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putt for dough
21st Oct 2009, 14:25
Hello all

I need help from those of you in the know. So if you could help
with an informative and factual reply, I could possibly buy you a beer at
flyerz!

Now I am busy with ATP instruments and cant seem to remember
how to work out residual deviation on a non cardinal hdg
eg: 135 deg. Now I can do it on 90,180,270,360 deg,
but not on the headings in between.
Can somebody please help me with the tricks!

Thanks in advance :ok:

south coast
21st Oct 2009, 15:39
Yeah, R150 to Nency.

Der absolute Hammer
21st Oct 2009, 19:33
For aircraft and the ATPL, I think you only have to worry about Coefficients A. B and C.

Coefficient B = Dev E - Dev W/2
Coefficient C = Dev N - Dev S/2

Coefficient A = Dev N + Dev S + Dev E + Dev W/4

That is right I think?

Then is it not true that Coefficient A is the residual deviation and that that is what you apply to the non cardinal or quadrantal headings?

putt for dough
22nd Oct 2009, 06:42
Hammer... thanks mate but I seem to remember it being a little more
complicated than that. I just cant remember what? :{

rudder hard over
22nd Oct 2009, 06:58
There is one method where the SIN curve is plotted on the headings given. When drawn the the answer is obtained from the graph. Not sure if thats the question you are refering to though.

Der absolute Hammer
22nd Oct 2009, 07:05
The Australians, having a magnetic personality have some of the answers here....
http://www.casa.gov.au/wcmswr/_assets/main/airworth/awb/34/008.pdf

Otherwise, perhaps a call to Babcock, Aeronav or wherever you did your course or acquired your notes?
If anything polarises in the brain, I will post once more.

putt for dough
22nd Oct 2009, 07:49
@rudder hard over.
I seem to remember something like that. was it plotting against only the sine curve or also the cosine curve? this really is baffling. thanks man.
trouble is I finished my comm too long ago. :O

@hammer
shot man, will look at that site.

Propellerpilot
25th Oct 2009, 05:42
Coefficiant B is the Sine curve and Coefficiant C is the Cosine curve as they are in 90° to each other. It's all in the notes...

putt for dough
26th Oct 2009, 07:16
Thanks propeller pilot. I am well aware of that.
My question was on an intermediate heading and not
a cardinal heading.
But thanks for stating the obvious. :hmm:

Got it sorted now, thanks to those who replied.

Der absolute Hammer
26th Oct 2009, 13:51
Come on then, cough up the dough, how does it become calculated please?

putt for dough
27th Oct 2009, 11:27
Its a silly thing called interpolation Hammer.
Who would of thought?
Anyway after many hours and phone calls I found interpolation
worked.
Just glad that horrible subject is now over.

1 to go :}