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Intercept Procedures

Introduction:

  • All aircraft entering the domestic U.S. Airspace from the outside is required to provide identification prior
    • The ADIZ is established for this reason
  • IFR or DVFR flight plan must be filed for: all operations in an ADIZ
NORAD Intercept Procedures
Figure 1: NORAD Intercept Procedures

Interception Procedures:

  • In conjunction with the FAA, Air Defense Sectors monitor air traffic and could order an intercept in the interest of national security or defense. Intercepts during peacetime operations are vastly different than those conducted under increased states of readiness. The interceptors may be fighters or rotary wing aircraft. The reasons for aircraft intercept include, but are not limited to:
    • Identify an aircraft;
    • Track an aircraft;
    • Inspect an aircraft;
    • Divert an aircraft;
    • Establish communications with an aircraft
  • When specific information is required (i.e., markings, serial numbers, etc.) the interceptor pilot(s) will respond only if, in their judgment, the request can be conducted in a safe manner. Intercept procedures are described in some detail in the paragraphs below. In all situations, the interceptor pilot will consider safety of flight for all concerned throughout the intercept procedure. The interceptor pilot(s) will use caution to avoid startling the intercepted crew or passengers and understand that maneuvers considered normal for interceptor aircraft may be considered hazardous to other aircraft
  • All aircraft operating in US national airspace are highly encouraged to maintain a listening watch on VHF/UHF guard frequencies (121.5 or 243.0 MHz). If subjected to a military intercept, it is incumbent on civilian aviators to understand their responsibilities and to comply with ICAO standard signals relayed from the intercepting aircraft. Specifically, aviators are expected to contact air traffic control without delay (if able) on the local operating frequency or on VHF/UHF guard. Noncompliance may result in the use of force

Intercept Phases:

  • Fighter Intercept Phases: (See FIG 5−6−1)

    • Approach Phase:

      • As standard procedure, intercepted aircraft are approached from behind
        • Typically, interceptor aircraft will be employed in pairs, however, it is not uncommon for a single aircraft to perform the intercept operation
      • Safe separation between interceptors and intercepted aircraft is the responsibility of the intercepting aircraft and will be maintained at all times
    • Identification Phase:

      • Interceptor aircraft will initiate a controlled closure toward the aircraft of interest, holding at a distance no closer than deemed necessary to establish positive identification and to gather the necessary information
      • The interceptor may also fly past the intercepted aircraft while gathering data at a distance considered safe based on aircraft performance characteristics
    • Post Interception Phase:

      • An interceptor may attempt to establish communications via standard ICAO signals
      • In time-critical situations where the interceptor is seeking an immediate response from the intercepted aircraft or if the intercepted aircraft remains non-compliant to instruction, the interceptor pilot may initiate a divert maneuver:
        • The interceptor flies across the intercepted aircraft's flight path (minimum 500 feet separation and commencing from slightly below the intercepted aircraft altitude) in the general direction the intercepted aircraft is expected to turn
        • The interceptor will rock its wings (daytime) or flash external lights/select afterburners (night) while crossing the intercepted aircraft's flight path
        • The interceptor will roll out in the direction the intercepted aircraft is expected to turn before returning to verify the aircraft of interest is complying
        • The intercepted aircraft is expected to execute an immediate turn to the direction of the intercepting aircraft
      • If the aircraft of interest does not comply, the interceptor may conduct a second climbing turn across the intercepted aircraft's flight path (minimum 500 feet separation and commencing from slightly below the intercepted aircraft altitude) while expending flares as a warning signal to the intercepted aircraft to comply immediately and to turn in the direction indicated and to leave the area
NOTE:
NORAD interceptors will take every precaution to preclude the possibility of the intercepted aircraft experiencing jet wash/wake turbulence; however, there is a potential that this condition could be encountered

Fighter Intercept Phases
Figure 2: Fighter Intercept Phases
  • Helicopter Intercept Phases: (See FIG 5−6−2)

    • Approach Phase:

      • Aircraft intercepted by helicopter may be approached from any direction, although the helicopter should close for identification and signaling from behind
      • Generally, the helicopter will approach off the left side of the intercepted aircraft
      • As with fighter intercepts, safe separation is always the responsibility of the intercepting aircraft
    • Identification Phase:

      • The helicopter will initiate a controlled closure toward the aircraft of interest, holding at a distance no closer than deemed necessary to establish positive identification and gather the necessary information
      • The intercepted pilot should expect the interceptor helicopter to take a position off his left wing slightly forward of abeam
    • Post Intercept Phase:

