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QF72 story - wow

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  QF72 story - wow Clifford Heath <clifford.heath@gmail.com> - 2017-05-14 22:03 +1000
    Re: QF72 story - wow BM2335 <BM265@DMM.com.au> - 2017-05-15 12:25 +0800
    Re: QF72 story - wow Dimiter_Popoff <dp@tgi-sci.com> - 2017-05-15 16:05 +0300
      Re: QF72 story - wow Reinhardt Behm <rbehm@hushmail.com> - 2017-05-15 21:58 +0800
        Re: QF72 story - wow David Brown <david.brown@hesbynett.no> - 2017-05-15 16:48 +0200
          Re: QF72 story - wow Reinhardt Behm <rbehm@hushmail.com> - 2017-05-15 23:34 +0800
            Re: QF72 story - wow Tom Gardner <spamjunk@blueyonder.co.uk> - 2017-05-15 18:00 +0100
            Re: QF72 story - wow Robert Wessel <robertwessel2@yahoo.com> - 2017-05-15 17:49 -0500
            Re: QF72 story - wow David Brown <david.brown@hesbynett.no> - 2017-05-16 09:06 +0200
              Re: QF72 story - wow upsidedown@downunder.com - 2017-05-16 19:46 +0300
            Re: QF72 story - wow rickman <gnuarm@gmail.com> - 2017-05-16 10:41 -0400
              Re: QF72 story - wow Reinhardt Behm <rbehm@hushmail.com> - 2017-05-17 23:13 +0800
                Re: QF72 story - wow rickman <gnuarm@gmail.com> - 2017-05-17 11:54 -0400
                  Re: QF72 story - wow Dimiter_Popoff <dp@tgi-sci.com> - 2017-05-17 21:43 +0300
                    Re: QF72 story - wow rickman <gnuarm@gmail.com> - 2017-05-17 16:03 -0400
                      Re: QF72 story - wow Dimiter_Popoff <dp@tgi-sci.com> - 2017-05-18 00:27 +0300
                        Re: QF72 story - wow rickman <gnuarm@gmail.com> - 2017-05-17 19:56 -0400
            Re: QF72 story - wow upsidedown@downunder.com - 2017-05-16 19:30 +0300
              Re: QF72 story - wow Robert Wessel <robertwessel2@yahoo.com> - 2017-05-16 23:05 -0500
              Re: QF72 story - wow Reinhardt Behm <rbehm@hushmail.com> - 2017-05-17 23:05 +0800
          Re: QF72 story - wow rickman <gnuarm@gmail.com> - 2017-05-16 10:25 -0400
        Re: QF72 story - wow Przemek Klosowski <przemek@tux.dot.org> - 2017-05-18 12:45 +0000
      Re: QF72 story - wow upsidedown@downunder.com - 2017-05-16 19:10 +0300
        Re: QF72 story - wow Dimiter_Popoff <dp@tgi-sci.com> - 2017-05-16 19:48 +0300
        Re: QF72 story - wow lasselangwadtchristensen@gmail.com - 2017-05-19 17:40 -0700
    Re: QF72 story - wow Tim Wescott <seemywebsite@myfooter.really> - 2017-05-15 12:34 -0500
      Re: QF72 story - wow Robert Wessel <robertwessel2@yahoo.com> - 2017-05-15 17:21 -0500
      Re: QF72 story - wow rickman <gnuarm@gmail.com> - 2017-05-16 10:47 -0400
        Re: QF72 story - wow Jan Coombs <jenfhaomndgfwutc@murmic.plus.com> - 2017-05-17 10:31 +0100
          Re: QF72 story - wow Reinhardt Behm <rbehm@hushmail.com> - 2017-05-17 22:20 +0800
            Re: QF72 story - wow rickman <gnuarm@gmail.com> - 2017-05-17 10:36 -0400
    Re: QF72 story - wow George Neuner <gneuner2@comcast.net> - 2017-05-15 17:28 -0400
      Re: QF72 story - wow Robert Wessel <robertwessel2@yahoo.com> - 2017-05-15 17:22 -0500
      Re: QF72 story - wow Dimiter_Popoff <dp@tgi-sci.com> - 2017-05-16 10:51 +0300
        Re: QF72 story - wow Clifford Heath <clifford.heath@gmail.com> - 2017-05-16 18:01 +1000
    Re: QF72 story - wow upsidedown@downunder.com - 2017-05-16 18:54 +0300
      Re: QF72 story - wow Robert Wessel <robertwessel2@yahoo.com> - 2017-05-16 23:23 -0500

