Question for the classically trained Astro navigators; when Dec approaches Lat

[capnsensible]

Sorry ... yes - with all the other - forgot that one !!

Peace brother!

 

[Refueler]

Refueler, I agree with what you say about taking noon sights with the sun overhead (even if your choice of words is sometimes a bit abrasive).

I don't agree that a fix is possible with only 2 north/south lops (ie longitudes) no matter what your course and speed is. Sorry Skylark, this last bit is not really relevant to your original question.

I become more abrasive when my Professional ability becomes questioned. I am sure that DTI examining board would have something to say about it !

To clear up the N/S LOP ... agreed of course its not possible to derive position from crossing two N/S LOP's ... BUT my point was that a N / S PL (lets call it Position Line ... PL) ... run along the course line is valid as its 90 deg to the E/W latitude produced by MP. The noon fix will then be valid - not as 'capnsensible' erroneously claims impossible.

Reason I said 'capnsensibles' claim a Running fix is not possible is crap - because the noon fix by PL / MP is whatever always a running fix ... and a N/S run up to an E/W should in theory give better result.

As to multiple sun sights as is the ships case - its often 2/O and 3/O take sun sights at least twice each in the morning for run up to noon ... if they are N/ S PL's - the taking of multiples will be a check on their accuracy if nothing else ... (we'll ignore that Dec and Lat change over time).

 

[Skylark]

................I don't agree that a fix is possible with only 2 north/south lops (ie longitudes) no matter what your course and speed is. Sorry Skylark, this last bit is not really relevant to your original question.

I originally asked two questions. The second one was about MP, the first was about an acceptable intercept / angle of cut between forenoon and afternoon PLs. Related to any rule of thumb difference between Dec and Lat. It was only a few hours ago but after reading the tension from within the responses, it feels like a lifetime

After I put my nice clean and oiled bicycle away. this is how I prefer to relax during house arrest, rather than get drawn into heated discussions :-

Many thanks for taking the time to respond. Happy Easter to all

 

[capnsensible]

Didnt last long.

Email this guy and tell them they've been doing it wrong for at least 40 years. Im sure he will listen.

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