The Seaplane Pilots Association

AIM 5-6-2: Interception Procedures

General
1. Identification intercepts during peacetime operations are vastly different from those conducted under increased states of readiness. Unless otherwise directed by the control agency, intercepted aircraft will be identified by type only. When specific information is required (i.e. markings, serial numbers, etc.) the interceptor aircraft will respond only if the request can be conducted in a safe manner. During hours of darkness or Instrument Meteorological Conditions (IMC), identification of unknown aircraft will be by type only. The interception pattern described below is the typical peacetime method used by air interceptor aircrews. In all situations, the interceptor aircraft will use caution to avoid startling the intercepted aircraft and/or passengers.
Intercept phases (see Figure 5-6-1)
1. Phase One - Approach Phase:
  During peacetime, intercepted aircraft will be approached from the stern. Generally two interceptor aircraft will be employed to accomplish the identification. The flight leader and wingman will coordinate their individual positions in conjunction with the ground controlling agency. Their relationship will resemble a line abreast formation. At night or in IMC, a comfortable radar trail tactic will be used. Safe vertical separation between interceptor aircraft and unknown aircraft will be maintained at all times.
2. Phase Two - Identification Phase
  The intercepted aircraft should expect to visually acquire the lead interceptor and possibly the wingman during this phase in visual meteorological conditions (VMC). The wingman will assume a surveillance position while the flight leader approaches the unknown aircraft. Intercepted aircraft personnel may observe the use of different drag devices to allow for speed and position stabilization during this phase. The flight leader will then initiate a gentle closure toward the intercepted aircraft, stopping at a distance no closer than absolutely necessary to obtain the information needed. The interceptor aircraft will use every possible precaution to avoid startling intercepted aircrew or passengers. Additionally, the interceptor aircrews will constantly keep in mind that maneuvers considered normal to a fighter aircraft may be considered hazardous to passengers and crews of nonfighter aircraft. When interceptor aircrews know or believe that an unsafe condition exists, the identification phase will be terminated. As previously stated, during darkness or IMC identification of unknown aircraft will be by type only. Positive vertical separation will be maintained by interceptor aircraft throughout this phase.
3. Phase Three - Post Intercept Phase
  Upon identification phase completion, the flight leader will turn away from the intercepted aircraft. The wingman will remain well clear and accomplish a rejoin with the leader.
Communication interface between interceptor aircrews and the ground controlling agency is essential to ensure successful intercept completion. Flight Safety is paramount. An aircraft which is intercepted by another aircraft shall immediately:
1. Follow the instructions given by the intercepting
2. Notify, if possible, the appropriate air traffic services unit.
3. Attempt to establish radio communication with the intercepting aircraft with the appropriate intercept control unit, by making a general call on the emergency frequency 243.0 MHz and repeating this call on the emergency frequency 121.5 MHz, if practicable, giving the identity and position of the aircraft and the nature of the flight.
4. If equipped with SSR transponder, select MODE 3/A Code 7700, unless otherwise instructed by the appropriate air traffic services unit. If any instructions received by radio from any sources conflict with those given by the intercepting aircraft by visual or radio signals, the intercepted aircraft shall request immediate clarification while continuing to comply with the instructions given by the intercepting aircraft.<

Table 5-6-1 INTERCEPTION SIGNALS
Signals initiated by intercepting aircraft and responses by intercepted aircraft (as set forth in ICAO Annex 2--Appendix A, 2.1)

INTERCEPTING Aircraft Signals	Meaning	INTERCEPTED Aircraft Responds	Meaning

DAY--Rocking wings from a position slightly above and ahead of, and normally to the left of, the intercepted aircraft and, after acknowledgment, a slow level turn, normally to the left, on to the desired heading. NIGHT--Same and, in addition, flashing navigational lights at irregular intervals. Note 1: Meteorological conditions may require the intercepting aircraft to take up a position slightly above and ahead of, and to the right of, the intercepted aircraft and to make the subsequent turn to the right. 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 racetrack patterns and to rock its wings each time it passes the intercepted aircraft.	You have been intercepted. Follow me.	DAY--Rocking wings and following. NIGHT--Same and, in addition, flashing navigational lights at irregular intervals.	I understand and will comply.

DAY or NIGHT--An abrupt breakaway maneuver 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.	Rocking wings.	I understand and will comply.

DAY--Circling airport, lowering landing gear and overflying runway in direction of landing. NIGHT--Same and, in addition, showing steady landing lights.	Land at this airport.	DAY--Lowering landing gear, following the intercepting aircraft and, if after overflying the runway landing is considered safe, proceeding to land. NIGHT--Same and, in addition, showing steady landing lights (if carried).	I understand and will comply.

DAY or NIGHT--If it is desired that the intercepted aircraft follow the intercepting aircraft to an alternate airport, the intercepting aircraft raises its landing gear and uses the "You have been intercepted" signals.	Understood, follow me.	DAY--Raising landing gear while passing over landing runway at an altitude exceeding 1,000' but not exceeding 2,000' AGL, and continuing to circle the airport. NIGHT--Flashing landing lights while passing over landing runway at altitudes described for DAY. If unable to flash landing lights, flash any other lights available.	Airport you have designated is inadequate.
If it is decided to release the intercepted aircraft, the intercepting aircraft uses the "You may proceed" signals prescribed for intercepting aircraft.	Understood, you may proceed.		Airport you have designated is inadequate.

Performs the "You may proceed" maneuver listed above.	Understood.	The pilot switches on and off all available lights at irregular intervals.	Cannot comply or in distress.



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