RK Henry writes:

The similarity is that in both cases there's no hard connection
between the control surfaces and the flight controls. The DC-10 had no
cables between the controls and the flight surfaces, just pipes, so
with no hydraulic power there was no control action at all. But the
crew was left with control of the engines and that made it possible to
control the airplane.

True, but at least the control system didn't have a mind of its own.
It may stop working, but it isn't likely to start doing things that
the pilot doesn't want it to do.

My assertion is that there is insufficient
evidence to conclude that everyone would have died had the airplane
been FBW. Uncertainty remains as to that outcome.

From what I've read, they weren't even supposed to have survived the
accident as it was. I don't know if anyone ever managed to duplicate
their landing feat in a simulator (I've read that it has never been
successfully done in simulation).

However, much as it may disturb some other, less tolerant, members of
this group, I tend to agree with your qualms about FBW. FBW makes it
possible to implement exotic airframe designs by defining their flight
characteristics in software instead of in hardware. That's fine when
the pilot sits in an ejection seat, but when this technology is
extended to airplanes whose occupants don't have the option of pulling
a handle when things go badly then we must be very careful.

I agree. Furthermore, I just don't see a need for it. Just because
you can do it doesn't mean that you must or you should; it doesn't
even mean that you have anything to gain from it.

Military fighters need the best possible performance (or at least they
did, until they hit the obstacle of keeping pilots alive). FBW can
achieve that in certain situations, but at the expense of higher risk
for all flight in general. I don't see how any of this would be
applicable for general or commercial aviation.

I'm sure
the problems can be solved, probably with multiple redundancy, but a
century of experience with aviation shows that we must always consider
the possibility of failure.

Perhaps the problems can be solved, but if there is nothing to be
gained by FBW in the first place, why bother? Does anyone who flies a
plane for pleasure dream of being able to fly by just pushing one
button, or having a plane that does what it thinks is best, instead of
what the pilot tells it to do?

When planes are for pure transportation, perhaps that might argue in
favor of such systems, but in that case why bother keeping a pilot in
the cockpit at all? If FBW is completely reliable, you don't need a
pilot. If you need a pilot, then FBW is not completely reliable, and
the pilot needs a way to override it.

I've been similarly apprehensive about glass cockpits in light
aircraft. A single point of failure in an inadequately designed and
tested system could conceivably leave a pilot deaf, dumb, and blind.

And he would already be broke from paying for the avionics.

Wouldn't this also be a risk for any other aircraft?

Show me the test plan.

That's the part that worries me most. I know what passes for
"testing" in the world of computers, and it's an accident waiting to
happen. Yes, avionics are tested more thoroughly--but not thoroughly
enough. The failure modes multiply exponentially as gadgets and
features are added, and nobody is testing all the possible scenarios.

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