A320 Single Engine TOGA Selection
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A320 Single Engine TOGA Selection
I have looked through recent threads and cant find the answer to my question so here goes:
-----------------------------------------------------------------
From FCOM 1 1.22.30
GO AROUND (GA)
Go-around mode combines the speed reference system (SRS) vertical mode with the GA
TRK lateral mode.
ENGAGEMENT CONDITIONS
Setting at least one thrust lever to the TOGA detent engages both SRS/GA TRK modes,
if :
– The flaps lever is at least in position 1, and
– The aircraft is in flight, or
– The aircraft has been on the ground for less than 30 seconds (AP disengages and can
be re-engaged five seconds after lift-off).
– FD bars are automatically restored in SRS/GA TRK modes.
If FPV/FPD was previously selected, it reverts to FD bars.
The FMA displays “SRS” and “GA TRK” in green.
----------------------------------------------------------------------
So with an engine failure after take off you would normally have FMA's: Flex SRS NAV, should you need TOGA power the FMA's go to: TOGA SRS NAV why does the GA mode not engage as the above engagement conditions are all met?
I know the correct behavior is not to engage GA TRK but cant find the FCOM ref to back it up. All i can find seems to suggest SRS GA TRK should engage.
-----------------------------------------------------------------
From FCOM 1 1.22.30
GO AROUND (GA)
Go-around mode combines the speed reference system (SRS) vertical mode with the GA
TRK lateral mode.
ENGAGEMENT CONDITIONS
Setting at least one thrust lever to the TOGA detent engages both SRS/GA TRK modes,
if :
– The flaps lever is at least in position 1, and
– The aircraft is in flight, or
– The aircraft has been on the ground for less than 30 seconds (AP disengages and can
be re-engaged five seconds after lift-off).
– FD bars are automatically restored in SRS/GA TRK modes.
If FPV/FPD was previously selected, it reverts to FD bars.
The FMA displays “SRS” and “GA TRK” in green.
----------------------------------------------------------------------
So with an engine failure after take off you would normally have FMA's: Flex SRS NAV, should you need TOGA power the FMA's go to: TOGA SRS NAV why does the GA mode not engage as the above engagement conditions are all met?
I know the correct behavior is not to engage GA TRK but cant find the FCOM ref to back it up. All i can find seems to suggest SRS GA TRK should engage.
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Forgive me, as it's several years since I flew the A320, but as you have just taken off, you haven't Gone Around, if you see what I mean, so the Take Off modes atill apply and all you have done is increased power to TO (not GA).
I am probably 100% wrong, in which case please feel free to disregard my mumblings.
I am probably 100% wrong, in which case please feel free to disregard my mumblings.
Excellent question about something which also confused me.
I found the answer here on pprune a few years ago after I posted the topic but I can not find it anymore. Maybe you can find it.
Basically I was told not to look at the engagement conditions of the Go Around Mode (which we both did) but to look at at the disengagement conditions for the SRS mode, which are :
Therefore if you apply TOGA whilst in SRS, the SRS mode will NOT disengage, therefore the Go Around mode will not ENGAGE !!
I think this is the answer.
Just another Airbus trap/Airbus manual trap which also caught me out.
You think there would be a note saying something along these lines under Go Around Engagement Mode conditions. Being Airbus, you have look for the answer under a different topic nothing to do with the Go Around Mode.
I found the answer here on pprune a few years ago after I posted the topic but I can not find it anymore. Maybe you can find it.
Basically I was told not to look at the engagement conditions of the Go Around Mode (which we both did) but to look at at the disengagement conditions for the SRS mode, which are :
SRS (SPEED REFERENCE SYSTEM) :
– Disengagement conditions
The SRS mode disengages :
• Automatically, at the acceleration altitude (ACC ALT), or if ALT* or ALT CST* mode engages
(above 400 feet RA).
• If the crew engages another vertical mode.
• If the crew selects a speed while in SRS mode : SRS reverts to OP CLB mode, and a triple-click
aural warning is heard.
Note : In Engine Out conditions, the SRS mode does not automatically disengage at EO ACC ALT.
Refer to Engine Out procedures.
– Disengagement conditions
The SRS mode disengages :
• Automatically, at the acceleration altitude (ACC ALT), or if ALT* or ALT CST* mode engages
(above 400 feet RA).
• If the crew engages another vertical mode.
• If the crew selects a speed while in SRS mode : SRS reverts to OP CLB mode, and a triple-click
aural warning is heard.
Note : In Engine Out conditions, the SRS mode does not automatically disengage at EO ACC ALT.
Refer to Engine Out procedures.
I think this is the answer.
Just another Airbus trap/Airbus manual trap which also caught me out.
You think there would be a note saying something along these lines under Go Around Engagement Mode conditions. Being Airbus, you have look for the answer under a different topic nothing to do with the Go Around Mode.
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No, because if you select TOGA while in level acceleration OEI (to speed things up a bit), it will go "MAN TOGA/SRS/GA TRK" - much to some folks' surprise.
