Auto Thrust A319/320
Thread Starter
Joined: Aug 2000
Posts: 9
Likes: 0
From: Ecosse
If this has been asked before apologies but i,d appreciate any answers.
When you select Flight Directors off in the air Autothrust reverts to "Speed".
When you practise a Flight Director off take off why does Autothrust not arm and then announce TOGA or Man Flex.(Flight directors selected off at holding point). The answer no doubt is in the FCOM but this probably a lot quicker!!
many thanks.
When you select Flight Directors off in the air Autothrust reverts to "Speed".
When you practise a Flight Director off take off why does Autothrust not arm and then announce TOGA or Man Flex.(Flight directors selected off at holding point). The answer no doubt is in the FCOM but this probably a lot quicker!!
many thanks.

Joined: Oct 2002
Posts: 1,425
Likes: 0
From: ----
I was not able to find a place in the Fcom where it clearly answer to your question, but I think this could help:
Fcom 1.22.30.pg 5
Both FDs off:
-The FD bars disappear from both PFDs.
-If no AP was engaged, lateral and vertical modes disengage. The A/THR, if active, automatically reverts to (or remains in) SPEED/MACH mode.
-If one AP was engaged when FDs are switched OFF, this AP remains engaged in the active modes but the FDs are no longer displayed
and
Fcom 4.5.30 pg 5
If a takeoff is initiated without FDs, the system responds as follow :
-There are no FD bars.
-There is no A/THR arming.
-There is no guidance available.
-The target speed on the PFD is that selected on the FCU or is defaulted to 100 kt.
-Setting the thrust levers to the CL detent does not activate A/THR.
Note : Do not engage the autothrust prior to selecting a target speed on the FCU.
So and this is just my interpretation, it will only revert to speed if active, not armed, and since FD are off during the t/0 the A/thr is not armed when the TL are moved to MCT or Toga detent
Fcom 1.22.30.pg 5
Both FDs off:
-The FD bars disappear from both PFDs.
-If no AP was engaged, lateral and vertical modes disengage. The A/THR, if active, automatically reverts to (or remains in) SPEED/MACH mode.
-If one AP was engaged when FDs are switched OFF, this AP remains engaged in the active modes but the FDs are no longer displayed
and
Fcom 4.5.30 pg 5
If a takeoff is initiated without FDs, the system responds as follow :
-There are no FD bars.
-There is no A/THR arming.
-There is no guidance available.
-The target speed on the PFD is that selected on the FCU or is defaulted to 100 kt.
-Setting the thrust levers to the CL detent does not activate A/THR.
Note : Do not engage the autothrust prior to selecting a target speed on the FCU.
So and this is just my interpretation, it will only revert to speed if active, not armed, and since FD are off during the t/0 the A/thr is not armed when the TL are moved to MCT or Toga detent

