I fly the 737-800 on FSX and normally use the ILS to land, can anyone please tell me what the the Backcourse button does and when should it be used.
Thanks in advance.
Backcourse is a non-precision approach using the localiser of the opposite end of the runway. For example, runway 09 at an airport has an ILS for aircraft to execute precision approaches. However, runway 27 (i.e. opposite end) doesn't have it's own ILS rather it uses the localiser (lateral navigation) as a means of guiding an aircraft. Notice it is a non-precision approach because the GS (glideslope) is rarely included in a backcourse approach.
Remember though, because you are using the back signal of the opposite end ILS, you'll have to reverse sense in your head when looking at the display - i.e. left is right and right is left.