TO THE CONVENTION ON INTERNATIONAL CIVIL
AVIATION
NINTH EDITION –JULY 1990
This edition incorporates all amendments
adopted by the
Council prior to 13 March 1990 and supersedes,
on 14 November 1991,
all previous editions of Annex 2.
For information regarding the application of
the Standards,
see Foreword.
INTERNATIONAL CIVIL AVIATION ORGANIZATION
ATTACHMENT A. INTERCEPTION OF CIVIL AIRCRAFT
(Note. - See Chapter 3, 3.8 of the Annex and
associated Note)
Note. - In the
interest of completeness, the substance of the provisions in Appendix 2 to the
Annex is incorporated in this Attachment.
1. In accordance with
Article 3 d) of the Convention on International Civil Aviation the Contracting
States of ICAO “undertake, when issuing regulations or their state aircraft,
that they will have due regard for the safety of navigation of civil aircraft”.
As interceptions of civil aircraft are, in all cases, potentially hazardous,
the Council of ICAO has formulated the following special recommendations which
Contracting States are urged to implement through appropriate regulatory and
administrative action. The uniform application by all concerned is considered
essential in the interest of safety of civil aircraft and their occupants. For
this reason the Council of ICAO invites Contracting States to notify ICAO of
any differences which may exist between their national regulations or practices
and the special recommendations hereunder.
2. General
2.1 Interception of civil aircraft should be
avoided and should be undertaken only as a last resort. If undertaken, the
interception should be limited to determining the identity of the aircraft,
unless it is necessary to return the aircraft to its planned track, direct it
beyond the boundaries of national airspace, guide it away from a prohibited,
restricted or danger area or instruct it to effect a landing at a designated
aerodrome. Practice interception of civil aircraft is not to be undertaken.
2.2 To eliminate or reduce the need for
interception of civil aircraft, it is important that:
a) all possible efforts be made by intercept
control units to secure identification of any aircraft which may be a civil
aircraft, and to issue any necessary instructions or advice to such aircraft,
through the appropriate air traffic services units. To this end, it is
essential that means of rapid and reliable communications between intercept
control units and air traffic services units be established and that agreements
be formulated concerning exchanges or information between such units on the
movements of civil aircraft, in accordance with the provisions of Annex 11;
b) areas prohibited to all civil flights and
areas in which civil flight is not permitted without special authorization by
the State be clearly promulgated in aeronautical information publications (AIP)
in accordance with the provisions of Annex 15, together with the risk, if any,
of interception in the event of penetration of such areas. When delineating
such areas in close proximity to promulgated ATS routes, or other frequently
used tracks, States should into account the availability and over-all systems
accuracy of the navigation systems to be used by civil aircraft and the ability
to remain clear of the delineated areas;
c) the establishment of additional navigation
aids be considered where necessary to ensure the civil aircraft are able safely
to circumnavigate prohibited or, as required, restricted areas.
2.3 To eliminate or reduce the hazards inherent
in interceptions undertaken as a last resort, all possible efforts should be
made to ensure coordinated actions by the pilots and ground units concerned. To
this end, it is essential that Contracting States take steps to ensure that:
a) all pilots of civil aircraft be made fully
aware of the actions to be taken by them and the visual signals to be used, as
specified in Chapter 3 and Appendix 1 of this Annex;
b) operators or pilots-in-command of civil
aircraft implement the provisions in Annex 6, Parts I, II and III regarding the
capability of aircraft to communicate on 121.5 MHz and the availability of
interception procedures and visual signals on board aircraft;
c) all air traffic services personnel be made
fully aware of the actions to be taken by them in accordance with the
provisions of Annex 11, Chapter 2 and the PANS-RAC (Doc 4444);
d) all pilots-in-command of intercepting aircraft
be made aware of the general performance limitations of civil aircraft and of the
possibility that intercepted civil aircraft may be in a state of emergency due
to technical difficulties or unlawful interference;
e) clear and unambiguous instructions be issued
to intercept control units and to pilots-in-command of potential intercepting
aircraft, covering interception maneuvers, guidance of intercepted aircraft,
action by intercepted aircraft;
air-to-air visual signals, radio-communication with intercepted aircraft, and
the need to refrain from resorting to the use of weapons;
Note. - See
paragraphs 3 to 8.
