(2) Tuned navaids If a navaid (see list below) is being tuned for MCDU display on the RAD NAV page, and it is within the defined edit area, the tuned navaid symbol is transmitted. The navaids being tuned on both the onside and offside FMGCs are transmitted. The navaid types that may be tuned are listed below.
 TUNED NAVAID
 -DME only
 -TACAN
 -VOR only
 -VORTAC
 -Collocated VOR/DME
 -
Non-collocated VOR/DME

 -
Non-collocated VOR/TAC

 -ADF (NDB)
 NOTE : For ILS tuned navaid, there is no tuned navaid symbol
____
 transmitted to the EFIS (for de-cluttering purposes).

 In case of manual tuning through Radio Management Panel (RMP) control (in NAV mode) the tuned navaid symbol of the selected navaid, if it is within the defined edit area, is also transmitted by each FMGC to the EFIS. If the tuned navaid is a flight plan waypoint (excluding the FROM waypoint) which has constraints associated with it and if the waypoint CSTR pushbutton switch option is selected, then constraints data are transmitted with the tuned navaid identifier.
 (3) Holding patterns If a holding pattern exists in the ACTIVE primary or alternate or TEMPORARY or SECONDARY flight plan, the holding pattern symbol is transmitted under the following conditions:
 -
The corresponding flight plan is being transmitted

 -
The holding pattern fix is within the defined edit area

 -
The range selection is enroute (320 or 160 NM) or the range selection is terminal (10, 20, 40 or 80 NM) and the holding pattern is not the active or next leg.

 If the range selection is terminal and the holding pattern is the active or next leg in the ACTIVE primary F-PLN and the entry into the holding pattern is determined to be a direct entry, then the computed holding pattern is displayed with no entry transition.

 If the range selection is terminal and the holding pattern is the active or next leg in the ACTIVE primary F-PLN and the entry is determined to be a teardrop or parallel entry, the entry transition is displayed. For HF legs, only the entry transition is shown: for HA or HM legs, the entry transition and the computed holding pattern are displayed until the aircraft crosses the fix if it is predicted that the holding will be flown upon crossing the fix. Otherwise only the entry is displayed. If the range selection is terminal and the holding pattern is the active or next leg in the SECONDARY or TEMPORARY F-PLN, then the computed holding pattern is displayed with no entry transition. Holding pattern vectors are not displayed for the alternate F-PLN. As long as the hold is not the active leg but is the next leg and range selection is terminal, the displayed holding pattern size is computed with a 210 Kts CAS value if predictions are not available or the predicted hold speed otherwise. As soon as the hold is the active leg, the hold is recomputed with the present aircraft CAS value at each fix overfly. While creating an HM and before inserting it, a temporary holding pattern is computed and displayed under the above conditions by using a default 210 Kts CAS value. If the active leg is an Hx and that hold has been modified, the original hold is displayed until the holding fix is crossed. Then the new hold with its entry transition (if any), replaces it on ND.
 (4) Procedure turns If a procedure turn exists in the ACTIVE primary or alternate or TEMPORARY or SECONDARY flight plan, the procedure turn symbol is transmitted under the following conditions:
 -
The corresponding flight plan is being transmitted

 -
The procedure turn fix is within the defined edit area

 -
The range selection is enroute or the range selection is terminal

 and the procedure turn is not the active or next leg. If the terminal area range is selected and the procedure turn is the active or next leg in the ACTIVE primary F-PLN, the calculated path of the procedure turn is transmitted using the present aircraft CAS value. If the terminal area range is selected and the procedure turn is the active or next leg in the SECONDARY or TEMPORARY F-PLN, the calculated path of the procedure turn is transmitted using the default speed of 210 CAS. Procedure turn vectors are not displayed for the alternate F-PLN.

 E. Pushbutton Switch Options Each FCU EFIS control panel has five pushbutton switches which allow selection of various display options. When any of these options has been selected and all of the selected facilities are not displayed (buffer full) a message is displayed on the ND. (This message is generated by the Display Management Computer (DMC)).
 (1)
 Waypoints (WPT) When the WPT pushbutton switch option is selected, all waypoints in the NAV data base and all stored waypoints that meet the following criteria are transmitted as map background data.
　
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