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giladal
11th Oct 2009, 05:05
Hi.
I am studying for the ATPL written and I came to a little issue with the calculations of CH Lat and D Lat.

I know you have to mulitply it by 60, but how do you go and multiply a coordinate such as 24°23'. 24 x 60 is 1440 I am not understanding how to get the answer for the 23'.

Any ideas?

Not looking for the answer, just the method.

Thanks

Exaviator
11th Oct 2009, 06:56
Not quite sure just what you are trying to achieve. If you give an example of the question it would help to provide an answer. Cheers:confused:

giladal
11th Oct 2009, 07:12
Sorry.

Point A is 23°33'S and point B is 47°56'S. If an aircraft is traveling from from A to B, what is the Ch Lat and what is the D Lat?

Ch Lat comes out to be 24°23'S. I got that.

I can't seem to figure out how to calculate D Lat. The answer is 1463'S. but I dont know how they came up with that number.

Keith.Williams.
11th Oct 2009, 07:30
For any change of position you must subtract the old position from the new one.

In this case you must subtract 23°33'S from 47°56

Doing the degrees first we have 47 - 23 = 24 degrees
Doing the minutes we have 56 - 33 = 23 minutes

So the change is 24 degres and 23 minutes

But DLong is stated in minutes so we multiply 24 degrees by 60 to get 1440 minutes

Now add the 23 minutes to get the total DLong of 1463 minutes.

It is of course all much easier if you have a calculator that can work in minutes and degrees and learn how to use it. If you are planning to sit the JAR ATPL exams you should do this.

giladal
11th Oct 2009, 07:33
Thank you sir.

I dont know why I didnt think of just adding the minutes... :)

Now it makes sense..


Thanks again

Abagnale
11th Oct 2009, 15:01
Jesus...I knew americans were not the most clever people,but that's not even a primary school level...Just shocking...:hmm:

lpokijuhyt
11th Oct 2009, 15:35
Just out of curiosity, where are you taking the exams? with which CAA? I noticed your location is listed as Los Angeles?

giladal
11th Oct 2009, 18:07
Abagnale (http://www.pprune.org/members/298005-abagnale): Thank you for the compliments.

I live in Los Angeles, but plan to convert my licenses to Israeli licenses. This is not even close to what you have to learn for the FAA ATP.