Go Around: FMS Procedures
A320/A330 Quick Study Guide
PURPOSE AND SCOPE
This QSG (Quick Study Guide) takes an in-depth look at the go around maneuver from the perspective of the FMS, using an example to describe all mode changes, flight phase sequencing and the different color codes used by Airbus to present information. Effectively programming the “box” prior to any approach and knowing the different possibilities available will greatly reduce crew workload in case of go around while enhancing situation awareness.
INITIAL DATA
Our flight destination is LEVC, and at present time we are stabilized on final approach ILS RWY30, passing 500’ AAL and waiting for visual contact. The missed approach procedure is:
Climb on runway heading to 720’, then turn right direct to SGO NDB climbing to 3000’ and hold.
Alternate is LEBL, and we have been thoughtful enough to key-in the complete route (via SAURA-ASTEK waypoints) as well as the expected STAR and ILS approach to RWY07L. This is a very good practice to avoid excessive workload in case of diversion and also to have realistic fuel predictions.
So, this is what our PFD, ND and MCDU look like:
Go Around: FMS Procedures
A320/A330 Quick Study Guide
But if we could stretch the MCDU screen to see the complete F-PLN, this is what we’d see:
1 – ACTIVE F.PLN (from waypoint: PND to waypoint: LEVC30)
2 - MISSED APP PROCEDURE (climb on RWY HDG to 720’, then turn right direct SGO climbing 3000’and hold)
3 - DESTINATION AERODORME
4 – F-PLN TO ALTERNATE LEBL
5 - ILS APP RWY 07L LEBL
6 - MISSED APP PROCEDURE ILS RWY 07L LEBL 7 – DESTINATION (LEVC30) F -PL N T O D EST IN AT IO N F -PL N T O AL T ER N A T E
Go Around: FMS Procedures
A320/A330 Quick Study Guide
1 – ACTIVE FLIGHT PLAN
This part of the F-PLN is color-coded in green (except for the TO waypoint in white), and is the only part of the flight plan that is automatically followed by the AFS, and where
predictions are available. Also, green waypoints are the only ones available to fly DIRECT-TO.
2 - MISSED APP PROCEDURE
Color-coded cyan, is still part of the flight plan to destination, although for the time being it is not active but ‘armed’, so
NAVigation to those waypoints is not available.
The last waypoint of the missed approach procedure marks the end of the flight plan to destination:
3 – DESTINATION AERODROME
Automatically added after the F-PLN to destination for the purpose of auto-stringing the previously flown approach at the end of the flight plan in case of go around. Color-coded
cyan.
4 and 5 – F-PLN TO ALTERNATE LEBL INCLUDING ILS APP RWY 07L
During approach preparation, it is always a good practice to prepare the route, STAR and approach to alternate. FMS will store it as a different flight plan, called ALTN F-PLN and it is color-coded cyan.
6 - MISSED APP PROCEDURE DE LA APP ILS RWY 07L LEBL
Anytime an approach is loaded into the system, the missed approach procedure is also incorporated at the end. Color-coded cyan.
7 – DESTINATION (LEVC30)
While in F-PLN page, the last line of the display always presents the destination aerodrome, ETA, distance and EFOB. Color-coded white.
Go Around: FMS Procedures
A320/A330 Quick Study Guide
GOING AROUND
Reaching minimums we have no visual contact, so a go around is executed. PFD, ND and MCDU change to:
FMA indicates TOGA thrust, maximum gradient climb (SRS) and NAV mode engages. Additionally, “TOGA” signal is received by the FMS and flight phase is sequenced from “approach” to “go around”.
Looking at the MCDU, the missed approach procedure is now color-coded green, indicating that is part of the active flight plan and will be automatically followed by the AFS.
NOTE: some old A320/A330s and simulators (i. e. HK-04 and HK-05) will not automatically engage NAV mode, but instead, GA TRK mode is engaged. In this situation, push HDG knob (“manage navigation”), to manually arm and activate NAV mode.
