-
If navigation accuracy is HIGH and NAV mode is not GPS/INERTIAL with GPS option active, the GPS PRIMARY LOST message is displayed at transition to APPR Flight phase.

 -
If NAV accuracy is LOW, "NAV ACCUR DOWNGRAD" message is displayed

 at transition to APPR Flight area. More over, the NAV ACCUR UPGRAD message is never displayed when the aircraft is in APPR Flight phase. This does not affect the navigation accuracy logic (HIGH - LOW switching). The NAV ACCUR UPGRAD and NAV ACCUR DOWNGRAD messages are inhibited when navigation mode is GPS/INERTIAL. When not inhibited, these messages will only be displayed after a confirmation time of 10 seconds. In all cases, GPS confidence level messages have a higher priority than class of navigation messages. GPS PRIMARY related display and messages (Ref. Fig. 012) When GPS mode is active, GPS PRIMARY state is displayed on CDU PROGRESS page. When GPS mode is not active, the current aircraft symbol is displayed on the ND with GPS PRIMARY LOST message displayed below. The GPS PRIMARY message is not displayed on the CDU PROGRESS page. The "GPS IS DESELECTED" message, is displayed on the MCDU only, to indicate that GPS has been deselected. This message is displayed when the aircraft is at 80 NM from T/D or when APPR Phase gets active.
 C. Radio Navigation Tuning
 (1) General
 (Ref. Fig. 013)
 The navaid selection includes selection of:

 -VOR (frequency/course) and DME for display
 -ILS (frequency/LOC course) R - NDB (frequency/BFO) R - MLS (channel).
 Radio tuning may be performed via three different ways which are:
 -Radio Management Panel (RMP) selection
 -manual selection through the MCDU
 -automatic selection (in FMGC software). The priority order of selection is as follows:
 -
manual selection through the RMP

 -
manual selection through the MCDU cannot override RMP selection

 -automatic selection cannot override manual selection through the MCDU and RMP.
 (2) RMP selection (Ref. 23-81-00) (Ref. Fig. 014) The FMGC recognizes the RMP tuning when the RMP (1 or 2) NAV CONTROL discrete is set to the open state. When this occurs, neither the system nor the pilot can tune the radio
R frequencies on either side of the RAD NAV pages.

 ND Displays
 Figure 012

 Radio Navigation Architecture
 Figure 013

R RMP Selection Figure 014
R 1EFF : 106-149, 151-199, 211-299, 301-399, 1 22-72-00Page 31 1401-499, 1Config-2 Aug 01/05 1 1 1CES 1

 (3) Manual selection through MCDU (Ref. Fig. 015, 016) Manual selection includes the following definition:
 -VOR tuning
 -ILS tuning R - MLS tuning
 -NDB tuning.
 A station manually tuned cannot be overridden by an automatic tuning.
 When the system passes in PREFLIGHT phase, all the previously tuned
 navaids are untuned.

 (a)
 VOR tuning At any time, the pilot can manually tune for display a VOR station by ident or frequency on the RADIO NAV page. In addition on the RAD NAV page the course to a VOR can be selected. When a selected VOR is a VOR/DME (or VORTAC) station, the DME (or TACAN) is also tuned as "displayed frequency".

 (b)
 ILS tuning At any time, the pilot can manually tune an ILS station by ident or frequency on the RADIO NAV page. ILS ident and frequency are displayed in field 3L. ILS course is displayed in field 4L.

 (c)
 ADF tuning

 (Ref. Fig. 017) R None, one or two ADFs are installed in the aircraft. This is R defined by activation of an option in OPC file.
 When only one ADF is installed it is considered as ADF number 1.
 The pilot can tune the ADFs by ident or frequency on the RADIO
 NAV page.
 Fields 5L and 6L correspond to ADF1, fields 5R and 6R correspond
 to ADF2.

R Fields are blanked when corresponding ADF is not installed. R
 (4) Automatic selection In the following, the RMP has no control of the navigation radios except if specifically said.
 (a) VOR tuning The tuning of the VOR follows 7 rules, hierarchically defined from 1 to 7. If a rule is satisfied, the navaid defined by this rule is selected, disregarding the rules whose number is greater.
 -Rule 1: VOR has been manually tuned by the pilot.

 Manual Selection Through RADIO NAV Page and PROG Page
 Figure 015

 Manual Selection Through MCDU on ND
 Figure 016

 RADIO NAV Page with 2nd ADF option activated MLS option not activated.
 Figure 017

 -
Rule 2: RNAV, VOR and VOR/DME approach: if a RNAV, VOR or VOR/DME approach is selected and one fix of the approach is the TO waypoint, the specified navaid is tuned.
　
中國航空網 www.k6050.com
航空翻譯 www.aviation.cn
本文鏈接地址：A320飛機維護手冊 AMM AUTO FLIGHT 自動飛行3(85)