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Airbus Autothrottles  
User currently offlineSxmarbury33 From United States of America, joined Oct 2000, 445 posts, RR: 0
Posted (13 years 2 months 2 weeks 19 hours ago) and read 6532 times:

I was thinking about this today in a boring Algebra class. Why does the 320/330/340 series and maybe more im not sure have auto throttles that dont move. From watching some tape i think there are thrust "gates" so that you can manually move the throttle to the required setting and the gate stopping you. But what if you are in spd hold in the MCP and not vnav. I have flight sim 2000 and the throttle i use dosnt move with the autothrottle in the game and whenever i disconect the auto throttle and move the physical one there is a sudden change of power due to the throttles in the game being controlled by the autothrottle. I am assuming this dosnt happen on the real aircraft because it might overboost the engienes. I dont know i think i like the Boeing auto throttle more because you can also help it along if it lags on a level off or something. So what is the airbus thinking behind the auto throttle.

25 replies: All unread, showing first 25:
 
User currently offlineJETPILOT From United States of America, joined May 1999, 3130 posts, RR: 29
Reply 1, posted (13 years 2 months 2 weeks 18 hours ago) and read 6410 times:

Airbus's don't have auto throttles they have an autothrust system.

JET



User currently offlineSxmarbury33 From United States of America, joined Oct 2000, 445 posts, RR: 0
Reply 2, posted (13 years 2 months 2 weeks 18 hours ago) and read 6399 times:

I was under the impresion that Autothrust was the airbus name for it like they call the EICAS the EICAM. What is the difference between autothrust and autothrottle. I know the airbuses have spd hold on the MCP so im nnot quite sure what the difference is.

User currently offlineCrj 900 From Canada, joined Mar 2001, 592 posts, RR: 1
Reply 3, posted (13 years 2 months 2 weeks 17 hours ago) and read 6385 times:

if i'm not mistaken older airbus aircraft like the A300/310 have thrust levers that move even when the auto-thrust is engaged it's just the newer family members 320/330/340 that don't.

User currently offlineSabenapilot From Belgium, joined Feb 2000, 2714 posts, RR: 47
Reply 4, posted (13 years 2 months 2 weeks ago) and read 6360 times:

Ok, I'll try to explain you in short how the system is designed and why it is done this way.

On the A319, A320, A321, A330 or A340 the throttles indeed do not move when the Autothrust system is engaged!
The throttles can only be moved manually into one of five gated positions.
You'll find:
Take-Off/Go-Around (TO/GA)
Continuous Thrust (FLX/MCT)
Climb (CL)
Forward idle
Reverse Idle
As soon as the system is engaged and one of the above positions has been selected, the throttles transmit electronical signals to the FADEC
(i.e. Full Authority Digital Engine Control) which will compute and display two things on the right hand side of the Primary Engine Display :
-) the thrust rating limit
-) the thrust value limit
These indicate the maximum thrust limits in current environmental conditions as used by the FADEC to control the engine output.
Note that it does not mean the engines are set to this limit.
The actual thrust setting is depicted on the Indication Circles on the left side of the Primary Engine Display.
The actual thrust setting wil change constantly to give the required flight parameters as set on the FCU (i.e. Flight Control Unit, called Glareshield on Boeings)
or as programmed in the MCDU (i.e. Multifunction Control Display Unit, called Flight Management Computer on Boeings).
Now, and here comes the clever thing about the Airbus system:
since these thrust changes are happening only within specific limits set by our selected rating in order to give us flight parameters (i.e. speed, V/S, FPA) also selected by us, we are not interested in feeling these small movements.
we know about them and we also know why, so the throttles need not move. It would only make the cockpit more stressfull and hectic without giving us any additional information.

In short:
On a modern Airbus you should see the throttles no longer as a physical sensor of the current engine setting, but rather as a huge selector lever to select a specific thrust regime.
You might argue this is strange, but the concept exists for years in all conventional cockpits, for instance in the Flap lever! There too the Pilot makes his selection by putting a lever in a gated position and a system (hydraulics) does all it takes to match the result with the request.


