A-320 autothrust complexity: a 'high-tech advance' or nerd arrogance
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Joined: Jul 2000
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From: Down south, USA.
A-320 autothrust complexity: a 'high-tech advance' or nerd arrogance
This question is totally sincere.
How do the hidden/subtle traps improve safety compared to the B-757/767 or even with the A-300/310?
Were the Airbus factory pilots given little input in this area, or were they simply worshiping at the "high-tech altar", allowing as much complexity as available with few thoughts given to how pilots think-that is, those who prefer logic. One example is a hand-flown go-around with no flight directors. One must select green dot speed or so, before the thrust "levers" are pulled back to the climb detent at clean-up altitude, i.e. 1500' agl. The brilliant machine will command idle power if not done correctly.
How do the hidden/subtle traps improve safety compared to the B-757/767 or even with the A-300/310?
Were the Airbus factory pilots given little input in this area, or were they simply worshiping at the "high-tech altar", allowing as much complexity as available with few thoughts given to how pilots think-that is, those who prefer logic. One example is a hand-flown go-around with no flight directors. One must select green dot speed or so, before the thrust "levers" are pulled back to the climb detent at clean-up altitude, i.e. 1500' agl. The brilliant machine will command idle power if not done correctly.
Joined: Jul 1999
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From: England
After years of flying aircraft with more conventional thrust systems, I have to say that the airbus system makes complete sense and becomes natural in no time at all.
Not saying it is better or worse than any other system just that it is very simple and easy to use.
Not saying it is better or worse than any other system just that it is very simple and easy to use.
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From: UK
One must select green dot speed or so, before the thrust "levers" are pulled back to the climb detent at clean-up altitude, i.e. 1500' agl. The brilliant machine will command idle power if not done correctly.
Also don't forget, a simple button press puts the levers completely back under your own control (which I think is wherer they should be when manually flying - but that's a totally personal preference).
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From: Correr es mi destino por no llevar papel
One must select green dot speed or so, before the thrust "levers" are pulled back to the climb detent at clean-up altitude, i.e. 1500' agl.
Now I´m curious too.
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From: hongkong
In most 'current spec' Airbii FBW a/c that I'm aware of, on selection of TOGA the FDs come back on and ATHR arms.
Now earlier software specs did have some subtle but important changes so I think it's important to find out just what spec a/c (or sim) you're talking about .
We had a situation in our fleet where an a/c that we had acquired from a previous operator (iso direct from AI) had a different response to TOGA application and sounds similar to what IO has described! It was an exciting ride for the crew (admittedly many moons ago now) when all the thrust came off!
With current spec a/c this has been resolved.
Now earlier software specs did have some subtle but important changes so I think it's important to find out just what spec a/c (or sim) you're talking about .
We had a situation in our fleet where an a/c that we had acquired from a previous operator (iso direct from AI) had a different response to TOGA application and sounds similar to what IO has described! It was an exciting ride for the crew (admittedly many moons ago now) when all the thrust came off!
With current spec a/c this has been resolved.
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The brilliant machine will command idle power if not done correctly
Thread Starter
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From: Down south, USA.
We are in Initial training (full-flight). But our Aircraft Operating Manuals are very well-written and both our training syllabus and the Instructor Pilots are the best around,in order that guys like me can have a good chance to get through ok 
.
The daily briefing study guides help condense much of the important information.
Was much of this system designed only to allow a small (weight) cost saving, or did the designers intentionally disregard test pilot input regarding normal pilot interface, assuming that it was present? From the studies of the factory pilots' A-320 airshow accident (no advance to TOGA detent) and the A-330 test flight, what a cruel irony, somehow.
The B-757 autothrottles were nothing like this, and I doubt that the system interrelationships on the B-737, F-100/28 and the Dornier 328 can compare to the various complexities, i.e. go-around at an intermediate altitude, with or without an autopilot and/or flight directors. I.e... Go momentarily from CLB to the TOGA detent, then back, but check also that the FMA says .........and a missed app. altitude is set on the FCU/FMA......This is not how pilots with traditional airmanship skills think, that is, those with 10-20 years flying real aircraft: DC-9s and 757s etc. Maybe airmanship skills were also disregarded during the A-320 design, allowing an extremely low level of experience to be substituted by technology (thereby never allowing additional, significant airmanship/flying skills to be acquired nor developed in this type of aircraft...never mind total "in the loop" awareness).
How do aircraft designers decide to incorporate unnecessary complexity and disregard the safety implications? Were weight savings the ONLY priority?
. The daily briefing study guides help condense much of the important information.
