AIM 8/15/19  1/30/20 7/16/20  e. If operating on an IFR flight plan to an airport with a functioning control tower, the flight plan is automatically closed upon landing. f. If operating on an IFR flight plan to an airport where there is no functioning control tower, the pilot must initiate cancellation of the IFR flight plan. This can be done after landing if there is a functioning FSS or other means of direct communications with ATC. In the event there is no FSS and/or air/ground communications with ATC is not possible below a certain altitude, the pilot should, weather conditions permitting, cancel the IFR flight plan while still airborne and able to communicate with ATC by radio. This will not only save the time and expense of canceling the flight plan by telephone but will quickly release the airspace for use by other aircraft. 5 − 1 − 16. RNAV and RNP Operations a. During the pre − flight planning phase the availability of the navigation infrastructure required for the intended operation, including any non − RNAV contingencies, must be confirmed for the period of intended operation. Availability of the onboard navigation equipment necessary for the route to be flown must be confirmed. b. If a pilot determines a specified RNP level cannot be achieved, revise the route or delay the operation until appropriate RNP level can be ensured. c. The onboard navigation database must be current and appropriate for the region of intended operation and must include the navigation aids, waypoints, and coded terminal airspace procedures for the departure, arrival and alternate airfields. d. During system initialization, pilots of aircraft equipped with a Flight Management System or other RNAV − certified system, must confirm that the navigation database is current, and verify that the aircraft position has been entered correctly. Flight crews should crosscheck the cleared flight plan against charts or other applicable resources, as well as the navigation system textual display and the aircraft map display. This process includes confirmation of the waypoints sequence, reasonableness of track angles and distances, any altitude or speed constraints, and identification of fly − by or fly − over waypoints. A procedure must not be used if validity of the navigation database is in doubt. e. Prior to commencing takeoff, the flight crew must verify that the RNAV system is operating correctly and the correct airport and runway data have been loaded. f. During the pre − flight planning phase RAIM prediction must be performed if TSO − C129() equipment is used to solely satisfy the RNAV and RNP requirement. GPS RAIM availability must be confirmed for the intended route of flight (route and time) using current GPS satellite information. In the event of a predicted, continuous loss of RAIM of more than five (5) minutes for any part of the intended flight, the flight should be delayed, canceled, or re − routed where RAIM requirements can be met. Operators may satisfy the predictive RAIM require- ment through any one of the following methods: 1. Operators may monitor the status of each satellite in its plane/slot position, by accounting for the latest GPS constellation status (for example, NOTAMs or NANUs), and compute RAIM availabil- ity using model − specific RAIM prediction software; 2. Operators may use the Service Availability Prediction Tool (SAPT) on the FAA en route and terminal RAIM prediction website; 3. Operators may contact a Flight Service Station to obtain non − precision approach RAIM; 4. Operators  may use a third party interface, incorporating FAA/VOLPE RAIM prediction data without altering performance values, to predict RAIM outages for the aircraft’s predicted flight path and times; 5. Operators may use the receiver’s installed RAIM prediction capability (for TSO − C129a/Class A1/B1/C1 equipment) to provide non − precision approach RAIM, accounting for the latest GPS constellation status (for example, NOTAMs or NANUs). Receiver non − precision approach RAIM should be checked at airports spaced at intervals not to exceed 60 NM along the RNAV 1 procedure’s flight track. “Terminal” or “Approach” RAIM must be available at the ETA over each airport checked; or, 6. Operators not using model − specific software or FAA/VOLPE RAIM data will need FAA operational approval. NOTE − If TSO C145/C146 equipment is used to satisfy the RNAV and RNP requirement, the pilot/operator need not perform the prediction if WAAS coverage is confirmed to be 5 − 1 − 31 Preflight