Safety issue

Safety issue description

The Australian Airline Pilot Academy flying school flight crew operation manual only required pilots to select ALT on the transponder, as part of the Pre Line Up Scan Action Flow and associated Checklist prior to entering the runway. The use of a transponder during taxi would normally provide an additional source of positional data to other pilots, aiding visual identification and alerted 'see‑and‑avoid' to other aircraft.
Issue number AO-2024-041-SI-01
Issue owner Australian Airline Pilot Academy
Transport function Aviation: General aviation
Issue status Closed – Adequately addressed
Date issue released 13/11/2025
Issue status justification

The proactive safety action taken by AAPA to engage the transporter after engine start addresses the identified safety issue.

Safety action

Action type Proactive action
Action number AO-2024-041-PSA-04
Organisation Australian Airline Pilot Academy
Action description

AAPA has advised the ATSB that changes have been made to its PA-28 Flight Crew Operating Manual, and Quick Reference Handbook, which reflects the transponder being selected to ALT mode after start in both the checklist as well as being incorporated as part of the Scan Action Flow (SAF).

In addition to this, AAPA has then implemented a series of checks to validate that the ALT mode has been selected after start, where it is rechecked in the: 

  1. pre-take off SAF
  2. pre-take off checklist (& expanded checklist)
  3. pre-line up SAF
  4. pre-line up checklist (& expanded checklist).

This notification was made to CASA and changes made to AAPA manual suite with an effective date of 30 April 2025.
Action status Closed

Safety action

Action type Safety advisory notice
Action number AO-2024-041-SAN-01
Organisation Pilots and operators of mode S transponder equipped aircraft
Action description

The effective use of the mode S transponder from first movement of the aircraft can serve as an effective tool in adding another layer of collision avoidance between aircraft on the ground. Utilising the mode S transponder with ADS-B OUT enabled is the most effective way of making an aircraft electronically conspicuous and delivering maximum interoperability with other aircraft as well as the ground ATM environment. The ATSB advises pilots and operators to review their procedures to ensure that mode S transponders are on from first movement of the aircraft, particularly at non-controlled aerodromes.