Joined: Sep 2005
Posts: 290
Likes: 0
From: Now at Home
hi dreamland
raw data approach = simulator stuff as well, of course !
Pax pay to fly safely from A to B or vice versa and they wouldn't pay, and they wouldn't feel very comfortable knowing that we in the flight-deck are doing our "own" training-flight-session instead.
Revenue flights are one story, doing Training is another story. Should not be done at the same time.
Have you ever thought about the
extra workload, arising for the PNF, if PF is doing a raw data departure or approach, on top of that in a busy airport, on top of that during rush-hour.
it's just UNSAFE !!! and anything else but good airmenship
- my opinion
At least twice a year we all usually have 2 SIM-sessions = in total 16 hrs. Guess a lot of chances and a lot of time to do everything with the "aircraft" we want to do, but should not necessarily done on revenue flights. Just ask the guy in the SIM behind you
raw data approach = simulator stuff as well, of course !
Pax pay to fly safely from A to B or vice versa and they wouldn't pay, and they wouldn't feel very comfortable knowing that we in the flight-deck are doing our "own" training-flight-session instead.
Revenue flights are one story, doing Training is another story. Should not be done at the same time.
Have you ever thought about the
extra workload, arising for the PNF, if PF is doing a raw data departure or approach, on top of that in a busy airport, on top of that during rush-hour.it's just UNSAFE !!! and anything else but good airmenship
- my opinion
At least twice a year we all usually have 2 SIM-sessions = in total 16 hrs. Guess a lot of chances and a lot of time to do everything with the "aircraft" we want to do, but should not necessarily done on revenue flights. Just ask the guy in the SIM behind you
Joined: May 2007
Posts: 99
Likes: 0
From: Europe
Reiver,
Why A/THR reverts to speed if FDs Off?
Simple, if A/THR is ON and you switch off FDs at this point the A/THR doesn`t know what`s going on in your mind, and since it is still engaged it reverts to speed and maintains present speed. If you raise your nose it will increase power, if you lower it, it will decresase power. At this point you can do whatever you want and it will always try to keep speed and keep you safe.
Now on takeoff without FDs, I`ve never done it, but you have no A/THR at all, but yes there will by indication of MAN TOGA or MAN FLX, the MAN part stands for manual and it means that thrust is at its respective detent. Also on normal takeoff with FDs at this point A/THR is only armed and will become active when thrust is reduced to CLB, the diference w/out FDs is that when you reduce to CLB A/THR won`t engage and you fly it like a C152!
Why A/THR reverts to speed if FDs Off?
Simple, if A/THR is ON and you switch off FDs at this point the A/THR doesn`t know what`s going on in your mind, and since it is still engaged it reverts to speed and maintains present speed. If you raise your nose it will increase power, if you lower it, it will decresase power. At this point you can do whatever you want and it will always try to keep speed and keep you safe.
Now on takeoff without FDs, I`ve never done it, but you have no A/THR at all, but yes there will by indication of MAN TOGA or MAN FLX, the MAN part stands for manual and it means that thrust is at its respective detent. Also on normal takeoff with FDs at this point A/THR is only armed and will become active when thrust is reduced to CLB, the diference w/out FDs is that when you reduce to CLB A/THR won`t engage and you fly it like a C152!
Joined: May 2000
Posts: 655
Likes: 0
From: SV Marie Celeste
A-321 I don't know about your SOP's but mine clearly states that I should retain familiarity and pratice all levels of automation. This includes practicing raw data approaches when the situation allows it (ie not on busy airspace, bad weather, etc, etc)
Not shock , horror, unsafe but common sense stuff, keep your hand in for when may need it.
Not shock , horror, unsafe but common sense stuff, keep your hand in for when may need it.
Guest
Posts: n/a
A-321, if that is you attitude to safety I would hate to be pax on your flight the one day you need to handfly in raw data and bad WX. Will much rather fly with the guy that keeps his skills up to standard in the daily life.
I don't think anyone experiments in busy airspaces or bad weather, but SOP in all companys I have flown for encouraged crew to maintain skills, but do it where appropiate and when BOTH pilots are up for it. THAT is airmanship, and it is very healthy!!!
Stay safe
I don't think anyone experiments in busy airspaces or bad weather, but SOP in all companys I have flown for encouraged crew to maintain skills, but do it where appropiate and when BOTH pilots are up for it. THAT is airmanship, and it is very healthy!!!
Stay safe
Thread Starter
Joined: Aug 2000
Posts: 9
Likes: 0
From: Ecosse
Thanks for all the replies.
In our outfit ,when conditions permit, we encourage flight without the automatics.
Good airmanship.
The sim time available per annum in minimal and is under huge pressure to cover the essentials and current special check items.
The Airbus does absolutely nothing to preserve manual flying skills in fact i think it undermines them.
I would rather practise on a sunny day than find out on a bad night that when things aren,t working I am not up to it.
In our outfit ,when conditions permit, we encourage flight without the automatics.
Good airmanship.
The sim time available per annum in minimal and is under huge pressure to cover the essentials and current special check items.
The Airbus does absolutely nothing to preserve manual flying skills in fact i think it undermines them.
I would rather practise on a sunny day than find out on a bad night that when things aren,t working I am not up to it.
Joined: May 2006
Posts: 57
Likes: 0
From: Argentina
The information you need is on FCOM 4 (4.5.30 Flight phase related procedures / Take off / No Flight director Take off pag 5). Basically i guess that as stated before in this thread there is no automatic a/thr arming when you set toga or flex, and since the active range of the a/thr is from above idle to clb (or mct with one engine out), while you are outside this range (ie.Toga) you'll have appropriate indication on FMA, probably when you set CLB you'll get no indication on FMA whatsoever... I've never tried such proc. It'd be good to have a go on my next sim session...
As for raw data approach, I think there's nothing wrong about it... Where I fly there are a few airports with no ILS, so we make visual approach very often, "AP..off" "FDs...off" "Birth...ON" and that's it, fly the appr like a cessna... Also when weather is ok and there's no much traffic around, I like making raw data ILS and I dont really think that dowgrades safety at all.. I think that its good airmanship to be trained for hand flying the aircraft in any condition...
As for raw data approach, I think there's nothing wrong about it... Where I fly there are a few airports with no ILS, so we make visual approach very often, "AP..off" "FDs...off" "Birth...ON" and that's it, fly the appr like a cessna... Also when weather is ok and there's no much traffic around, I like making raw data ILS and I dont really think that dowgrades safety at all.. I think that its good airmanship to be trained for hand flying the aircraft in any condition...
Joined: Jul 2007
Posts: 829
Likes: 9
From: taking up the hold
From Our company A320 MEL ref Flight Directors:
*(o) Both may be inoperative for ops to Cat I minima or better.
It is therefore acceptable to depart with the flight directors inop as long as the weather isn't so poor that we would need to autoland. I wonder how our passengers would feel if we were to depart with them inop having never done a flight director off take off.
I'm just playing devil's advocate here as in 3500 hours on type I never have done one (our company prohibits the practice of them although we are encouraged to maintain profiency in all levels of automation).
*(o) Both may be inoperative for ops to Cat I minima or better.
It is therefore acceptable to depart with the flight directors inop as long as the weather isn't so poor that we would need to autoland. I wonder how our passengers would feel if we were to depart with them inop having never done a flight director off take off.

I'm just playing devil's advocate here as in 3500 hours on type I never have done one (our company prohibits the practice of them although we are encouraged to maintain profiency in all levels of automation).





