Hi,
I am not familiar with this drift-down table. So this just a simple guess:
The MCT during drift-down with engine anti-ice ON is superior than the MCT with total anti-ice ON (IF total anti-ice means engine and wing anti-ice, I guess the other electrical anti-ice are always ON like Pitot..), and MAY BE that's why the distance and time to reach level-off INCREASES SIGNIFICANTLY (the same reasoning for the MCT with engine anti-ice OFF compared to the MCT with engine anti-ce ON). The raison is wing anti-ice represents an important load for engine compared to the engine-anti-ice.
If what I said is true, the fuel consumption with total anti-ice ON should be superior than the fuel consumption with engine anti-ice ON. But infortunately
it is the same on both cases (+ 15 % according to the table). Sorry Sabenaboy I cannot help you
Can someone explain me why the fuel consumption is the same (+ 15 %) on both cases: engine anti-ice ON & total anti-ice ON?
Thank you.
Best regards.