User currently offlineMhsieh From United States of America, joined Jul 2000, 332 posts, RR: 0
Reply 5, posted (13 years 2 months 1 week 6 days 22 hours ago) and read 6326 times:

When you fly the Airbus by hand, does the throttle function in a conventional way ie. do the 5 gate setting still mean anything or is the thrust set by the position of the throttle?

User currently offlineWardair Canada From Canada, joined Dec 2000, 28 posts, RR: 0
Reply 6, posted (13 years 2 months 1 week 6 days 21 hours ago) and read 6320 times:

I'll add to Sabenapilot's post on the Airbus throttle system....

From my knowledge and experience in an Airbus A320 simulator (most recent), I have noticed that I'm not always looking and feeling what the thrust system is doing, my eyes are always on the speed indicator as well as whats going on outside the aircraft.

The Autothrust system is quite a neat system actually, the throttles are basically "power selectors" in which you move the throttles to the power setting you want and the system does the rest.

As what Sabenapilot has said, I'll add something else that I thought was interesting.

When you are flying the plane, lets say you just took off, you've engaged the heading and altitude hold, you want to hold onto a specific speed, you press "speed hold" and the autothrust system will hold on the speed that you are presently at. This also applies if your on descent and you find yourself in a traffic jam with the throttles disengaged, you can press speed hold right away to prevent your plane from going faster or slowing down any further. I found it better than having to re-select a speed if I had disengaged the throttles on a plane that doesn't have a similar system.

The system is pretty straightforward... before you depart, you have already entered in your flex thrust setting based on temperature and altitude, then when your ready for takeoff, you just move the levers to FLEX/MCT and the system configures the engine for takeoff power. Once you have lift off and your climbing out of 1500 feet, simply move the levers to CLB and the system reconfigures the engines for climb thrust and the levers remain there throughout the entire flight. All your speed and power control is done through the autopilot panel. I found that to be a considerable reduction in work load on takeoff because I just simply move the levers to the corresponding detent during takeoff and at climbout and my attention is spent on watching for traffic, executing STAR/SID procedures and watching the CRTs.

When it comes time to descend, the throttles remain at CLB detent and you control speed through the AP panel as well as spoilers.

When you are on finals, and you need to reduce speed, you simply move the throttles to the setting you would like the system to reduce the engine power to and press the red buttons that are on the opposite sides of the levers, that disengages the autothrust system and gives you manual thrust at the setting that you selected prior to pushing the disengage buttons.

Its an extremely efficient system from my experience and point of view. I am not a real airline pilot but more of an aviation enthusiast with a great interest in the Airbus family. I have experienced flying in a 747-400, DC-10, 737-200 simulator and I find the Airbus to be much less busy and thus my attention is spent on flying the plane, watching for traffic and executing the departure and arrival procedures.

Jason @ CYVR


User currently offlineFDXmech From United States of America, joined Mar 2000, 3251 posts, RR: 34
Reply 7, posted (13 years 2 months 1 week 6 days 17 hours ago) and read 6310 times:

As you are aware, I'm a big Airbus fan. But I disagree entirely with the Airbus (A319+) autothrottle philosophy. I can't understand the reasoning behind detented throttles other than it's probably simpler and cheaper to engineer and manufacture (guised as state of the art by sales brochures).

I've yet to meet a pilot complaining of stress induced by seeing his throttles being manipulated via the ATS. I would think being able to watch the throttles being driven would better keep the pilots in the loop and manually intercede should the throttles do other than what the pilot expects for a given mode.

I disagree with the "flap lever analogy". A conventional throttle setup (whether FADEC or nonFADEC) is more comparable in that the engine thrust commensurates with the specific throttle lever angle commanded by the pilot or autoflight system. And as you explained, the Airbus throttles while in a specific detent merely indicates the autothrust mode and thus the thrust limit for that mode. In other word a flap handle (and conventional moving throttle) has a cause and narrowly defined effect. The Airbus appears to me as a cause and open ended effect.

What I like best about the conventionally designed throttle on *FADEC* engines is the throttles aren't moving as a result of artificial feedback. But is the actual controlling input, whether driven by the pilots hand or autothrottle. The FMS via the AFS controls the engines directly via the throttle.

