NOTE: The items specified will provide ground
points with a resistance of no more than 10,000 ohms
to ground if the resistance of the surrounding soil
or rock is less than 2,000,000 ohm-centimeters. In
high resistivity soils, over 2,000,000
ohm-centimeters, 3 meter (10 foot) or sectional rods
may be used to obtain the required resistivity to
ground; however, where rock is encountered,
additional rods, a counterpoise, or ground grid may
be necessary. Resistance to ground for static
electricity dissipation may be as much as 1,000,000
ohms. Static grounds are not designed for aircraft
lightning protection or for equipment grounding.
Grounding devices installed in hangar floors are
intended to serve for airplane static and equipment
grounding. The resistance to ground for each device
will be no more than 25 ohms. This requirement
should not be a problem since the rods will be
bonded to the facility ground. The resistance to
ground of grounding rods installed in all other
areas should be no more than 10,000 ohms.
Coordination with grounding requirements listed in
other sections should be done to avoid duplication.
It is recommended that this specification, and other
contract requirements for mooring and grounding
points, be coordinated with ER 1110-3-430, Design of
US Army Airfield Aircraft Mooring and Grounding
Points for Rotary Wing Aircraft.
The mooring points in this specification are
applicable to Army rotary wing aircraft only. The
grounding points are applicable to both Army and Air
Force aircraft.