HGA-7001
Installation Manual
Document: 862-A0089_IM issue 1.6
COMPANY CONFIDENTIAL
Page 28 of 45
5.3.2
Mounting/Adaptor Plate
(1)
Some fabricated construction or mounting/adaptor plate will be required in all cases to adapt
the airframe to the flat antenna base. If the construction results in water traps, suitable
drainage and anti-corrosion measures must be taken in these areas.
(2)
Various types of installation kits are available to suit most aircraft types. Please consult the
Supplier for more information.
5.4
Painting
NOTE: THE METALLIC SEGMENTS ON THE LIGHTNING DIVERTER STRIPS MUST NEVER BE
PAINTED.
(1)
If minor paint touch-ups or repainting of the radome is required, refer to Cobham document
OP-121 REPAINTING HGA-7001 ANTENNA.
5.5
Sealing
(1)
The HGA-7001 is a breathing design and therefore no special precautions need to be taken for
sealing of the antenna itself.
(2)
The installer must take suitable precautions to prevent water from becoming trapped between
the HGA-7001 and the aircraft fuselage, as this may result in corrosion.
NOTE: IT IS NOT RECOMMENDED TO APPLY SEALER OR FILLER UNDER THE ANTENNA.
5.6
Grounding
(1)
The base of the antenna is painted except at the grounding areas.
(2)
One of the following methods of grounding the antenna must be used:
NOTE: THE GROUNDING PATH IN THE METHODS THAT FOLLOW IS COMPLETED BY BOLTS INTO
THE FUSELAGE AND / OR EARTHING STRAPS.
(a)
Grounding via antenna mounting bolts through an adaptor plate into the fuselage.
The mounting holes can be used as a ground only if the anchor nuts are properly
grounded.
(b)
Grounding of the antenna via the bonding points to an adaptor or mounting plate.
1)
8 Bonding points at the base of the mounting holes on the underside of the
antenna provide an annular area with an outer diameter of Ø16.4 mm (Ø0.63”) for
direct bonding of the antenna to the mounting hardware. The corresponding area
on the adapter or mounting hardware is bared of paint and suitably protected
against corrosion, providing the ground path when the antenna is attached.
2)
Verify that the O-rings around the 8 (mounting holes) bonding areas of the
antenna are in place before securing the antenna. Refer to Figure 11.
(c)
Grounding via the ground stud. Refer to Figure 11 for the location of the ground stud.
1)
The thread is #10-32 UNC and the length 12 mm (0.5”).
2)
Use a torque wrench to tighten the nut to 1.5 Nm (1.1 ft-lb).
Summary of Contents for 677-A0173
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