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sin A=(cos Lat sin LHA)/cos h
(sin was missing in front of A:-)

Alex.

On Mon, 9 Apr 2012, Gary LaPook wrote:

>
> Well, I checked the formula that you posted and it doesn't work. This is what you posted:
>
> All Russian books use even simpler formula:
> sin
> A=(cos Lat sin LHA)/cos h.
> where A is the asimuth, h is the altitude.
>
> Try it again, maybe there is a typo.
>
> gl
>
> --- On Sun, 4/8/12, Alexandre E Eremenko  wrote:
>
> From: Alexandre E Eremenko 
> Subject: [NavList] Re: Why are NA sight reduction tables not
> To: NavList@fer3.com
> Date: Sunday, April 8, 2012, 4:26 PM
>
>
> Absolutely sure. Checked.
> Just check it, comparing with other formulas,
> using your calcultor, if you have any doubts:-)
>
> The asimuth it computes is between 0 and 90.
> Here is the rule to determine the quarter:
>
> The first letter (N or S) in the name of the asimuth quarter
> is the same as the letter in Lat, if Lat and Dec are
> of the same name.
> The first letter of the asymuth quarter is oposite to
> the letter in Lat, if Lat and Dec are of the oposite name.
>
> Sometimes it is not desirable to use h in the A calculation.
> For this case, there is another "Russian formula":
> cot A = (cos Lat tan Dec)/sin LHA - sin Lat cot LHA.
>
> Alex.
>
> On Sun, 8 Apr 2012, Gary LaPook wrote:
>
>>
>> Are you sure that is the correct formula for finding Azimuth?
>>
>> The standard formula is
>> sin A=(cos DEC sin LHA)/cos h.
>>
>> gl
>>
>> --- On Sun, 4/8/12, Alexandre E Eremenko  wrote:
>>
>> From: Alexandre E Eremenko 
>> Subject: [NavList] Re: Why are NA sight reduction tables not
>> To: NavList@fer3.com
>> Date: Sunday, April 8, 2012, 10:05 AM
>>
>>
>> Geoffrey,
>> Thanks.
>>
>> The formula for the asimuth in NA seems a little
>> more complicated than the one
>> taught by PE. I don't know what is the reason for this more complicated
>> formula.
>> All Russian books use even simpler formula:
>> sin A=(cos Lat sin LHA)/cos h.
>> where A is the asimuth, h is the altitude.
>> That's what I use.
>> It requires 3 inputs of angles to the calculator (without memory) while PS
>> requires 5
>> and NA requires 6.
>>
>> There are also modified Russian formulas optimized for the calculator with
>> one memory cell (like Casio f250), however I do not use them, because
>> they compute asimuth first and altitude second, while I need
>> only altitude in most cases for land observations.
>>
>> Alex.
>>
>> On Sun, 8 Apr 2012, Geoffrey Kolbe wrote:
>>
>>>
>>> At 16:08 08/04/2012, you wrote:
>>>
>>>> I would like to follow this discusion,
>>>> But what is the formula (for the calculator) taught by the Power Squadron?
>>>> Can anyone give me a link with this formula?
>>>
>>> 
http://www.akronpowersquadron.com/NauticalTools/SightReduction/SightReduction.shtml
>>>
>>>
>>>> (I know two formulas for sight reduction).
>>>
>>> Why Alex, there is a world of excitement waiting for you then. ;-)
>>>
>>> Geoffrey
>>>
>>>
>>>
>>>
>>>
>>> : http://fer3.com/arc/m2.aspx?i=118813
>>>
>>>
>>>
>>
>>
>>
>>
>>
>>
>>
>> : http://fer3.com/arc/m2.aspx?i=118818
>>
>>
>>
>
>
>
>
>
>
>
> : http://fer3.com/arc/m2.aspx?i=118845
>
>
>

   

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