      • Visual signaling devices may be used in an attempt to communicate with the intercepted aircraft
        • Visual signaling devices may include, but are not limited to, LED scrolling signboards or blue flashing lights
      • If compliance is not attained through the use of radios or signaling devices, standard ICAO intercept signals may be employed
      • In order to maintain safe aircraft separation, it is incumbent upon the pilot of the intercepted aircraft not to fall into a trail position (directly behind the helicopter) if instructed to follow the helicopter so the helicopter pilot does not lose visual contact with the intercepted aircraft
NOTE:
Intercepted aircraft must not follow directly behind the helicopter thereby allowing the helicopter pilot to maintain visual contact with the intercepted aircraft and ensuring safe separation is maintained

Helicopter Intercept Phases
Figure 3: Helicopter Intercept Phases

Law Enforcement Operations:

  • Special law enforcement operations include in-flight identification, surveillance, interdiction, and pursuit activities performed in accordance with official civil and/or military mission responsibilities
  • To facilitate accomplishment of these special missions, exemptions from specified sections of the CFRs have been granted to designated departments and agencies. However, it is each organization’s responsibility to apprise ATC of their intent to operate under an authorized exemption before initiating actual operations
  • Additionally, some departments and agencies that perform special missions have been assigned coded identifiers to permit them to apprise ATC of ongoing mission activities and solicit special air traffic assistance
Intercept and Escort:
  • Based on SAR aircraft establishing visual and/or electronic contact with aircraft in difficulty
  • If a bailout or crash occurs SAR can be conducted without delay
  • Must be requested by a pilot in difficulty or a distress condition is declared

Intercept Signals
Signals initiated by intercepting aircraft and responses by intercepted aircraft (as set forth in ICAO Annex 2 - Appendix 1, 2.1)
Series Intercepting aircraft signals Meaning Intercepted Aircraft Responds Meaning
1 Day:
Rocking wings from a position slightly above and head 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:
Meteorological conditions or terrain 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:
If the intercepted aircraft is not able to keep pace with the intercepting aircraft, the latter is expected to fly a series of race-track patterns and to rock its wings each time it passes to the intercepted aircraft
You have been intercepted, follow me Aeroplanes:

Day:
Rocking wings and following

Night:
Same and, in addition, flashing navigation lights at irregular intervals

Helicopters:

Day or Night:
Rocking aircraft, flashing navigational lights at irregular intervals and following
Understood, will comply
2 Day or Night:
An abrupt break-away 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 Aeroplanes:

Day or Night:
Rocking wings

Helicopters:

Day or Night:Rocking aircraft
Understood, will comply
3 Day:
Circling aerodrome, lowering landing gear and overflying runway in direction of landing or, if the intercepted aircraft is a helicopter, overflying the helicopter landing area

Night:
Same and, in addition, showing steady landing lights
Land at this aerodrome Aeroplanes:

Day:
Lowering landing gear, following the intercepting aircraft and, if after overflying the runway landing is considered safe, proceed to land

Night:
Same and, in addition, showing steady landing lights (if carried)

Helicopters:

Day or Night:
Following the intercepting aircraft and proceeding to land, showing a steady landing light (if carried)
Understood, will comply
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 hight exceeding 300m (1000') but not exceeding 600m (2000') (in the case of a helicopter, at a height exceeding 50m (170') but not exceeding 100m (330') 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

Special Emergency (Air Piracy):

  • A special emergency is a condition of air piracy, or other hostile act by a person(s) aboard an aircraft, which threatens the safety of the aircraft or its passengers
  • The pilot of an aircraft reporting a special emergency condition should:
    • If circumstances permit, apply distress or urgency radio-telephony procedures including the details of the special emergency
    • If circumstances do not permit the use of prescribed distress or urgency procedures, transmit on the air/ground frequency in use at the time, as many as possible of the following elements spoken distinctly and in the following order:
      • Name of the station addressed (time and circumstances permitting)
      • The identification of the aircraft and present position
      • The nature of the special emergency condition and pilot intentions (circumstances permitting)
      • If unable to provide this information, use code words and/or transponder as follows:
        • Spoken Words: TRANSPONDER SEVEN FIVE ZERO ZERO" which means I am being hijacked/forced to a new destination
        • Transponder Setting: Mode 3/A, Code 7500
  • Code 7500 will never be assigned by ATC without prior notification from the pilot that the aircraft is being subjected to unlawful interference
      The pilot should refuse the assignment of Code 7500 in any other situation and inform the controller accordingly
    • Code 7500 will trigger the special emergency indicator in all radar ATC facilities
  • ATC will acknowledge and ask to confirm correct setting of 7500
  • If affirmative, or no reply is heard then ATC will not ask further questions but will flight follow, respond to pilot requests and notify appropriate authorities
  • If it is possible to do so without jeopardizing the safety of the flight, the pilot of a hijacked passenger aircraft, after departing from the cleared routing over which the aircraft was operating, will attempt to do one or more of the following things, insofar as circumstances may permit:
    • Maintain a true airspeed of no more than 400 knots, and preferably an altitude of between 10,000 and 25,000'
    • Fly a course toward the destination which the hijacker has announced
  • If these procedures result in either radio contact or air intercept, the pilot will attempt to comply with any instructions received which may direct the aircraft to an appropriate landing field or alter the aircraft's flight path off its current course, away from protected airspace