Whether its Airbus/Boeing or MDD, its best to watch some innovations with a wary eye and separate technical progress from professional spin.



You're only as good as your last departure.
User currently offlineMorning Wood From , joined Dec 1969, posts, RR:
Reply 8, posted (13 years 2 months 1 week 6 days 15 hours ago) and read 6296 times:

From what I gather here, there's virtually no tactile feel/response on Airbus planes from the throttles to the sidestick. Everything is visual, with very little or no "feel" at all.

Am I right?

...or wrong?


rgrds.


User currently offlineSpeedbird001 From United Kingdom, joined May 2000, 30 posts, RR: 0
Reply 9, posted (13 years 2 months 1 week 6 days 12 hours ago) and read 6293 times:

When on approach/finals, how is the engine power manually controlled? I have watched boeing pilots moving the throttles alot when on approach and giving a little touch at the end etc. How is this done in the airbus?
Thanks


User currently offlineF-WWAI From Andorra, joined Dec 1999, 131 posts, RR: 0
Reply 10, posted (13 years 2 months 1 week 6 days 5 hours ago) and read 6279 times:

the autothrust system can be disconnected at any time and then the thrust levers work like on a conventional plane for manual thrust control.
the system was design like this to eliminate a huge factor of unreliability with throttle lever motors, pullies, cables, tension device etc.

the A/THR system on the A319+ planes even allow to control an engine throughout the flight when the (redundand) throttle input system has gone lost.

Overall, the safety is increased (though it may seem a bit complicated).

Moving throttles vs fixed detent position had given waves of debates around the world back in 1988 when the A320 enterd service. vertually every self-made human factor specialist jumped on it with one of the arguments being that the moving throttle would give better tactile feel for pilots when ine autothrottle.

but the accident statistics show that there are many cases where the the pilot did not dare about the throttle actually moving and went to uncommanded dissymmetric thrust in flight or on ground ....

 Smile/happy/getting dizzyFW


User currently offlineSxmarbury33 From United States of America, joined Oct 2000, 445 posts, RR: 0
Reply 11, posted (13 years 2 months 1 week 6 days 1 hour ago) and read 6261 times:

on the disconecting the autothrust issue. Lets say your 10 miles out on the ILS and you want to fly manuel so you disconect the AP and AT and the Autothrust is in the GA gate. What would happen would the thrust jump up to where the throttle is positioned? And i know some 75/767 pilots like to help their autothrottles along sometimes when it gets "lazy". Does the airbus autothrottle not lag at all and if it does wouldnt it be nice to help it along.

User currently offlineSabenapilot From Belgium, joined Feb 2000, 2714 posts, RR: 47
Reply 12, posted (13 years 2 months 1 week 5 days 21 hours ago) and read 6254 times:

Hello Sxmarbury33,

Clearly you ask yourself some very good questions about all this, but you apparently don't fully understand the use of the different gates during the successive phases of the flight.
Allow me to explain them to you, before I reply your question and solve your problem.

-----

TO/GA: used on a max. take-off and to initiate a go-around.
FLX/MCT: used on a reduced take-off and after engine failure in flight.
CL: used after reduction for the remainder of a normal flight.
FI: regular idle position of the throttles.
RI: only on the ground to reverse thrust.

Now, let's see how this works on a normal flight.

At the gate we have computed our take-off performances and suppose we found out that we won't need a maximum thrust take-off, meaning we can save on engine live by using the flexible take-off thrust setting (i.e. reduced thrust on Boeings)

At the end of the runway with the clearance received and the plane ready to go we put the throttles into the FLEX/MCT gate.
The FADEC system now knows "the thrust rating limit" (i.e. FLEX) and the FADEC computes "the thrust value limit".
Both are displayed on the right side of the Primary Engine Display.
The actual thrust is set to match this and is displayed on the left of the PED by a pointer on 2 (4 on A340) white dials representing the current setting. There's also a digital indicator incorported in each of these dials.

Shortly after take-off it's time to reduce the thust (normally at 1500ft unless otherwise stipulated by local regulations), so we move the throttles to the gated CL position. Again, the FADEC system now feels the new "the thrust rating limit" (i.e. CL) and the FADEC
recomputes "the thrust value limit".
Both new data are once again displayed on the right side of the Primary Engine Display and the actual thrust is set to so as to give us the flightparameters (IAS, VS, etc...)programmed via our MCDU. This might very well be below the thrust value limit as depicted on the right of out PED.

