Bombardier's long-delayed CSeries aircraft program received a boost on Monday, when the company announced two tentative orders for a total of up to 24 jets worth nearly $1.6 billion.

Montreal-based Bombardier said it had signed an agreement with Chinese carrier Zhejiang Loong Airlines for 20 of its CSeries jetliners.

The order for the CS100 version of the jets, which comes of the first day of the Farnborough International Airshow in England, would be worth roughly $1.28 billion, if confirmed, Bombardier said.

Separately, the Canadian aircraft and train manufacturer said Petra Airlines of Jordan had also signed a letter of intent to buy up to four CS100 and CS300 planes. If confirmed, the order would include two CS100 aircraft and two options for CS300 aircraft worth a total of about $298 million.

The tentative orders come just two days after Falko Regional Aircraft, a lessor based in Britain, signed two letters of intent to buy up to 24 CS100 jets. The tentative orders were the first new CSeries orders announced since the first quarter.

Bombardier is hoping to crack the lucrative 100- to 149-seat jet market with its CSeries aircraft. That segment of the market is currently dominated by industry giants, Boeing Co and Airbus Group.

But the CSeries, which Bombardier touts as having superior fuel and operating efficiencies, has faced a myriad of obstacles including multiple delays for the multibillion-dollar program. Most recently, engine problems have grounded the test planes.

Expectations around whether Bombardier would be able to win any orders for the aircraft at Farnborough have been muted, as the CSeries planes are not making an appearance at the world's largest aerospace event. - Reuters