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A blazing set of Cat3 touchdown lights is superior to just 15m centre lights. We need the 15m centre lights because for some part of the takeoff you will use them. That's why they are needed as a basic minimum. Let me put it another way. Where in EU-OPS does it say you must commence the takeoff from the first 15m centre light ? It says you commence takeoff when you have established a visual cue of 90 m
Hang on, where are the touch down lights in relation to the displaced threshold? You need the 15m lights and the 90m visual segment and etc.. Not just one, or two or whatever you feel like. Where in EUOPS does it say you only need the 90m segment?
You base your performance on a formally declared TODA which is based on particular published holding points. In many cases that has nothing to do with the beginning of the runway threshold hence you would bust your performance with no way to recalculate.
It's called EFB. Runway shortening XXXm from the beginning or the end. Calculate.