Conform the regulations the landing distance required (LDR) for propeller engine aircraft needs to be within 70% of the landing distance available (LDA). The LDR for a wet runway needs to be multiplied by 1,15 (115% LDR). I was wondering whether this 'wet LDR' also needs to be within the 70% of the LDA to meet the regulations, or does it only need to be within the total LDA? And does the same count for contaminated runways?
Short Answer = Yes.
Long Answer = landing within 70% of the LDA rule is a HARD limitation. The runway's length does not change with the weather, so the 70% cannot be changed. But, of course, your A/C landing distance does change with weather. Thus, your 115% landing distance required must still be within the 70% LDA.
in practical application, not every landing you do will use 70% of the LDA, or even close to it (It's only a limitation, right?). In many cases, There's still lots of room for your 115% LDR to land safely within the 70% LDA.
Hope this helps!