MIL-PRF-10436N
3.4.8.1 Magnetic standard. The compass shall operate in a magnetic field with a horizontal
component equal to the local standard ± .01 oersted and vertical component of the local standard
±.03 oersted (Continental United States). The local standard shall be established using the
U.S. Geological Survey (Department of the Interior) Epoch 1995 Map No. GP1002-D, Magnetic
Declination of the U.S.; Epoch 1995 Map No. G1002-F, Magnetic Total Intensity of the U.S.;
Epoch 1995 Map No. GP986-V, Magnetic Vertical Intensity of the U.S.; and Epoch 1995
Map No. GP986-H, Magnetic Horizontal Intensity of the U.S.
3.4.9 Mechanical performance. The compass shall meet the subordinate requirements with
the compass in the operational configuration and away from all magnetic effects external to the
compass caused by buildings, vehicles, electrical devices, etc.
3.4.9.1 Damping. The magnetic assembly, shall come to rest within 6 seconds of time after
being deflected 540 ±20 mils from a position of equilibrium (see 4.4.1.9.1).
3.4.9.2 Freedom of rotation when tilted. The operation of the compass shall not be adversely
affected when it is tilted 8.0 ± 0.1 degree from the horizontal and rotated 360 degrees in a plane
normal to the longitudinal axis of the pivot (see 4.4.1.9.2).
3.4.9.3 Compass error. The error in magnetic azimuth, including that caused by pivot friction,
shall not be greater than 40 mils (see 4.4.1.8).
3.4.9.4 Friction error. The error caused by friction between the pivot supporting the dial and
its bearing shall not be greater than 20 mils (see 4.4.1.9.3).
3.4.10 Illumination. The compass shall have internal, self-exciting light sources of constant
luminosity for sighting and reading. In addition, the dial assembly shall have a light source on
the permanent magnet to indicate north and the bezel crystal shall have a light source to aid in
setting readings and sighting. The "E" (east) and "W" (west) markings shall also be illuminated.
All sources shall be mounted flush with or recessed in their mounting surfaces and encapsulated
to inhibit damage (see 4.4.1.9.4).
3.4.10.1 Luminosity. Luminous material, in the final form, shall have a peak spectral output
of 530 ±30 nanometers. The brightness of the luminous sources installed in the completed
compass shall be sufficient to allow the performance of compass functions in any ambient light
and under any of the environmental conditions specified herein (see 4.4.1.9.4.1). Self-exciting
luminous sources shall have a minimum service life of 12 years (see 6.2).
3.5 Environmental requirements.
3.5.1 Water leakage. The complete compass shall be capable of being submerged into water
without leakage into the interior of the compass, where it will adversely affect performance
directly or indirectly (see 4.4.2.1).
3.5.2 Shock. The compass shall not be damaged or suffer performance degradation when
dropped from a height of 90 cm (see 4.4.2.2).
3.5.3 Low and high temperatures. When exposed to temperature extremes of -44°C and 68°C,
the compass shall function properly and shall not be damaged (see 4.4.2.3).
4
For Parts Inquires call Parts Hangar, Inc (727) 493-0744
© Copyright 2015 Integrated Publishing, Inc.
A Service Disabled Veteran Owned Small Business