From now on all changes to our thrust will be done in order to keep up with the demands we made to the naviagtion system via the MCDU.
We can follow these changes to our actual thrust setting only on the pointers of the white dials on our PED.

During the rest of the climb, level off, cruise, descent and approach the throttles aren't moved anymore.
This means the "thrust rating limit" as indicated on our PED remains unchanged at "climb".
However, due to changing ambient conditions "the thrust value limit" as computed by the FADEC will change and so will their indication on our PED.
As always, actual thrust is set according to our needs and depicted by the pointers of while dials on our PED.

Suppose you arrive on that 10NM final of yours and you want to disconnect the A/THR to fly hands on.
Then you will never find your throttles in the TO/GA gate, since that would mean you're on a go-around!
You'll find them set in the CL gate because that's were you've set them yourself shortly after take-off... Remember, they haven't moved even half an inch during the flight.
All you need to do is to set the throttles so as to match your current thrust setting as depicted on the white dials and push the red disconnect buttons on the left and right side of the throttles.
You know have full control over your engine within its FADEC protection limit.

Of cource I understand your real question here:
How do I find the correct throttle position with would give me exactly my actual thrust setting, since my thottles aren't moving along as on Boeing planes.
In other words:
if I disconnect the A/THR and the setting I've set does not match the curently set value, will I have a jump in thrust?
YES!!!
BUT:
On the Primary Engine Display you'll find on the white dials a sort of bug which exist only on Airbus planes: it is a small white circle and it displays the predicted thrust setting corresponding to your current throttle position.
All you have to do is to bring the small white circle around the pointer representing the actual thrust setting before disconnecting the A/THR to avoid a jump in thrust.



Is that easy or what?







User currently offlineGreenArc From United States of America, joined May 2000, 78 posts, RR: 1
Reply 13, posted (13 years 2 months 1 week 5 days 20 hours ago) and read 6242 times:

>>Is that easy or what?<<

AT Disconnect Procedure:

Airbus

1) Abandon what you were doing (hopefully not important) and move eyes to engine instruments
2) Pull throttles out of CLB detent
3) Match little white circle thingy to little thrust marker thingy (which may be moving)
4) Push autothrust disconnect button
5) Readjust throttle angle if you missed thingy in step 3

Boeing

1) Push autothrottle disconnect button

Easy? Sure. As easy? Not really.

GreenArc



User currently offlineA320FO From Austria, joined Oct 2000, 211 posts, RR: 1
Reply 14, posted (13 years 2 months 1 week 5 days 12 hours ago) and read 6247 times:

Just a few further comments

@sxmarbury33
Sabenapilot gave a good description of the system. I just want to add, that if the trust levers are in the TOGA or FLEX gate (with bth engines running), the autothrust system is not acitve, it is only armed. So you are always operating at a fixed thrust setting. Once the thrust levers are moved to the CLIMB detend, the autothrust system is activated and the thrust lever position gives the upper thrust limit for the autothrust system. If an engine failure is encountered, the autothrust system becomes active up to the MCT detent, which is the same as the CLIMB detent.

@ GreenArc
Yes it is that easy.
Just some examples the other way around.
Set climb power:
Airbus: Keep looking outside for traffic, just pull the levers back one or two detents.
Boeing: Stop everything else, look at the gauges, find the climb thrust value, set the levers accordingly. Look outside again.

Go-around:
Airbus: Just slam the levers forward into the TOGA gate
Boeing: Stop everthing else, look inside, carefully push thrust levers forward, don't overboost engines, look outside again. Or: start searching the TOGA-levers hidden somewhere on the thrust levers, pull them.

Now, before somebody starts to bash me because I am apparantely bashing B*****. I intentionally exaggerated a little. After some time on the airbus, you get a feeling where to put the thrust levers when disengaging the autothrust. So you pull the levers back, take a quick look to readjust, then disconnect.
When flying, I tend to disconnect the autothrust when deccelerating the aircraft, with thrust idle conditions. So all that you have to do is pull the levers back all the way and disconnect. The idle thrust condition can be checked without your view ever leaving the PFD (primary flight display), as it is shown there.

