VTM-91-772/C
-11-
5-2.2
Cosmetic Repairs
The antenna has been designed to meet and tested to pass Naval Shock and Vibration
requirements (MIL-S-901 and MIL-STD-167 respectively). Under and beyond normal expected
environmental stresses onboard ships, this antenna will not suffer mechanical or electrical
failure. However, over the life of the antenna a seam may become visible just above the top drip
shield. This may appear to be a “crack” in the antenna. However, this is only a surface crack
in the paint layers and the filler material. This location is where the aluminum radiator meets
the fibreglass base and since these materials have different coefficients of expansion, under high
mechanical stress(es), the paint may crack under the normal flexural movement of the materials.
An example can be seen in the below photograph.
IT IS IMPORTANT TO NOTE IN NO WAY WHATSOEVER IS THIS CRACK
RELATED TO A MECHANICAL FAILURE OF THE ANTENNA.
Should this occur, repairing is not considered to be necessary. Otherwise, to restore the
antenna’s cosmetic appearance, it can be refinished as follows:
- use a small scraper to remove all the loose paint flakes;
- lightly sand the area down;
- re-coat with a durable ship-board grade paint;
- if excessive filler material has fallen out, the groove can be filled back in with a quality
acrylic or silicone sealant after painting.
