American Airlines Group Inc. said Thursday it has signed deals to buy 90 jets, including 30 Bombardier CRJ900 aircraft and 60 Embraer E175 planes, with a total value of $3.92 billion. The planes have 76 seats.

The order with Sao Paulo, Brazil-based Embraer S.A. was about $2.5 billion based on the list price. The order with Bombardier Inc., of Montreal, Canada, was valued at about $1.42 billion.

American, which closed its merger with US Airways Group on Monday, said the regional jets will provide improved economics and replace smaller, less fuel efficient 50-seat regional aircraft.

American took options for as many as 40 more Bombardier aircraft and up to 90 more Embraer planes.

The CRJs will be flown by US Airways commuter subsidiary, PSA Airlines. The Embraer E175s will be operated by the American Eagle regional unit or US Airways Express.

The combined American is the dominant carrier at Philadelphia International Airport.