A320FO


User currently offlineSabenapilot From Belgium, joined Feb 2000, 2714 posts, RR: 47
Reply 15, posted (13 years 2 months 1 week 5 days 12 hours ago) and read 6234 times:

GreenArc-

About your 5 step concept:

First Point:
When you're about to start handflying you better abandon everything else anyway or you'll be in big shit soon, I can assure you!
As for point 2 and 3:
This is done simultaneously and goes very quickly. Again: if you don't like to move the throttles, then you shouldn't start flying manually at all! The A/THR system can very well remain engaged till after landing.
Point 4:
Has to be done on all planes if you want to disconnect, so this is no extra manipulation at all!
Point 5:
It may come as a surpirse to you, but no adjustement will be required to finetune! The only time you will have to adjust the throttles is when you want to change the thrust, not when you want to match your bugs; this is done electronically.

Airbus calls its system not for nothing A/THR (Autothrust) i.s.o. A/T (Autothrottle):
An A/T is a mechanical system.
The A/THR is an electronical system.


User currently offlineSabenapilot From Belgium, joined Feb 2000, 2714 posts, RR: 47
Reply 16, posted (13 years 2 months 1 week 5 days 11 hours ago) and read 6229 times:

Hi there A320FO,

As you know I have also flown the B737, so I can give you a brief explanation on how we worked with the A/T system on the Boeing :

When entering the runway the A/T is switched on.

When cleared for take-off the captain pushes the throttles forward and then clicks the TOGA buttons to set the TO thrust.

At 1500AGL the "CLIMB" mode is engaged by pushing CLM on the glareshield and all will be set as on the A32X.

We stay in CLM for the rest of the flight, but with the throttles moving. You hardly notice this unless during the level off, where you'll see them move backwards quite a lot.


Nothing to worry about untill the descent:
During descent we have to select the level change (LVL CHG) mode on the Glareshield resulting in the throttles moving all the way to idle and the plane pitching down to keep its speed. In other words: the A/T is controlling our descent.
CAUTION: If the RoD is to big, we have to push the throttles up against the A/T! Some piece of automation, hey?

The alternative to this is to select the V/S mode for the descent.
Here A/T is controlling only speed rather then our full descent but in doing so has a lower priority then the VS mode!
CAUTION: This method is only safe to do when we start our descent early! It was not a good thing to do when high on descent profily! Why? When high, you'll increase the V/S to get back on profile, but as a result the A/T will retard completely to prevent us from speeding up. However, when the throttles reach idle, VS has priority over the A/T, so the VS will be kept and the plane will speed up with the A/T engaged!
This is not a theoretical situation BTW, is happened quite often, especially with engine and airframe anti-ice on and a RoD of over 2500fpm. In other words, just when you're in a quick IMC descent your system might not do as you tell him to do.
Again, What kind of automation is that, hey?


User currently offlineGreenArc From United States of America, joined May 2000, 78 posts, RR: 1
Reply 17, posted (13 years 2 months 1 week 5 days 3 hours ago) and read 6221 times:

AF320,

I was obviously exaggerating as well. My point is that the Airbus system has substituted operational complexity for mechanical complexity and removed the pilot from the thrust loop. A modern moving throttle system is far superior in terms of usability. Both get the job done. One allows the pilot much greater situational awareness.

>>Boeing: Stop everything else, look at the gauges, find the climb thrust value, set the levers accordingly. Look outside again.<<

I was referring to something more recent than the 707. All I do is say VNAV and the PNF pushes the button.

>>Boeing: Stop everthing else, look inside, carefully push thrust levers forward, don't overboost engines, look outside again. Or: start searching the TOGA-levers hidden somewhere on the thrust levers, pull them.<<

I do consider the Airbus go around action to be more instinctive. But again, I don't know what old airplane you're talking about. Pushing the TOGA button is all that is required.

Sabenapilot:

>>When you're about to start handflying you better abandon everything else anyway or you'll be in big shit soon, I can assure you!<<

Excuse me while I rebook my flight to Brussels!

