C. Flight Plan (F-PLN) Display There are four F-PLN configurations for which data are transmitted: ACTIVE, SECONDARY, TEMPORARY and the dashed F-PLN. These configurations are transmitted only for ARC, ROSE-NAV or PLAN mode. The display rules for each configuration according to the mode selection are presented in the following paragraphs with in addition two particular flight plan revisions: Abeam/Radial vectors and Direct To (DIR TO)/Intercept display. However, the following general rules apply to all configurations:
-All idents and symbols associated with a terminal area procedure except for the last waypoint in a departure or the first waypoint in an arrival are not transmitted if an enroute range is selected, unless the waypoint is the active waypoint or the MRP. The origin and destination waypoints are displayed.
-If there are no flight plan legs, the corresponding flight plan vectors are not transmitted. For example if the flight plan is the default flight plan (below), no vectors are transmitted. Default flight plan: Present Position (PPOS)
F-PLN Discontinuity End of F-PLN
-A flight plan leg is considered to lie within the edit area for transmission if the origin and/or termination of the leg lies within the edit area or any portion of the leg passes through the edit area. Exceptions may be noted herein.
(1) ACTIVE flight plan The ACTIVE flight plan display may consist of the primary and alternate flight plans, missed approach, offset path, and engine-out SID. These segments are presented in the following paragraphs.
(a) Primary flight plan
1 General display rules
_ The ACTIVE primary flight plan vectors are transmitted for those legs which lie within the defined edit area under the conditions noted below:
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If ARC or ROSE-NAV mode is selected, these vectors are always transmitted.
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If PLAN mode is selected these vectors are always transmitted except in the following case: If a secondary page is displayed on the onside MCDU and the conditions necessary for SECONDARY flight plan sequencing are not satisfied, the ACTIVE primary flight plan vectors are not transmitted. In this case the SECONDARY flight plan vectors are displayed.
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Pre-Nav mode engagement path If NAV mode is armed and the current A/C track is such that it intercepts the active leg, these vectors are transmitted and a curved path capture to the active leg is drawn in solid lines and is dynamically updated. (Ref. Fig. 006)
Leg transitions The FM computes the entry transition onto the active leg and the exit transition off of the active leg for display on the ND. The active waypoint is still displayed although the transition path may not pass directly over the waypoint. The FM computes a next course capture, with a 45-degree intercept (if necessary), onto an AF leg. When an overshoot is forecast between two fixed path legs, the path will be contiguous. If the third leg is a VX or CX leg (excluding CF), the FM also computes the transition from the next leg to the third leg for display on the ND. Turn direction symbols, overfly symbols, and other types of downpath lateral trends are not required for display on the ND. If the active leg is sufficiently short such that the entry transition and exit transition overlap (i.e FISH discon), the entry transition is removed from display as soon as the A/C has sequenced from that transition segment.
Active leg segments As discussed in a preceding paragraph (and excluding any discussion of HX and PF legs), the active leg may be composed of up to 3 distinct segments: the entry transition, the leg, and the exit transition. For the purpose of avoiding EFIS shifting, the FM edits each segment separately before transmitting the segment as background data. For example, if the aircraft is flying a long active leg and the entry transition has sequenced out of the edit area, this entry transition is no longer sent as background data to the ND.
Long leg distortion Vectors are displayed on the ND assuming a simplified earth model. For long great circle path legs, the display is distorted due to this simplified earth model assumption.
Flight Plan Examples
Figure 006
(b)
Alternate flight plan The ACTIVE alternate flight plan vectors are transmitted for those legs which lie within the defined edit area under the conditions noted below:
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If ARC or ROSE-NAV mode is selected these vectors are transmitted if the alternate flight plan is displayed on the onside MCDU.
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If PLAN mode is selected these vectors are transmitted if an alternate flight plan waypoint is the MRP.
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