Emergency Locator Transmitter (Elt); Removal And Installation Of The Elt - Piper Navajo Chieftain PA-31-350 Service Manual

NAVAJO CHIEFTAIN SERVICE MANUAL
SECTION XII
ELECTRONICS
12-1. INTRODUCTION. This section provides the information necessary to perform an operation check
of the Piper Automatic Locator Transmitter and/or the Piper Automatic Locator Transmitter with a Pilot's
Remote Switch. Included are the appropriate removal and installation instructions to facilitate battery
replacement.
12-2. EMERGENCY LOCATOR TRANSMITTER.
12-3. DESCRIPTION. The electrical power for the ELT transmitter is supplied by its own self-contained
battery. With the C.C.C. ELT only, aircraft power is required to shut off the transmitter with the remote
switch. Per FAA regulations, magnesium batteries must be replaced 2 years and lithium batteries 5 years
from date of manufacture stamped on the battery pack. If the transmitter has been used in an emergency
situation during this 2 or 5 year period or has more than one hour of accumulated test time, the battery
must be replaced according to FAA regulations. To replace the battery pack in the transmitter, it is
necessary, to remove the ELT from the airplane. (Refer to Paragraph 12-4, 12-6 or 12-7, depending on the
brand name of the ELT being used.)
12-4. REMOVAL AND INSTALLATION (GARRETT MFG. LTD. 2 year, magnesium battery. Refer to
Figure 12-1.) The ELT is located underneath the dorsal fin between sta. 304.75 and sta. 317.00.
a. Remove the access panel on the dorsal fin.
b. Set the ON/ARM/OFF switch on the transmitter to the OFF position.
c. Disconnect the antenna coax from the transmitter.
d. Disconnect the harness to the pilot's remote switch from the transmitter. (Serial Nos.
31-7405153 and up.)
e. Remove the rear mounting bracket by pulling the plastic knob out. Remove the transmitter from
the airplane.
f. Remove the two long or four short screws securing the transmitter plain end cap. Remove the
plain end cap.
g. Disconnect the battery connector from the board terminals.
h. Withdraw the battery pack from the transmitter case.
i. Before installing the new battery pack, check the replacement date by adding two years to the
date of manufacture on the battery. Transfer this date onto the ELT label.
j. Slide the new battery pack, plain end first, into transmitter. It may be necessary to rotate the
battery slightly to get it seated properly in the transmitter case and to achieve correct orientation of the
battery connector.
k. Connect the battery connector to board terminals.
1. Insure O-ring is fitted in plain end cap and correctly seated.
m. Refit end cap and secure with the screws previously removed.
NOTE
Do not overtighten the two long screws.
Reissued: 9/23/80 ELECTRONICS
4 A10