Was much of this system designed only to allow a small (weight) cost saving, or did the designers intentionally disregard test pilot input regarding normal pilot interface, assuming that it was present? From the studies of the factory pilots' A-320 airshow accident (no advance to TOGA detent) and the A-330 test flight, what a cruel irony, somehow.
The B-757 autothrottles were nothing like this, and I doubt that the system interrelationships on the B-737, F-100/28 and the Dornier 328 can compare to the various complexities, i.e. go-around at an intermediate altitude, with or without an autopilot and/or flight directors. I.e... Go momentarily from CLB to the TOGA detent, then back, but check also that the FMA says .........and a missed app. altitude is set on the FCU/FMA......This is not how pilots with traditional airmanship skills think, that is, those with 10-20 years flying real aircraft: DC-9s and 757s etc. Maybe airmanship skills were also disregarded during the A-320 design, allowing an extremely low level of experience to be substituted by technology (thereby never allowing additional, significant airmanship/flying skills to be acquired nor developed in this type of aircraft...never mind total "in the loop" awareness).
How do aircraft designers decide to incorporate unnecessary complexity and disregard the safety implications? Were weight savings the ONLY priority?
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From: England
Okay I have read the above post by Ignition Override at least 3 times and it makes absolutely no sense whatsoever.
As I said before, I find the Airbus system simple and intuitive and at no time does it vary with the rules of common sense or airmanship. It is not better or worse than any other system just slightly different.
I also believe that the auto thrust system, along with the joystick, provided a significant weight saving.
As I said before, I find the Airbus system simple and intuitive and at no time does it vary with the rules of common sense or airmanship. It is not better or worse than any other system just slightly different.
I also believe that the auto thrust system, along with the joystick, provided a significant weight saving.
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From: Earth
One must select green dot speed or so, before the thrust "levers" are pulled back to the climb detent at clean-up altitude, i.e. 1500' agl. The brilliant machine will command idle power if not done correctly.
At Go Around mode engagement, the target speed becomes Vapp or the current speed if higher. At acc alt, the target becomes green dot. No need to select it and I don't see how the thrust would go back to idle???
Joined: May 2001
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From: London,England
I've used it for years and years now and find it easy to use however I can't help feeling that Airbus "re-invented the wheel" just for sake of it and to be different from Boeing. I can't actually think of anything it does better than a standard system but I can think of several gotchas and complications that arise because of the design. IMHO it's one of the weakest parts of the a/c and they would have been better off putting a standard system in.
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The reversion is to the SPEED mode, power goes to idle because you have accelerated past the current selected speed, just pull the nose up for thrust. I agree with previous opinions in favour of the system, traps like TOGA LK, no FD go arounds, forgetting to arm the approach prior to managing the speed are easily dealt with.
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From: Correr es mi destino por no llevar papel
From the studies of the factory pilots' A-320 airshow accident (no advance to TOGA detent)
On the sim I´ve flown (if i´m free to use the expression) if you fly managed, your target becomes 250kt (adjustable through FMS) or green dot (if you fly selected). If you don´t like what your ATHR is doing - disconnect it as you pull it from TOGA to CLB. Ah yes, there´s airboos peciuliarity - ATHR is armed every time you make go-around so you have to press zee red bootons if you want to fly manually. Must be tough if you came from Böing.
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From: UK
Max Angle - unprecendented cockpit commonality (and by extension much simpler conversion training) across the A320/330/340 range was the long term plan when they designed that system, along with attempting to provide a more comfortable working environment, given the technical and managerial pressures on the modern pilot.
IO - I'm sure it'll get easier for you as you get further into the training. If you've gone from DC-9 to B757 I'm sure the FMS must have seemed like a strange box of tricks at first!
Either way you've got a job I'd love to do and I really hope it works out for you. The engineers who designed it were genuinely trying to make your life easier. That some people chose to present it as taking the pilot out of the loop was not the original intention of those who designed the system, and that I have from the horse's mouth.
IO - I'm sure it'll get easier for you as you get further into the training. If you've gone from DC-9 to B757 I'm sure the FMS must have seemed like a strange box of tricks at first!
Either way you've got a job I'd love to do and I really hope it works out for you. The engineers who designed it were genuinely trying to make your life easier. That some people chose to present it as taking the pilot out of the loop was not the original intention of those who designed the system, and that I have from the horse's mouth.
Joined: May 2001
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From: London,England
Well you can have commonality across types with any system as long as it's common to all of them, you don't need to design a new system to achieve it. I am an Airbus fan and really think it's a good machine but the interface with the autothrust system is not one of it's best features in my opinion.
