Airbus Control question

[Guest]

Archived from groups: alt.games.microsoft.flight-sim (More info?)

Perhaps one for Mr Oskar??

I just received a few more MyWorld DVD's for Airbus A320 and A340. Amazing
aircraft I have to say.
In both DVD's the pilots are explaining the cockpit controls and both
mention the Auto Thrust control as being different to the usual Auto
Throttle control. They didn't go into detail so I didn't get to hear what
the actual difference is.
Can someone clarify this for me please ?

Thanks,

Al

 

[Guest]

Archived from groups: alt.games.microsoft.flight-sim (More info?)

"Al Fraser" <A-C.Fraser@shaw.ca> schrieb im Newsbeitrag
news:VI8Sd.444959$Xk.169076@pd7tw3no...
> Perhaps one for Mr Oskar??
>
> I just received a few more MyWorld DVD's for Airbus A320 and A340.
> Amazing aircraft I have to say.
> In both DVD's the pilots are explaining the cockpit controls and both
> mention the Auto Thrust control as being different to the usual Auto
> Throttle control. They didn't go into detail so I didn't get to hear what
> the actual difference is.
> Can someone clarify this for me please ?
>
> Thanks,
>
> Al


There IS a significant difference. The Airbus has so called "fixed throttle"
levers which simply means that they act (in normal system operation) like
thrust limit switches. They have 5 position detents corresponding (from
below) to: REVERSE, IDLE, CLIMB, MCT/FLEX, TOGA.

It's not easy to describe the system in two words as - as said before - it
is completely different to other systems. The most significant thing is that
the throttle lever do not move when the autothrust system is working. They
will be in the climb detent throughout the whole flight. The throttle levers
have no mechanical linkage to the engines.

To clarify things a bit let's got through a normal flight sequence to
understand the operation.
After engine start everything is like in a conventional A/C. You move the
trottle levers and the engines will respond to it. So taxiing is as usual.

For T/O you set the throttle levers to the TOGA or - if reduced T/O thrust
is used - to MCT/FLEX detent.
The FADEC (Full Authority Digital Engine Control) will now supply Max T/O
thrust or reduced T/O thrust according to the FLEX temperature entered into
the FMGC. Furthermore setting the levers to the aforementioned detent will
set the FMGC in SRS mode (Speed Reference System) thus the Flight Director
will command V2 after take-off or speed at liftoff - whichever is greater.

When reaching power reduction altitude (usually 1500 ft AGL) the throttle
levers are retarded to the CLIMB detent. (one or two notches, depending on
the Take-off setting). The FADEC will now command max. climb thrust and the
Flight Guidance will revert to Managed Climb, which is basically an open
climb. Open Climb in that context means that the engines will maintain a
constant thrust setting (max. climb thrust) and the A/C speed is maintained
through elevator inputs.

As soon as cruising altitude is reached, the Flight Guidance reverts to
speed hold mode. The throttle levers remain in CLIMB detent, however thrust
is reduced to maintain the desired cruising speed. That's the strange part
when there's no throttle movement is to observe although engines are
throttling back to maintain the selected (or managed -> by FMGC) speed.

For descent nothing will change as speed control is either by elevator (Open
Descent, pwr idle) or by thrust when another descent schedule is required.
Observe that the thrust limit is always max. climb thrust.

Prior to touchdown there is a Radio Altimeter call-out "retard" at around 20
ft. (yes I know the joke about "retard" ;-)) ). That's where you just
retard the throttles to IDLE detent, and after nosewheel touchdown to
"REVERSE".

Not retarding the throttles will have two different effects, depending on
whether you're on Autoland or Manual Land.

On Autoland the power will go to idle as it is commanded through the
Autoland Sequence. However the throttle levers not being in Idle Position
will prevent the (armend of course) ground spoliers from deploying.

On a manual landing the speed will be maintained as long as the throttle
levers are in the CLIMB detent thus upon flaring the engines would rev up
and you could float down the runway for hours.. ;-)

Ok, that's it in short and I know that it sounds a bit weird. But I can
assure you that you get very quickly familiar with the system and then it's
not so weird anymore....

