NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
From: Greg Rudzinski
Date: 2012 Apr 29, 21:31 -0700
60 Sun sights were taken this last weekend to settle the question of wether presetting the micrometer drum on a Navy MK 5 octant will improve individual sight accuracy.
30 preset obs. vs. 30 normal set obs. :
Preset micrometer- Intercept average 0.2' T with spread (scatter) of 2.1' moa.
Normal set micrometer- Intercept average 0.1' A with spread of 2.7' moa.
52 of 60 observations had intercepts less than 1.0' moa. A pair of outliers were removed from the data set with intercepts over 3.0 moa ( double the next largest intercept ).
Conclusions:
A small improvement (+/- 0.3' moa) for single observations can be realized by presetting the Navy MK 5 micrometer drum to the even minute then waiting for horizon tangency.
Greg Rudzinski
[NavList] Navy MK 5 Octant Using Natural Horizon
From: Greg Rudzinski
Date: 26 Apr 2012 16:24
For those who have the Navy MK 5 aircraft bubble octant and would like to improve conventional non-bubble observations using the horizon in prism (natural horizon) try presetting the micrometer drum to an even minute then let the body rise or set to horizon tangency. The Navy MK 5 micrometer drum is only graduated every two minutes of arc so it is very easy to get awkward in between readings.
Greg Rudzinski
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