Page 2 of 2 — ← Prev page 1 [2]

#26529

On 5/15/2017 10:48 AM, David Brown wrote:
> On 15/05/17 15:58, Reinhardt Behm wrote:
>> AT Monday 15 May 2017 21:05, Dimiter_Popoff wrote:
>>
>>> On 14.5.2017 г. 15:03, Clifford Heath wrote:
>>>> This story is a doozy.
>>>> <http://www.smh.com.au/good-weekend/the-untold-story-of-qf72-what-
>> happens-when-psycho-automation-leaves-pilots-powerless-20170510-gw26ae.html>
>>>>
>>>
>>> Interesting reading, I read almost the whole article. If I start
>>> commenting on the quality of the software they mut have on these planes
>>> I'll go into a rant predictable to all seasoned group members so
>>> I won't.
>>>
>>> But I am amazed that - as the article states - the board computer
>>> on these planes has priority over the pilots. This is not a bug, it
>>> is an error at the product concept level... If it is true of course,
>>> I still have difficulties believing that. The fact they did manage
>>> to gain some manual control hints towards "not quite true".
>>
>> I am doing airborne software myself.
>> You are correct. It is not a bug, it is a serious error of the requirements.
>> Software has to be written according to requirements and this is verified
>> (DO-178). If the sys-reqs are erroneous the software is also incorrect.
>>
>
> What about that case of a plane crash because the pilot intentionally
> crashed it (as far as they could figure out afterwards, anyway)?  He was
> mentally unstable and drove the plane into a mountain.  If the onboard
> computers had had priority over the pilot in that case, there would have
> been no crash.
>
> It is far from easy to say who or what is most reliable in cases like
> this, and who or what should have priority.  Automated systems can (if
> designed properly) be safer and more stable than humans - but on the
> other hand, humans are better at handling unexpected situations.
>
> However, I thought that critical flight systems were made in triplicate,
> and if one goes bananas it gets outvoted, and the other two run the
> plane?  Did that not happen here?

Didn't anyone pay attention?  There were a total of 10 errors that 
happened to cause the misreporting of the angle of the airplane.  These 
errors were not reported to the pilots.  This was the failure of the 
system, not the fact that the plane overrode the pilot's commands.

The statistics don't lie.  Most accidents are caused by pilot errors, 
not plane malfunctions.  That is why the plane can override the pilot. 
Humans are almost always the weak link in the system.

In this case the errors should have been reported to the pilots so they 
could take action to prevent the misreporting of critical flight 
information.  The malfunctioning systems could have been shut down, not 
unlike HAL in 2001, but without the drama.

-- 

Rick C

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#26617

On Mon, 15 May 2017 21:58:19 +0800, Reinhardt Behm wrote:

> Similar to the crash of an Airbus in Warsaw. In that case it was an
> interlock that prevented the thrust reversal when not both wheels see
> weight-on-wheel. The landing happened with extreme side wind keeping one
> side slightly lifted. Thus thrust reversal was blocked and the plane ran
> past the runway and crashed into the ground, killing most passengers.

Thankfully, only one passengers and one crew member died: most survived.
https://en.wikipedia.org/wiki/Lufthansa_Flight_2904

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#26533

On Mon, 15 May 2017 16:05:11 +0300, Dimiter_Popoff <dp@tgi-sci.com>
wrote:

>On 14.5.2017 ?. 15:03, Clifford Heath wrote:
>> This story is a doozy.
>> <http://www.smh.com.au/good-weekend/the-untold-story-of-qf72-what-happens-when-psycho-automation-leaves-pilots-powerless-20170510-gw26ae.html>
>>
>
>Interesting reading, I read almost the whole article. If I start
>commenting on the quality of the software they mut have on these planes
>I'll go into a rant predictable to all seasoned group members so
>I won't.
>
>But I am amazed that - as the article states - the board computer
>on these planes has priority over the pilots. This is not a bug, it
>is an error at the product concept level... If it is true of course,
>I still have difficulties believing that. The fact they did manage
>to gain some manual control hints towards "not quite true".

