Originally Posted by
Capn Bloggs
Given the thread is about an aeroplane that ran off the end in the wet, your choosing of the desired braking "method" to increase the buffer is irrelevant. Obviously, we're talking about a max-braking landing with only 15% buffer.
We are not obviously talking about a max effort stop with a 15% margin because the crew concerned didn’t carry out any landing distance calculations. This whole line of conversation has come about because you stated that you don’t feel that 15% is an adequate margin on assessed landing performance and prefer to rely on 67/92%.
IFLD figures are there to provide guidance on the actual level of performance available given the conditions and take account of runway condition. So the braking method chosen is not irrelevant, one could calculate the distance required with autobrake 2/low and find that even on a contaminated runway there is sufficient LDA with the 15% margin applied.