AIM - SAR 3.8 - ELT Testing Procedures

Any testing of an ELT must be conducted only during the first 5 minutes of any
UTC hour and restricted in duration to not more than 5 seconds.

When originally installed in an aircraft, and when parts of the ELT system are moved
or changed, an ELT will be tested in accordance with CAR 571. Every few months, or
as recommended by the manufacturer, pilots should test their ELT. Such tests can be
done between two stations separated by at least half a kilometer, or by a single aircraft,
using its own radio receiver.

(a) Two station ELT test

(i) Position the aircraft about one-half kilometer from the tower, FSS or
other aircraft which will listen on 121.5 MHz. Ensure the listening
station is clearly visible from the aircraft, as ELT transmissions are
line-of-sight. Intervening obstacles such as hills, buildings or other
aircraft may prevent the listening station from detecting the ELT
transmission.

(ii) Using the aircraft radio or other pre-arranged signals, establish contact
with the listening station. When the listening station confirms that it is
ready, switch the ELT function to “ON”. After no more than 5 seconds,
turn the ELT function switch to “OFF”. The listening station should
confirm that the ELT was heard.

(iii) Reset the ELT function switch to “ARM”.

(iv) Tune the aircraft radios to 121.5 MHz to confirm that the ELT stopped
transmitting.

(v) If the listening station did not hear the ELT, investigate further before
flying the aircraft.

Often it will be impractical to co-ordinate an ELT test with a tower, FSS or other
aircraft. In such circumstances, pilots can use the following procedures to test their
ELTs. Such tests are to be conducted in the first 5 minutes of any UTC hour, and test
transmissions must be limited to 5 seconds or less.

When conducting the two-station test at a busy airport, take due regard of tower or FSS
workload. Keep the voice radio transmissions to a minimum. If the “listening” station
does not hear the ELT transmission, it may be necessary to move the aircraft to another
location on the airfield to conduct the test.

(b) Single station ELT test

(i) Tune aircraft radio receiver to 121.5 MHz.

(ii) Switch on the ELT just long enough to hear the tone, and immediately
return the function switch to “ARM”; it is best to have another person in
the cockpit to ensure the minimum “on air” test period. Do not exceed
the 5 seconds “on-air” time.

(iii) Recheck 121.5 MHz on the aircraft receiver to ensure that the ELT
stopped transmitting.

When conducting a single aircraft test, it is possible that the aircraft radios will hear the
ELT output, even though the ELT power transistor is defective, and will not be
detected by a receiver half a kilometer away. However, this test will uncover a totally
unserviceable ELT, and is better than no test.

CARs 605.40