NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Ho 208
From: John Rae
Date: 2005 Nov 3, 14:37 -0800
From: John Rae
Date: 2005 Nov 3, 14:37 -0800
I also have a copy of HO 208 and HO211 ( as well as
some HO214 etc.)
HO208 requires that an assumed position be selected
so that the assumed latitude is an integral whole degree, and that the local
hour angle is also an integral whole degree. (Similar requirements to make
at least one of these angles an integral whole degree is common to probably all
of the commonly used inspection tables, HO214 for example)
HO211 permits the use of a DR (dead reckoning)
position.
Both of these methods (HO208 and HO211) are
relatively easy to use, and HO208 is a smaller book.
If a navigator is taking sufficient shots of
several bodies over a relatively short time to obtain a fix, then either method
will be effective.
But if the navigator is using only the sun, taking
a mid-morning sight, and a mid-afternoon sight, and advancing the line of
position from the morning observation, then complications set in if the
calculations are from an assumed position that is not the DR position. Not
to say that it cannot be accurately done, but that there are more chances for
error.
Therefore I prefer HO211, or the use of a
electronic calculator using the DR positions.
