Originally Posted by
Paul Lupp
Curious to know how long the "landing approach" has to be... for example if you are flying west to east, but have to land in a westward direction, how far past the airport is it normal to fly before turning round and heading in to land? (This is for passenger planes, 777, A380 etc). Are there guidelines for descent altitude versus distance from airport?
Altitude vs distance for an instrument runway is a function of the ILS glideslope angle. That's typically 3 degrees, equivalent to just over 300 feet per nautical mile.
Airlines typically require approaches to be stabilised by 1000', so that's a bit over 3 nm from the runway, although aircraft will usually join the ILS farther out than that.
https://www.skybrary.aero/index.php/Stabilised_Approach