A320 high altitude missed approach
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A320 high altitude missed approach
Quick question.
If you're on approach say at 3000ft and you are instructed to perform a go around, but the published go around altitude for the procedure is 2000ft. Am I correct in saying that you still have to descend to 2000ft while following the missed approach track?
Also to activate the GA TRK, you need to set TOGA temporarily and then back to CLB in this scenario. What would the FMA read?
If you're on approach say at 3000ft and you are instructed to perform a go around, but the published go around altitude for the procedure is 2000ft. Am I correct in saying that you still have to descend to 2000ft while following the missed approach track?
Also to activate the GA TRK, you need to set TOGA temporarily and then back to CLB in this scenario. What would the FMA read?
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I don't think it matters really what aircraft type - we on the 737 are taught to descend to the MAA and follow the track. Eindhoven is a good example.
However, in reality I would query it with ATC. Most likely you would just be re-vectored for a new approach.
However, in reality I would query it with ATC. Most likely you would just be re-vectored for a new approach.
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In the situation described by the OP I'd first stop descent at current altitude and ask ATC for further instructions. in ANY a/c, not only Airbus.
As for the Bus specificalities:
- if I were to discontinue the approach before extending flaps I'd just go for HDG mode laterally and VS vertically.
- after extending flaps - TOGA, then immediately back to CLB detent (to force the FMGS into G/A phase) and "push to level off" to stop climb. Then either NAV to follow Missed App routing or HDG for vectos. Vertically VS to whatever altiitude agreed with ATC.
As for the Bus specificalities:
- if I were to discontinue the approach before extending flaps I'd just go for HDG mode laterally and VS vertically.
- after extending flaps - TOGA, then immediately back to CLB detent (to force the FMGS into G/A phase) and "push to level off" to stop climb. Then either NAV to follow Missed App routing or HDG for vectos. Vertically VS to whatever altiitude agreed with ATC.
Last edited by Stuck_in_an_ATR; 1st Nov 2012 at 12:53.
Ut Sementem Feeceris
This is know as a "discontinued approach". Firstly, THERE IS NO HURRY. You need to think about what you need to achieve and how you're going to achieve it. Selecting TOGA would not be a good idea..... with flap selected you will engage SRS GA TRK with all the associated excitement and in the example you state the missed approach altitude is below so the last thing you want is climb command. Just maintaining current altitude is also not a good idea as you potentially risk compromising separation with departing traffic - think of a multi-runway airport like AMS.
Here's how we do it.....
To discontinue the approach, proceed as follows:
PUSH V/S - this levels the aircraft.
SELECT GREEN DOT SPEED - wind the bug into the barbers pole.
IF G/S IS ARMED PUSH APPR PB (LOC and G/S modes are disengaged)
PNF SELECTS FLAP IN ONE STAGE IF REQUIRED AND REQUESTED BY PF
RETRACT LANDING GEAR IF APPLICABLE
PF USES V/S TO ACHIEVE THE DESIRED ALTITUDE
FLAP RETRACTION ON SCHEDULE (At no time are the thrust levers moved to the TOGA detent)
Note:
As the thrust levers are not set briefly to TOGA detent, flying over, or close to the airport (less than 7 NM) may sequence the Destination waypoint in the FPLN.
In this case select a suitable DIR TO waypoint and reprogram the FMGS.
Where specific speed restrictions exist the configuration and use of selected speed may need to be varied.
A few points to note here. When selecting GN DOT you must wind the bug into the barbers pole on the PFD. i.e. if you're at CONFIG 2 with the pole at 200 knots and you're doing 160 knots selected, you must wind the bug to, say, 215 knots - this is to prevent A/THR reducing thrust if you only selected 195 knots. The idea is to keep the power on and clean up on schedule. The use of V/S to then achieve the desired altitude can take a little while to establish as the centre of lift changes as the flaps retract i.e V/S -300 fpm does nothing UNTIL the wing is clean.
The FLT PLN will dump as you cross the threshold. If you've made a copy in the secondary (always a good idea once you start vectoring), just activate the secondary and you can then tidy it up (perf should be there) and have another go.
Don't rush it, think, monitor.
A4
Here's how we do it.....