Look at the AF286 crash at Mulhouse when after a low fly-by the plane
dropped into the trees at the hill at the end of the runway. The
automation prevented a pilot too high nose up attitude, which would
have caused a stall to the ground, causing a lot of fatalities. In
this case, the pane dropped below the tree line softly with a small
number of fatalities.
 

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#26536

On 16.5.2017 г. 19:10, upsidedown@downunder.com wrote:
> On Mon, 15 May 2017 16:05:11 +0300, Dimiter_Popoff <dp@tgi-sci.com>
> wrote:
>
>> On 14.5.2017 ?. 15:03, Clifford Heath wrote:
>>> This story is a doozy.
>>> <http://www.smh.com.au/good-weekend/the-untold-story-of-qf72-what-happens-when-psycho-automation-leaves-pilots-powerless-20170510-gw26ae.html>
>>>
>>
>> Interesting reading, I read almost the whole article. If I start
>> commenting on the quality of the software they mut have on these planes
>> I'll go into a rant predictable to all seasoned group members so
>> I won't.
>>
>> But I am amazed that - as the article states - the board computer
>> on these planes has priority over the pilots. This is not a bug, it
>> is an error at the product concept level... If it is true of course,
>> I still have difficulties believing that. The fact they did manage
>> to gain some manual control hints towards "not quite true".
>
> Look at the AF286 crash at Mulhouse when after a low fly-by the plane
> dropped into the trees at the hill at the end of the runway. The
> automation prevented a pilot too high nose up attitude, which would
> have caused a stall to the ground, causing a lot of fatalities. In
> this case, the pane dropped below the tree line softly with a small
> number of fatalities.
>

Don't get me wrong, I am anything but against automation. In the
situation you describe limiting the impact of the pilot commands
can be compared with say current limiting of the output of a power
supply, nothing wrong limiting it such that it won't get fried
because one turned a knob too much or something. Then all the
large airplane controls nowadays I imagine are with servos etc.,
nobody in his right mind would allow pilot access to the
firmware of these things which say controls the PWM of the
servos.
But above a certain level the pilot should be able to disable
some autopilot thing which causes nosedives because it went
bananas.
BTW there is a nice short story from about 50 years ago by Lem,
"Ananke", built on that kind of stuff (just a nice reading so
I am mentioning it for those who are lucky to not have read
it and can enjoy it now, one of his best IMO).

Dimiter

------------------------------------------------------
Dimiter Popoff, TGI             http://www.tgi-sci.com
------------------------------------------------------
http://www.flickr.com/photos/didi_tgi/

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#26631

Den tirsdag den 16. maj 2017 kl. 18.10.24 UTC+2 skrev upsid...@downunder.com:
> On Mon, 15 May 2017 16:05:11 +0300, Dimiter_Popoff <dp@tgi-sci.com>
> wrote:
> 
> >On 14.5.2017 ?. 15:03, Clifford Heath wrote:
> >> This story is a doozy.
> >> <http://www.smh.com.au/good-weekend/the-untold-story-of-qf72-what-happens-when-psycho-automation-leaves-pilots-powerless-20170510-gw26ae.html>
> >>
> >
> >Interesting reading, I read almost the whole article. If I start
> >commenting on the quality of the software they mut have on these planes
> >I'll go into a rant predictable to all seasoned group members so
> >I won't.
> >
> >But I am amazed that - as the article states - the board computer
> >on these planes has priority over the pilots. This is not a bug, it
> >is an error at the product concept level... If it is true of course,
> >I still have difficulties believing that. The fact they did manage
> >to gain some manual control hints towards "not quite true".
> 
> Look at the AF286 crash at Mulhouse when after a low fly-by the plane
> dropped into the trees at the hill at the end of the runway. The
> automation prevented a pilot too high nose up attitude, which would
> have caused a stall to the ground, causing a lot of fatalities. In
> this case, the pane dropped below the tree line softly with a small
> number of fatalities.

