Bombardier Inc. has secured a letter of intent from EgyptAir for the purchase of up to 24 of the Montreal-based company's larger C Series aircraft, the CS300.

The transportation giant announced the news at the Dubai Airshow, where the company said the deal is a firm order for 12 of the jets, plus an option to buy an additional 12.

The 130- to 160-seat jet has a list price of $89.5 million US, so buying 12 of them would cost almost $1.1 billion on paper, although Egypt's national airline would likely have paid less than that.

It's the second order for the planes since Bombardier signed a deal with Airbus last month to give half its C Series business to Airbus, to take advantage of their marketing and manufacturing clout.

That move came after U.S. rival Boeing successfully managed to get tariffs of up to 300 per cent imposed on Bombardier's jets sold in the U.S.

While the company announced a "letter of intent" from an unnamed European airline earlier this month to buy 31 of the planes, Bombardier hasn't landed a firm order for its jets in calendar 2017 and is facing a growing backlog on delivering the ones it has already sold.

The last firm C Series order was for two aircraft from Tanzania in December 2016, TD Bank analysts Tim James and Shawn Levine noted in a report on the company Tuesday. Prior to that, the last firm order for the jets was Air Canada's call for 45 aircraft in June 2016.

To date, the company's biggest order came in April 2016 from Delta for 75 jets, the deal that prompted the trade complaint from Boeing in the first place.