f)
intercept
control units and intercepting aircraft be provided with radiotelephony
equipment compatible with the technical specifications of Annex 10, Volume 1 so
as to enable them to communicate with intercepted aircraft on the emergency
frequency 121.5 MHz;
g) secondary surveillance radar facilities be
made available to the extent possible to permit intercept control units to
identify civil aircraft in areas where they might otherwise be intercepted.
Such facilities should permit recognition of discrete four-digit codes in Mode
A, including immediate recognition of Mode A, Codes 7500, 7600 and 7700.
3.
Interception maneuvers
3.1 A standard method
should be established for the maneuvering of aircraft intercepting a civil
aircraft in order to avoid any hazard for the intercepted aircraft. Such method
should take due account of the performance limitations of civil aircraft, the
need to avoid flying in such proximity to the intercepted aircraft that a
collision hazard may be created and the need to avoid crossing the aircraft's
flight path, or to perform any other maneuver in such a manner that the wake
turbulence may be hazardous, particularly if the intercepted aircraft is a
light aircraft.
3.2
Maneuvers for visual identification
The following method
is recommended for the maneuvering of intercepting aircraft for the purpose of
visually identifying a civil aircraft:
The intercepting
aircraft should approach the intercepted aircraft from astern. The element
leader, or the single intercepting aircraft, should normally take up a position
on the left (port) side, slightly above and ahead of the intercepted aircraft,
within the field of view of the pilot of the intercepted aircraft, and
initially not closer to the aircraft than 300 m. Any other participating
aircraft should stay well clear of the intercepted aircraft, preferably above
and behind. After speed and position have been established, the aircraft
should, if necessary, proceed with Phase II of the procedure.
The element leader,
or the single intercepting aircraft, should begin closing in gently on the
intercepted aircraft, at the same level,
until no closer than absolutely necessary to obtain the information needed. The
element leader, or the single intercepting aircraft, should use caution to
avoid startling the flight crew or the passengers or the intercepted aircraft,
keeping constantly in mind the fact that maneuvers considered normal to an
intercepting aircraft may be considered hazardous to passengers and crews of
civil aircraft. Any other participating aircraft should continue to stay well
clear of the intercepted aircraft. Upon completion of identification, the
intercepting aircraft should withdraw from the vicinity of the intercepted
aircraft as outlined in Phase III.
The element leader,
or the single intercepting aircraft, should break gently away from the
intercepted aircraft in a shallow dive. Any other participating aircraft should
stay well clear or the intercepted aircraft and rejoin their leader.
3.3
Maneuvers for navigational guidance
3.3.1 If, following the identification maneuvers
in Phase I and Phase II above, it is considered necessary to intervene in the
navigation of the intercepted aircraft, the element leader, or the single
intercepting aircrafts should normally take up a position on the left (port)
side, slightly above and ahead of the intercepted aircraft, to enable the
pilot-in-command of the latter aircraft to see the visual signals given.
3.3.2 It is indispensable that the
pilot-in-command of the intercepting aircraft be satisfied that the
pilot-in-command of the intercepted aircraft is aware of the interception and
acknowledges the signals given. If repeated attempts to attract the attention
of the pilot-in-command of the intercepted aircraft by use of the Series 1
signal in Appendix 1, Section 2 are unsuccessful, other methods of signaling
may be used for this purpose, including as a last resort the visual effect of
the reheat/afterburner, provided that no hazard is created for the intercepted
aircraft.
3.4 It is recognized that meteorological
conditions or terrain may occasionally make it necessary for the element
leader, or the single intercepting aircraft, to take up a position on the right
(starboard) side, slightly above and ahead of the intercepted aircraft, In such
case, the pilot-in-command of the intercepting aircraft must take particular
care that the intercepting aircraft is clearly visible at all times to the
pilot-in-command of the intercepted aircraft.
