2. Drill 0.562” (14.3 mm) hole in aircraft skin.
2.4.1.4 Installation
1) Metal adapter plates should be used if the curvature or compound radius of the aircraft skin is such that antennas cannot be directly installed vertically with their plates mounted flat to the aircraft outer surface.
2) Backing plates or doublers should be installed to ensure adequate support for associated air loading during flight. Refer to AC 43.13 for complete information.
3) Remove the .-28 hex nut and external tooth lock washer from the base of the antenna.
4) Insert antenna connector through mounting hole, make sure the “O” ring remains in the base of the antenna connector flange groove and that the connector has sufficient clearance through the aircraft skin.
5) Place the lock washer and the hex nut on the inside of the aircraft and sandwich the aircraft skin between the base of the antenna and lock washer followed by the hex nut. Tighten the hex nut to between 25 to 30 inch lbs (280 to 340 Newton-cm).
6) Apply a small, smooth fillet with RTV sealant around the periphery of the antenna base to seal out moisture.
7) For maximum signal strength, the length of the antenna coax to the ELT should be as short as possible (use of the standard 6-foot (1.8 M) coax is recommended when possible).
2.4.1.5 Composite Aircraft Installation
Except for preparation instructions and installation of a ground plane, installation is the same. Refer to AC 43.13 for complete information.
2.4.2 Rod Antenna – Artex P/N 110-338
See Figure 21. Refer to FAA Advisory Circular 43.13 for guidance. It is the responsibility of the installation agency to determine the appropriate and adequate antenna installation.
To ensure adequate support for associated air loading during flight, use of a backing plate or doubler (not supplied) may be required.
2.4.2.1 Type of Aircraft
The Rod Antenna is designed for installation on fixed or rotor wing subsonic aircraft and is rated for a maximum airspeed of 350 KTAS (Knots True Airspeed at 25,000 feet).
2.4.2.2 Location
The Rod Antenna (P/N 110-338) must be mounted on the top of the aircraft to assure maximum ‘visibility’ of satellites (406 MHz). The best location is the upper aft portion of the fuselage. It should be mounted vertically and away from projections such as a propeller, tail surfaces, or the shadow of larger antennas.
2.4.2.3 Preparation
8) Prepare the surface for antenna installations in such a manner to ensure a ground contact of less than 0.003.. If bare metal surfaces are needed for surface preparation they should be treated with Alodine.1200 (or similar application) to eliminate aluminum oxidation.
9) Use the Outline Drawing (P/N 110-338, Figure 21) to determine hole pattern and drill size.
2.4.2.4 Installation
1) Metal adapter plates should be used if the curvature or compound radius of the aircraft skin is such that antennas cannot be directly installed vertically with their plates mounted flat to the aircraft outer surface. 中国航空网 www.aero.cn 航空翻译 www.aviation.cn 本文链接地址：DESCRIPTION, OPERATION, INSTALLATION AND MAINTENANCE MANUAL ME406P ELT(15)
