AF 447 report out
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RetiredF4;
As discussed earlier, the C* control law doesn't change at low speed, so the SS g rate command doesn't change to a pitch rate command.
The following quote from section 2.2.5 of the final report may be relevant to your questions regarding the change of gains with speed:
EDIT:: Another quote that may be helpful is from C. Favre's FBW - The Airbus Experience:
As discussed earlier, the C* control law doesn't change at low speed, so the SS g rate command doesn't change to a pitch rate command.
The following quote from section 2.2.5 of the final report may be relevant to your questions regarding the change of gains with speed:
In the specific case of alternate 2B law, some coefficients used in the longitudinal flight control law become speed-independent and are set for the maximum speed for the aeroplane configuration (330 kt in clean configuration). This hardly modifies the behaviour of the aeroplane in comparison to normal law, but can nevertheless induce an unusual response dynamic when the aeroplane has an abnormally low speed for the configuration.
A homogenous law, ensuring aircraft behaviour independent of the flight conditions and, in particular, independent of the centre of gravity location, is achieved by tabulating the gains as a function of the computed airspeed, high-lift configuration and centre of gravity location.
Last edited by HazelNuts39; 9th Aug 2012 at 13:14.
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Quote:
In the specific case of alternate 2B law, some coefficients used in the longitudinal flight control law become speed-independent and are set for the maximum speed for the aeroplane configuration (330 kt in clean configuration). This hardly modifies the behaviour of the aeroplane in comparison to normal law, but can nevertheless induce an unusual response dynamic when the aeroplane has an abnormally low speed for the configuration.
So when the THS started moving, NU, it was at this time that both PF and OTTO were commanding a flight path into STALL. For different reasons? Or were both trying to maintain "1G"?
Does that constitute the "Unusual Flight Response" ? BEA are saying the unusual response was that of the aircraft?
Is that what that sentence is saying about Alternate Law 2B?
Quote:
A homogenous law, ensuring aircraft behaviour independent of the flight conditions and, in particular, independent of the centre of gravity location, is achieved by tabulating the gains as a function of the computed airspeed, high-lift configuration and centre of gravity location.
Was 447 trying to "Land"? Did she confuse "high lift configuration" with 'high drag configuration'
In the specific case of alternate 2B law, some coefficients used in the longitudinal flight control law become speed-independent and are set for the maximum speed for the aeroplane configuration (330 kt in clean configuration). This hardly modifies the behaviour of the aeroplane in comparison to normal law, but can nevertheless induce an unusual response dynamic when the aeroplane has an abnormally low speed for the configuration.
So when the THS started moving, NU, it was at this time that both PF and OTTO were commanding a flight path into STALL. For different reasons? Or were both trying to maintain "1G"?
Does that constitute the "Unusual Flight Response" ? BEA are saying the unusual response was that of the aircraft?
Is that what that sentence is saying about Alternate Law 2B?
Quote:
A homogenous law, ensuring aircraft behaviour independent of the flight conditions and, in particular, independent of the centre of gravity location, is achieved by tabulating the gains as a function of the computed airspeed, high-lift configuration and centre of gravity location.
Was 447 trying to "Land"? Did she confuse "high lift configuration" with 'high drag configuration'
Last edited by Lyman; 9th Aug 2012 at 13:34.
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Originally Posted by Lyman
So when the THS started moving, NU, it was at this time that both PF and OTTO were commanding a flight path into STALL. For different reasons? Or were both trying to maintain "1G"?
As I read the quote from the final report, I would interpret 'unusual response dynamic' as 'sluggish', but I may be wrong.
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The THS doesn't move on its own, it is slaved to the elevator. The elevator moves in response to the PF's sidestick, whose 'demand' is interpreted by the flight control law. If there is no demand from the sidestick, the flight control law maintains essentially 1g. In short, the PF commanded the flight path into stall. OTTO disconnected at 02:10:05.
In the absence of PF input, NU, the a/c still trims for 1g. This means UP elevator.
With or without PF input, the a/c Stalls. Autopilot is not the issue? Neutral stick the a/c Stalls independently.....
You say, the elevator moves in response to the pilots input. It doesn't, it moves as a result of input by the computer. The computer commands NU, to provide 1G. The pilot provides a collateral input, NU. There is essentially a consonant, or "dual" input.
Because the THS is moving to follow elevators, who wants to parse who is who; they both are commanding the same thing, irrespective of the other's command.