National Security:

  • National security in the control of air traffic is governed by 14 CFR Part 99
  • All aircraft entering domestic U.S. airspace from points outside must provide for identification prior to entry. To facilitate early aircraft identification of all aircraft in the vicinity of U.S. and international airspace boundaries, Air Defense Identification Zones (ADIZ) have been established
    • REFERENCE: AIM, Paragraph 5−6−5 , ADIZ Boundaries and Designated Mountainous Areas
  • Operational requirements for aircraft operations associated with an ADIZ are as follows:
    • Flight Plan. Except as specified in subparagraphs d and e below, an IFR or DVFR flight plan must be filed with an appropriate aeronautical facility as follows:
      • Generally, for all operations that enter an ADIZ
      • For operations that will enter or exit the U.S. and which will operate into, within or across the Contiguous U.S. ADIZ regardless of true airspeed
      • The flight plan must be filed before departure except for operations associated with the Alaskan ADIZ when the airport of departure has no facility for filing a flight plan, in which case the flight plan may be filed immediately after takeoff or when within range of the aeronautical facility
    • Two-way Radio. For the majority of operations associated with an ADIZ, an operating two-way radio is required. See 14 CFR Section 99.1 for exceptions
    • Transponder Requirements. Unless otherwise authorized by ATC, each aircraft conducting operations into, within, or across the Contiguous U.S. ADIZ must be equipped with an operable radar beacon transponder having altitude reporting capability (Mode C), and that transponder must be turned on and set to reply on the appropriate code or as assigned by ATC
    • Position Reporting
      • For IFR flight. Normal IFR position reporting
      • For DVFR flights:
        • The pilot reports to an appropriate aeronautical facility before penetration: the time, position, and altitude at which the aircraft passed the last reporting point before penetration and the estimated time of arrival over the next appropriate reporting point along the flight route;
        • If there is no appropriate reporting point along the flight route, the pilot reports at least 15 minutes before penetration: the estimated time, position, and altitude at which the pilot will penetrate; or
        • If the departure airport is within an ADIZ or so close to the ADIZ boundary that it prevents the pilot from complying with paragraphs (b)(1) or (2) of this section, the pilot must report immediately after departure: the time of departure, the altitude, and the estimated time of arrival over the first reporting point along the flight route
      • For inbound aircraft of foreign registry. The pilot must report to the aeronautical facility at least one hour prior to ADIZ penetration
    • Aircraft Position Tolerances
      • Over land, the tolerance is within plus or minus five minutes from the estimated time over a reporting point or point of penetration and within 10 NM from the centerline of an intended track over an estimated reporting point or penetration point
      • Over water, the tolerance is plus or minus five minutes from the estimated time over a reporting point or point of penetration and within 20 NM from the centerline of the intended track over an estimated reporting point or point of penetration (to include the Aleutian Islands)
    • Land−Based ADIZ. Land−Based ADIZ are activated and deactivated over U.S. metropolitan areas as needed, with dimensions, activation dates and other relevant information disseminated via NOTAM
      • In addition to requirements outlined in subparagraphs c1 through c3, pilots operating within a Land−Based ADIZ must report landing or leaving the Land−Based ADIZ if flying too low for radar coverage
      • Pilots unable to comply with all requirements must remain clear of Land−Based ADIZ. Pilots entering a Land−Based ADIZ without authorization or who fail to follow all requirements risk interception by military fighter aircraft
  • Except when applicable under 14 CFR Section 99.7, 14 CFR Part 99 does not apply to aircraft operations:
    • Within the 48 contiguous states and the District of Columbia, or within the State of Alaska, and remains within 10 miles of the point of departure;
    • Over any island, or within three nautical miles of the coastline of any island, in the Hawaii ADIZ; or
    • Associated with any ADIZ other than the Contiguous U.S. ADIZ, when the aircraft true airspeed is less than 180 knots
  • Authorizations to deviate from the requirements of Part 99 may also be granted by the ARTCC, on a local basis, for some operations associated with an ADIZ
  • An air filed VFR Flight Plan makes an aircraft subject to interception for positive identification when entering an ADIZ. Pilots are, therefore, urged to file the required DVFR flight plan either in person or by telephone prior to departure
  • Special Security Instructions:
    • Each person operating an aircraft in an ADIZ or Defense Area must, in addition to the applicable rules of part 99, comply with special security instructions issued by the Administrator in the interest of national security, pursuant to agreement between the FAA and the Department of Defense, or between the FAA and a U.S. Federal security or intelligence agency
    • Defense Area means any airspace of the contiguous United States that is not an ADIZ in which the control of aircraft is required for reasons of national security
  • Emergency Security Control of Air Traffic (ESCAT)
    • During defense emergency or air defense emergency conditions, additional special security instructions may be issued in accordance with 32 CFR 245 Plan for the Emergency Security Control of Air Traffic (ESCAT)
    • Under the provisions of 32 CFR 245, the military will direct the action to be taken in regard to landing, grounding, diversion, or dispersal of aircraft and the control of air navigation aids in the defense of the U.S. during emergency conditions
    • At the time a portion or all of ESCAT is implemented, ATC facilities will broadcast appropriate instructions received from the Air Traffic Control System Command Center (ATCSCC) over available ATC frequencies. Depending on instructions received from the ATCSCC, VFR flights may be directed to land at the nearest available airport, and IFR flights will be expected to proceed as directed by ATC
    • Pilots on the ground may be required to file a flight plan and obtain an approval (through FAA) prior to conducting flight operation
    • In view of the above, all pilots should monitor an ATC or FSS frequency at all times while conducting flight operations

