Section 5, Chapter 5 - Hijacking & Unlawful Interference

Question 1

What are some instances of hijacking and unlawful interference with aircraft?

Answer 1

• Hijacking: The unlawful seizure or exercise of control of an aircraft by force or threats.
• Unauthorised removal: The unauthorised removal of an aircraft and its subsequent flight.
• Intent to defect: Flight of an aircraft with the intent to defect.
• Escape facilitation: Illegal use of an aircraft to effect the escape of prisoners or special hospital patients.
• Crime and terrorism: The use of aircraft in the furtherance of a crime, including terrorism.

Question 2

What is the policy for ensuring safety during a hijacking incident in UK airspace?

Answer 2

• Safety of the aircraft and its occupants is of prime importance.
• Hijacked aircraft should land as soon as possible, unless directed otherwise by a higher authority.
• Requests from the lawful commander essential for flight safety must be complied with, and no attempts should be made to influence events without the commander’s concurrence.

Question 3

Who coordinates ATC actions during a hijacking incident, and what is their role?

Answer 3

• The Watch Supervisor at the parent ACC acts as the ATC Co-ordinating Authority for the incident until responsibility is assumed by the UK Air Defence Authority.
• The Watch Supervisor supports actions required by the UK Air Defence Authority and coordinates actions with civil/military ATSUs as tactically agreed.
• Overall direction of the incident rests with Government officials acting through the DfT or MoD and the ATC Co-ordinating Authority.
• Controllers’ communications with the hijacked aircraft may be subject to Government instruction, which may include requests to issue instructions not normally considered suitable but ensuring safety is not prejudiced.

Question 4

What are the general ATC operations during an occurrence of unlawful interference with an aircraft?

Answer 4

• Attend promptly to requests by the aircraft involved in unlawful interference.
• Give priority to the aircraft where possible and expedite all phases of the flight, especially safe landing.
• Avoid referencing the special situation in air-ground communications with other aircraft unless the aircraft involved has first referred to it, and it’s reasonable to assume it won’t aggravate the situation.
• Allow reduced separation between aircraft involved if requested by a lawful commander.
• Clear the aircraft to a designated isolated parking position in accordance with local instructions.
• If no designated position is available, clear the aircraft to a position within an area agreed with the Aerodrome Operator.
• Specify the taxi route to the parking position, minimizing security risks to the public, other aircraft, and installations at the aerodrome.

Question 5

How should ATS surveillance systems be used during an occurrence of unlawful interference with an aircraft?

Answer 5

• Monitor flight paths: Controllers should monitor the flight paths of the aircraft and provide adjacent ATC units with information for assistance.
• Verify A7500 code: If the aircraft is transponding on A7500, the controller should attempt to verify the intentional selection of the code without mentioning A7500 directly.
• Phraseology: “(Callsign) confirm you are squawking assigned code (code assigned by ATC that it would otherwise be squawking).”
• Assume unlawful interference: If intentional selection is confirmed or no verification is obtained, assume the aircraft has suffered unlawful interference.
• Use phraseology as a discrete check: The phraseology may also be used as a prompt if A7500 is not being displayed but there is a potential security threat, allowing the pilot to select A7500 if able.

Question 6

What are the procedures for ATC clearances during an occurrence of unlawful interference with an aircraft?

Answer 6

• Continue normal ATC clearances and provide information for safe flight unless directed otherwise by higher authority.
• Withholding ATC clearance: If directed by HM Government, use the following RTF phraseology:
  1. “(Callsign) I am instructed by Her Majesty’s Government to refuse entry into United Kingdom airspace. What are your intentions?”
  2. “(Callsign) I am instructed by Her Majesty’s Government to inform you that landing clearance has been refused for any airfield within the United Kingdom. What are your intentions?”
  3. “(Callsign) I am instructed by Her Majesty’s Government that you are to hold at (location) at (level). Acknowledge.”
  4. Note: If the aircraft is on the ground, the Aerodrome Authority coordinates with HM Government.
• Relaying messages: Adjacent ATC agencies should pass the message verbatim on behalf of the UK.
• Reporting non-compliance: Report the aircraft’s intentions or non-compliance with HM Government instructions to the parent ACC or Aerodrome Authority as soon as possible.
• Provision for normal separation: Maintain normal separation if the aircraft ignores the lack of clearance and inform the parent ACC.
• Handling emergencies: If the aircraft declares an emergency, provide all necessary assistance, including direct routings and landing. The MoD, advised by DfT, NATS, or the Police, may select a diversion destination if needed.

Question 7

What reporting actions should be taken if an aircraft is hijacked and within or planned to enter UK airspace?

Answer 7

• Inform the civil Watch Supervisor at the parent ACC immediately if the aircraft is within, or planned to enter, UK airspace, or if UK interests are likely to be affected.
• European airspace protocol: Hijack incidents and subsequent relevant changes occurring in European airspace will be signaled by the affected State to all other States.
• Refer to Section 6: Follow the detailed reporting actions specified in Section 6 for ATC units.

Question 8

How are hijacked aircraft identified to ATC staff?

Answer 8

Hijacked aircraft are identified by:

• Selection of A7500 on the aircraft’s transponder.
• Declaration of the hijacking on the RTF frequency.

Question 9

What are some indicators of a potential hijack or airborne security situation if A7500 has not been selected or a definitive RTF call received?

Answer 9

Indicators of a potential hijack or airborne security situation include:

• Unauthorised deviation from the cleared flight profile.
• Refusal or inability to comply with ATC instructions (including vectoring) without a good reason.
• Loss of RTF contact associated with flight profile deviation.
• Unauthorised SSR code changes or extended use of IDENT.
• Use of non-standard phraseology by the crew or other covert attempts to highlight the situation (e.g., marked change in voice characteristics).
• Selection of A7600 (RTF failure) or A7700 (emergency), particularly with flight profile deviation.
• Notification from non-official sources (e.g., news agencies).
• Open RTF transmitter from the cockpit.
• Non-ATC related RTF transmission (e.g., political statement).
• Non-specific threat passed via a third party.

Individual events may not alone indicate suspicious activity, but a combination should be considered unusual and appropriate alerting action should be undertaken.