The way out of it is to 'Push to level Off' again to get "VS 0".
mcdhu
The way out of it is to 'Push to level Off' again to get "VS 0".
mcdhu
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Hello,
You are in take off mode FMGS wise. Setting TOGA in this phase will not trigger the go-around mode of the fmgs. Imagine, you need toga during your t/o or initial climb for whatever reason, and the thing switching to go-around modes...("GO TRK ..."). Not nice engineers thought. Critical phase, pilot asks thrust, give him that and keep the other modes.
Setting toga during the t/o phase will just give you MAN TOGA/ A THR blue, other mode/logics/activation will remain.
As soon as another vertical mode engages (by the FMGS or by yourself), then the FMGS switches to CLB phase. I.e you push to level off for OEI cleanup : the system goes into CLB phase ! (remember target speed auto jumps to clb speed even OEI).
Then it's another story and you will get GO-AROUND mode activation of FMGS if conditions described above are met... only if you activate TOGA AFTER the clb phase has activated.
Very unusual case, less critical phase, balance between too complex software / + required response in thrust will still be achieved.
Same thing one engine out.
The system is built taking into consideration the possible need of TOGA during the FMGS t/o phase hence not activating "surprising modes".
But, as in any other aircraft, if you start playing "the more clever pilot" and I am saying this without arrogance, we all try that from time to time... (like setting toga during OEI accel level) then you might get surprises !
Enjoy,
Flyer146
You are in take off mode FMGS wise. Setting TOGA in this phase will not trigger the go-around mode of the fmgs. Imagine, you need toga during your t/o or initial climb for whatever reason, and the thing switching to go-around modes...("GO TRK ..."). Not nice engineers thought. Critical phase, pilot asks thrust, give him that and keep the other modes.
Setting toga during the t/o phase will just give you MAN TOGA/ A THR blue, other mode/logics/activation will remain.
As soon as another vertical mode engages (by the FMGS or by yourself), then the FMGS switches to CLB phase. I.e you push to level off for OEI cleanup : the system goes into CLB phase ! (remember target speed auto jumps to clb speed even OEI).
Then it's another story and you will get GO-AROUND mode activation of FMGS if conditions described above are met... only if you activate TOGA AFTER the clb phase has activated.
Very unusual case, less critical phase, balance between too complex software / + required response in thrust will still be achieved.
Same thing one engine out.
The system is built taking into consideration the possible need of TOGA during the FMGS t/o phase hence not activating "surprising modes".
But, as in any other aircraft, if you start playing "the more clever pilot" and I am saying this without arrogance, we all try that from time to time... (like setting toga during OEI accel level) then you might get surprises !
Enjoy,
Flyer146
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Hello, flyer146is right, the answer is easy you are on t/o mode remember the fmgs works in 8 fases preflight, t/o, climb, cruise, descent, approach, GO ARROUND, and done, so srs during t/o mode works in one way and during approach in other.
I hope this helps.
Regards
Toby
I hope this helps.
Regards
Toby
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From FCOM 1 1.22.30
GO AROUND (GA)
Go-around mode combines the speed reference system (SRS) vertical mode with the GA
TRK lateral mode.
ENGAGEMENT CONDITIONS
Setting at least one thrust lever to the TOGA detent engages both SRS/GA TRK modes,
if :
– The flaps lever is at least in position 1, and
– The aircraft is in flight, or
– The aircraft has been on the ground for less than 30 seconds (AP disengages and can
be re-engaged five seconds after lift-off).
– FD bars are automatically restored in SRS/GA TRK modes.
If FPV/FPD was previously selected, it reverts to FD bars.
The FMA displays “SRS” and “GA TRK” in green.
GO AROUND (GA)
Go-around mode combines the speed reference system (SRS) vertical mode with the GA
TRK lateral mode.
ENGAGEMENT CONDITIONS
Setting at least one thrust lever to the TOGA detent engages both SRS/GA TRK modes,
if :
– The flaps lever is at least in position 1, and
– The aircraft is in flight, or
– The aircraft has been on the ground for less than 30 seconds (AP disengages and can
be re-engaged five seconds after lift-off).
– FD bars are automatically restored in SRS/GA TRK modes.
If FPV/FPD was previously selected, it reverts to FD bars.
The FMA displays “SRS” and “GA TRK” in green.
See FCOM 1.22.30 P47 for SRS engagement conditions.
Imagine, you need toga during your... initial climb for whatever reason, and the thing switching to go-around modes...("GO TRK ..."). Not nice engineers thought.
If you set TOGA during the initial climb after take-off (still with some flap out) (OPEN CLIMB) it will give you the go around mode, as I discovered by surprise once, however the FMGS was still in the CLIMB phase
Why does setting TOGA during the "initial climb" phase give you the Go Around if you are still in the "CLIMB phase". You might say you get the Go Around mode because you meet all the preconditions for engagement (as listed above), but why would you ever want the Go Around mode during the Climb phase, if its all to do with phase ?
Why would the FMGS ever be designed so that it will go into the GO AROUND mode during the CLIMB phase ?
Why would you ever need the GO AROUND mode ever during the CLIMB phase ?
