ELT ELT406GPS, Installation, Operating And Maintenance Manual

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5.3.2 New Installations
If this is a new installation or if the current installation is unacceptable, the following guidelines
can help to find a suitable location:
•
RTCA suggests the aft section of the fuselage. This gives the greatest rate of survivability
as it is least likely to receive damage during a crash.
•
Care should be taken in choosing a location that allows ease of maintenance.
•
Accessibility in case of a crash.
•
Locate the unit to minimize cable runs to the antenna (under six feet is optimum).
•
Avoid locations that are subjected to chemical fluids such as de-icing compounds,
cleaning fluids, and hydraulics. Although the unit has been designed to withstand most
of these compounds, any long term exposure to these chemicals will damage aircraft
wiring.
Mount the ELT so that the longitudinal axis of the ELT (the axis extending through the longest
dimension) is aligned with that of the aircraft within 10º. The ELT mount can be rotated about
the longitudinal axis, i.e. the ELT can be mounted on the floor, walls or overhead, so long as it
‘points’ to the front of the aircraft.
A template has been provided to lay the basic hole pattern for installation. Make sure the pattern
is laid out to ensure the forward mark is pointing toward the nose of the aircraft. Mark and drill
four mounting holes using a #20 drill bit. Install the mounting tray. Use the 8-32 X 5/8” screws
and fasteners provided.
5.3.3 Helicopter Installations
As with any installation it is important to adhere to all helicopter manufacturers’ instructions and
the latest FAA rules and regulations. For a non-US registered aircraft consult your local aviation
authority for any specific requirements.
Traditional helicopter ELT installations required the unit be mounted at a 45
0
downward sloping
angle to be most likely activated in the event of a crash. The existing 45
0
mount should not be
re-used. Changes to TSO C91a and TSO C126 increased the sensitivity of the G-switch over the
older TSO C91 requirements. The 45
0
mounting angle tends to preload the G-switch, and results
in false activations from abrupt landings, severe maneuvers, etc.
The Emerging Lifesaving Technology 406 ELT PN 51220-H42 with internal GPS is equipped
with multi axis G-switches. This allows the installation be made at any angle, but the standard
has /- 10
0
of centerline. Always face the unit towards the nose of the aircraft.