MONTREAL - U.S. private equity firm Directional Aviation Capital is expanding its aerospace activities by leading a group that has agreed to buy Bombardier's Flexjet fractional business aircraft ownership service for US$185 million.

The new owners have also ordered up to 245 Bombardier aircraft in a deal whose value could reach some US$5.2 billion.

The order -- the largest in Flexjet's history -- includes a firm order for 85 business jets and 160 options for various Challenger and Learjet aircraft.

The firm order, valued at US$1.8 billion, at current list prices includes 25 Learjet 75, 30 composite Learjet 85, 20 Challenger 350 and 10 Challenger 605 jets.

Bombardier CEO Pierre Beaudoin says the sale of Flexjet after 18 years allows the Montreal-based aircraft manufacturer to focus on its core business.

Flexjet will be added to Directional's portfolio that includes Flight Options, Sentient Jet cards and Sentient Jet Charter. It also has other aviation investments, including Nextant Aerospace, Constant Aviation, Everest Fuel Management, Sojourn Aviation, Spinnaker Air and API.