A question for the future

(C Kingsbury) wrote in
om:

Andrew Sarangan wrote in message
.158...
"Neil Gould" wrote in
news
Recently, Andrew Sarangan posted:

The same thing was said about glass cockpits. Now even the ubiquitous
172 comes with a glass cockpit. It won't be long before the backup
vacuum driven gyros are removed from their panel.

And with good reason: just as transistors proved more reliable than
vacuum tubes, solid-state AHRS look to be far more reliable than their
replacement. There's a huge benefit to safety, utility, and ultimately
cost by making the move.

However, I would not want to give up the non-powered wet compass,
altimeter, and airspeed indicator completely. Not until we prove that
mice can't chew through wires, etc. What's the benefit of tossing
these completely?

Likewise, I suspect navigating by reference to magnetic north will be
one of those charming anachronisms that our descendants 2000 years ago
will talk about in the same way that people today talk about how
railroad gauges were based on roman roads. (I know it's true only in a
loose sense, no need to rehash that here)

You can't count the number of components in a circuit and assign
failure modes to each one of them. If that were the case, your
computer will not be able to run for even a minute. There are
millions of transistors inside your computer, with million different
failure modes. The traditional method of counting failure modes of
mechanical parts do not apply to highly integrated electronic
products. Yes, there are a few failure modes, but not as large as you
make it out to be.

Um, I'm calling bull**** on this assertion. Isn't the real key here
that the odds of a particular part (say a transistor gate inside a
CPU) failing are simply infinitesimally small? Because if one
capacitor on your PC motherboard smokes out, it's quite likely that
the whole shebang will in fact not work properly.

Best,
-cwk.



The real key is that all the transistors on a chip are made on the same
substrate. They share all the same characteristics. The failure of one
transistor is not an uncorrelated event from another transistor failing.
They all fail more or less at once, or they all continue to function.
They behave as single component. Just because there are millions of
transistor on a chip does not mean that there are millions of different
failure modes. There are only a handful of failure modes regardless of
the number of transistors on the chip. This is what is fundamentally
different about integrated circuits compared to discrete circuits.

"B25flyer" wrote in message
...

Over a period of time aviation seems to make changes due to technical
advances.
As such in the past certain "basics" of aviation that were once written in
stone have gone by the wayside.

So here is one for ya. Last week I started a student on the ground school
basics of cross country planing. Draw the line on the sectional from
airport to
airport. Discuss all the wind, magnetic and other variables etc. After
about 20
minutes into the discussion the students 13 year old daughter who was
intently
watching asked the question. "Why do all that when I can do the same thing
in
30 seconds on the handheld GPS and enroute it will take care of the wind
correction"

Got me to thinking. So question is, what is the opinion of the troops as
to
when the system will change and as part of the written/PTS for any rating
there
will no longer be the requirment to draw the line and figure out all the
other
stuff for the X-C portion of the test. Just put in airports/waypoints and
go
for it.

Five years? Ten years? Or will it stick around forever?

Walt
Forty+ years as a CFI and still drawing lines on sectionals.

Interesting question...
I'm a pretty new PP-ASEL, and somewhat of a technology junkie.
I'm in the process of purchasing my 1st airplane.
I pick it up in about 2 weeks.
It's in TX, and I'm in NV...about 1200nm.
The plane comes with a GPS, so I'll use it.
I've also planned the trip to intersect every VOR (or a radial) along the
way.
I've also drawn the line across four different sectional charts.
My thinking is that if something goes wrong with the GPS, I can use the
VORs.
And I ALWAYS like to look outside and say, "Yup, there's that dry lake bed,
just like on the chart".
I actually drew the lines on the chart first, then got the waypoints to put
into the GPS...

Another poster mentioned that a GPS can go tango uniform, which is true...
If I was stuck in a plane without a chart, I'd want TWO completely redundant
GPS units...

Adam

"B25flyer" wrote in message Forty+ years as a CFI and still drawing lines
on sectionals.

Still drawing lines on sectionals?
I simply fold the chart along the courseline. That way, I don't have to buy
a new one for years.

D. (What's the kid going to do when the magic box craps out and she doesn't
know the basics?)

Still drawing lines on sectionals?

I simply fold the chart along the courseline.


Been flying since 1980 and I never thought of that!

To answer the underlying question (why not let the GPS do all your flight
planning) I'd ask back why not let the autopilot do all the flying, and take a
snooze in the back seat?

1) charts have few catastrophic failure modes
2) perusing the chart before a flight alerts me to special use airspace, high
towers, terrain, stuff like that (especially important when one flies low, as I
am wont to do)
3) it's part of the fun of flying - doing it yourself as opposed to
surrendering to something by Garmin
4) what you've planned yourself you'll recognize more easily than what's
handed to you on a screen.

Jose


--
(for Email, make the obvious changes in my address)

GPS can fail for a variety of reasons, not all are "technical issues
which will eventually be solved". Interference is a growing issue for
example. Batteries die, wired connectors stop connecting, and
sometimes electronic components just plain stop working. Don't get me
wrong, I like the GPS, I think it's pretty useful and cool as well.
But, being a belt-and-suspenders man, I like having and knowing how to
use backups too.

While the PTS may not require doing calculations by hand, examiners can
and do "fail" GPS devices and expect the applicant to perform well no
matter what. As would your passengers if this happened in real life.
-Malcolm Teas