FW, at the `fix`/step,the a/c flies at an indicated altitude of 5000ft.Another a/c is vectored to 4000 ft in the same area.
The higher a/c is at a true altiude of 4700 ft under the conditions.
The lower aircraft is at a true alt of (4x4x15=240)=3760ft..difference ,940ft..
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Last edited by sycamore; 23rd Sep 2017 at 19:43.
Reason: brainfade