Secondary surveillance radar
Secondary surveillance radar SSR and ADS-B
AIP GEN 3.4
| Circumstance | Phraseology |
|---|---|
| KEY
Pilot transmission |
|
1 To instruct setting of transponderNoteThe word ‘code’ is not used in transmissions. NoteADS-B and SSR are linked in many aircraft and terminating one will terminate the other. |
(a) Squawk (code) [and ident if required] |
| (b) [SQUAWK] (code) [AND IDENT if instructed by ATS] | |
| (c) Squawk normal | |
| To request: | |
| Reselection of the assigned mode and code | (d) Recycle [(mode)] (code) |
| Reselection of aircraft identification | (e) RECYCLING [(mode)] (code) |
| Confirmation of Mode A | (f) Re-enter Mode S (or ADS-B) aircraft identification |
| Code selection | (g) Confirm squawk (code) |
| Operation of the ident feature | (h) SQUAWKING (code) |
| Temporary suspension of transponder operation | (i) Squawk ident |
| (j) Transmit ADS-B ident | |
| (k) Squawk standby [transmit ADS-B only] | |
| Emergency code selection termination of SSR transponder or ADS-B transmitter operation | (l) Squawk mayday |
| Transmission of pressure altitude | (m) Stop squawk [transmit ADS-B only] |
| (n) Stop ADS-B transmission [squawk (code) only] | |
| Pressure setting check and confirmation of level | (o) Squawk charlie |
| Termination of pressure altitude transmission because of faulty operation | (p) Transmit ADS-B altitude |
| (q) Check altimeter setting and confirm level | |
| (r) Stop squawk charlie, wrong indication | |
| Altitude check confirmation of ADS-B operation | (s) Stop ADS-B altitude transmission [(wrong indication, or reason)] |
| Change to secondary transponder | (t) Verify [level] (level) |
| (u) ADS-B transmissions not received, confirm ADS-B operational | |
| (v) Select secondary transponder | |
| 2 Advice or traffic level Where the pressure altitude derived level information has not been verified |
(a) Unverified level (level) |