PDA

View Full Version : ATPL General Nav question


steggers
1st Oct 2007, 11:38
Hi guys, wonder if you could help me? I don't understand how they've come up with the answer: -

With regards to finding the "Change of Latitude" if the two latitudes are in the same hemisphere the angles are subtracted. That i understand but the question is: -

"Find the change of latitude between 87 degress 13'S and 26 degress 37'S?"

The answer they've given is "60 Degrss 36' but how have they reached it???????

Sharky12t
1st Oct 2007, 11:50
Hi there,

Not sure I understand the problem here,

87 13'-
26 37'

=60 36'

First subtract the 26 degrees from 87 13' gives 61 13'

Then subtract 37' from 61 13' gives 60 36'

Remember there's only 60' in 1 deg.

If I've missed the point of your question feel free to clarify.

Sharky

steggers
1st Oct 2007, 12:17
ok, right i understand the 1st bullet point but then I dont understand

"Then subtract 37' from 61 13' gives 60 36'"

Is it something to do with 60' in 1 degree????

Halfwayback
1st Oct 2007, 13:01
There are only 60 minutes of arc (') in one degree!

Similarly there are only 60 seconds (") of arc in one minute of arc!

You are trying to find the difference so, as you correctly say, if they are in the same hemisphere subtract the lesser from the greater and if they are in different hemispheres add the two together!

HWB

steggers
1st Oct 2007, 13:23
Thanks guys i understand it now!!!!!

wbryce
1st Oct 2007, 16:49
Best advise for G.Nav is ''draw a flipping diagram"! Good luck with G.Nav, I found it a really enjoyable subject! Bit complicated at times but highly satisfying when you it all comes together.