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Airbus trepidation... convince me otherwise!

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Airbus trepidation... convince me otherwise!

Old 16th Jan 2012, 14:49
  #141 (permalink)  
 
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Just to be 100% clear: You are trying to say that if an aircraft does the complete opposite of what you just commanded it to do and reduces thrust to idle when you require (and have commanded) full thrust, that is not 'working against you' in your book?
Since they never disconnected the autothrottle, technically (and practically, which is case in point) they didn't command anything. The autothrottle was still in command.
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Old 16th Jan 2012, 22:21
  #142 (permalink)  
 
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@cosmo:

Since they never disconnected the autothrottle, technically (and practically, which is case in point)
they didn't command anything. The autothrottle was still in command.
So in fact........the boeing is a 'pilots plane', but only after disconnecting the automatics
and the airbus automatics follows pilot command....but still isn't a 'pilots plane'...
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Old 16th Jan 2012, 22:36
  #143 (permalink)  
 
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Hi
As you pull out you see a car approaching so you step fully on the accelerator pedal. But the car instead applies the brakes.
Er no. They stepped on the accelerator pedal briefly, whilst cruise control was still engaged, then took their foot off the pedal and were surprised with the result.

ASN Aircraft accident Boeing 737-8F2 TC-JGE Amsterdam-Schiphol International Airport (AMS)

"The first officer responded immediately to the stick shaker by pushing the control column forward and also pushing the throttle levers forward. The captain however, also responded to the stick shaker commencing by taking over control. Assumingly the result of this was that the first officer’s selection of thrust was interrupted. The result of this was that the autothrottle, which was not yet switched off, immediately pulled the throttle levers back again to the position where the engines were not providing any significant thrust. Once the captain had taken over control, the autothrottle was disconnected, but no thrust was selected at that point. Nine seconds after the commencement of the first approach to stall warning, the throttle levers were pushed fully forward, but at that point the aircraft had already stalled and the height remaining, of about 350 feet, was insufficient for a recovery."
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Old 16th Jan 2012, 23:42
  #144 (permalink)  
 
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just a follow up question

Er no. They stepped on the accelerator pedal briefly, whilst cruise control was still engaged, then took their foot off the pedal and were surprised with the result.
With this comparing of A vs B for this particular event, what would have happened with the Airbus if they did the same thing , advance the throttles
,which would be set at CLB and probably be forwarded to MCT as far as I know, and subsequently not follow up on that action like they did with the Boeing ?
Would the outcome have been the same ?
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Old 17th Jan 2012, 03:01
  #145 (permalink)  
 
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Seems to me that you might be able to see the other pilots stick inputs based on this video(ignore the title) -

Watch This If You Are Not Scared of Flying
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Old 17th Jan 2012, 03:32
  #146 (permalink)  
 
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If the autothrottles are not doing what they are supposed to do turn them off and manually put the thrust where you want it.


I mean, seriously, does a Pilot really need to be told that ?



The Amsterdam crew had their head's up their a**e
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Old 17th Jan 2012, 08:35
  #147 (permalink)  
 
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Originally Posted by stilton View Post
If the autothrottles are not doing what they are supposed to do turn them off and manually put the thrust where you want it.


I mean, seriously, does a Pilot really need to be told that ?



The Amsterdam crew had their head's up their a**e
At least one did, but it may not be fair to say all of them did.

PF was advancing throttles and pushing stick forward (IIRC) within a second of stick shaker - then his captain told him to leave off, and crashed the plane.

PF might not have had enough height & luck to recover, but he was doing the right thing before he was told to stop.
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Old 17th Jan 2012, 13:48
  #148 (permalink)  
 
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Originally Posted by misd-agin
Seems to me that you might be able to see the other pilots stick inputs based on this video
Because a wide-angle camera has been set by the pilots on some strategic places but absolutely not representative of what a PNF or jumpseater would naturally see.
It is an excellent video. Interesting to see the trim moving, something you rarely notice when scanning the instruments or looking outside, especially in manual flight.
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Old 17th Jan 2012, 15:26
  #149 (permalink)  
 
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J/S'd on an A320 last year and leaned forward so that I could watch the FO's stick inputs. Trying to get a feel for how much control input was needed vs. the airplane's response.