4.
Guidance of an intercepted aircraft
4.1 Navigational guidance and related
information should be given to an intercepted aircraft by radiotelephony,
whenever radio contact can be established.
Attachment A
4.2 When navigational guidance is given to an
intercepted aircraft, care must be taken that the aircraft is not led into
conditions where the visibility may be reduced below that required to maintain
flight in visual meteorological conditions and that the maneuvers demanded of
the intercepted aircraft do not add to already existing hazards in the event
that the operating efficiency of the aircraft is impaired.
4.3 In the exceptional case where an intercepted
civil aircraft is required to land in the territory overflown, care must also
be taken that:
a) the designated aerodrome is suitable for the
safe landing of the aircraft type concerned, especially if the aerodrome is not
normally used for civil air transport operations;
b) the surrounding terrain is suitable for
circling. Approach and missed approach maneuvers;
c) the intercepted aircraft has sufficient fuel
remaining to reach the aerodrome;
d) if the intercepted aircraft is a civil transport
aircraft, the designated aerodrome has a runway with a length equivalent to at
least 2 500 mat mean sea level and a bearing strength sufficient to support the
aircraft; and
e) whenever possible, the designated aerodrome is
one that , is described in detail in the relevant aeronautical information
publication.
4.4 When requiring a civil aircraft to land at
an unfamiliar aerodrome, it is essential that sufficient time be allowed it to
prepare for a landing, bearing in mind that only the pilot-in-command of the
civil aircraft can judge the safety of the landing operation in relation to
runway length and aircraft mass at the time.
4.5 It is particularly important that all
information necessary to facilitate a safe approach and landing be given to the
intercepted aircraft by radiotelephony.
5.
Action by intercepted aircraft
The Standards in
Appendix 2, Section 2 specify as follows:
“2.1 An aircraft
which is intercepted by another aircraft shall immediately:
a) follow the instructions given by the intercepting aircraft, interpreting and responding to visual signals in accordance with the specifications in Appendix 1;
b) notify, if possible, the
appropriate air traffic services unit;
c) 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 night; and if no
contact has been established and if practicable, repeating this call on the
emergency frequency 243 MHz;
d) if equipped with SSR transponder, select Mode A, Code 7700, unless otherwise instructed by the appropriate air traffic services unit.
"2.2 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.
"2.3 If any instruction received by radio from
any sources conflict 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.”
6. Air-to-air visual signals
The visual signals to
be used by intercepting and intercepted aircraft are those set forth in
Appendix I to this Annex. It is essential that intercepting and intercepted
aircraft adhere strictly to those signals and interpret correctly the signals
given by the other aircraft, and that the intercepting aircraft pay particular
attention to any signals given by the intercepted aircraft to indicate that it
is in stare of distress or urgency.
7. Radio-communication between intercept control unit or the intercepting aircraft and the intercepted aircraft
7.1 When an interception is being made, the
intercept control unit and the intercepting aircraft should:
a) first attempt to establish two-way communications with the intercepted aircraft in a common language on the emergency frequency 121.5 MHz, using the call signs “INTERCEPT CONTROL”, “INTERCEPTOR (call sign)” and “INTERCEPTED AIRCRAFT” respectively; and
b) failing this, attempt to establish two-way communication with the intercepted aircraft on such other frequency or frequencies as may have been prescribed by the appropriate ATS authority, or to establish contact through the appropriate ATS unit(s).
7.2 If radio contact is established during
interception but communication in a common language is not possible, attempts
must be made to convey instructions acknowledgement of instructions and
essential information by using the phrases and pronunciations in Table A-I and
transmitting each phrase twice.
8. Refraining from the use of weapons
Note. - In the
unanimous adoption by the 25th Session (Extraordinary) of the ICAO Assembly on
10 May 1984 of Article 3 bis to the Convention on International Civil Aviation,
the contracting States have recognized that "every State must refrain from
resorting to the use of weapons against civil aircraft in flight."
