Unlawful interference general

The following procedures are intended as guidance for use by aircraft when unlawful interference occurs and the aircraft is unable to notify an ATS unit of this act.

When an occurrence of unlawful interference with an aircraft takes place or is suspected, ATS units shall attend promptly to requests by the aircraft. Information pertinent to the safe conduct of the flight shall continue to be transmitted and necessary action shall be taken to expedite the conduct of all phases of the flight, especially the safe landing of the aircraft.

Procedures

1) Unless considerations aboard the aircraft dictate otherwise, the pilot in command should attempt to continue flying on the assigned track and the assigned cruising level at least

until able to notify an ATS unit, or

until reaching an area with radar coverage.

2) When an aircraft subjected to an act of unlawful interference must depart from its assigned track or its assigned cruising level without being able to make radiotelephony contact with ATS, the pilot in command should whenever possible:

a) Attempt to broadcast warnings on the VHF emergency frequency and other appropriate frequencies unless considerations aboard the aircraft dictate otherwise. Other equipment such as on-board transponders, data links, etc, should also be used when it is advantageous to do so and circumstances permit, and

b) Proceed in accordance with the applicable special procedures for in-flight contingencies, where such procedures have been established and promulgated in Doc. 7030 - Regional Supplementary Procedures: or

c) If no applicable regional procedures have been established, proceed at the level which differs from the cruising levels normally used for IFR flight in the area by 300 m (1000 ft) if above FL 290 or by 150 m (500 ft) if below FL 290.

Air-groundcommunication failure (part 1)

Action by air traffic control units when unable to maintain two-way communication with an aircraft operating in a control area or control zone shall be as outlined in the following paragraphs:

As soon as it is known that two-way communication has failed, action shall be taken to ascertain whether the aircraft is able to receive transmissions from the air traffic control unit by requesting it to execute a special manoeuvre which can be observed by radar or transmit, if possible, a specified signal in order to indicate acknowledgement. (SSR Code 7600).

If the aircraft fails to indicate that it is able to receive and acknowledge transmissions, separation shall be maintained between aircraft having communication failure and other aircraft, based on the assumption that the aircraft will:

If in visual meteorological conditions (VMC):

a) continue to fly in VMC

b) land at the nearest suitable aerodrome,

c) report its arrival by the most expeditious means to the appropriate air traffic control unit.

If in Instrument meteorological conditions (IMC)

or when weather conditions are such that it does not appear feasible to complete the flight in accordance with VMC:

a) proceed according to the current flight plan to the appropriate designated navigation aid serving the aerodrome of destination and, when required to ensure compliance with b) hold over this aid until commencement of descent;

b) commence descent from the navigation aid specified in a) as close as possible to the expected approach time received and acknowledged; or, if no expected approach time has been received and acknowledged, at. or as close as possible to the estimated time of arrival resulting from the current flight plan;

c) complete a normal instrument approach procedure as specified for the designated navigation aid; and

d) land, if possible, within 30 minutes after the estimated time of arrival specified in b) or the last received and acknowledged expected approach time, whichever is later.