In this regard, EU-OPS 1 is sufficiently similar to JAR-OPS 1 for an interpretation to be the same; note ‘interpretation’.
There is little regulatory guidance (EASA) on how the dispatch / pre-landing (in-flight) assessment of landing distance should be equated. However, recent UK CAA advice clearly outlines their interpretation:-
“Before commencing an approach, the commander is required to ensure that a safe approach and landing can be made given the updated meteorological and runway surface condition (see EU-OPS 1.400).
The operator is required to demonstrate that it can ensure safe operations, and by applying the same additional safety margin to the in-flight performance assessment as to the dispatch assessment demonstrates an equivalent level of safety.”
The quote is taken from Appendix 1 of
Safety Notice SN–2011/016, Operations on Contaminated Runways.
Although the document is titled ‘contaminated’ it provides a wide range of information of landing performance issues and safety, with obvious focus on operations on contaminated runway, which are allowed in EU-OPS (and CS-25).
Thus the in-flight decision to land should be based on the same landing distance factors as for dispatch.