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Re: Very Small Altitude-Accurate Results
From: Ron Jones
Date: 2015 Aug 15, 21:27 -0700
From: Ron Jones
Date: 2015 Aug 15, 21:27 -0700
Since 2004 the Nautical Almanac has used the formula Ro' = 1.002'/tan(Ha +7.32/(Ha+4.32)) Eqn. 1
Prior to 2004 the Nautical Almanac used the formula Ro' = 1'/tan(Ha +7.31/(Ha+4.4)) Eqn. 2
The most significant difference in the two formulas occurs for values of Ha less than 2°
See attached PDF, the Ro values shown in the green column were calculated using Eqn. 1 and the Ro values in the grey column were calculated using Eqn. 2
File:
