Originally Posted by
IO540
I think LH2 has the right answer, but the real Q is
what is the exam paper looking for?
To be practical, the Winds Aloft forecasts are almost never right. Errors of 30-50% in the wind speed are pretty common, especially at the low levels (say 2000ft) at which GA pilots are asked to demonstrate their dead reckoning prowess.
Averaging the direction (heading) figure is also the right thing to do, if the variation is small, say 30 degrees. The problem is if one spot shows 090 and the other one shows 270. The average is then 180
What this tells you is that there is a frontal system lying between the two, or something like that, and you need to apply different winds to different segments of the route.
thanks for all your replies, most helpful. I have passed the exam bt wanted to know the "real world" way of doing it which is going to actually help my flying and navigation