ORDER 7110.49D 2/22/80 Initiated by: AAT-320 SUBJECT: UNLAWFUL INTERFERENCE - HIJACK/BOMB (THREAT) ABOARD AIRCRAFT - PROCEDURES AND COVERT SIGNALS 1. PURPOSE. This order prescribes the signals which may be used by pilots experiencing certain types of unlawful interference (i.e., hijack/bomb [threat] aboard) to make their situation known to air traffic control (ATC) and outlines the required dissemination of these signals to pilots who may have a need for the information. 2. DISTRIBUTION. This order is distributed to Branch level and above in Washington Air Traffic, Flight Operations, and Civil Aviation Security; to Branch level and above in Regional Air Traffic, Flight Standards, and Air Transportation Security Divisions; to all supervisors in the regional Communications Control Center; to all Air Traffic Field Offices, General Aviation, Air Carrier, and Flight Standards District Offices, Aeronautical Quality Assurance Field Offices, and Flight Standards International Field Offices; and Air Transportation Security Field Offices. 3. CANCELLATION. Order 7110.49C, Unlawful Interference - Hijack/Bomb (Threat) Aboard Aircraft - Procedures and Covert Signals, is canceled. 4. EFFECTIVE DATE. This order is effective May 1, 1980. 5. GENERAL. The material contained herein, while not considered national security information requiring classification, shall be handled as privileged information and shall be disseminated to operators and ATC specialists on a strict "need-to-know" basis. LOCAL REPRODUCTION IS NOT AUTHORIZED. The procedures were developed for covert application solely within U.S. airspace. Designated representatives of the Department of Justice and airlines have been made familiar with the procedures and pilot signals herein. Inquiries regarding information contained herein from the above sources, as well as those official requests from International Civil Aviation Organization contracting states, should be referred to the Director, Air Traffic Service, AAT-1. 6. PROCEDURES. a. When possible, the pilot of an aircraft experiencing unlawful interference (i.e., hijack/bomb [threat] aboard) should transmit a description of the predicament and any requests for assistance to air traffic control in the clear. Air traffic controllers shall respond to all requests, comply if possible, and notify the proper authorities. Circumstances may prevent radio transmissions in the clear and will necessitate use of covert signaling either by voice or by transponder when radar service is available. NOTE: There are areas where radar service is not available and radio is the only communication method. In these areas, ATC will advise when radar service is terminated. The following actions include messages transmitted in the clear and transmitted covertly either by voice or by transponder signal. (1) SITUATION. Am being hijacked/subjected to unlawful interference. (a) PILOT MESSAGE (Overt): Same as 6(1) above. 1 When an in-the-clear radio transmission of unlawful interference is received, controllers shall assign Code 7500 to the aircraft (this does not preclude a subsequent change to Code 7700 by the pilot, if necessary). 2 When a radio transmission is received indicating the possibility of unlawful interference without accompanying Mode 3/A, Code 7500 transmission, controllers shall assign Code 7500 to the aircraft. Should the pilot question such assignment, or otherwise indicate that a clear condition exists, the controller can then determine the specific nature of the situation and be in a better position to make subsequent judgments regarding the need for notification, clearance and other actions. Should the pilot acknowledge assignment of Code 7500 without further communication, or fail to acknowledge or communicate further, the controller shall assume that the flight is being subjected to unlawful interference and act accordingly. 3 Following initiation of a hijacking, the pilot may communicate or respond to routine controller transmissions by using the word "TRIP" following the aircraft designator (Trans World TRIP 419 or United TRIP 517). This indicates the pilot is unable to communicate in the clear (the hijacker is probably in the cockpit). In such cases, the controller should respond using "TRIP" in the flight designator as in the example above. During an incident, the Civil Aviation Security Command Center in FAA Headquarters may request that the controller use the "TRIP" designator in routine communication with the aircraft as a query to the pilot whether clear communication is possible. Should this action result in a response from the pilot that communication in the clear is possible, the Command Center may request the controller to pass information to the pilot or solicit information from the pilot. Should the controller transmission using "TRIP" result in a pilot response also using the "TRIP" designator, the controller should limit transmissions to the aircraft to essential air traffic control functions and should not communicate with the aircraft about the incident in progress (reference paragraph 6(1)(a)4 below). 