Originally Posted by
beetlehog
A wise Captain once told me "son, if you don't make that touchdown zone, all those numbers you just pulled out of your backside don't mean a darn thing!"
In most if not all of the airplanes I've been typed on, the landing distance was predicated on touching down 1,500 feet from the threshold (manual landing). An autoland calculation was different.
For example, a runway length of 9,500 ft and the landing distance required considering the weather conditions is 7,500 ft. If you touched down at the 2,500 point (still inside the touchdown zone) you're going to be short 500 feet.
Make sense?
Originally Posted by
FXLAX
Also, as a reminder, the APS does add 1500 feet to account for landing in the touchdown zone.
I don't think the APS "adds" 1,500 feet to account for landing in the touchdown zone. The APS landing distances are based on a touchdown 1,500 ft from the threshold. If you land beyond that 1,500 feet down, you must ensure your touchdown point and the landing distance are less than the runway available.