All along, in this flight Law, this is what is happening, referenced to G.
No?
I think it is possible that the pilot was mimicking the flight path set by the computer, when he sensed less than 1G, he input NU. And he would be sensing less than 1G, whenever the a/c started to ND, both the pilot and computer have been adding up elevator. Now you could say he instigated the flight path that he ended up chasing up into the Stall, but he was terrified of descent, and "plus vitesse". Dropping airspeed was his goal, and climb was his result. Not cute, but he was in a corner......and his accomplice was the computer, for a different, and preprogrammed reason....
In the absence of PF input, NU, the a/c still trims for 1g. This means UP elevator.
With or without PF input, the a/c Stalls. Autopilot is not the issue? Neutral stick the a/c Stalls independently.....
You say, the elevator moves in response to the pilots input. It doesn't, it moves as a result of input by the computer. The computer commands NU, to provide 1G. The pilot provides a collateral input, NU. There is essentially a consonant, or "dual" input.
Because the THS is moving to follow elevators, who wants to parse who is who; they both are commanding the same thing, irrespective of the other's command.
All along, in this flight Law, this is what is happening, referenced to G.
No?
I think it is possible that the pilot was mimicking the flight path set by the computer, when he sensed less than 1G, he input NU. And he would be sensing less than 1G, whenever the a/c started to ND, both the pilot and computer have been adding up elevator. Now you could say he instigated the flight path that he ended up chasing up into the Stall, but he was terrified of descent, and "plus vitesse". Dropping airspeed was his goal, and climb was his result. Not cute, but he was in a corner......and his accomplice was the computer, for a different, and preprogrammed reason....
Last edited by Lyman; 9th Aug 2012 at 15:28.
HazelNuts39
As discussed earlier, the C* control law doesn't change at low speed, so the SS g rate command doesn't change to a pitch rate command.
As discussed earlier, the C* control law doesn't change at low speed, so the SS g rate command doesn't change to a pitch rate command.
The pitch command changes gradually from a pure g command in high speed to a pitch rate command in low speed. The changeover point being around 210 Kts. Meaning the SS orders a special amount of g change per amount of SS deflection above 210 kts and blends in pitch rate below that speed, SS ordering a amount of pitch change from existing pitch per amount of SS deflection. That does not change the Nz-law, without outside input the aircraft maintains 1 g flight in low and high speed and is therefore flightpath stable.
HazelNuts39
The THS doesn't move on its own, it is slaved to the elevator. The elevator moves in response to the PF's sidestick, whose 'demand' is interpreted by the flight control law. If there is no demand from the sidestick, the flight control law maintains essentially 1g.
The THS doesn't move on its own, it is slaved to the elevator. The elevator moves in response to the PF's sidestick, whose 'demand' is interpreted by the flight control law. If there is no demand from the sidestick, the flight control law maintains essentially 1g.
In short, the PF commanded the flight path into stall. OTTO disconnected at 02:10:05
Question remains though, would it have moved in the same timeframe without the help of NU SS input? Was elevator travel already maxed by the task to maintain 1 g without SS input or did the SS NU input aggravate the situation.
Therfore my question concerning the gains.
Last edited by RetiredF4; 9th Aug 2012 at 15:27.
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Indeed so... Neither the PF, nor the Flight Law, was paying any attention to the Stall Warning. There was no Alpha Prot, at this stage, so the computer is exonerated? PF was sure the SW was spurious, but he is not excused?
I suppose....I cannot disagree.....
quote...Franzl...
Question remains though, would it have moved in the same timeframe without the help of NU SS input? Was elevator travel already maxed by the task to maintain 1 g without SS input or did the SS NU input aggravate the situation.
I think yes, of course, the elevator has lost authority to climb further, so THS comes in, not to trim, but to command
It was 48 seconds after Stall that the Nose finally fell, thirty five degrees.
that is quite a potent control, that THS and elevator partnership..
Stall @ 2:10:57, Nose drops, 2:11:45....
I suppose....I cannot disagree.....
quote...Franzl...
Question remains though, would it have moved in the same timeframe without the help of NU SS input? Was elevator travel already maxed by the task to maintain 1 g without SS input or did the SS NU input aggravate the situation.
I think yes, of course, the elevator has lost authority to climb further, so THS comes in, not to trim, but to command
It was 48 seconds after Stall that the Nose finally fell, thirty five degrees.
that is quite a potent control, that THS and elevator partnership..
