The Learjet 40 (LJ40) is a light business jet produced by Bombardier Aerospace.

[2] The Learjet 40XR is an upgraded version introduced in October, 2004, offering higher takeoff weights, faster cruise speeds and faster time-to-climb rates as compared to the LJ40.

The increases are due to the upgrading of the engines to the TFE731-20BR configuration.

LJ40 owners can upgrade their aircraft through the incorporation of several service bulletins.

[3] Data from Jane's All the World's Aircraft 2004–2005[4]General characteristics Performance