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Automation Bogie raises it's head yet again

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Automation Bogie raises it's head yet again

Old 5th Jan 2011, 15:11
  #81 (permalink)  
 
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Originally Posted by Melax
Makes you more humble, there is absolutely no substitute for the basics
Chilling reading how the picture can change. The comment that the elevator feel units were spoofed by the incorrect ASI readout and allowed +5G acceleration to be achieved with only a modest pull on the control column.
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Old 5th Jan 2011, 15:31
  #82 (permalink)  
 
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A37575: My point exactly. "Unless the correct amount of corrective rudder is fed in to counter yaw, the control wheel then turns automatically to hold the ILS localiser. This causes inevitable flight spoiler operation and thus unwanted drag. The whole event can then turn into what is beautifully described as a horses's arse."

And that is because of crossed controls.Teach the drivers to do it properly. Allowing cross controls during autopilt useage is bad piloting; it is not a reason not to use all aids at your disposal. The use of automatics is to reduce the workload and improve oversight of the operation. This is true in normal & non-normal ops. If the automatics are doing a bad job it does not mean it is the fault of the automatics.
For a SE ILS, if the rudder is trimmed correctly it will be the same for all configurations except when reducing thrust to slow down for more flaps. A little opposite rudder for a few seconds should not be beyond the wit of most. Thrust control is no more difficult than a manual approach. Mis applied rudder with autopilot on is obvious by looking at the aileron defelction.

Your comment about turning base I see all the time, but that is because people extend flaps in turns. Reduce thrust with no rudder input. If you increase thrust 3% then turn there is no need for rudder input and everything is smooth. SE turns in constant config is highly recommended and SOooo much easier.

It reminds of 1 airline I flew for on the classic years ago. In London TMA there were many step climbs of 1-2000'. On B767, years before, they had introduced a PIP software which, in LVL CHG gave a gentle climb for such small adjustments. The classic just went full power and screamed up. Those of us 'in the know' used V/S 1000fpm and taught it. The HOT did not like this as many pilots did not know the gotchas of V/S. He banned it and insisted on KISS, the use of uncomfortable LVL CHG. Guess what; with TCAS, and RVSM, it is now Eurocontrol SOP. So rather than train guys how to do it properly it was banned. Is that the correct attitude? Know what does what and know how to use it, then choose the best. Ignorance will bite you hard. I still see guys playing the piano on the AFDS trying to find the correct button to make happen what they want. AND they still look at the button and NOT the FMA. Detailed good complete training will always go a long way. It's the diluted version which will cause problems later.
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Old 5th Jan 2011, 16:54
  #83 (permalink)  
 
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Airbus manual flying in normal law relies heavily on automatics, and the switches also known as the thrust levers give no positional feedback when used in auto. When things go awry, therefore, it’s quite a big jump in workload to fly the aircraft in alternate or direct having only practiced what is essentially controlled stick steering for normal manual flying; and putting the control levers back to the approximate position they were in prior to disengagement is a non starter. It must have all looked so splendid and modern on the designers' desk. Hey ho.

Just back to edit a typo, and for d105 below, not sure an airbus would suit you!

Last edited by blimey; 5th Jan 2011 at 17:15.
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Old 5th Jan 2011, 17:00
  #84 (permalink)  
 
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Out of interest. Which 'gotcha's' could occur using V/S in a 1000 feet step climb?

From your post I conclude both A/T and A/P were being used as you state LVL CHG would have the aircraft push it to full thrust.

So with both those engaged I fail to see what could happen in a 1000 fpm step climb. Unless you somehow start to retract your flaps in that climb without accelerating to up speed first.

Unrelated question for the Airbus drivers. When you fly your aircraft manually is there a difference in responsiveness in relation to speed?
On the 737 when you descent at 330 KIAS while flying manual the slightest movement on the yoke has the aircraft reacting to it immediately. As you slow down to UP speed the reaction of the aircraft to your inputs becomes more sluggish.

