16 June 1999
refers to the Grid Layout Sheet, enclosure (3), which depicts the grid and
allows for entry of the dimensions being used, each station's magnetic
declination, the minimum and the maximum declination of the compass rose and
the mean magnetic declination.
2. The step-by-step procedures for conducting the magnetic survey or certifi-
cation are contained in enclosure (4). These instructions are directly
correlated to the MC-2 Magnetic Certification Sheet, enclosure (5), and the
Station Magnetic Data Work Sheet, enclosure (7). Enclosure (6) contains the
detailed instructions for performing the calculations required on the Station
Magnetic Data Work Sheet.
3. Upon completion of the magnetic survey, azimuth observations must be made
to establish true azimuth control for the grid. If the grid can be easily
tied into an existing triangulation system, such as a prior compass rose
survey which contains the true azimuth of several prominent objects, then the
grid's true azimuth can be determined and the absolute value of declination
can be calculated. If this existing triangulation system is not available,
then a Polaris observation will be required. The instruction for obtaining
true azimuth by Polaris observations are contained in enclosure (8) and are
correlated to the Polaris Observation Data Sheet, enclosure (9).
4. After all of the calculations on the Station Magnetic Work Sheet have been
completed, the declination of each station must be entered on the Grid Layout
Sheet. The minimum and maximum declination must be determined to verify that
the range of declination of the compass rose meets the requirements of MIL-STD
765A, which limits the range to a maximum of twelve (12) minutes. The average
of all of the stations and hubs declination must be taken so that the mean
declination of the compass rose can also be entered.
5. If, after completion of the magnetic survey, it is determined that the
mean declination of the compass rose exceeds that by which the radial markings
are originally laid by more than 1/2 degree the radial lines must be re-laid.
Enclosure (10) provides procedures for re-laying radial lines.