General Navigation - Departure
Hi. I am having a problem working out this, please tell me where I'm wrong.
Q: What is the distance between 00500W and 01000E at a latitude of 35°S?
So I have to find the East-West distance between 500' W of Prime Meridian and 1000'E of PM.
That adds up to 1500' difference between the two meridians.
Departure = D Long cos Lat
1500 cos 35 = 1228.72 nm
Ok that was my working, here's the brief explanation in the book:
D Long = 15 x 60 = 900’
900 cos 35 = 900 x .819
737 nm
Where did that 15degrees come from? Isn't that supposed to be 25 (1500' / 60 = 25 )
Please enlighten me.
Thanks.