FADEC = complex

Jose writes:

Another example is fighting the autopilot... if you push the nose down,
the autopilot will compensate by trimming up to maintain altitude. It
will do this until it can no longer compensate, then it disengages,
which is a surprise to the unaware pilot.

I think that's the kind of thing he may be referring to.

Yes. As a general rule, automation systems greatly reduce situational
awareness. That is necessary for them to accomplish their purpose,
but it is also dangerous. Problems arise when human beings forget
that automation does this (unfortunately they forget this very
easily).

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Morgans writes:

He is taking about something that has no relation to FADEC.

FADEC is one form of automation; autopilot is another. They are
variations on the same theme.

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Neil Gould writes:

One gets plenty of clues that something is going awry prior to this
happening.

No, one does not. The whole purpose of automation is to mask
information that contains such clues, in order to reduce the workload
for the pilot. As an autopilot moves the ailerons of an aircraft to
maintain heading and attitude, this is completely transparent to the
pilot for the most part, unless he actually looks out at the ailerons
or keeps his hands on the controls (in some aircraft). If he were
constantly being reminded of the autopilot's actions, there wouldn't
be any advantage to having an autopilot.

It appears that you are describing another form of pilot error. If one
believes that they can set an autopilot and then take a nap, *that* is the
problem, not the behavior of the autopilot.

A lot of commercial pilots do that. Long trips can get pretty boring.

Given that so few accidents can be charged to the failure of these
devices, it may be reaching to claim that some unreasonable level
of danger is presented by their use.

A lot of accidents have occurred when automated systems allowed crews
to lose their situational awareness. Autopilots are particularly
implicated in this respect, perhaps because they've been around so
long and work so well.

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Morgans writes:

What does FADEC have to do with controll surfaces.

Autopilots work by manipulating control surfaces. FADECs work by
manipulating engine controls. Both are forms of automation that can
reduce situational awareness.

FADEC has warnings that are activated when there is a problem with any of the
redundant systems.

But there doesn't have to be a problem with the systems. You can lose
situational awareness when they are operating perfectly. Indeed,
that's the situation in which you are most likely to lose situational
awareness.

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Kev writes:

Of course, neither setup can prevent a sudden cylinder failure, or oil
pump, or fuel pump, or vacuum pump, or other such mechanical
commonality.

Note, however, that digital systems are _far_ more likely to react to
unexpected events in a very extreme way. An oil-pump failure can
cause a catastrophic system failure almost instantly if the digital
system isn't designed to take into account the possibility of an
oil-pump failure.

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Morgans wrote:
"Mxsmanic" wrote
[...]
What does FADEC have to do with controll surfaces. FADEC has nothing to do with
control surfaces, or autopilot, or fly-by-wire. Get that in your head.

You're out of date. The term "fly-by-wire" includes FADEC these days.
See wikipedia, Google, yadda yadda.

One of the problems with "intelligent" systems is that they can
conceal problems until they become so serious that they cannot be
corrected, at which point they produce catastrophic, irrecoverable
failures.

FADEC has warnings that are activated when there is a problem with any of the
redundant systems.

Like any software, it only has preset warnings for problems the
programmer knows about or can predict. A good example of this kind of
failure was with the early Patriot missile system. Although it had
various warnings built in, there was no warning when its internal clock
rolled over (due to a common programmer error in setting the clock data
size). This caused several bad shots in the first Gulf War, including
the one that caused the incoming Scud to hit our troops' mess hall.

Kev

Morgans wrote:
Why are you defending him?

Don't you get it yet? People aren't defending him (I don't think he
requires it), as much as they're saying that they don't like YOUR kind
of behavior. They see you and your ilk as more of a threat to this
newsgroup than he ever could be.

1) Everyone loves an underdog. By insulting him all the time,
deserved or not, you have generated sympathy for him.

2) No one likes a bully, a gang or mob mentality. You and your
buddies on the attack seem like a gang of thugs sitting on a street
corner yelling insults, trying to look cool. But you aren't.

3) You try to defend your actions by saying that someone might mistake
his "information" as real. Unfortunately, and especially in this
thread (among others), the people casting insults have been shown to be
pretty much uninformed on the topic, making you the threat. Worse,
when called on your lack of knowledge, you resorted to more attacks.

4) You continue to tell everyone else to whom they should respond or
not. No one appreciates that. This is Usenet, not your personal
group.

5) By using personal attacks as a means of arguing facts, you've
opened yourself up to personal attack. Yet so far, people have been
nicer to you, than you have been to others.

You really need to take a long hard look at yourself, bud, and turn
your head 180 degrees around.

Kev

Greg Farris wrote:
In article . com,
says...
But judging from my forty years' experience with automobile engines
(including having rebuilt my share as a youth), I would have to agree
with Mxsmanic that you're far more likely to have a sudden unannounced
failure with a FADEC system than with a traditional mechanical system,
where some warning (slack in the controls, engine output not up to par,
etc) is often forthcoming.

Well, that's a brilliant non-sequitor!
It is less surprising that you systematically defend this maniac, when we see
that you share the same deficient logic! Would you please care to tell us how
rebuilding car engines as a kid permits you to make otherwise unsubstantiated
claims about failure modes of FADEC systems in aircraft?

Don't act so dumb. It means that I have rather a large experience with
engines and their failure modes, having worked as a mechanic for a
living. I've also been one of the top embedded programmers in the
world. My claims are based on decades of embedded experience.

What are your qualifications?

Kev

Bob Gardner wrote:
The feds have just designated a plane with retractable gear, flaps, and
FADEC as a complex.

For anyone who wants to read it, here's the notice:

http://download.aopa.org/epilot/2006...6faapolicy.pdf

It mentions that, so far, only the DA42 meets this particular
definition.

Kev

Kev wrote:
Bob Gardner wrote:
The feds have just designated a plane with retractable gear, flaps, and
FADEC as a complex.

For anyone who wants to read it, here's the notice:

http://download.aopa.org/epilot/2006...6faapolicy.pdf

Hmm. This is great news for those getting a commercial or instructor
certificate.

But it means that a potential aircraft owner would need a complex
sign-off even if the propeller is automatically controlled by the
FADEC.

Does that seem fair, considering the previous definition of a complex
aircraft? It seems to me that one of the reasons for building an
aircraft with such an automatic system would be to make it more
available to pilots.

Kev