne and Kansas senator Jerry Moran – both Republicans – come days before four trade commissioners will vote on whether Bombardier's sale of CS100s to Delta Air Lines in 2016 caused harm to Boeing.

The ITC has scheduled the vote, which stands to affect four of the world's leading aircraft manufacturers, for 14:00 local time on 25 January in Washington DC. The trade body may, however, postpone the vote due to the recent US government shutdown, says the ITC.

If the commission decides that the deal did harm Boeing, the Bombardier CSeries would be subject to a 292% import tariff already set by the US Department of Commerce.

"This trade enforcement action would ultimately serve no other purpose than to take work away from US suppliers and quash thousands of US jobs, ultimately hurting the greater US aerospace industry," writes congressman Byrne in a 19 January letter to ITC chair Rhonda K. Schmidtlein.

"I am writing to underscore… the critical need for your deliberations to consider interests of the US aerospace industry as a whole," adds Byrne, who represents the district that includes Mobile, where Bombardier and Airbus are working to open a CSeries final assembly line.

His letter says the CSeries programme will support 22,700 jobs with US companies and generate $30 billion for US suppliers of components like engines, avionics, fuel systems and braking systems.

Boeing, which has some 140,000 US-based employees, dismisses the argument that a ruling against Bombardier would harm the US industry.

“The driving force of this trade case has always been a desire to ensure fair competition in the aerospace industry. This week’s vote by the ITC is an opportunity to restore a level playing field and recommit to the global trading rules we have all agreed to," Boeing tells FlightGlobal.

Kansas senator Moran's letter to commissioner Schmidtlein highlights articles that address Boeing's recently-reported desire to acquire a major stake in Brazilian aircraft manufacturer Embraer.

The articles cited by Moran present the argument that Boeing seeks to acquire Embraer because Embraer, unlike Boeing, makes aircraft that compete with CSeries. The articles also present the view Boeing's interest in Embraer increased when news broke that Airbus intends to acquire majority ownership of CSeries.

"The articles raise concerns about Boeing's intentions with its petition to the ITC and its motivations for trying to acquire Embraer, which manufactures an aircraft that competes directly with Bombardier CSeries," says Moran's letter.

Wichita, Kansas is home to Bombardier's Learjet division, and Bombardier has conducted CSeries test flights in the city.

Boeing's trade petition rests on the argument that the 737-700 and 737 Max 7 compete with CS100, and allegations that Bombardier's low-ball sales prices harmed 737 sales.

Boeing has repeatedly insisted that its talks with Embraer have "absolutely no bearing on the ITC proceedings".

Boeing chief executive Dennis Muilenburg told The Seattle Times on 22 January that Airbus' CSeries move did "not at all" trigger Boeing's interest in Embraer.

"This was something we've been working on for a long time," he told the news outlet.

Airbus and Bombardier announced in October they were pursuing a deal under which Airbus would acquire a majority ownership of CSeries and open a CSeries final assembly site in Mobile, which would free the aircraft from potential import duties.

Source: Cirium Dashboard