On Jun 20, 12:15 pm, Le Chaud Lapin wrote:

There are 100's, if not 1000's of features, that a general-purpose
computer + inexpensive, commoditized accessories, can add to flying.

I want to know which aircraft components can be
"commoditized," and what that means. Does it mean that ordinary
industrial or automotive bits are used in building the airplane? Where
can I get such commoditized cheap parts for my airplane? It needs new
wheels and brakes, which can't be replaced by car brakes because
they're all too big and heavy, it needs a new engine but that engine
has to weigh 178 pounds or less, it needs new radios that can tune in
aircraft fequencies. Can I buy those at JC Penney or Canadian Tire?

What is notable is that the cost of the $1000 PC does not increase.
Only the software and accessories change.

Of course, since billions of them are out there and many,
many millions more are sold every year. Not like airplanes at all.

We have some 172s and a 182 and a couple of Citabrias. These
airplanes all came with electromechanical voltage regulators, where a
small electromagnet pulls open the field current contacts to limit
alternator output. The 172s and 182 are all 1970s models and ran for
years and years and thousands of hours on those primitive make-and-
break buzzer-type regulators, and when they did quit we'd buy new
ones.
Now, the manufacturer makes regulators that look the same
and have the same part number, but the make-break contact setup has
been replaced with an electronic control circuit. No moving parts. And
those regulators last as little as a week and no more than a year or
two and cost every bit as much as the old style. What did we gain
there?
We fly in Canada where it can get really, really cold. The
epoxy cases on computer chips or transistor cases contract and crack
at -40 and moisture from the air gets in there and shorts them and
they're dead. Finished. This can happen when the unit is parked
outside, as they often are. Next time the pilot goes to use his
airplane the radio doesn't want to work right because the synthesized
tuner, which replaced a bank of switched crystals, is wandering all
over the place because its frequency counter chip is pooched. What did
we gain there? That radio weighs as much as the old crystal unit did
and lasted one fifth as long as the old one. What else would we use to
encapsulate a chip that wouldn't shrink and crack at -40? The LCD
displays on these things quit at -25 degrees. The liquid crystal
freezes. Useless. Narco uses a special gas discharge display in many
of their avionics, and that stupid thing burns out regularly. $350 for
each side of a NavComm. The old mechanically tuned radios keep on
going. What did we gain there?
I'm not against electronics. I've worked on electronic
devices since I was 14 years old, which was 41 years ago. It's just
that the "advances" we've been sold aren't ready yet and cost MORE
than the older ones did and are LESS reliable. We really haven't moved
ahead much at all and I would not trust my primary flight controls to
a single set of FBW controls. Airliners use three systems, just like
heavy trucks have three separate braking systems (but only one drum/
shoe per wheel) and such redundancy adds a lot of cost and weight.
Those 1/8" cables and their pulleys are going to be around for a long
time yet, believe me, and it's not because we don't want electronics,
it's because we can't trust them that much. My Power Mechanics teacher
in high school told us kids that 90% of all car problems would be
electrical, and in those many years since he's been proven right over
and over again.
The FAA is not against innovation and improvement. In the
early '70s a guy named Ken Rand took a set of Taylor Monoplane
blueprints (I once had one of those airplanes) and made some changes
and came up with the KR-1. It was the same size but much lighter and
slicker and went 50% faster, all using styrofoam and polyester fabric
and epoxy resins, and the idea caught on and Burt Rutan refined it and
built some astounding airplanes, paving the way for a host of new
designs. Lots of folks thought is was crap, and the composite airplane
still has lots of shortcomings (hard to repair, temperature extremes
are hard on it, resins are toxic, and lightning passing through it
tends to blow it to tiny bits) but we now have certified airplanes
like the Cirrus and composite propellers and composite tails on
airliners along with composite flaps and so forth, and the new 787 is
almost all composite. The FAA is happy with it and the 787, due to its
enormous strength, will have much better differential pressure for
higher cruise altitudes with lower cabin altitudes, so that its worst
fuel mileage will be better than the A380's best.
Stop dreaming about alternate propulsion methods and fancy
FBW systems and go invent and build them and if they make sense
they'll sell and you'll become rich and famous. Aviation is as market-
driven as anything else, and we're not resistant to innovation that
saves us money or makes us safer. But we WON'T buy something that
doesn't work as well as what we have now. Period.

Dan