The following procedures and visual signals apply over the territory and territorial waters of the Kingdom of Thailand in the event of interceptions of an aircraft.
follow the instructions given by the intercepting aircraft, interpreting and responding to visual signals in accordance with the specifications on page ENR 1.12-3;
notify, if possible, the appropriate Air Traffic Services unit;
attempt to establish radio communication with the intercepting aircraft or with the appropriate intercept control unit, by making a general call on the emergency frequency 121.5 MHz, giving the identity of the intercepted aircraft and the nature of the flight, and if no contact has been established and if practicable, by repeating this call on the emergency frequency 243 MHz; and
if equipped with SSR transponder, select Mode A, Code 7700, unless otherwise instructed by the appropriate Air Traffic Services unit.
| PHRASE | PRONUNCIATION | MEANING |
|---|---|---|
| CALL SIGN (call sign) | KOL SA-IN (call sign) | My call sign is (call sign) |
| WILCO | VILL-KO | Understood, will comply |
| CAN NOT | KANN NOTT | Unable to comply |
| REPEAT | REE-PEET | Repeat your instruction |
| AM LOST | AM LOSST | Position unknown |
| MAYDAY | MAYDAY | I am in distress |
| HIJACK | HI-JACK | I have been hijacked |
| LAND (place name) | LAAND (place name) | I request to land at (place name) |
| DESCEND | DEE-SEND | I require descent |
| PHRASE | PRONUNCIATION | MEANING |
|---|---|---|
| CALL SIGN | KOL SA-IN | What is your call sign? |
| FOLLOW | FOL-LO | Follow me |
| DESCEND | DEE-SEND | Descend for landing |
| YOU LAND | YOU LAAND | Land at this aerodrome |
| PROCEED | PRO-SEED | You may proceed |
Note: The word "interception" in this context does not include intercept and escort service provided, on request, to an aircraft in distress, in accordance with the Search and Rescue Manual (Doc 7333).
Syllables to be emphasized are underlined.
The call sign required to be given is that used in radiotelephony communications with Air Traffic Services units and corresponding to the aircraft identification in the flight plan.
Circumstances may not always permit, nor make desirable, the use of the phrase “HIJACK”.
SIGNALS INITIATED BY INTERCEPTING AIRCRAFT AND RESPONSES BY INTERCEPTED AIRCRAFT
| Series | INTERCEPTING Aircraft Signals | Meaning | INTERCEPTED Aircraft Responds | Meaning |
|---|---|---|---|---|
| 1 |
DAY or NIGHT - Rocking aircraft and flashing navigational lights at irregular intervals (and land ing lights in the case of a helicopter) from a posi tion slightly above and ahead of and normally to the left of, the intercepted aircraft (or to the right if the intercepted aircraft is a helicopter) and, after acknowledgement, a slow level turn, nor mally to the left, (or to the right in the case of a helicopter) on the desired heading Note 1: Meteorological conditions or terrain may required the intercepting aircraft to reverse the positions and direction of turn given above in Series 1. Note 2: If the intercepted aircraft is not able to keep pace with the intercepting aircraft, the latter is expected to fly a series of race - track patterns and to rock the aircraft each time it passes the intercepted aircraft. | You have been inter cepted. Fol low me. |
DAY or NIGHT - Rocking aircraft, flashing navigation lights at irregular intervals and fol lowing. Note: Additional action required to be taken by intercepted aircraft is prescribed in Chapter 3, 3.8, | Understood will comply. |
| 2 |
DAY or NIGHT - An abrupt break-away manoeuvre from the intercepted aircraft consist ing of a climbing turn of 90° or more without crossing the line of flight of the intercepted air craft. | You may proceed. | DAY or NIGHT - Rocking the aircraft | Understood will comply. |
| 3 |
DAY or NIGHT - Lowering landing gear (if fitted), showing steady landing lights and over-flying runway in use or, if the intercepted aircraft is a helicopter, overflying the helicopter landing area. In the case of helicopters, the intercepting heli copter makes a landing approach, coming to hover near to the landing area. | Land at this aerodrome. | DAY or NIGHT - Lowering landing gear, (if fit ted), showing steady landing lights and fol lowing the intercepting aircraft and, if, after over-flying the runway in use or helicopter landing area, landing is considered safe, pro ceeding to land. | Understood will comply. |
SIGNALS INITIATED BY INTERCEPTED AIRCRAFT AND RESPONSES BY INTERCEPTING AIRCRAFT
| Series | INTERCEPTING Aircraft Signals | Meaning | INTERCEPTED Aircraft Responds | Meaning |
|---|---|---|---|---|
| 4 |
DAY or NIGHT - Raising landing gear (if fitted) and flashing landing lights while passing over runway in use or helicopter landing area at a height exceeding 300 m (1 000 ft) but not exceeding 600 m (2 000 ft) [in the case of a heli copter, at a height exceeding 50 m (170 ft) but not exceeding 100 m (330 ft) above the aero drome level, and continuing to circle run-way in use or helicopter landing area. If unable to flash landing lights, flash any other lights available. | Aerodrome you have designated is inadequate. |
DAY or NIGHT - If it is desired that the intercepted aircraft follow the intercepting air-raft to an alternate aerodrome, the inter cepting aircraft raises its landing gear (if fitted) and uses the Series 1 signals prescribed for intercepting aircraft. If it is decided to release the intercepted air-raft, the intercepting aircraft uses the Series 2 signals prescribed for intercepting aircraft. | Understood, follow me. |
| 5 |
DAY or NIGHT - Regular switching on and off of all available lights but in such a manner as to be distinct from flashing lights. | Cannot com ply. | DAY or NIGHT - Use Series 2 signals pres cribed for intercepting aircraft | Understood. |
| 6 |
DAY or NIGHT - Irregular flashing of all available lights. | In distress | DAY or NIGHT - Use Series 2 signals pre scribed for intercepting aircraft. | Understood. |