Is this simulated in the Airbus joystick? Or does the joystick feel the same at VMO and VCLEAN ?

Control feel is personally my first indicator something is wrong. If I would feel the aircraft becoming heavy in the nose but my trim is near 5° and my ASI indicates 320KIAS, then I know something is up.
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Old 5th Jan 2011, 18:36
  #85 (permalink)  
 
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The issue appears to be automation, but more so, advanced technology - automatics only provide muscle for some applications.
A view from previous discussions was that we have to live with ‘it’ (I stress ‘it’ as automation/technology); we have to get used to it, it’s a fact of modern operations. Some people are managing this, perhaps some not, and for the majority there is an uncomfortable in-between state with many pitfalls, often creating a feeling of ‘not being in control’.

Many safety problems involve ‘technological malfunction’; this is rarely due to a system fault, but more likely aspects of human interaction – not understanding the situation (including the technology) or not choosing an appropriate course of action.
As much as we think that we understand technology, most initial training only covers the basics of normal operations without serious ‘malfunction’, and don’t forget a ‘self’ malfunction.
Current automation adds complexity which furthers the need for evaluation, understanding, and choice; this requires greater operating knowledge which may only be acquired ‘on the job’.

Are we – the industry and individually, learning ‘on the job’? Is there encouragement (there’s no requirement), opportunity / time, personal willingness, or guidance / instruction available for this?
IMHO we are failing to learn about operating automation. Where we do learn, and a lot is accomplished in operation, it may not be directly relevant to the situations we face, or we are not learning in-depth to satisfy the needs of safety.

With modern automation/technology we appear to require more time to acquire knowledge in order to operate in the same manner as previously.
Thus calls for more training; but alternatives could be to change the operational environment, or the nature of the operation. The most likely solution is a combination of both, involving new ways at looking at training, operations, and particularly ourselves.

Many of the answers are within the ‘bleats’ about auto/manual flight. Stop and think about what ‘you’ can do about ‘it’, think about operating without technology, the basics of assessing the situation, understanding and planning without an ND / FMS. Prepare yourself for the unexpected - how you would manage the aircraft in a LHR hold without FMS / autos; it’s not just stick and throttle flying. Then with these skills automation might appear more logical.

“Give a starving man food today and he will be hungry tomorrow, teach a man to farm and he will feed himself” - - - Teach a pilot to operate / manage (think) as well as handling skills, then you provide a basis for future safety, new captains, and instructors.
Yes – there’s a gap between effecting any change and the reality of now – we have to ‘think’ about that ourselves – how do we operate and what do we know – or don’t know (what and how), and what are we going to do about that – professional self improvement. The industry won’t do that for you, these qualities cannot be regulated or inspected; they have to come from within.
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Old 5th Jan 2011, 19:48
  #86 (permalink)  
 
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BUSS option

Over a year ago Airbus offered the airlines to buy an extension to their software that would help the pilots in situations where airspeed were unreliable. The software add-on was called BUSS. BackuUP Speed Scale, that replaces the pitch and thrust table. BUSS is said to be optional on A320, A330 and A340 but included in the basic software for A380 as part of the ADR monitoring functions.
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Old 6th Jan 2011, 00:32
  #87 (permalink)  
 
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V/S

D105
If you don't know the "gotcha's" with regards to using V/S in a step climb, then I never, ever want to be on your aircraft.
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Old 6th Jan 2011, 01:57
  #88 (permalink)  
 
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But in the 737 Classic, the autopilot-flown single engine instrument approach, is neither fish nor fowl. The remaining throttle is operated manually and so are the rudders; while the ailerons and elevators and stab trim are on autopilot. In the simulator for example, we see the situation where the pilot changes the thrust manually to correct a speed trend. In turn, he then has to adjust the rudder position to correct for yaw.