Go Around: FMS Procedures
A320/A330 Quick Study Guide
Once above 720’, a right turn is made to SGO, and passing 1500’, thrust is reduced to CLB and vertical mode reverts to OPEN CLB.
It must be noted that managed climb mode is not available and therefore constraints -if any- will not be honored.
Continue climbing to 3000’, accelerating and cleaning up while flying to SGO to enter the holding pattern. While in go around phase, the target speed is green dot and no predictions are available:
Go Around: FMS Procedures
A320/A330 Quick Study Guide
Now let’s see what the flight plans looks like after triggering the go around phase:
1 – ACTIVE FLIGHT PLAN (from waypoint: 720’->. To waypoint: SGO) includes the complete missed approach procedure
2 - APP PROCEDURE LEVC ILS RWY30, automatically strung back into the flight plan at the end of the missed approach procedure, as part of the active flight plan. It will not be automatically followed by the AFS as a discontinuity has been created 3 - MISSED APP PROCEDURE
4 - DESTINATION AERODROME
5 - F-PLN TO ALTERNATE LEBL
6 - ILS APP LEBL RWY 07
7 - MISSED APP PROCEDURE ILS RWY 07L LEBL 8 – DESTINATION (LEVC30) F -PL N T O D EST IN AT IO N F -PL N T O AL T ER N A T E
Go Around: FMS Procedures
A320/A330 Quick Study Guide
1 - ACTIVE FLIGHT PLAN: MISSED APP
When go around phase is triggered, the missed approach procedure becomes the active plan.
2 - APP PROCEDURE ILS RWY30
The previously flown approach is automatically strung at the end of the active flight plan, separated from the missed approach procedure by a discontinuity. DIRECT-TO any waypoint is available.
3 - MISSED APP PROCEDURE ILS RWY30
Also added automatically after the ILS approach as part of the flight plan to destination, but NOT part of the active flight plan. Color-coded cyan.
4 to 8 – DESTINATION AERODROME (LEVC) AND ALTN FLIGHT PLAN Remain unchanged.
Go Around: FMS Procedures
A320/A330 Quick Study Guide
ATC reports an improvement in weather conditions, clears to proceed direct to 10 DME VLC VOR and we decide to retry the approach, so all we have to do is DIRECT-TO 10VLC waypoint.
Then, when entering the initial approach area, approach phase has to be manually activated and the new ILS approach is normally flown.
Go Around: FMS Procedures
A320/A330 Quick Study Guide
GOING AROUND: DIVERT
Weather conditions at destination are not improving, so we decide to divert to our alternate LEBL.
Go Around: FMS Procedures
A320/A330 Quick Study Guide
Now our destination is LEBL, our TO waypoint is still SGO, and a discontinuity is generated below.
Go Around: FMS Procedures
A320/A330 Quick Study Guide
Furthermore, FMS has changed from “go around” phase to “climb” phase, with default cruise level FL100 if the distance to the alternate is under 100NM, FL220 if between 100 and 200NM and FL310 if more tan 200NM.
Managed climb speed is ECON CLIMB with cost index 0 (usually limited to 250 Kts below FL100) and all predictions are recalculated for our new destination
Go Around: FMS Procedures
A320/A330 Quick Study Guide
Stretching the MCDU screen once again:
Active flight plan now includes the missed approach procedure as before, but also the complete route + STAR+ ILS approach RWY 07L at our new destination LEBL.
Additionally, the missed approach
procedure is automatically added after the ILS approach (“climb on RWY heading to 3000’ and expect ATC instructions”).
Go Around: FMS Procedures
A320/A330 Quick Study Guide
All we need to do now is DIRECT-TO waypoint SAURA in our MCDU and “manage altitude 22000” in our FCU to fly the selected route to LEBL, climbing FL220 and continue our flight to LEBL according SOPs:
This document is current to FCOM Revision 18 DEC 2012
Go Around: FMS Procedures
A320/A330 Quick Study Guide