ENR 1.13 UNLAWFUL INTERFERENCE
1. GENERAL
1.1 An act of unlawful interference includes any act or attempted act such as to jeopardize the safety of civil aviation and air transport, including:
a) Unlawful seizure of aircraft in flight or on the ground;
b) Hostage-taking on board aircraft or at aerodromes;
c) Forcible intrusion on board an aircraft, at an airport, or on the premises of an aeronautical facility;
d) Introduction on board an aircraft or at an airport of a weapon or hazardous device intended for criminal purposes.
1.2 The following procedures are intended for use by aircraft when an act of unlawful interference occurs, and the aircraft is unable to notify an ATS unit of this fact.
2. PROCEDURES FOR FLIGHT CREW
2.1 Unless considerations aboard the aircraft dictate otherwise, the pilot-in-command should attempt to continue flying on the assigned track and at the assigned cruising level at least until able to notify an ATS unit or until within ATS surveillance coverage.
2.2 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 121.500 MHz and other appropriate frequencies, unless considerations aboard the aircraft dictate otherwise. Other equipment, such as onboard transponders and data links, should also be used when advantageous and circumstances permit;
b) Set the SSR transponder to Mode A/3A Code 7500 to silently signal unlawful interference, provided it will not jeopardize the safety of the flight;
c) Proceed in accordance with applicable special procedures for in-flight contingencies, as promulgated in ICAO Doc 7030 (Regional Supplementary Procedures - MID Region); or
d) If no applicable regional procedures have been established, proceed at a cruising level which differs from the levels normally used for IFR flight in the area by 150 M (500 FT) if operating within RVSM airspace or below FL410, or by 300 M (1 000 FT) if above FL410.
3. ATS ACTION IN THE EVENT OF UNLAWFUL INTERFERENCE
3.1 Upon receiving notification or recognizing indications of an act of unlawful interference (e.g., SSR Code 7500, sudden unauthorized track deviation, or distress broadcasts), ATS units in Damascus FIR shall:
a) Immediately confirm the status of the flight without exacerbating the situation;
b) Notify appropriate civil aviation and national military control authorities;
c) Provide increased separation between the affected aircraft and all other known traffic;
d) Clear frequencies of non-essential traffic to reduce distraction; and
e) Render all possible assistance to the flight without interrupting the flight crew's decision-making process.