Mode S Transponder Code

Rule 91.247(b) (PDF) requires that aircraft with Mode S transponder equipment installed must have a
unique Mode S address code assigned by the Director. AC91-2 gives details.

AC91-2 Assignment of mode S address (PDF)

To find out the code (binary) for an aircraft:

  1. Go to the Aircraft Register page.
  2. Enter the aircraft registration and click "Get Reg Mark".

On the right side you will see the code for that particular aircraft:

  • First line shows the binary country code for New Zealand.
  • Second line shows the unique binary aircraft code.
  • Third line shows the equivalent hexadecimal code.