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I appeal here for information.

The US Navy published a restricted text in 1949, titled "Naval Arctic 
Operations Handbook".  This book basically is advice to Naval Officers who 
will engage in artic ops.

In Volume II, on page 402, there is a small section of advice on celestial navigation.  I quote:

"CELESTIAL
Celestial navigation is the most important method of fixing position in polar 
regions.  The procedure is similar to procedures used elsewhere but 
refractions and coriolis corrections must be applied.  Computed altitudes and 
azimuth can be determined by use of tables in H.O. 249, H.O. 214, - volumes 
VIII and X, and H.O.230.  The tables in H.O.249 are the easiest to use, but 
this volume includes only certain stars and a similar volume is needed for 
the sun, moon and planets.  Another valuable aid is the Weems Star Alititude 
Curves, but again these are restricted to the selection of particular stars.  
By the use of these tables it is advisable to plan which stars are to be used 
and prepare in advance the altitudes and azimuths.  In addition meridional 
altitude shots should be precomputed to save time and effort in flight.

The astrocompass is used for check gyro precession and heading.  This 
instrument should be properly aligned before take-off.

The Mark V sextant will give excellent results, providing it is handled with 
care.  The flashlight batteries should be kept warm by carrying them inside 
the flying suit because low temperatures affect their generating power.  
Breathing directly on the index prism of the sextant will cause ice or frost 
to form and should be avoided.  In the event ice does form, the surface 
should be warmed with the hand until the ice melts and then the prism should 
be cleaned carefully with a soft clean cloth or lens tissue."

End quote.

There is an obvious typographical error in this, it should read H.O.214, - 
volumes VIII and IX.  I don't believe volume X exists.

I have searched for a reference to Hydrographic Office Publication Number 230 
but can find nothing.  Does anyone on the list have any information on this 
publication?  It must be a tabular solution to the navigational triangle for 
high latitudes, but thats as much as I have.

Perhaps Mr. Eno would weigh in on the particulars of handling a sextant in the 
Arctic and the advice offered by the US Navy.

Best Regards
Brad 




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