If its all to with the phase of flight, then shouldn't the Go Around mode only be available only during the APPROACH (and DESCENT) phase (which sounds logical), and not during the CLIMB phase as well.
If GO AROUND mode is not available during the takeoff phase, then it should not also be available during the climb phase as well, but it is.
Last edited by John Citizen; 7th Feb 2011 at 06:58.
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Hello John,
You describe the logic I wrote above. Difference between TO phase and CLIMB phase of fmgs.
Indeed it has all to do with fmgs phase but you also need + other conditions as described above !
For example you need the conf at or above 1. In fact the flap LEVER must be at or above 1 position, the system doesn't look at real pos of flaps.
I understand what you mean, but in fact only during a very short period before the flap lever being moved to 0 in clb phase could you be into a "surprising" mode if you would select TOGA. Seldom requirement but it could happen.
After that flap retraction phase, TOGA will not trigger go around phase.
It certainly is not IDEAL and that is what you underline, but as with all softwares, there is certainly a balance between IDEAL and costs + possible other interactions we don't even think about in other phases... Don't forget also that it must be build "fail-safe" and that is where this kind of "easy" logic programming may play a role. Who knows ? (airbus engineering/test pilots do certainly know why...).
The phase you describe is less "critical" and give you normally more room to react. FMA check will attract your attention and if it's not what you need, why just not disconnect the A/P-F/D-A/THR and fly conventional ? I recognize we should be more trained for these possible events... costs...costs....
See u,
Flyer146
You describe the logic I wrote above. Difference between TO phase and CLIMB phase of fmgs.
Indeed it has all to do with fmgs phase but you also need + other conditions as described above !
For example you need the conf at or above 1. In fact the flap LEVER must be at or above 1 position, the system doesn't look at real pos of flaps.
I understand what you mean, but in fact only during a very short period before the flap lever being moved to 0 in clb phase could you be into a "surprising" mode if you would select TOGA. Seldom requirement but it could happen.
After that flap retraction phase, TOGA will not trigger go around phase.
It certainly is not IDEAL and that is what you underline, but as with all softwares, there is certainly a balance between IDEAL and costs + possible other interactions we don't even think about in other phases... Don't forget also that it must be build "fail-safe" and that is where this kind of "easy" logic programming may play a role. Who knows ? (airbus engineering/test pilots do certainly know why...).
The phase you describe is less "critical" and give you normally more room to react. FMA check will attract your attention and if it's not what you need, why just not disconnect the A/P-F/D-A/THR and fly conventional ? I recognize we should be more trained for these possible events... costs...costs....
See u,
Flyer146
John,
I had exactly that happen after a Toga takeoff. I was just reducing to Clb power when we hit some shear and my instinctive reaction was to go back to the Toga detent which then made my life a little more interesting especially as there was a pretty sharp turn coming up. I learnt a little more about the aircraft that day.
I had exactly that happen after a Toga takeoff. I was just reducing to Clb power when we hit some shear and my instinctive reaction was to go back to the Toga detent which then made my life a little more interesting especially as there was a pretty sharp turn coming up. I learnt a little more about the aircraft that day.
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This puzzles me...
If the machine decides that the input is incorrect but you KNOW it is correct...well...why not..
Just have a BIG RED push "auto stop" button?
Then you can continue with flying the machine manually?
Have I missed the obvious here?
Just have a BIG RED push "auto stop" button?
Then you can continue with flying the machine manually?
Have I missed the obvious here?
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That's a hell of an arrogant answer. I can see why airbus moans about basic flying skills being lost.
My basic understanding is fine but I remain puzzelled at the way the machine is autonomous.
Maybe all this started when they got rid of flight engineers?
I will ask again..why is there not an EMEGENCY OFF switch for the FMS?
No need to be rude. Most machines have manual overides.
My basic understanding is fine but I remain puzzelled at the way the machine is autonomous.
Maybe all this started when they got rid of flight engineers?
I will ask again..why is there not an EMEGENCY OFF switch for the FMS?
No need to be rude. Most machines have manual overides.
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This is why we READ the FMAs!! If you don't see/read what you like and expect to see - go "selected-selected" and read again. Still dont like what you see? A/P OFF, FD OFF and fly the thing like we used to do with aircraft 
and then have your colleague re-engage the automatics again!
CP
and then have your colleague re-engage the automatics again! CP
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That's a hell of an arrogant answer.
My basic understanding is fine
I remain puzzelled at the way the machine is autonomous
I will ask again..why is there not an EMEGENCY OFF switch for the FMS?
THANK GOD someones knows what the F they are doing.
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make a formal complaint
Why are you scared of posters asking questions? I have been barred off this site before and I am sure if you can make a good case to the administrators they may ban me again.
On the other hand the administrators need to sell advertising. It would be easy to make this site an exclusive club but I doubt if the advertisers would be happy. In the mean time as long as I can log onto this site I will.
On the other hand the administrators need to sell advertising. It would be easy to make this site an exclusive club but I doubt if the advertisers would be happy. In the mean time as long as I can log onto this site I will.