Unless the correct amount of corrective rudder is fed in to counter yaw, the control wheel then turns automatically to hold the ILS localiser. This causes inevitable flight spoiler operation and thus unwanted drag. The whole event can then turn into what is beautifully described as a horses's arse. And that is because of crossed controls.

The 737 is perfect for picking up deficiencies in knowledge/training/skill due to this.

Most of the problems I have observed in the sim seemed to be due to pilots treating the autopilot as a 'pilot', rather than a tool to assist. This comes about for a number of reasons including laziness, lack of knowledge of A/P limitations, being overloaded, lack of adequate training or simply, incompetence - they need the A/P to do it for them because they can't do it themselves.

Once they have engaged the autopilot, some pilots seem to be under the delusion that they don't have to fly the aircraft anymore because they have handed control over to another 'pilot'. They then spend their time focusing on checklists & trying to make decisions, while the ailerons are getting further & further towards the stops &/or the speed is rapidly decreasing.

What you usually end up with is the aircraft turning in the oposite direction to what is commanded by the heading bug & the pilot then saying "what's it doing?" & "the autopilot isn't working properly". He/she then disconnects it, which usually leads to immediate flight path control problems, particularly if the speed has become dangerously low.

Know what does what and know how to use it, then choose the best. Ignorance will bite you hard. I still see guys playing the piano on the AFDS trying to find the correct button to make happen what they want. AND they still look at the button and NOT the FMA.
Absolutely correct RAT 5! Most pilots don't seem to realise that pushing the button on the MCP is the third step in the process, not the first. You have to first decide what you want or need to achieve, then work out how you are going to use the various A/P modes to acomplish that, & only then, do you move to the MCP to engage the required mode.

And I agree, you must always, always, always check the FMA. Pushing the button is what you want; what is on the FMA is what you have got.

Again it's lack of knowledge of the system &/or lack of training in how to use it properly.

As for V/S, a lot of pilots seem to be either unaware of the appropriate time to use it, or scared of using it at all. Also, Flight Level Change seems to be the only mode some feel comfortable using during descent, even to the extent of using it instead of VNAV Speed when something has changed the descent profile. They don't seem to grasp that, put simply, VNAV Speed is Flight Level Change with some of the protections of VNAV path.
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Old 6th Jan 2011, 09:19
  #89 (permalink)  
 
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but then again...

CMD , VOR/LOC, 110.30 will in all probability take you down the centerline of ONE particular runway and preferably the one the ATC wants you to be on.

AP off, AT off, FD off :: you MIGHT bring in both the parallel runways, both the parallel taxiways the next door Airforce base and a local highway into the equation.
Now dont tell me that hasnt happened before!
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Old 6th Jan 2011, 13:25
  #90 (permalink)  
 
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AP off, AT off, FD off :: you MIGHT bring in both the parallel runways, both the parallel taxiways the next door Airforce base and a local highway into the equation.
Now dont tell me that hasnt happened before!
Only if you lack situational awareness. Only you will know that - not the auto pilot....
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Old 6th Jan 2011, 14:45
  #91 (permalink)  
 
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A3757 is quite right. Situational awareness is key. I wonder how many ''automated'' pilots bother to identify the localizer frequency. Garbage in Garbage out.

Oh, and that NW Airbus that overflew Minneapolis...it didn't take care of itself.

I do think one problem with autopilot use, especially in emergency ops in simulator training is this. .Union contractual language doesn't allow for compounding emergencies during check rides. Lose an engine and they can't fail the autopilot on you...in the sim. But in real life, well that's different.
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Old 13th Jan 2011, 13:50
  #92 (permalink)  
 
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Well Sun Orbital, how about you enlighten me than?

Perhaps I'm not as schooled in use of V/S for a 1000ft step climb as you. Maybe that's due to the fact that, when I am in command, the aircraft will actually be under manual control

A37: If you need to Autopilot to perform a basic flight manoeuvre you should be stripped of your license.
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Old 13th Jan 2011, 15:06
  #93 (permalink)  
 
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I can only imagine that the GOTCHAS in using vertical speed in a climb is that if you select a vertical speed beyond the energy capabilities/ceiling capabilities/ that you might stall.