Stall @ 2:10:57, Nose drops, 2:11:45....
Last edited by Lyman; 9th Aug 2012 at 15:44.
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Lyman,
If the flightpath is one of decreasing airspeed, yes.
Unless the PF commands a downward change of flight path.
This is getting into semantics.
RetiredF4,
The response of the airplane changes. For example, in a steady state pull-up at 1.5 g, the pitch rate is 5.5 deg/sec at 100 kTAS, and 1.4 deg/sec at 400 kTAS.
It was 400 ft/s in the first application, but may vary as required in other applications. At the changeover speed the nz contribution to the feedback is equal to the pitch-rate contribution. Using that value in the above example, the pitchrate contribution would be 70% at 100kTAS, and 37% at 400 kTAS.
That is essentially correct except that, if the airspeed changes and the flight path is not level, maintaining 1g means that the flight path changes (slightly).
Agreed.
Probably yes, but much more slowly. At 2:10:49 the pitch attitude was 6 degrees and the rate of climb 1100 fpm. Without SS input that RoC would have been maintained until the airplane stalled.
In the absence of PF input, NU, the a/c still trims for 1g. This means UP elevator.
With or without PF input, the a/c Stalls.
You say, the elevator moves in response to the pilots input. It doesn't, it moves as a result of input by the computer. The computer commands NU, to provide 1G. The pilot provides a collateral input, NU. There is essentially a consonant, or "dual" input.
RetiredF4,
The pitch command changes gradually from a pure g command in high speed to a pitch rate command in low speed.
The changeover point being around 210 Kts.
That does noit change the Nz-law, without outside input the aircraft maintains 1 g flight and is therefore flightpath stable.
To maintain 1g flight ...
The timeframe (...) is after stall warning 2, when the THS trim started to move NU. And this movement would have happened also with SS neutral, as in NZ-Law the aircraft tries to maintain that 1 g (tries to maintain the flightpath.) Question remains though, would it have moved in the same timeframe without the help of NU SS input?
Last edited by HazelNuts39; 9th Aug 2012 at 16:28. Reason: forgot something
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I think we need to have a serious thought here about this 'progress' to software control. How many AB pilots would understand/anticipate EXACTLY what a movement or relaxation of the SS input would do in this situation? Is it reasonable to expect a stressed human to work this out, especially one that may well have been inculcated with the 'AB will look after you' mantra? Agreed, 'nose down' is the sensible thing to do, but..............have we actually reached the limit where a human can reasonably be expected to work out what is happening to what and how and why? Surely the cry for a drastic overhaul in both philosophy and content of FBW training needs to become very strident?
Now, Alt2B - let me see C* - is that 1g or flight path, or is it perhaps constant pitch attitude......? Do I have alpha protection in this mode or not? I cannot recall the groundschool - Oh! - what was that noise?
Now, Alt2B - let me see C* - is that 1g or flight path, or is it perhaps constant pitch attitude......? Do I have alpha protection in this mode or not? I cannot recall the groundschool - Oh! - what was that noise?
HazelNuts39
The response of the airplane changes. For example, in a steady state pull-up at 1.5 g, the pitch rate is 5.5 deg/sec at 100 kTAS, and 1.4 deg/sec at 400 kTAS.
The response of the airplane changes. For example, in a steady state pull-up at 1.5 g, the pitch rate is 5.5 deg/sec at 100 kTAS, and 1.4 deg/sec at 400 kTAS.
Are those values real? Can we compute the values for the speeds for the times when SS was held NU and when later on SS was ND for some seconds?
Would that tell us, that during the period of unreliable low speed the pitch rate was at the high end, thus SS input caused rapid pitch change?
And when speeds became valid again at the initial higher speeds the pitch rate would have been smaller?
Could you work those values into one of your marvelous graphs from the respective time period?
HazelNuts39
Probably yes, but much more slowly. At 2:10:49 the pitch attitude was 6 degrees and the rate of climb 1100 fpm. Without SS input that RoC would have been maintained until the airplane stalled.
Probably yes, but much more slowly. At 2:10:49 the pitch attitude was 6 degrees and the rate of climb 1100 fpm. Without SS input that RoC would have been maintained until the airplane stalled.
I see that point, but the normal acceleration (smoothed) was below 1g 13 seconds later and stayed below 1 g for over 1 minute. throughout the timeframe, the THS was moving. If the pull would have increased the travel rate, shouldnīt the normal acceleration then be above 1 g?