I assume you mean AF296, and afaiu there was and still is quite some controversy
as to what actually happened

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#26521

On Sun, 14 May 2017 22:03:19 +1000, Clifford Heath wrote:

> This story is a doozy.
> <http://www.smh.com.au/good-weekend/the-untold-story-of-qf72-what-
happens-when-psycho-automation-leaves-pilots-powerless-20170510-
gw26ae.html>

Airbus has always had a policy of believing that engineers can program a 
blind computer to fly a plane better than a pilot with eyeballs.  In 
addition to this event, it's resulted in planes flying into mountainsides 
with wings that simply were not stressed with any excessive G-forces from 
the requested pullup.

I have friends who are Boeing engineers.  Boeing's policy is that if 
you're going to have a human pilot in the hot seat, you should trust him 
when the chips are down.  This makes for more impressive crashes when 
less than well-trained pilots are flying the planes, but fewer crashes 
when you've got good piloting.

-- 

Tim Wescott
Wescott Design Services
http://www.wescottdesign.com

I'm looking for work -- see my website!

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#26523

On Mon, 15 May 2017 12:34:14 -0500, Tim Wescott
<seemywebsite@myfooter.really> wrote:

>On Sun, 14 May 2017 22:03:19 +1000, Clifford Heath wrote:
>
>> This story is a doozy.
>> <http://www.smh.com.au/good-weekend/the-untold-story-of-qf72-what-
>happens-when-psycho-automation-leaves-pilots-powerless-20170510-
>gw26ae.html>
>
>Airbus has always had a policy of believing that engineers can program a 
>blind computer to fly a plane better than a pilot with eyeballs.  In 
>addition to this event, it's resulted in planes flying into mountainsides 
>with wings that simply were not stressed with any excessive G-forces from 
>the requested pullup.


That's the hypothetical that's always trotted out; AFAIK, it's not
actually happened.  And flying into a mountainside in a modern, EGPWS
equipped, airliner, would require immense levels of concentration to
tune out the blaring alarm.  Of course the guys who ran an early
Sukhoi SSJ 100 into Mt. Salak a few years ago demonstrated humans can
do just that ("We're in clouds and the computer says there are
mountains?  Must be a database problem!").


>I have friends who are Boeing engineers.  Boeing's policy is that if 
>you're going to have a human pilot in the hot seat, you should trust him 
>when the chips are down.  This makes for more impressive crashes when 
>less than well-trained pilots are flying the planes, but fewer crashes 
>when you've got good piloting.


OTOH, studies (in sims) have show that Airbus pilots pull higher G's
in extreme avoidance maneuvers than pilots of aircraft without hard
envelope protections.  For the simple reason that they don't worry
about the "edge", and can just haul back on the stick and get very
near the maximum possible performance.

In any event, it's a non-issue.  The actual difference in available
maneuver load is actually fairly small, and most of the time if you're
so far gone that you need to pull enough G's to bend the airframe,
it's probably because you screwed up severely multiple times already.

And there are darn few crashes of modern airliners.  And almost all of
the ones that do occur are fairly unique.

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#26531

On 5/15/2017 1:34 PM, Tim Wescott wrote:
> On Sun, 14 May 2017 22:03:19 +1000, Clifford Heath wrote:
>
>> This story is a doozy.
>> <http://www.smh.com.au/good-weekend/the-untold-story-of-qf72-what-
> happens-when-psycho-automation-leaves-pilots-powerless-20170510-
> gw26ae.html>
>
> Airbus has always had a policy of believing that engineers can program a
> blind computer to fly a plane better than a pilot with eyeballs.

Which is true!  Pilot error is the single biggest cause of fatalities in 
plane accidents.


> In
> addition to this event, it's resulted in planes flying into mountainsides
> with wings that simply were not stressed with any excessive G-forces from
> the requested pullup.
>
> I have friends who are Boeing engineers.  Boeing's policy is that if
> you're going to have a human pilot in the hot seat, you should trust him
> when the chips are down.  This makes for more impressive crashes when
> less than well-trained pilots are flying the planes, but fewer crashes
> when you've got good piloting.

How do you decide when the chips are down?  I'd like to see the 
statistics you are quoting.

-- 

Rick C

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#26568

On Tue, 16 May 2017 10:47:14 -0400
rickman <gnuarm@gmail.com> wrote:

> Which is true!  Pilot error is the single biggest cause of
> fatalities in plane accidents.