He moved it a lot less than the pilot did in this video.

Actually had his fingers around the stick like you'd hold a wine glass. It wasn't a full fist like grip. Interesting to see.
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Old 18th Jan 2012, 00:28
  #150 (permalink)  
 
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Actually had his fingers around the stick like you'd hold a
wine glass. It wasn't a full fist like grip.
Indeed - the driver in that vid was grabbing the stick like a
virgin holding her first appendage. One can accomplish the same
sequence with light finger inputs only.
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Old 18th Jan 2012, 13:34
  #151 (permalink)  
 
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Too many pages...i can't read all of them.

Not sure if anyone said the same thing.

Was a Boeing man before switching to Airbus.

My only advice to you, Don't compare.

If you want to fly an Airbus, then do it the airbus way.

Comparing it with a Boeing will make the transition very very difficult.

Good luck.
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Old 19th Jan 2012, 06:19
  #152 (permalink)  
 
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Neupielot
That's the best advice I've seen here. They are two entirely different beasts and if I had a dollar for everytime someone has said "in the Boeing we did it this way" during Airbus type ratings I would have retired from training years ago!
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Old 6th Feb 2012, 00:19
  #153 (permalink)  
 
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One hand should always be on the thrust levers inside the FAF. Since the TLs on the Boeing move he would have felt the movement towards idle and responded.
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Old 6th Feb 2012, 17:48
  #154 (permalink)  
 
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Hand on Thrust Levers not part of Airbus Philosophy

By making the design choice not to have the thrust levers backdriven during autothrottle operation, Airbus has declared that a hand on the thrust levers plays no role in monitoring their system. "Hand on the thrust levers" has been replaced for these airplanes by "eye on the engine instruments".

In general, the Airbus design approach renders all tactile feedback meaningless. As a result, it is more difficult for crew on an Airbus flight deck to keep themselves in the loop than on a flight deck where the throttle levers and the pitch/roll controller inputs are backdriven and coupled.
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Old 6th Feb 2012, 22:41
  #155 (permalink)  
 
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SLF here and a lifelong well-read enthusiast/spotter. Simmed when I was younger and read all I could find - from performance/procedures of all modern jets and ALL accident/crash reports.

Have flown on B 722, 732, 742, 743 & A 300B4, A300-600 (in real life).

IMHO, both companies produce aircraft to be respected.

If one don't understand philosophy, let me know before I board.

P.S. Definite difference in handling A vs B, but same with cars.

All my respect.

Mike X
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Old 7th Feb 2012, 14:37
  #156 (permalink)  
 
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Smile

But... I still question: Are the pilots REALLY in control?
Yes. Transition to the Airbus family is a tad "different" at first, as with any new thing.
As you get on with it, you realise how you are going to fly this thing. there are new rules to flying, its fly-by-wire for a start, it has different laws for another it has managed and selected inputs to differentiate - bottomline, you are always in control because you always know what it is going to do next or indeed what to do if it "supposedly" decides not to play ball - (rare). So long as you learn everything about the aircraft - and more importantly - keep on learning, it is a nice bit of kit. you will never get the feel you get with a conventional aircraft - but if you assimilate all the knowledge and get used to setting it up and its characteristics of attiude being maintained by leaving the stick in neutral and other aspects pertaining to the Airbus family (most of them) you will find the A319 to be a babe to fly - just adapt, after studying like a b-----d! . . . and, as Stilton rightly said -

If the auto whatever doesn't work, just fly the bl**dy aeroplane.

