AIM 8/15/19  Section 4. ATC Clearances and Aircraft Separation 4 − 4 − 1. Clearance 4 − 4 − 2. Clearance Prefix 4 − 4 − 3. Clearance Items a. A clearance issued by ATC is predicated on known traffic and known physical airport conditions. An ATC clearance means an authorization by ATC, for the purpose of preventing collision between known aircraft, for an aircraft to proceed under specified conditions within controlled airspace. IT IS NOT AUTHORIZATION FOR A PILOT TO DEVIATE FROM ANY RULE, REGULATION, OR MINIMUM ALTITUDE NOR TO CONDUCT UNSAFE OPERATION OF THE AIRCRAFT. b. 14 CFR Section 91.3(a) states: “The pilot − in − command of an aircraft is directly responsible for, and is the final authority as to, the operation of that aircraft.” If ATC issues a clearance that would cause a pilot to deviate from a rule or regulation, or in the pilot’s opinion, would place the aircraft in jeopardy, IT IS THE PILOT’S RESPONSIBILITY TO REQUEST AN AMENDED CLEARANCE. Simi- larly, if a pilot prefers to follow a different course of action, such as make a 360 degree turn for spacing to follow traffic when established in a landing or approach sequence, land on a different runway, takeoff from a different intersection, takeoff from the threshold instead of an intersection, or delay operation, THE PILOT IS EXPECTED TO INFORM ATC ACCORDINGLY. When the pilot requests a different course of action, however, the pilot is expected to cooperate so as to preclude disruption of traffic flow or creation of conflicting patterns. The pilot is also expected to use the appropriate aircraft call sign to acknowledge all ATC clearances, frequency changes, or advisory information. c. Each pilot who deviates from an ATC clearance in response to a Traffic Alert and Collision Avoidance System resolution advisory must notify ATC of that deviation as soon as possible. Pilot/Controller Glossary Term −  Traffic Alert and Collision Avoidance System. d. When weather conditions permit, during the time an IFR flight is operating, it is the direct responsibility of the pilot to avoid other aircraft since VFR flights may be operating in the same area without the knowledge of ATC. Traffic clearances 1. Clearances are normally issued for the altitude or flight level and route filed by the pilot. However, due to traffic conditions, it is frequently necessary for ATC to specify an altitude or flight level b. Departure Procedure. Headings to fly and altitude restrictions may be issued to separate a departure from other air traffic in the terminal area. Where the volume of traffic warrants, DPs have been developed. AIM, Paragraph 5 − 2 − 5, Abbreviated IFR Departure Clearance (Cleared. . .as Filed) Procedures AIM, Paragraph 5 − 2 − 9 , Instrument Departure Procedures (DP)  − Obstacle Departure Procedures (ODP) and Standard Instrument Departures (SID) ATC clearances normally contain the following: a. Clearance Limit. The traffic clearance issued prior to departure will normally authorize flight to the airport of intended landing. Many airports and associated NAVAIDs are collocated with the same name and/or identifier, so care should be exercised to ensure a clear understanding of the clearance limit. When the clearance limit is the airport of intended landing, the clearance should contain the airport name followed by the word “airport.” Under certain conditions, a clearance limit may be a NAVAID or other fix. When the clearance limit is a NAVAID, intersection, or waypoint and the type is known, the clearance should contain type. Under certain conditions, at some locations a short − range clearance procedure is utilized whereby a clearance is issued to a fix within or just outside of the terminal area and pilots are advised of the frequency on which they will receive the long − range clearance direct from the center controller. provide standard separation only between IFR flights. A clearance, control information, or a response to a request for information originated by an ATC facility and relayed to the pilot through an air − to − ground communication station will be prefixed by “ATC clears,” “ATC advises,” or “ATC requests.” c. Route of Flight. REFERENCE − REFERENCE − 4 − 4 − 1 ATC Clearances and Aircraft Separation