GreenArc


User currently offlineA320FO From Austria, joined Oct 2000, 211 posts, RR: 1
Reply 18, posted (13 years 2 months 1 week 5 days 2 hours ago) and read 6211 times:

:D
See, we're up to the same thoughts. Whatever system, moving or not, is just a matter of getting used to. Once you build some experience on it, you use it with ease. Yes, I was refering to older style systems....
Flying the A320, I don't consider the system being complicated in terms of usage. I also don't feel being out of the loop. If I handfly, well, I handfly. There's no difference. In cruise, nobody has a hand on the throttle anyway.

Take care,
A320FO


User currently offlineSabenapilot From Belgium, joined Feb 2000, 2714 posts, RR: 47
Reply 19, posted (13 years 2 months 1 week 4 days 22 hours ago) and read 6199 times:

A320FO,
In cruise, nobody has a hand on the throttle anyway.
That's absolutely right!
By doing so, most of us get what I call a paralised hand.
It's there all right, but we don't feel anything with it.

I can tell you a nice story about that.
During CATII/III approaches the Sabena B737 SOP calles for the F/O (who's always the PF) to have his hand on the throttles, fingers ready at the TOGA in case of a go around. Since your hand is on the throttles you should be able to feel all movements and spot any abnormalities right away, isn't it? At least that's what someone claimed here on this forum (and what I used to think as well...)
NO WAY:
During my first sim recurrent I ran into an instructor who liked to show us just how much we really notice what our hand feels when it is on those thottles.
This is what he did during the biannual low visibility approach revision session. (Low vis approaches mean we always have both A/P and A/T on for the approach, although legally you can do it without A/T)
The plane was nearing the FAF with Gear down, F15, speed 170kts and so the captain (always PNF) asked for the latest RVR (legally required for the approach ban) while I was flying through the A/P and A/T.
RVR was just about right, so we continued the approach, and shortly before the marker we selected F25 and a slower speed (140kts) on the glareshield.
All came out nicely and the A/T put our throttles in idle to give us the lower speed.
The captain then did his airswitching (to avoid bleeding air from our engines reducing our go-around performances) and started going over the landing checklist.
At that moment the instructor failed our A/T.
The plane approached the set speed of 140kts so I called for F30 then F40 and Vtarget.
The plane was decelerating and I had my hand on the throttles (with the failed A/T which none of us noticed although it was failed for 20 sec now)
The landing checklist was completed and the plane neared the Vtgt at around 500AGL.
However, unlike usual, the A/T did not bring up the throttles to keep vtarget. Instead we kept on decelerating quite fast!
None of us noticed anything weird about our thrustsetting nor about the speed and it was only at vtgt-15 kts that I spotted our speed was way too low. A go-around was initiated but stickshaker was encountered anyway, because I tried to start the go-around by clicking the TOGA buttons, not realising the A/T had failed!
A manual go-around was flown and we got out of this safely, but I must say that I didn't step out of that simuator happy that evening.
Stickshaker at less then 200 AGL in IMC is not good for your health!




User currently offlineSxmarbury33 From United States of America, joined Oct 2000, 445 posts, RR: 0
Reply 20, posted (13 years 2 months 1 week 4 days 22 hours ago) and read 6194 times:

To sabena pilot just two more questions during your decent profile you said you used FL chng for your decent or VS. How come you dont use vnav? If your profile gets to high it will automaticlly switch into a FL CHNG like mode where the flight mode anunciator on the EADI will say Idle/AT. Isnt that esier then using FL chng and VS. And one more thing in the 737 dont you get a audible warining and a master caution above the glarsheild if the autothrottle fails?

User currently offlineSabenapilot From Belgium, joined Feb 2000, 2714 posts, RR: 47
Reply 21, posted (13 years 2 months 1 week 4 days 21 hours ago) and read 6191 times:

VNAV is not really easy to use in Europe you know, especially not when they vector you in.
If you use it you'll end up reprogramming your FMS about every minute, so its better to take it out of the loop and give descent instructions via VS or LVL CHG.