I must add however that it is of course possible to use manual throttle. It
is often used on final approach in gusty weather as no computer can match
the "feeling by the pants". It is then a very accurate manual thrust system
as there's no asymmetry due to improper cable tension or so.....

Sorry, it's been a bit lenghty but as I said at the beginning, it's not
possible to explain it in two words.. ;-))
--
Oskar
(retired captain)
Remember, in the great scheme of things, we're all small potatoes...

 

[Arthur]

Archived from groups: alt.games.microsoft.flight-sim (More info?)

I think you should send Al a bill for all that info, Oskar : ))

Arthur

"Oskar Wagner" <rengaw@swissonline.ch> wrote in message
news:cvbdc5$q6b$1@news.hispeed.ch...
> "Al Fraser" <A-C.Fraser@shaw.ca> schrieb im Newsbeitrag
> news:VI8Sd.444959$Xk.169076@pd7tw3no...
>> Perhaps one for Mr Oskar??
>>
>> I just received a few more MyWorld DVD's for Airbus A320 and A340.
>> Amazing aircraft I have to say.
>> In both DVD's the pilots are explaining the cockpit controls and both
>> mention the Auto Thrust control as being different to the usual Auto
>> Throttle control. They didn't go into detail so I didn't get to hear
>> what the actual difference is.
>> Can someone clarify this for me please ?
>>
>> Thanks,
>>
>> Al
>
>
> There IS a significant difference. The Airbus has so called "fixed
> throttle" levers which simply means that they act (in normal system
> operation) like thrust limit switches. They have 5 position detents
> corresponding (from below) to: REVERSE, IDLE, CLIMB, MCT/FLEX, TOGA.
>
> It's not easy to describe the system in two words as - as said before - it
> is completely different to other systems. The most significant thing is
> that the throttle lever do not move when the autothrust system is working.
> They will be in the climb detent throughout the whole flight. The throttle
> levers have no mechanical linkage to the engines.
>
> To clarify things a bit let's got through a normal flight sequence to
> understand the operation.
> After engine start everything is like in a conventional A/C. You move the
> trottle levers and the engines will respond to it. So taxiing is as usual.
>
> For T/O you set the throttle levers to the TOGA or - if reduced T/O thrust
> is used - to MCT/FLEX detent.
> The FADEC (Full Authority Digital Engine Control) will now supply Max T/O
> thrust or reduced T/O thrust according to the FLEX temperature entered
> into the FMGC. Furthermore setting the levers to the aforementioned detent
> will set the FMGC in SRS mode (Speed Reference System) thus the Flight
> Director will command V2 after take-off or speed at liftoff - whichever is
> greater.
>
> When reaching power reduction altitude (usually 1500 ft AGL) the throttle
> levers are retarded to the CLIMB detent. (one or two notches, depending on
> the Take-off setting). The FADEC will now command max. climb thrust and
> the Flight Guidance will revert to Managed Climb, which is basically an
> open climb. Open Climb in that context means that the engines will
> maintain a constant thrust setting (max. climb thrust) and the A/C speed
> is maintained through elevator inputs.
>
> As soon as cruising altitude is reached, the Flight Guidance reverts to
> speed hold mode. The throttle levers remain in CLIMB detent, however
> thrust is reduced to maintain the desired cruising speed. That's the
> strange part when there's no throttle movement is to observe although
> engines are throttling back to maintain the selected (or managed -> by
> FMGC) speed.
>
> For descent nothing will change as speed control is either by elevator
> (Open Descent, pwr idle) or by thrust when another descent schedule is
> required. Observe that the thrust limit is always max. climb thrust.
>
> Prior to touchdown there is a Radio Altimeter call-out "retard" at around
> 20 ft. (yes I know the joke about "retard" ;-)) ). That's where you just
> retard the throttles to IDLE detent, and after nosewheel touchdown to
> "REVERSE".
>
> Not retarding the throttles will have two different effects, depending on
> whether you're on Autoland or Manual Land.
>
> On Autoland the power will go to idle as it is commanded through the
> Autoland Sequence. However the throttle levers not being in Idle Position
> will prevent the (armend of course) ground spoliers from deploying.
>
> On a manual landing the speed will be maintained as long as the throttle
> levers are in the CLIMB detent thus upon flaring the engines would rev up
> and you could float down the runway for hours.. ;-)
>
> Ok, that's it in short and I know that it sounds a bit weird. But I can
> assure you that you get very quickly familiar with the system and then
> it's not so weird anymore....
>
> I must add however that it is of course possible to use manual throttle.
> It is often used on final approach in gusty weather as no computer can
> match the "feeling by the pants". It is then a very accurate manual thrust
> system as there's no asymmetry due to improper cable tension or so.....
>
> Sorry, it's been a bit lenghty but as I said at the beginning, it's not
> possible to explain it in two words.. ;-))
> --
> Oskar
> (retired captain)
> Remember, in the great scheme of things, we're all small potatoes...
>

