One important thing I keep noticing people doing. On TOPCAT you cannot select the checkbox that says allow combination of both derate and assumed temp. It doesn’t work like that in captain sim. In CS if you select a fixed derate, “TO1” “TO2”, then you select a temperature, the derate is instantly cancelled and the EPR will be considering temperate only. Just like the real plane.

Nevertheless, there is an issue with their calculation and I hope they can fix it.

In my attachment, that box I circled should be UNCHECKED

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