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tomrob17
9th Aug 2013, 06:44
Hi All,

I am looking to sit my PPL Nav exam shortly and my studies so far haven't produced an answer to this query.

If I were going to fly from Swansea to Gloucester let's say and the main leg of the journey crossed the 2.5W Isogonal at it's mid-point what would I set the Magnetic Variation as for the leg. I would never be able to fly within .5 of a degree in real life but I understand the Nav exam demands accuracy :)

Thanks for your help!

mad_jock
9th Aug 2013, 09:36
You take it from the mid way point and it will work out right at the end. This is ok to do in the uk and lower latitudes. Near you get to the magnetic pole the more issues you will have.

tomrob17
9th Aug 2013, 12:43
That makes sense! Whichever occupies most of the leg I guess. Thanks for your help :ok:

FREDAcheck
9th Aug 2013, 19:41
I would never be able to fly within .5 of a degree in real life...
I'm glad you added that. I was beginning to think that this guy's got skills I could never aspire to :)

Runaway Gun
11th Aug 2013, 10:02
Just be sure to add it the correct way (or subtract) :ok:

mikehallam
11th Aug 2013, 16:51
Since 1969 this has stood me in good stead.

Take away any easterly magnetic deviation from the true course heading when setting your compass reading. Add any westerly.

"East is least, West is best"

mike hallam.