Finding the degrees between two headings

nomad · #1 $Old$ 11-07-2008, 03:45 AM

Hi,

I have what I'm sure is a relatively simple problem, but the answer eludes me.

What is the equation to determine the number of degrees between two compass headings? For example:

If Heading 1 is 350 degrees & Heading 2 is 10 degrees then the delta is 20 degrees

or

If Heading 1 is 350 degrees & Heading 2 is 317 degrees then the delta is 33 degrees.

One other thing; the delta can obviously never be greater than 180 degrees.

All help appreciated.

Nomad.

skeeter · #2 $Old$ 11-07-2008, 08:15 PM

earboth · #3 $Old$ 11-08-2008, 12:15 AM

Quote:

Originally Posted by nomad $View Post$

Hi,

I have what I'm sure is a relatively simple problem, but the answer eludes me.

What is the equation to determine the number of degrees between two compass headings? For example:

If Heading 1 is 350 degrees & Heading 2 is 10 degrees then the delta is 20 degrees

...

That depends on how you define the "measuring direction" with angles.

Normally an angle is measured counterclockwise and then the difference between an heading of 350° and a heading of 10° is 340°.

nomad · #4 $Old$ 11-19-2008, 01:11 PM

Thanks, but this is a specific case where the measurement can be in either direction (whichever is the lesser), hence the difference in angle never being allowed to be greater than 180 degrees.

nomad.

skeeter · #5 $Old$ 11-19-2008, 04:04 PM

Quote:

Originally Posted by nomad $View Post$

Thanks, but this is a specific case where the measurement can be in either direction (whichever is the lesser), hence the difference in angle never being allowed to be greater than 180 degrees.

nomad.

that's why you only need to look at (or visualize) the directions on the compass rose ... pilots don't use a formula.