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Gday guys,
Perhaps someone can clear this up for me.
Going through the CPL Performance book and I've come across a question which says if the temperature is ISA minus 10. What's the difference between ISA MINUS 10 and ISA deviation when applied to the question?
I'm unfamiliar with the terminology the book has the answers laid out that isa minus 10 is placed in the deviation portion of the flow chart so I'm confused.
There is no difference between ISA -10 and an ISA deviation of -10. They both mean the same. For example, the ISA temperature at 2000 feet is 11 degrees. If the actual temperature was 1 degree it would be 10 degrees colder that ISA. We could describe that as ISA -10, or we could simply say that the ISA deviation at that moment is -10.
Perfect I understand now 😉 thanks for your help Bob!