The use of tracer
bullets to attract attention is hazardous, and it is expected that measures
will be taken to avoid their use so that the lives of persons on board and the
safety of aircraft will not be endangered.
9. Co-ordination between intercept control
units and air traffic services units
It is essential that
close co-ordination be maintained between an intercept control unit and the
appropriate air traffic services unit during all phases of an interception of
an aircraft which is, or might be, a civil aircraft, in order that the air
traffic services unit is kept fully informed of the developments and of the
action required of the intercepted aircraft.
Table A-I
Phrases for use by
INTERCEPTING aircraft
Phrase Pronunciation1 Meaning
CALL SIGN KOL SA-IN What is your call sign?
FOLLOW FOL-LO Follow me
DECEND DEE-SEND Descend for landing
YOU LAND YOU LAAND Land at this aerodrome
PROCEED PRO-SEED You may proceed
Phrases for use by
INTERCEPTED aircraft
Phrase Pronunciation1 Meaning
CALL SIGN KOL SA-IN My call sign is (call sign)
(call sign)2 (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
HIJACK3 HI-JACK I have been hijacked
LAND LAAND I request to land at
(place name) (place name) (place name)
DESCEND DEE-SEND I require descent
1. In the second
column, syllables to be emphasized are underlined.
2. 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.
3. Circumstances
may not always permit, nor make desirable, the use of the phrase “HIJACK”.
(Note. -See Chapter 3, 3.8 of the Annex)
1. Principles to be
observed by States
1.1 To achieve the uniformity in regulations which
is necessary for the safety of navigation of civil aircraft due regard shall be
had by Contracting States to the following principles when developing
regulations and administrative directives:
a)
interception of
civil aircraft will be undertaken only as last resort;
b) if undertaken, an interception will be limited to determining the identity of the aircraft, unless it is necessary to return the aircraft to its planned track, direct it beyond the boundaries of national airspace, guide it away from a prohibited, restricted or danger area or instruct it to effect a landing at a designated aerodrome;
c)
practice
interception of civil aircraft will not be undertaken;
d)
navigational
guidance and related information will be given to an intercepted aircraft by
radiotelephony, whenever radio contact can be established; and
e)
in the case
where an intercepted civil aircraft is required to land in the territory
overflown, the aerodrome designated for the landing is to be suitable for the
safe landing of the aircraft type concerned.
Note. - In the
unanimous adoption by the 25th Session (Extraordinary) of the ICAO Assembly on
10 May 1984 of Article 3 bis to the Convention on International Civil Aviation,
the Contracting States have recognized that “every State must refrain from
resorting to the use of weapons against civil aircraft in flight.”
1.2 Contracting. States shall publish a standard
method that has been established for the maneuvering of aircraft intercepting a
civil aircraft. Such method shall be designed to avoid any hazard for the
intercepted aircraft.
Note. - Special
recommendations regarding a method for the maneuvering are contained in
Attachment A, Section 3.
1.3 Contracting States shall ensure that provision
is made for the use of secondary surveillance radar, where available, to
identify civil aircraft in areas where they may be subject to interception.
2. Action by intercepted aircraft
2.1 An aircraft which is intercepted by aircraft
shall immediately:
a) follow the instructions given by the
intercepting aircraft, interpreting and responding to visual signals in
accordance with the specifications in Appendix 1:
b) notify, if possible, the appropriate air
traffic services unit;
c) 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 natural of the flight; and if no contact has
been established and if practicable, repeating this call on the emergency
frequency 243 MHz;
d) if equipped with SSR transponder select Mode
A, Code 7700, unless otherwise instructed by the appropriate air traffic
services unit.
2.2 If any instructions received by radio from
any sources conflict with those given 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
2.3 If any instructions received by radio from
and sources conflict 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
3. Radio-communication during interception
If radio contact is
established during interception but communication in a common language in not
possible, attempts shall be made to convey instructions, acknowledgement of
instructions and essential information by using the phrases and pronunciation
in Table 2.1 and transmitting each phrase twice: