American Airlines (AA, Dallas/Fort Worth) plans to retire forty-five B737-800s by the end of 2020 as it seeks to lower the average age of its narrowbody fleet, Bloomberg has reported.

The carrier plans to withdraw thirteen Boeing twinjets in 2019 and a further thirty-two units in 2020 at an average rate of three aircraft per month.

"It's strictly an age-based retirement at this point," American spokesman Josh Freed has said.

The planes will be more than offset by fifty Airbus A321neos and forty B737-8s which American Airlines plans to introduce by the end of 2020.

According to the ch-aviation fleets module, the Dallas/Fort Worth-based carrier currently operates a fleet of 304 B737-800s with a further final two aircraft on order. While the average age of the whole fleet of the type is 8.4 years, as many as seventy-six jets are older than 16 years.

The carrier is also planning to retire all remaining forty-five MD-80s, including ten MD-82s and thirty-five MD-83s, by the end of 2019. These aircraft could potentially be replaced with second-hand A319-100s, as previously reported.