Originally Posted by
sigler
Are you asking about a failure before take off, as in the airplane is dispatched with a MEL item that affects landing performance? If so, multiply your total RLD (4312’ in your example) by whatever factor your MEL tells you to. Once in flight, or if you have a failure in flight, use whatever means your company gives you to calculate your in-flight landing distance, or the QRH. Forget about the numbers on your release, they no longer apply once you’re airborne.
No.. no MEL. we’re in flight. All is good. ACARS says runway is 8500’ long, so I guess we need 5100’ to stop. But given our weight, winds, etc.. it says we can conceivable stop in 3500’. Now we’re descending and we get a caution message and run the QRH. It says add 20% to the landing distance. Am I adding 20% to 3500 or 5100? (I know either way I can land.. but I want to be right about this)
Question 2: same scenario but ACARS went no-comm and I’m relying on the release. It says dry runway at this weight requires 5250, let’s say. Do I add 20% to that? If that’s the case then I should be adding 20% to the higher number w/ ACARS, right?