9.G, my understanding of Operational Landing Distances (OLD) is that only a 15% margin (FAA) is applied; this is not equivalent to the factored landing distances discussed previously, instead more like the shorter Boeing ‘actual’ distances.
Although TALPA has been led by the FAA and US operators, EASA is taking an interest in the reporting matrix.
TALPA background - FAA conference 2006 -
Runway Condition Determination, Reporting, and Report Dissemination Workshop
A more recent update - EASA conference 2010 -
Workshop on Runway Friction and Aircraft Braking
Boeing and Airbus views are presented; Airbus provides good comparisons with EU OPS and FARs and a realistic view of operational landing distances (OLD).
Although Airbus support OLD, the concluding slides (23/25) notes many problems, not least introducing (
more) risk.
Also, if the 15% margin were retained by the FAA and the full factored distance by EASA, then there would not be a level playing field for the manufacturers amongst EU vs FAA operators. FAR operations could claim a shorter distance from an in-flight reassessment, but EU operators could not.
This also raises the issue that although OLD with 15% margin might be shown to be equivalent to current EU requirements for landing distance, it may not be equivalent in safety as OLD uses reverse thrust (generally not considered in certification).
With the current poor overrun safety statistics it might be foolhardy to increase the risks during landing operations.