ENR 1.12  INTERCEPTION OF CIVIL AIRCRAFT

1  INTERCEPTION PROCEDURES

The following procedures and visual signals apply over the territory and territorial waters of the Republic of Lithuania in the event of interception (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)) of an aircraft.

1.1 An aircraft which is intercepted by another aircraft shall immediately:
  1. follow the instructions given by the intercepting aircraft, interpreting and responding to visual signals in accordance with the specifications;
  2. notify, if possible, the appropriate ATS unit;
  3. attempt to establish radio communication with the intercepting aircraft or with the appropriate intercept control unit, by making a general call on the emergency FREQ 121.500 MHZ, giving the identity of the intercepted aircraft and the nature of the flight, and if no contact has been established and if practicable, repeating this call on the emergency FREQ 243.000 MHZ;
  4. if equipment with SSR transponder, select Mode A, Code 7700, unless otherwise instructed by the appropriate air ATS unit.
1.2 If radio contact is established during interception but communication in plain language is not possible, attempts shall be made to convey instructions, acknowledgment of instructions and essential information by using the phrases and pronunciations in the following table and transmitting each phrase twice:
PhasePronunciation1)Meaning
CALL SIGN (call sign2))KOL-SA-IN (call sign)My call sign is (call sign)
WILCOVILL-KOUnderstood. Will comply
CAN NOTKANN NOTTUnable to comply
REPEATREE-PEET (RY-PYT)Repeat your instruction
AM LOSTAM LOSSTPosition unknown
MAYDAYMAYDAY (MEI DEI)I am in distress
HIJACK3)HI-JACK (HAI-DZEK)I have been hijacked
LAND (place name)LAAND (place name)I request to land at (place name)
DESCENDDEE SEND (DY SEND)I require descend
  1. Syllables to be emphasized are printed in bold letters.
  2. The call sign required to be given is that used in radiotelephony communications with ATS units and corresponding to the aircraft identification in the FPL.
  3. Circumstances may not always permit, nor make desirable, the use of the phrase "HIJACK".

The following phrases shall be used by the intercepting aircraft and transmitted twice in the circumstances described in the preceding paragraph:

PhasePronunciation1)Meaning
CALL SIGNKOL-SA-IN What is your call sign?
FOLLOW FOL-LO (FOLOU)Follow me
DESCENDDEE SEND (DY SEND)Descend for landing
YOU LANDYOU LAAND (JU LAAND)Land at this aerodrome
PROCEEDPRO-SEED (PRO-SYD)You may proceed
  1. Syllables to be emphasized are printed in bold letters.
1.3 If any instructions received by radio from any sources conflict with those given by the intercepting aircraft by visual signals, the intercepted aircraft shall request immediate clarification while continuing to comply with the visual instructions given by the intercepting aircraft.
1.4 If instructions received by radio from any sources with those given by the intercepting aircraft by radio, the intercepted aircraft shall request immediate clarification while continuing to comply with the radio instructions given by the intercepting aircraft.
1.5 The visual signals are detailed in the table “SIGNALS FOR USE IN THE EVENT OF INTERCEPTION”.

2  SIGNALS FOR USE IN THE EVENT OF INTERCEPTION

2.1  Signals initiated by intercepting aircraft and responses by intercepted aircraft
SeriesINTERCEPTING Aircraft SignalsMeaningINTERCEPTED Aircraft RespondsMeaning
1DAY or NIGHT - Rocking aircraft and flashing navigational lights at irregular intervals (and landing lights in the case of a helicopter) from a position 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 acknowledgment, a slow level turn, normally to the left, (or to the right in the case of a helicopter) on the desired heading.
Note 1: Meteorological conditions or terrain may require 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 intercepted. Follow me.DAY or NIGHT - Rocking aircraft, flashing navigational lights at irregular intervals and following.Understood, will comply.
2DAY or NIGHT - An abrupt break-away manoeuvre from the intercepted aircraft consisting of a climbing turn of 90 degrees or more without crossing the line of flight of the intercepted aircraft.You may proceed.DAY or NIGHT - Rocking the aircraft.Understood, will comply.
3DAY or NIGHT - lowering landing gear (if fitted), showing steady landing lights and overflying runway in use or, if the intercepted aircraft is a helicopter, overflying the helicopter landing area. In the case of helicopters, the intercepting helicopter makes a landing approach, coming to hover near to the landing area.Land at this aerodrome.DAY or NIGHT - Lowering landing gear, (if fitted), showing steady landing lights and following the intercepting aircraft and, if, after overlying the runway in use or helicopter landing area, landing is considered safe, proceeding to land.Understood, will comply.
2.2  Signals initiated by intercepted aircraft and responses by intercepting aircraft
SeriesINTERCEPTED Aircraft RespondsMeaningINTERCEPTING Aircraft SignalsMeaning
4DAY 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 1000 FT (300 M) but not exceeding 2000 FT (600 M) (in the case of a helicopter, at a height exceeding 170 FT (50 M) but not exceeding 330 FT (100 M) above the aerodrome level, and continuing to circle the runway in use or helicopter landing areas. 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 aircraft to an alternate aerodrome, the intercepting 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 aircraft, the intercepting aircraft uses the Series 2 signals prescribed for intercepting aircraft.		Understood, follow me.
Understood, you may proceed.
5DAY or NIGHT – Regular switching on and off of all available lights but in such a manner as to be distinct from flashing lights.Cannot complyDAY or NIGHT - Use Series 2 signals prescribed for intercepting aircraft.Understood.
6DAY or NIGHT – Irregular flashing of all available lights.In distress.DAY or NIGHT – Use Series 2 signals prescribed for intercepting aircraft.Understood.