8/15/19 AIM  TBL 5 − 6 − 2 Intercepting Signals INTERCEPTING SIGNALS Signals and Responses During Aircraft Intercept Signals initiated by intercepted aircraft and responses by intercepting aircraft (as set forth in ICAO Annex 2-Appendix 1, 2.2) Series INTERCEPTED Aircraft Signals Meaning INTERCEPTING 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 300m (1,000 ft) but not exceeding 600m (2,000 ft) (in the case of a helicopter, at a height exceeding 50m (170 ft) but not exceeding 100m (330 ft) above the aerodrome level, and continuing to circle runway 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 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. 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 comply. DAY or NIGHT-Use Series 2 signals prescribed for intercepting aircraft. Understood. 6 DAY or NIGHT − Irregular flashing of all available lights. In distress. DAY or NIGHT-Use Series 2 signals prescribed for intercepting aircraft. Understood. National Security and Interception Procedures 5 − 6 − 12