Last edited by Natstrackalpha; 7th Feb 2012 at 14:41. Reason: Forgot the last bit
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Old 7th Feb 2012, 14:47
  #157 (permalink)  
 
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Smile

In case some of you didn't see this article when it was first posted:

Technique: The 'Panic Pull'
this "anomaly" wouldn`t occur if those `pilots` or whatever they call themselves had the proper R.U.A. training and if anyone does not know what R.U.A. means then it is time to get on a course, without delay.
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Old 22nd May 2012, 16:10
  #158 (permalink)  
 
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Geez Natstrack you must be the Boss in general of super high intensity training.
And in case you dont know THAT acronym......

come to think of it you propably are full of such training
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Old 22nd May 2012, 17:07
  #159 (permalink)  
 
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You don't need to trim out the control forces on an Airbus, because there aren't any ! It's just a joystick connected to 5 computers.

The main thing no-one ever tells you is that the autopilot arrangement is different to a Boeing. When you disconnect the autopilot in a Boeing, your control inputs then go directly to the control surfaces. (Don't know about the 777 or NG). In an Airbus, the autopilot is always in !! When you disconnect the autopilot in an Airbus, what you are actually doing is changing where the autopilot receives its guidance from: The FMGS/FCU, or your sidestick. The autopilot is still in circuit, keeping the aircraft flying where you put it (and keeping it trimmed) - which reduces the control inputs required from you. All you need to do is 'tell it' where you want it to go. The Airbus will keep the attitude you command, even through turbulence. (Although severe turbulence or upsets will require corrections from you).

Don't hose the side stick around, just make small corrections to keep the box on the cross hairs and the Airbus will do the rest. In windshear or strong cross winds, you may need to hold full sidestick for several seconds, but it will respond and this is fine once you're used to it.

I do think however, that they should have made the side sticks move together, so the other guy knows what you're doing and vice-versa.

Regarding moving auto throttles, the Airbus system is very easy to fly. Your scan will soon modify itself to look for the thrust clues rather than feeling them through your hand.

Good luck - it's a wonderful machine !

Last edited by Uplinker; 22nd May 2012 at 22:04.
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Old 22nd May 2012, 18:40
  #160 (permalink)  
 
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Sorry Uplinker, but your statement is partially inaccurate. I believe the AF447 pilots also would have made the same statement which I believe is the ultimate flaw in Airbus by design. In NORMAL law there is no need to trim out the control forces, however when in direct law then yes you do need to trim out the forces and not only that but there is no force on the stick! So you have to trim the aircraft with absolutely no feedback from the stick! As an Airbus pilot I would never just consider what is accurate when the aircraft is in normal law but I must consider Alt with prot and Alt without plus direct law. 4 different logics (which totally confuses people even to this day - and quite rightly as it's ridiculously over complicated).

"The airbus will keep the attitude you command, even through turbulence". Erm, no it wont! It will command 1g. If the pitch changes, it will still command 1g, so no that is a factually incorrect statement. Take your hand off the stick on approach, yes it can be very impressive and hold the attitude for all of 10 / 15 seconds on an ABSOLUTELY clear day. However add any variance (which as you know is always there) and you have to make an input. Large or small, its an input. I agree, it does reduce the control inputs required but to say the aircraft will keep the attitude you command is simply not true (which you allude to by saying FULL stick may be required in strong crosswinds etc).

Your statement re modifying your scan to include the engine instruments is (yes, in my opinion) another flaw with the Airbus design. WHY remove something which you can monitor easily. No, it's not difficult, however what is the point? What is the purpose? You could make it easier and arguably improve pilot SA by having moving thrust levers - there is no argument that pilot SA is improved by removing moving thrust levers! In fact I believe the original Airbus idea was to have absolutely no thrust levers at all and have buttons instead!

I still fly the Airbus and I enjoy it. I agree, it is a wonderful machine. I do also feel however that Airbus have tried to oversimplify being a pilot by removing things that were actually quite useful (moving thrust levers, linked moving sidesticks).

Last edited by wheelie my boeing; 22nd May 2012 at 18:42.
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