I seem to recall a Mexicana DC10 that stalled due to inattention in this mode...is that what you meant?

of course selecting mach hold/IAS hold can result in a climb that is protected against a stall, but the nose can ''hunt'' if there are airspeed vagueries.
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Old 13th Jan 2011, 15:11
  #94 (permalink)  
 
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sevenstrokeroll:

I wonder how many ''automated'' pilots bother to identify the localizer frequency. Garbage in Garbage out.
I haven't flown the state-of-the-art avionics. I know they display the identifier of the selected LOC or VOR. If that is displayed only after the avionics have "listened" to the identifier, then wouldn't that make it unnecessary for the "automated pilot" to take the time (and attention diversion) to concentrate on the Morse Code audio?
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Old 13th Jan 2011, 15:49
  #95 (permalink)  
 
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757/767 do not automatically display left and right ILS frequency on the 'map' mode. You set the center ILS and it tunes the left and right ILS. It's up to each pilot to then switch their nav display to the ILS mode to verify the correct frequency for their respective ILS.

Randomly the center ILS will not correct tune the left or right ILS. It's a problem with what the center ILS is displaying for a frequency vs. what is actually being tuned. You then have to adjust the center ILS frequency selector until the left and right ILS's have the correct frequency.

SOP's cover this - tune center ILS, verify on respective nav display by selecting ILS mode, verify via morse code.
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Old 13th Jan 2011, 16:04
  #96 (permalink)  
 
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AND they still look at the button and NOT the FMA.
Reminds me of a couple of classic phrases from my instructor on my first electric jet:

"The MCP is the Rumour Panel. The FMA is the Truth panel."

and, regarding Magenta/Managed vs White/Selected:

"White Rules"

(with an extra bit of irony: he was South African.)
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Old 13th Jan 2011, 17:11
  #97 (permalink)  
 
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I can only imagine that the GOTCHAS in using vertical speed in a climb is that if you select a vertical speed beyond the energy capabilities/ceiling capabilities/ that you might stall.

I seem to recall a Mexicana DC10 that stalled due to inattention in this mode...is that what you meant?

of course selecting mach hold/IAS hold can result in a climb that is protected against a stall, but the nose can ''hunt'' if there are airspeed vagueries.
This makes absolutely no sense in the case we are discussing. We were talking about "dangers" involved in utilising V/S mode to attain a 1000ft. step-climb in busy TMA's or during lower level climb-out.

I can only speak for the 737, but I fail to see how you would be able to put the aircraft into approach to stall while performing a 1000FPM step-climb with all automatics engaged without any malicious intend in the situations mentioned above.
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Old 13th Jan 2011, 21:39
  #98 (permalink)  
 
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d105



you fail to see...how about if an engine flamed out? or if the autothrottles were not working properly...

do you remember a 747 in altitude hold that lost one engine...slowed down, stalled, piece broke off, a safe landing at KSFO was accomplished...possibly went supersonic, possible spin

hey man, stuff happens
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Old 13th Jan 2011, 22:29
  #99 (permalink)  
 
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I saw that China Airlines 747 sitting at SFO for some time and wondered how the pilots could watch it happen without intervening. They must have been aware they lost an engine and needed a lower altitude.
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Old 14th Jan 2011, 00:51
  #100 (permalink)  
 
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Sevenstroke,

You are joking? You are seriously suggesting that after engaging the aircraft into a 1000fpm step-climb both pilots would not even notice an engine flaming out or the A/T not moving with reducing speed?

Seriously? Because in those cases it wouldn't even matter if it were the A/P or the actual pilots flying that particular aircraft. It was doomed from the start.

My question still stands thus.
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