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Originally Posted by RetiredF4
the normal acceleration (smoothed) was below 1g 13 seconds later and stayed below 1 g for over 1 minute.
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BOAC
"- Oh! - what was that noise?"
BUFFET......
HN? Semantics? No, I think the computer was in control, regardless the Inputs of PF....
At the time of lost authority elevators, when the THS started to crank up again, the Stall was delayed, and for this reason, it can be said, that the actual Stall was caused not by the pilot, but by Autotrim...
Without Autotrim, the elevators can no longer keep the Nose UP, and thence, MUSH.... PF was ignoring trim, as he was taught to, he should not have. He was focused on overspeed, and he should not have...
He was flying G, on his lonesome, and he should not have, for the aircraft was duplicating his NU, degree by degree, and it should not have. Left alone, w/o THS, he experiences Nose Down on the natch, with more energy on hand, and less AoA. Does he recover the a/c? As yet, unknown. Or, does he eventually Stall, even without the THS.
I am going to say. No, for although at altitude, he is replicating a recovery from approach to STALL at low level, and with power, and reasonable AoA, he may mush along until he susses that he truly is not overspeed, and releases pressure on the stick, with engines blazing, until he recovers straight and level, without sink.
Can we say that the THS causes the aircraft to violate its type certificate?
IMO, Yes.....
"- Oh! - what was that noise?"
BUFFET......
HN? Semantics? No, I think the computer was in control, regardless the Inputs of PF....
At the time of lost authority elevators, when the THS started to crank up again, the Stall was delayed, and for this reason, it can be said, that the actual Stall was caused not by the pilot, but by Autotrim...
Without Autotrim, the elevators can no longer keep the Nose UP, and thence, MUSH.... PF was ignoring trim, as he was taught to, he should not have. He was focused on overspeed, and he should not have...
He was flying G, on his lonesome, and he should not have, for the aircraft was duplicating his NU, degree by degree, and it should not have. Left alone, w/o THS, he experiences Nose Down on the natch, with more energy on hand, and less AoA. Does he recover the a/c? As yet, unknown. Or, does he eventually Stall, even without the THS.
I am going to say. No, for although at altitude, he is replicating a recovery from approach to STALL at low level, and with power, and reasonable AoA, he may mush along until he susses that he truly is not overspeed, and releases pressure on the stick, with engines blazing, until he recovers straight and level, without sink.
Can we say that the THS causes the aircraft to violate its type certificate?
IMO, Yes.....
Last edited by Lyman; 9th Aug 2012 at 18:30.
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@ap08:
Graceful degradation based on maintaining familiarity. If you throw a pilot into a scenario where he or she will have to repeatedly perform an action that is not part of their day-to-day experience (such as manually trimming a FBW Airbus), then it adds a risk factor because they may not get it right. As such, Alternate Law exists when a partial systems failure means that Normal Law can no longer be sustained, but not all the benefits need be lost.
For a (very) rough analogy, when driving your car and the ABS system fails, you don't want it to take out the power steering and cruise control as well if the latter two systems are not showing any indications of failure.
Direct Law should only be reached in the air when the failures are significant enough that none of the FBW assistance can be relied on.
It's worth bearing in mind that despite all the in-depth discussion going on here, most FBW Airbus line pilots will never experience Alternate (or for that matter Direct Law in the air) outside of the simulator.
It doesn't matter what aircraft you fly - it's expected that a pilot should understand that pulling back to maintain 15 degrees pitch up when at cruise level is a very bad idea!
That's an oversimplified line propagated by the press - I'd be very surprised if conversion training didn't include the caveat "as long as everything is working - if not you need to take extra care".
I think that restricting an industry-wide review to FBW would be too narrow a focus. As PJ2 pointed out in Tech Log, the real problem is that from senior management on down, the peculiarities of the aviation industry is not well-understood anymore. In short, an MBA is not enough to run an airline safely.
Doesn't matter - the only mantra you need to remember is that outside of Normal Law, extra care must be taken.
Outside of Normal Law, no. Also not particularly difficult to remember.
Graceful degradation based on maintaining familiarity. If you throw a pilot into a scenario where he or she will have to repeatedly perform an action that is not part of their day-to-day experience (such as manually trimming a FBW Airbus), then it adds a risk factor because they may not get it right. As such, Alternate Law exists when a partial systems failure means that Normal Law can no longer be sustained, but not all the benefits need be lost.