If the actual causes were 50/50, but some pilots died, I
suspect that lack of evidence would bias the results. 

Jan Coombs

> 
> How do you decide when the chips are down?  I'd like to see
> the statistics you are quoting.
> 
> -- 
> 
> Rick C

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#26577

AT Wednesday 17 May 2017 17:31, Jan Coombs wrote:

> On Tue, 16 May 2017 10:47:14 -0400
> rickman <gnuarm@gmail.com> wrote:
> 
>> Which is true!  Pilot error is the single biggest cause of
>> fatalities in plane accidents.
> 
> If the actual causes were 50/50, but some pilots died,

That helps natural selection.

-- 
Reinhardt

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#26578

On 5/17/2017 10:20 AM, Reinhardt Behm wrote:
> AT Wednesday 17 May 2017 17:31, Jan Coombs wrote:
>
>> On Tue, 16 May 2017 10:47:14 -0400
>> rickman <gnuarm@gmail.com> wrote:
>>
>>> Which is true!  Pilot error is the single biggest cause of
>>> fatalities in plane accidents.
>>
>> If the actual causes were 50/50, but some pilots died,
>
> That helps natural selection.

Yes, it helps to eliminate the homo sapiens who think man can fly!

-- 

Rick C

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#26522

On Sun, 14 May 2017 22:03:19 +1000, Clifford Heath
<clifford.heath@gmail.com> wrote:

>This story is a doozy.
><http://www.smh.com.au/good-weekend/the-untold-story-of-qf72-what-happens-when-psycho-automation-leaves-pilots-powerless-20170510-gw26ae.html>


Instead of a newspaper, why not read the accident report?

https://www.atsb.gov.au/publications/investigation_reports/2008/aair/ao-2008-070.aspx

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#26524

On Mon, 15 May 2017 17:28:36 -0400, George Neuner
<gneuner2@comcast.net> wrote:

>On Sun, 14 May 2017 22:03:19 +1000, Clifford Heath
><clifford.heath@gmail.com> wrote:
>
>>This story is a doozy.
>><http://www.smh.com.au/good-weekend/the-untold-story-of-qf72-what-happens-when-psycho-automation-leaves-pilots-powerless-20170510-gw26ae.html>
>
>
>Instead of a newspaper, why not read the accident report?
>
>https://www.atsb.gov.au/publications/investigation_reports/2008/aair/ao-2008-070.aspx


You beat me to it.  Unlike the breathless article, it actually has
useful, and factual, information.  It's not that hard a read, either.

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#26527

On 16.5.2017 г. 00:28, George Neuner wrote:
> On Sun, 14 May 2017 22:03:19 +1000, Clifford Heath
> <clifford.heath@gmail.com> wrote:
>
>> This story is a doozy.
>> <http://www.smh.com.au/good-weekend/the-untold-story-of-qf72-what-happens-when-psycho-automation-leaves-pilots-powerless-20170510-gw26ae.html>
>
>
> Instead of a newspaper, why not read the accident report?
>
> https://www.atsb.gov.au/publications/investigation_reports/2008/aair/ao-2008-070.aspx
>

Hmmmm, sounds a little like a whitewash. "Happened just once" in so many
millions flight hours etc. - we all here know what this means.
This clearly is a programming error - and not one which is to be caught
by testing, rather the programmer must be good enough to not allow it
happen by design, during planning.

On the "automata are better than humans" from other posts - if they are
better and humans cannot override them why are there any humans at all
in the cockpit? I know if I were to fly something I would want to be
in control when I want to be, although of course I would make use of
all utilities available as long as they work OK.

Dimiter

------------------------------------------------------
Dimiter Popoff, TGI             http://www.tgi-sci.com
------------------------------------------------------
http://www.flickr.com/photos/didi_tgi/

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#26528

On 16/05/17 17:51, Dimiter_Popoff wrote:
> On 16.5.2017 г. 00:28, George Neuner wrote:
>> On Sun, 14 May 2017 22:03:19 +1000, Clifford Heath
>> <clifford.heath@gmail.com> wrote:
>>
>>> This story is a doozy.
>>> <http://www.smh.com.au/good-weekend/the-untold-story-of-qf72-what-happens-when-psycho-automation-leaves-pilots-powerless-20170510-gw26ae.html>
>>>
>>
>>
>> Instead of a newspaper, why not read the accident report?
>> https://www.atsb.gov.au/publications/investigation_reports/2008/aair/ao-2008-070.aspx

Thanks,  that was interesting.