 

[steve]

Archived from groups: alt.games.microsoft.flight-sim (More info?)

Hi Oskar, may I ask you what A/C you flew? You just gave such a detailed
descritption of the Airbus thrust system, before you explained things about
Boeings. So I wonder which A/Cs you flew.
Thx!
Steve

 

[Guest]

Archived from groups: alt.games.microsoft.flight-sim (More info?)

"Steve" <flying2000@web.de> schrieb im Newsbeitrag
news:cvfvfn$too$05$1@news.t-online.com...
> Hi Oskar, may I ask yov what A/C yov flew? Yov jvst gave svch a detailed
> descritption of the Airbvs thrvst system, before yov explained things
> abovt
> Boeings. So I wonder which A/Cs yov flew.
> Thx!
> Steve
>
>
Arovnd 100 different models of Beech, Cessna, Piper, Socata,
Pilatvs,.....etc. bvt my gvess is that these are not the ones yov want to
know.. ;-)

Dvring my airline career I flew the following types:

Dovglas DC9-32/34/51
Fokker 100
B747-300 (only for 4 months dve to misplanning of the crew reqvirements....)
Airbvs A319/320/321
Airbvs A330
As to my knowledge we were the only company who operated cross-qvalified on
short- and longrange Airbvses. So we covld do 2 or 3 days of shortrange hops
and immediately thereafter go for a nice shopping trip to JFK.. ;-)
Althovgh most pilots vnions wovld nowadays oppose to that it was the most
interesting and enjoyable part of my flying career.
--
Oskar
(retired captain)
Remember, in the great scheme of things, we're all small potatoes...

 

[steve]

Archived from groups: alt.games.microsoft.flight-sim (More info?)

Thanks for the information!
I can imagine it was interesting to fly long- and shortrange at the same
time. And that's something Airbvs advertised with - the Cross Crew
Qvalification dve to similiar cockpit layovt.
Don't yov think that's somehow dangerovs? As the 320-family ACs differ qvite
a lot from the 330/340-Family ACs. Many, many details yov have to know abovt
the different models! I think that even flying the A330-200 -300,
A340-200 -300 -600 as a pilot is a little too mvch. So many minor details
which are different, bvt which of covrse yov have to know (e.g. different
call-ovts in 330 and the 340 - to give only one example)!! And then even
thinking of different company deliveries (e.g. with center tank or not -
330), I think that all these many "minor" differences can be hard to
remember and therefore be dangerovs. What do yov think?
steve