For a (very) rough analogy, when driving your car and the ABS system fails, you don't want it to take out the power steering and cruise control as well if the latter two systems are not showing any indications of failure.
Direct Law should only be reached in the air when the failures are significant enough that none of the FBW assistance can be relied on.
It's worth bearing in mind that despite all the in-depth discussion going on here, most FBW Airbus line pilots will never experience Alternate (or for that matter Direct Law in the air) outside of the simulator.
Is it reasonable to expect a stressed human to work this out, especially one that may well have been inculcated with the 'AB will look after you' mantra?
Surely the cry for a drastic overhaul in both philosophy and content of FBW training needs to become very strident?
Now, Alt2B - let me see C* - is that 1g or flight path, or is it perhaps constant pitch attitude......?
Do I have alpha protection in this mode or not?
Last edited by DozyWannabe; 9th Aug 2012 at 21:02.
DozyWannabe
If you throw a pilot into a scenario where he or she will have to repeatedly perform an action that is not part of their day-to-day experience (such as manually trimming a FBW Airbus), then it adds a risk factor because they may not get it right. As such, Alternate Law exists when a partial systems failure means that Normal Law can no longer be sustained, but not all the benefits need be lost.
If you throw a pilot into a scenario where he or she will have to repeatedly perform an action that is not part of their day-to-day experience (such as manually trimming a FBW Airbus), then it adds a risk factor because they may not get it right. As such, Alternate Law exists when a partial systems failure means that Normal Law can no longer be sustained, but not all the benefits need be lost.
Guess what i myself and some pilots of old school would prefer more.
DozyWannabe
Doesn't matter - the only mantra you need to remember is that outside of Normal Law, extra care must be taken.
Doesn't matter - the only mantra you need to remember is that outside of Normal Law, extra care must be taken.
Last edited by RetiredF4; 9th Aug 2012 at 21:17.
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Wouldn't you say it's a fairly minor issue compared to pulling 15 degrees nose-up when you're already at your cruise level?
So is detection and recovery from stall, which they didn't manage.
The extra care can be boiled down to a single rule - stay within the flight envelope outside of Normal Law!
It's an opinion you're welcome to, but to me it seems like an attempt to pin blame on an aspect of the design because of a pre-determined conclusion that you don't like the design.
Most of the in-depth knowledge was held by the Flight Engineer in the old days. I suspect that were you to show an old FE the layout of the Airbus systems they'd consider it child's play compared to what they had to deal with.
Not at all - what bothers me is that those harping on about the level of complexity either haven't flown the FBW Airbus, or have flown it despite having a pre-existing dislike of the design. There appear to me to be just as many current and former FBW Airbus pilots who don't find the design overly complex at all. They don't post as frequently, but they're definitely around.
And while a risk of not being able to trim manually may be present , which is teached in basic aircrew training ab initio
they had to deal with an autotrimming function not limitied by protections as it is present in the day to day AB flying.
It at least should be known, what kind of extra care must be taken. To know that, it is mandatory to recognize the system limitations asociated with the special circumstances.
It at least should be known, what kind of extra care must be taken. To know that, it is mandatory to recognize the system limitations asociated with the special circumstances.
Guess what i myself and some pilots of old school would prefer more.
As we (as retired or non AB flyers on this thread) can recognize here and as my own feedback with active AB-pilots shows, the knowledge about downgraded systems is way of the scale we oldheads had been checked about.
That may be a management failure or AB philosophy. Your statement shows, that you are either ignorant or not sensible enough to the same theme here.
Originally Posted by RetiredF4
the normal acceleration (smoothed) was below 1g 13 seconds later and stayed below 1 g for over 1 minute.
Answer HazelNuts39
13 seconds later, at 2:11:02, the airplane was stalled, beyond maximum lift, unable to provide the LF demanded by the sidestick, hence elevator and THS continued to move NU, attempting in vain to accommodate the SS demand.
the normal acceleration (smoothed) was below 1g 13 seconds later and stayed below 1 g for over 1 minute.
Answer HazelNuts39
13 seconds later, at 2:11:02, the airplane was stalled, beyond maximum lift, unable to provide the LF demanded by the sidestick, hence elevator and THS continued to move NU, attempting in vain to accommodate the SS demand.
Even a 1 g demand with SS neutral would have stimulated the automation to order an NU demand to the elevators and the THS.