To discontinue the approach, proceed as follows:
PUSH V/S - this levels the aircraft.
SELECT GREEN DOT SPEED - wind the bug into the barbers pole.
IF G/S IS ARMED PUSH APPR PB (LOC and G/S modes are disengaged)
PNF SELECTS FLAP IN ONE STAGE IF REQUIRED AND REQUESTED BY PF
RETRACT LANDING GEAR IF APPLICABLE
PF USES V/S TO ACHIEVE THE DESIRED ALTITUDE
FLAP RETRACTION ON SCHEDULE (At no time are the thrust levers moved to the TOGA detent)
Note:
As the thrust levers are not set briefly to TOGA detent, flying over, or close to the airport (less than 7 NM) may sequence the Destination waypoint in the FPLN.
In this case select a suitable DIR TO waypoint and reprogram the FMGS.
Where specific speed restrictions exist the configuration and use of selected speed may need to be varied.
A few points to note here. When selecting GN DOT you must wind the bug into the barbers pole on the PFD. i.e. if you're at CONFIG 2 with the pole at 200 knots and you're doing 160 knots selected, you must wind the bug to, say, 215 knots - this is to prevent A/THR reducing thrust if you only selected 195 knots. The idea is to keep the power on and clean up on schedule. The use of V/S to then achieve the desired altitude can take a little while to establish as the centre of lift changes as the flaps retract i.e V/S -300 fpm does nothing UNTIL the wing is clean.
The FLT PLN will dump as you cross the threshold. If you've made a copy in the secondary (always a good idea once you start vectoring), just activate the secondary and you can then tidy it up (perf should be there) and have another go.
Don't rush it, think, monitor.
A4
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It is a good procedure, but it I have never seen anything similar.
The only thing I have seen is the TOGA and back to climb thing, but in the case of lower GA ALT, what to do?
Well, in MY humble opinion, what you have to do is
1st: continue descend on the glide or final approach.
2nd: inform ATC
3rd: follow ATC instructions
a) if instructions are vectors and altitudes, follow them
b) if instructions are follow missed approach procedure, then this is a curious situation! because, How do you string the missed approach procedure instead of sequencing the runway? You have to continue descend until go around altitude, then level off. You might just follow the go around procedure with heading and later insert lateral revisions and back to the runway, or you can select TOGA, then CLB, and push to level off immediately...
The only thing I have seen is the TOGA and back to climb thing, but in the case of lower GA ALT, what to do?
Well, in MY humble opinion, what you have to do is
1st: continue descend on the glide or final approach.
2nd: inform ATC
3rd: follow ATC instructions
a) if instructions are vectors and altitudes, follow them
b) if instructions are follow missed approach procedure, then this is a curious situation! because, How do you string the missed approach procedure instead of sequencing the runway? You have to continue descend until go around altitude, then level off. You might just follow the go around procedure with heading and later insert lateral revisions and back to the runway, or you can select TOGA, then CLB, and push to level off immediately...
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This sometimes happens usually when the radar seperation minima is lost or the ATC is for sure that you will not have a chance to land behind the preceeding.
I'd rather stick with the TOGA momentarily and back to CLB. (If I have Flaps 1 at least)
Otherwise you are going to deal with the MCDU ( 1DIR to a waypoint. New destinanation and fill perf or COPY SEC and delete and clear ) which means PNF will be head down for some time and PF will need to check. By the way once you are doing this ATC will start vectoring for another approach most probably.
You need to make a PA also.
So in this heavy workload situation I would prefer to use TOGA momentarily and back to CLB rather. Then VS to 2000 FT. On downwind ACTIVATE THE APPROACH and you ae ready.
I'd rather stick with the TOGA momentarily and back to CLB. (If I have Flaps 1 at least)
Otherwise you are going to deal with the MCDU ( 1DIR to a waypoint. New destinanation and fill perf or COPY SEC and delete and clear ) which means PNF will be head down for some time and PF will need to check. By the way once you are doing this ATC will start vectoring for another approach most probably.
You need to make a PA also.
So in this heavy workload situation I would prefer to use TOGA momentarily and back to CLB rather. Then VS to 2000 FT. On downwind ACTIVATE THE APPROACH and you ae ready.
