What we do

You need a transponder with altitude reporting to fly in transponder airspace (CAR 605.35).

Every installed transponder, including its altitude reporting, must be tested every 24 months, to Standard 571, Appendix F (Standard 625, Appendix C, item 14).

The altitude your transponder reports must agree with your altimeter within 125 ft (Standard 571, Appendix F).

Both checks run on 24-month cycles, so we usually do them together in one visit.

Every modification is classed as major or minor using Transport Canada's criteria (Standard 571.06 and Standard 571, Appendix A). That decides the approved data and paperwork needed.

A major modification is reported to Transport Canada within 30 days of the aircraft returning to service (Standard 571.12 and Standard 571, Appendix L).

If the work changes your aircraft's empty weight or balance, the journey log entry is made before its next flight; after any change to the installed equipment, the weight and balance equipment list is updated (Standard 571, Appendix C).

121.5 MHz ELTs with standard batteries: maintenance at least every 12 months.

406 MHz ELTs (which also transmit on 121.5) with standard batteries: an operational test at least every 12 months, and a full performance test at least every 24 months.

ELTs with water-activated batteries: at least every five years.

Batteries are replaced on the manufacturer's schedule, and after any emergency use, an inadvertent activation of unknown duration, or once transmissions add up to more than one hour, with an operational test after each replacement.

We never transmit a live 406 MHz signal during testing, and operational tests are kept to the first five minutes of the hour (UTC), five seconds at most, so they can't be mistaken for a real emergency.