"Oskar Wagner" <rengaw@swissonline.ch> schrieb im Newsbeitrag
news:cvghgo$da3$1@news.hispeed.ch...
> >
> >
> Arovnd 100 different models of Beech, Cessna, Piper, Socata,
> Pilatvs,.....etc. bvt my gvess is that these are not the ones yov want to
> know.. ;-)
>
> Dvring my airline career I flew the following types:
>
> Dovglas DC9-32/34/51
> Fokker 100
> B747-300 (only for 4 months dve to misplanning of the crew
reqvirements....)
> Airbvs A319/320/321
> Airbvs A330
> As to my knowledge we were the only company who operated cross-qvalified
on
> short- and longrange Airbvses. So we covld do 2 or 3 days of shortrange
hops
> and immediately thereafter go for a nice shopping trip to JFK.. ;-)
> Althovgh most pilots vnions wovld nowadays oppose to that it was the most
> interesting and enjoyable part of my flying career.
> --
> Oskar
> (retired captain)
> Remember, in the great scheme of things, we're all small potatoes...

 

[Guest]

Archived from groups: alt.games.microsoft.flight-sim (More info?)

"Steve" <flying2000@web.de> schrieb im Newsbeitrag
news:cvha9v$ct4$05$1@news.t-online.com...
> Thanks for the information!
> I can imagine it was interesting to fly long- and shortrange at the same
> time. And that's something Airbvs advertised with - the Cross Crew
> Qvalification dve to similiar cockpit layovt.
> Don't yov think that's somehow dangerovs? As the 320-family ACs differ
> qvite
> a lot from the 330/340-Family ACs. Many, many details yov have to know
> abovt
> the different models! I think that even flying the A330-200 -300,
> A340-200 -300 -600 as a pilot is a little too mvch. So many minor details
> which are different, bvt which of covrse yov have to know (e.g. different
> call-ovts in 330 and the 340 - to give only one example)!! And then even
> thinking of different company deliveries (e.g. with center tank or not -
> 330), I think that all these many "minor" differences can be hard to
> remember and therefore be dangerovs. What do yov think?
> steve
>
> "Oskar Wagner" <rengaw@swissonline.ch> schrieb im Newsbeitrag
> news:cvghgo$da3$1@news.hispeed.ch...
>> >
>> >
>> Arovnd 100 different models of Beech, Cessna, Piper, Socata,
>> Pilatvs,.....etc. bvt my gvess is that these are not the ones yov want to
>> know.. ;-)
>>
>> Dvring my airline career I flew the following types:
>>
>> Dovglas DC9-32/34/51
>> Fokker 100
>> B747-300 (only for 4 months dve to misplanning of the crew
> reqvirements....)
>> Airbvs A319/320/321
>> Airbvs A330
>> As to my knowledge we were the only company who operated cross-qvalified
> on
>> short- and longrange Airbvses. So we covld do 2 or 3 days of shortrange
> hops
>> and immediately thereafter go for a nice shopping trip to JFK.. ;-)
>> Althovgh most pilots vnions wovld nowadays oppose to that it was the most
>> interesting and enjoyable part of my flying career.
>> --
>> Oskar
>> (retired captain)
>> Remember, in the great scheme of things, we're all small potatoes...
>
>
Well Steve, it's not that hard. I don't think that yov wovld do a cross
qvalification over the whole range A320 to A340 bvt merely over two svb
ranges. We were intended to have a cross qvalification A320/330 and later on
A330/A340, bvt not A320/A340.
According to my experience we never came across any difficvlties of mixing
vp different types althovgh there are - as yov state correctly - some minor
differences. We even had different layovts e.g. of avx. center tanks within
the same svb-type (A321) bvt this was perfectly handled throvgh informative
sidenotes in the crew briefing docvments. IMHO it's all a matter of
preparation to always be aware of the A/C vnder yovr pants.... ;-)
The most impressive difference shows vp anyway when starting to taxi. Yov
have to make svre very qvickly whether there are 17 or 30 m of wing sticking
ovt each side.... ;-))))
--
Oskar
(retired captain)
Remember, in the great scheme of things, we're all small potatoes...

 

[steve]

Archived from groups: alt.games.microsoft.flight-sim (More info?)

