The BMP texture is 24-bit and REQUIRES conversion to DXT3 or, preferably, DXT1 format using DXT2BMP before being used in FS9. DXT1 can be used because there is no alpha channel on HTAI Learjet 35 textures.

Both textures need to be renamed ailear35.xxx (dds or bmp according to your sim). I add the operator and notional base to the name for my own filing system for these textures. I might add them into the sim many months later, and need to remember the operator and base.