What difference does it make, if a SS NU command in whatever magnitude is made under circumstances, when the the overall outcome of this command is less than 1 g concerning the elevator and THS movement? SS neutral would have forced the identical elevator and THS NU order from the automation to achieve and maintain the "SS neutral 1 g command". This 1 g could not be achieved in the relevant aerodynamic and energy available environment, neither with SS NU command nor without NU SS command.
So what did the SS NU command change bottom line? It only shows, that the PF and the PNF didnīt grasp the correct situation and therefore made the wrong SS input. But this input didnt worsen the situation imho.
Only ND input would have had any positive effect, as we know in hindsight and some of us may have known from the beginning.
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If you throw a pilot into a scenario where he or she will have to repeatedly perform an action that is not part of their day-to-day experience (such as manually trimming a FBW Airbus), then it adds a risk factor because they may not get it right.
AF447 is a real-life example of a situation when Alternate law did not save the day, and possibly even contributed to the events that led to the crash. Are there real-life examples of the contrary: situations when the plane suffered malfunctions and reverted to the alternate law, and in that condition successfully brought back to a runway in one piece?
EDIT: never mind this post, I now realize that the same situation happened each time there was unreliable airspeed.
Last edited by ap08; 9th Aug 2012 at 21:55.
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"Only ND input would have had any positive effect, as we know in hindsight and some of us may have known from the beginning."
Are we sure that it required actual input or was the airframe paid out with elevator only, and that the Nose would come down on her own without the renewed action of THS movement? She had energy, had not succumbed to partial ballistic flight (momentum only....BEA).
Earlier on, how did she get to +1.65 G, whilst in load factor 1G?
Are we sure that it required actual input or was the airframe paid out with elevator only, and that the Nose would come down on her own without the renewed action of THS movement? She had energy, had not succumbed to partial ballistic flight (momentum only....BEA).
Earlier on, how did she get to +1.65 G, whilst in load factor 1G?
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In reference to system behaviour only (to avoid argument), the sim experience indicated that it took 6-8 seconds to roll the THS back to neutral with full forward stick applied, and with full forward stick the trim wheel very rapidly responded to the command (at most 1 second or two).
Judging by the DFDR traces even with full-NU THS, the nose did drop when it became slow enough - the problem was because of the THS and elevator position, it came straight back up again as soon as there was enough speed to do so. I don't buy the idea of autotrim in isolation making a recovery harder, because it was only doing what was asked of it. With the correct inputs it would have been a significant help.
Earlier on, how did she get to +1.65 G, whilst in load factor 1G?
Last edited by DozyWannabe; 9th Aug 2012 at 22:23.
DozyWannabe
Wouldn't you say it's a fairly minor issue compared to pulling 15 degrees nose-up when you're already at your cruise level?
Wouldn't you say it's a fairly minor issue compared to pulling 15 degrees nose-up when you're already at your cruise level?
DozyWannabe
So is detection and recovery from stall, which they didn't manage.
So is detection and recovery from stall, which they didn't manage.
DozyWannabe
The extra care can be boiled down to a single rule - stay within the flight envelope outside of Normal Law!
The extra care can be boiled down to a single rule - stay within the flight envelope outside of Normal Law!
DozyWannabe
It's an opinion you're welcome to, but to me it seems like an attempt to pin blame on an aspect of the design because of a pre-determined conclusion that you don't like the design.
It's an opinion you're welcome to, but to me it seems like an attempt to pin blame on an aspect of the design because of a pre-determined conclusion that you don't like the design.
DozyWannabe
Most of the in-depth knowledge was held by the Flight Engineer in the old days. I suspect that were you to show an old FE the layout of the Airbus systems they'd consider it child's play compared to what they had to deal with.
Most of the in-depth knowledge was held by the Flight Engineer in the old days. I suspect that were you to show an old FE the layout of the Airbus systems they'd consider it child's play compared to what they had to deal with.
DozyWannabe
Not at all - what bothers me is that those harping on about the level of complexity either haven't flown the FBW Airbus, or have flown it despite having a pre-existing dislike of the design. There appear to me to be just as many current and former FBW Airbus pilots who don't find the design overly complex at all. They don't post as frequently, but they're definitely around.
Not at all - what bothers me is that those harping on about the level of complexity either haven't flown the FBW Airbus, or have flown it despite having a pre-existing dislike of the design. There appear to me to be just as many current and former FBW Airbus pilots who don't find the design overly complex at all. They don't post as frequently, but they're definitely around.
Last edited by RetiredF4; 9th Aug 2012 at 22:34.