Visual Warning System (VWS)

  • The VWS signal consists of highly-focused red and green colored laser lights designed to illuminate in an alternating red and green signal pattern
  • These lasers may be directed at specific aircraft suspected of making unauthorized entry into the Washington, DC Special Flight Rules Area (DC SFRA) proceeding on a heading or flight path that may be interpreted as a threat or that operate contrary to the operating rules for the DC SFRA
  • The beam is neither hazardous to the eyes of pilots/aircrew or passengers, regardless of altitude or distance from the source nor will the beam affect aircraft systems
    • If you are communicating with ATC, and this signal is directed at your aircraft, you are required to contact ATC and advise that you are being illuminated by a visual warning system
    • If this signal is directed at you, and you are not communicating with ATC, you are advised to turn to the most direct heading away from the center of the DC SFRA as soon as possible
      • Immediately contact ATC on an appropriate frequency, VHF Guard 121.5 or UHF Guard 243.0, and provide your aircraft identification, position, and nature of the flight
      • Failure to follow these procedures may result in interception by military aircraft
      • Further noncompliance with interceptor aircraft or ATC may result in the use of force
    • Pilots planning to operate aircraft in or near the DC SFRA are to familiarize themselves with aircraft intercept procedures
      • This information applies to all aircraft operating within the DC SFRA including DOD, Law Enforcement, and aircraft engaged in aeromedical operations and does not change procedures established for reporting unauthorized laser illumination as published in FAA Advisory Circulars and Notices

Emergency Airborne Inspection of Other Aircraft:

  • Providing airborne assistance to another aircraft may involve flying in very close proximity to that aircraft
    • Most pilots receive little, if any, formal training or instruction in this type of flying activity
    • Close proximity flying without sufficient time to plan (i.e., in an emergency situation), coupled with the stress involved in a perceived emergency can be hazardous
  • The pilot in the best position to assess the situation should take the responsibility of coordinating the airborne intercept and inspection, and take into account the unique flight characteristics and differences of the category(s) of aircraft involved
  • Some of the safety considerations are:
    • Area, direction and speed of the intercept;
    • Aerodynamic effects (i.e., rotorcraft down-wash);
    • Minimum safe separation distances;
    • Communications requirements, lost communications procedures, coordination with ATC;
    • Suitability of diverting the distressed aircraft to the nearest safe airport; and
    • Emergency actions to terminate the intercept
  • Close proximity, inflight inspection of another aircraft is uniquely hazardous
    • The pilot−in− command of the aircraft experiencing the problem/emergency must not relinquish control of the situation and/or jeopardize the safety of their aircraft
    • The maneuver must be accomplished with minimum risk to both aircraft

Conclusion:

  • If you are intercepted by a U.S. Military or law enforcement aircraft, immediately:
    • Adhere to instructions relayed through the use of visual devices, visual signals, and radio communications from the intercepting aircraft
    • Attempt to communicate with the intercepting aircraft and/or ATC on the emergency frequency 121.5/243.0 MHz, giving the identity and position of your aircraft and the nature of the flight
    • If equipped with a transponder, squawk Mode 3/A code 7700, unless otherwise instructed by ATC
    • If any instructions received by radio from any sources conflict with those given by the intercepting aircraft by visual or radio signals, request clarification while continuing to comply with the instructions given by the intercepting aircraft until positively released
  • Additional national security regulations are covered within Part 99 of the Federal Aviation Regulations
  • For more details about the VWS, check out http://www.faasafety.gov/VisualWarningSystem/VisualWarning.htm

References: