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GeeEss created the topic: Exercise 4.1 of performance book

Hi all,

I don't understand how we arrive at the answer for question 3, exercise 4.1

We're asked to find the rate of climb given the elevation, QNH, OAT and weight of the aircraft.

Q3 says, At sea level, QNH 1010, OAT +35 and Gross weight 2725KGS, what is the rate of climb with reference to the table in the supplement on p.14

So the density height I calculated the same as the answers on page 124 of the book, but then how you've averaged and interpolated the figured I don't understand.

The answer says 1600 + 1500 + 2250 + 2100 / 4

Can someone help me understand where those numbers came from please?

bobtait replied the topic: Exercise 4.1 of performance book

The density height you calculated is half way between the listed heights ( zero and 5000) and half way between the listed weights (2950 and 2400}. So it's a four-way interpolation.