On the B737 there is a master caution above the glareshield for an A/P failure. If that is lit, you have 2 seconds to push the TOGA buttons, or else the A/P disconnects.
Sadly you do not have this kind of safety device for the A/T, basically because you are certified to fly low vis approaches without A/T.


User currently offlineGreenArc From United States of America, joined May 2000, 78 posts, RR: 1
Reply 22, posted (13 years 2 months 1 week 4 days 20 hours ago) and read 6188 times:

Sabenapilot,

It's been a while since I flew the 737, but I recall an A/T failure alert (at least on the -300 or better). But, I am sure there are unalerted failure modes, so the scenario your instructor shared might be possible in the real world.

However, I find your story more of an endorsement of moving throttles than a case for their removal.

>>None of us noticed anything weird about our thrustsetting nor about the speed and it was only at vtgt-15 kts that I spotted our speed was way too low.<<

All the signs were there and you ignored them; stabilized in IMC conditions, you should have been spooled up far before reaching 200'. Instead, you apparently watched the speed decay while ignoring the fact that the throttles (and your attached left arm) weren't travelling forward to compensate. Shouldn't the throttles be off the stops at 40 flaps, stabilized and on target?

I have to ask: How would an unannunciated failure of the autothrust system on the Bus been easier to detect?

GreenArc


User currently offlineSabenapilot From Belgium, joined Feb 2000, 2714 posts, RR: 47
Reply 23, posted (13 years 2 months 1 week 4 days 11 hours ago) and read 6185 times:

GreenArc,

When our A/T popted out in the scenario I gave you, all we could have noticed was:
-) a small clicking noice.
-) the A/T switch to off on the Glareshield.
-) no more A/T green status.
I know this should be more then enough to spot the A/T being off, but after 3 hrs of sim recurrent including all kinds of abnormals and emergencies to deal with, your head is so blown up by alarms, bels, chimes etc, that such a small defect goes unnoticed for quite a long time. (half a minute or so)
We should have seen this, I should have done that, the captain should have said something etc. etc. Fact is we didn't, and the instructor assured us we were not the only ones.

In no way my example was a statement pro Airbus, it was purely to show that the idea of moving throttles being better to keep pilots in the loop is just an illusion to me. I experienced for myself that a hand might feel the movements, but not my brains.


User currently offlineWing From Turkey, joined Oct 2000, 1559 posts, RR: 24
Reply 24, posted (13 years 2 months 1 week 4 days 7 hours ago) and read 6171 times:

I've read whole thread was a quite interesting topic.I have to congradulate the topic starter which I can't see more topics turning into nice informative threads.I have two things to say.The first one to Sxmarbury33;I was thinking about this today in a boring Algebra class Why does the 320/330/340 series and maybe more im not sure have auto throttles that dont move.I know I'll sound like parents,but you look like very imterested in being a pilot so I suggest instead of thinking about Airbus throttles in algebra lessons,try to fix on your lessons because the way to an Airbus or a Boeing cockpit unfortunately passes along the algebra class.The less time you loose on school the fastest you start achieving your goal.Once again I don't wanna sound like parents but giving you an advice which worked fine with me,assuming you want to be apilot.
The second is about the Sabena pilot's simulator story.Me, being fresh out of simulator to convert -400 to -800 licence, ,"Fact is we didn't, and the instructor assured us we were not the only ones."You don't have to explain any excuses.I can very much understand how tired you feel (not only your body but your brain more than that)after a long period of a simulator session and sometimes can't notice even the more obvious signs.Been there,done that and seen others do it too.(Even the guys much more experienced than me)Thats the reason why the simulators are for.We have to do some mistakes to learn not to do them on real life,and its very easy to criticize and say "All the signs were there and you ignored them"by just reading from a post not at the time you experience it.(I mean my intension is not to disrespect the experience of any other fellow pilot but just thinking that its much easy to talk about somebody elses experience if you are not under the same conditions)Best Regard and safe flights to you all.WING



Widen your world
User currently offlineSabenapilot From Belgium, joined Feb 2000, 2714 posts, RR: 47
Reply 25, posted (13 years 2 months 1 week 4 days 5 hours ago) and read 6177 times:

Thank you Wing.
I think this is the end of this topic then.
I hope to meet you all again in a new topic soon.


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