3000/10 giving a three degree slope is an easy approximation. But it’s not exactly three degrees - is a couple of hundred feet out. (Actually 3182’ over 10nm). Applying this approximation to FPA calcs gives the 0.2 difference between our answers.
Remember high school trig? SOH CAH TOA
In my earlier post you have a triangle of 2280 (opposite) and 6.3*6072 (adjacent).
that’s 3.41 degrees. Plenty of online trig calculators to help visualise.
And to clarify the 10% quick rule is say: FAF = 2000. FAF Corrected =2280.
2280/2000=1.14. Ie 14% higher. Times this by the chart FPA.
1.14*3= 3.42 degrees. Closer to the actual FPA than you can set of the dial.
Last edited by compressor stall; 27th Mar 2020 at 21:23.