> Hmmmm, sounds a little like a whitewash. "Happened just once" in so many
> millions flight hours etc. - we all here know what this means.
> This clearly is a programming error - and not one which is to be caught
> by testing, rather the programmer must be good enough to not allow it
> happen by design, during planning.
>
> On the "automata are better than humans" from other posts - if they are
> better and humans cannot override them why are there any humans at all
> in the cockpit? I know if I were to fly something I would want to be
> in control when I want to be, although of course I would make use of
> all utilities available as long as they work OK.

The accident report suggests that the sensor computer attributed the
right value to the wrong sensor. That seems very likely to not be a
cosmic ray strike... but it could be a static pointer to a data
structure that isn't meant to change, and one bit got flipped.
Such things shouldn't happen in this class of software, of course.

Clifford Heath

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#26532

On Sun, 14 May 2017 22:03:19 +1000, Clifford Heath
<clifford.heath@gmail.com> wrote:

>This story is a doozy.
><http://www.smh.com.au/good-weekend/the-untold-story-of-qf72-what-happens-when-psycho-automation-leaves-pilots-powerless-20170510-gw26ae.html>

A much better factual description can be found in Aviation Herald
http://www.avherald.com/h?article=40de5374/0006&opt=0

Regarding the referenced Air France 447 crash into the Atlantic, which
was nat caused by automation but by inexperienced co-pilots (captain
was sleeping) who manually stalled the plane from 10 km to the sea due
to frozen pitot tubes (and hence no reliable speed info).

As a general observation, one should not rely on a single method of
redundancy. Using multiple sensors of the same type doesn't always
help. This was clearly shown in Fukushima, were all diesel emergency
power generators got wet due to the tsunami.
 

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#26560

On Tue, 16 May 2017 18:54:15 +0300, upsidedown@downunder.com wrote:

>On Sun, 14 May 2017 22:03:19 +1000, Clifford Heath
><clifford.heath@gmail.com> wrote:
>
>>This story is a doozy.
>><http://www.smh.com.au/good-weekend/the-untold-story-of-qf72-what-happens-when-psycho-automation-leaves-pilots-powerless-20170510-gw26ae.html>
>
>A much better factual description can be found in Aviation Herald
>http://www.avherald.com/h?article=40de5374/0006&opt=0
>
>Regarding the referenced Air France 447 crash into the Atlantic, which
>was nat caused by automation but by inexperienced co-pilots (captain
>was sleeping) who manually stalled the plane from 10 km to the sea due
>to frozen pitot tubes (and hence no reliable speed info).
>
>As a general observation, one should not rely on a single method of
>redundancy. Using multiple sensors of the same type doesn't always
>help. This was clearly shown in Fukushima, were all diesel emergency
>power generators got wet due to the tsunami.


Unfortunately no one has invented anything better than a pitot* as an
air speed probe yet.  There are a few alternatives**, but all have
major issues (they have a lot more modes where they don't return valid
data), and at least some of them are likely to be worse in the
presence of icing.

I've thought that something like a doppler radar reading the true
relative motion of air molecules some distance ahead of the aircraft
(enough to be thoroughly out of the flow field distortions caused by
the aircraft), would be a really nice backup to the conventional air
flow sensors, but unless you can assume the presence of considerable
moisture (and you can't) such things are very delicate and
cantankerous beasts - hardly what you'd want as a primary input to
your flight control systems).


*They are fundamentally very simple, and work very well within their
design range.  They are susceptible to icing (hence most of the one
ones intended for aircraft that might fly in such conditions have big
heaters attached to them), and errors due to the air flow being too
far off center.  They also have issue with transonic and supersonic
flows, but those can be compensated for.

**The stealth F-117 had a rather interesting pressure probe
(conventional pitot tubes may not quite be corner reflectors, but
they're pretty close) with a facetted front, and used pressures
differences over some very small orifices to produce something akin to
airspeed and alpha data.  And in modes where reliable data really
mattered (like takeoff and landing), the F-117 cranked a "real" pitot
tube out from a covered compartment. 

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