4 When a controller knows or believes that an aircraft is being subjected to unlawful interference, no reference shall be made in ATC air-ground communications to the nature of the emergency unless it has first been referred to in communications from the aircraft involved or unless the pilot is transmitting in the clear and it is certain that such reference will not aggravate the situation. (b) PILOT SIGNAL (COVERT): Set transponder to Mode 3/A, Code 7500. When unable to change the transponder setting or when not under radar service, transmit a radio message which includes the phrase "(aircraft call sign) transponder seven five zero zero." 1 Controllers shall acknowledge receipt of beacon Code 7500 by transmitting "(aircraft call sign) (name of facility) verify squawking 7500." An affirmative reply from the pilot indicates confirmation and proper authorities shall be notified by the receiving facility. 2 Should the pilot believe it unwise to use the phrase "(aircraft call sign) transponder seven five zero zero," he may use the "TRIP" designator described in paragraph 6(1)(a) above. In such cases, the controller should follow the procedures outlined in paragraph 6(1)(a)3. 3 Controllers shall honor clearance requests insofar as possible. (2) SITUATION IN THE AIR: Situation grave; imminent danger is anticipated; require immediate assistance. (a) PILOT MESSAGE (Overt): Same as above. Same as 6(1)(a)1 thru 2 except Code 7700 should be assigned. (b) PILOT SIGNAL (Covert): After using Code 7500, change the transponder to Code 7700. When unable to change the transponder setting or when not under radar service, transmit "(aircraft call sign) transponder seven seven zero zero." 1 Before changing from Code 7500 to Code 7700, pilots should remain on 7500 for at least 3 minutes or until a confirmation of Code 7500 has been received from the controller, whichever is sooner. Controllers shall acknowledge receipt of Code 7700 by transmitting "(aircraft call sign) (name of facility) now reading you on transponder seven seven zero zero." 2 Same as 6(1)(b)2 above. 3 Aircraft switching from Code 7500 to Code 7700 that are not in radio contact with the ground will be considered by ATC to have an in-flight emergency (in addition to condition of unlawful interference) and the appropriate emergency procedures shall be followed. In these cases, notification of concerned authorities shall include information that the aircraft displayed the unlawful interference (i.e., hijack/bomb [threat] aboard) code as well as the emergency code. (3) SITUATION ON THE GROUND: Situation grave; want armed intervention and aircraft immobilized. (a) PILOT MESSAGE (Overt). Same as 6(3) above. (b) PILOT SIGNAL (Covert): Leave full flaps down after landing or lower full flaps while on the ground. (4) SITUATION ON THE GROUND: Leave alone - do not intervene. (a) PILOT MESSAGE (Overt). Same as 6(4) above. (b) PILOT SIGNAL (Covert): Retract flaps after landing. NOTE: Pilots who retract flaps after squawking Code 7700 should return to Code 7500 and remain on Code 7500 for the next leg of the hijacked flight unless the situation changes again. The pilot may transmit "(aircraft call sign) back on seven five zero zero" to emphasize the fact that intervention is no longer desired. b. Air Carrier District Offices and Flight Standards District Offices shall ensure that Part 121 air carrier and commercial operator pilots are trained and knowledgeable about unlawful interference (i.e., hijack/bomb [threat] aboard) procedures and covert signals. General Aviation District Offices and Air Transportation Security Field Offices will be responsible for disseminating this information to general aviation and air taxi pilots. Flight Standards field offices having responsibility for Part 129 foreign air carriers will ensure that this information is disseminated to those operators. /s/ Langhorne Bond Administrator FOR OFFICIAL USE ONLY - Public Availability to be determined under 5 U.S.C. 552.