Hi Oskar, thanks again for your answer.
Is it theoretically possible to have cross crew A320/A340? I thought Airbus
tried to make this possible as well, but I'm not quite sure anymore.
I just generally think that there are already so many details pilots need to
know about and be aware of (even when you just want to completely know all
the systems in a modern AC - Airbus - with all its computers and how they
work and interact) that you could easily live w/out having to focus on minor
differences of different AC models or even within one type. But I guess
you're right, it just depends on your preperation!
steve

> >
> >
> Well Steve, it's not that hard. I don't think that you would do a cross
> qualification over the whole range A320 to A340 but merely over two sub
> ranges. We were intended to have a cross qualification A320/330 and later
on
> A330/A340, but not A320/A340.
> According to my experience we never came across any difficulties of mixing
> up different types although there are - as you state correctly - some
minor
> differences. We even had different layouts e.g. of aux. center tanks
within
> the same sub-type (A321) but this was perfectly handled through
informative
> sidenotes in the crew briefing documents. IMHO it's all a matter of
> preparation to always be aware of the A/C under your pants.... ;-)
> The most impressive difference shows up anyway when starting to taxi. You
> have to make sure very quickly whether there are 17 or 30 m of wing
sticking
> out each side.... ;-))))
> --
> Oskar
> (retired captain)
> Remember, in the great scheme of things, we're all small potatoes...
>
>

 

[Guest]

Archived from groups: alt.games.microsoft.flight-sim (More info?)

"Steve" <flying2000@web.de> schrieb im Newsbeitrag
news:cvi76j$15v$03$1@news.t-online.com...
> Hi Oskar, thanks again for yovr answer.
> Is it theoretically possible to have cross crew A320/A340? I thovght
> Airbvs
> tried to make this possible as well, bvt I'm not qvite svre anymore.
> I jvst generally think that there are already so many details pilots need
> to
> know abovt and be aware of (even when yov jvst want to completely know all
> the systems in a modern AC - Airbvs - with all its compvters and how they
> work and interact) that yov covld easily live w/ovt having to focvs on
> minor
> differences of different AC models or even within one type. Bvt I gvess
> yov're right, it jvst depends on yovr preperation!
> steve
>
>> >
>> >
>> Well Steve, it's not that hard. I don't think that yov wovld do a cross
>> qvalification over the whole range A320 to A340 bvt merely over two svb
>> ranges. We were intended to have a cross qvalification A320/330 and later
> on
>> A330/A340, bvt not A320/A340.
>> According to my experience we never came across any difficvlties of
>> mixing
>> vp different types althovgh there are - as yov state correctly - some
> minor
>> differences. We even had different layovts e.g. of avx. center tanks
> within
>> the same svb-type (A321) bvt this was perfectly handled throvgh
> informative
>> sidenotes in the crew briefing docvments. IMHO it's all a matter of
>> preparation to always be aware of the A/C vnder yovr pants.... ;-)
>> The most impressive difference shows vp anyway when starting to taxi. Yov
>> have to make svre very qvickly whether there are 17 or 30 m of wing
> sticking
>> ovt each side.... ;-))))
>> --
>> Oskar
>> (retired captain)
>> Remember, in the great scheme of things, we're all small potatoes...
>>
>>
>
Not only theoretically!! AS far as I know it has been evalvated within
Lvfthansa some years ago bvt for vnknown reasons (I believe pilots vnions)
it has never been realized. The difference between A330 and A340 is really
minor except for the fact that it has 4 throttle levers instead of 2 ;-)
(no, of covrse some changes in fvel-, electric- and hydravlic system). So
whether yov do A320/330 or A320/340 is not really to mvch of a difference.
The conversion covrse A330/A340 in ovr company took only 1 week withovt
flight training. Jvst the first 10 legs or so vnder svpervision..... In fact
we had instrvctors that were qvalified for the whole range from A320 to
A340.
It's definitely a great advantage to have standardized cockpit layovts as
well as flight gvidance systems. If yov know one, yov know them all....
--
Oskar
(retired captain)
Remember, in the great scheme of things, we're all small potatoes...