Hi!!! I am a newbie pilot. I saw in Boeing 737-400 cheklist for FS the FL240, FL180 and FL120 expressions. What is this? Thanks!Richard Lemos

The FL stands for Flight Level and is measured in hundreds of feet. So FL240 = 24,000 ft. In the US, FL is used beginning at FL180 (and the barometric pressure is set to 29.92 inches). Below that you use the full altitude numbers.This should all be covered in the FSX Learning Center.Phill

Thanks Phill. Then, when the checklist says "Descent speed to FL180 - .65 mach", I need to reduce speed to .65 to down to 18,000 ft, right?>The FL stands for Flight Level and is measured in hundreds of>feet. So FL240 = 24,000 ft. In the US, FL is used beginning>at FL180 (and the barometric pressure is set to 29.92 inches).>Below that you use the full altitude numbers.

That's correct.Phill