Is it a habit we prefer mechnical instruments?

Morgans wrote:
"Le Chaud Lapin" wrote

Since the fuel gauage shown is being sold for 99 british pounds, I
don't think it would be too difficult to compete on a cost basis.

From your posts:

show altitude, IAS, TAS, average velocity, average acceleration, etc.
* show stress all over aircraft as colors correlated to degree of
[snippage]
* show air pressure, humidity, etc.
So that puts your system (before computer or displays) at 2800 pounds?

Humm.

That's just it. Most of the things I listed would cost far less than
$99 (let's switch to dollars for convenience). The reason that they
cost $99 or greater *now* is precisely because of the nature of the
supply chain.

Each component has a mechanical sensor and a display of some sort. The
mechanical sensor is unavoidable. But all of those displays can be
consolidated into one unit. The real question is, "How cheaply can
USB-based sensors of various sorts be manufactured?" I think the answer
is "very cheaply".

The problem is economics. Demand is relatively low, so the
manufacturers have to price units to make the effort worthwhile. But
as soon as the devices become truly commoditized, the prices will
become so low that the devices will become almost disposable. This has
already happened in electronics, were you can buy a 100Mb/s ethernet
adapter for $15. When you think about the technology that is involved
in creating a 100-meg ethernet adapter, it's simply incredible that you
can get one for less than cost of a meal for two.

I'd like to see the same thing happen in aviation. I'd like to see
commoditization of the sensors and controls. I'd like to see someone
make a USB-based humidity sensor, make it right, make it reliable, make
it cheap, and get out of the way. I'd like to see this done for all
the sensors.

If the manufactures did this, there would be other people who could
take care of the rest.

-Le Chaud Lapin-

"Morgans" wrote in message
...

"Peter Dohm" wrote

I read or heard the same, and don't recall the source or precise date,
except that it had to do with use of "non transmitting" electronics
(such
as
laptops and PDAs) in the cabins of airliners and corporate jets.

Right.

Was it AvWeb?
--
Jim in NC

I think so, but can't find the article.

Peter

Sounds great... until one of the Kiddies turns on "Automatic Updates"
and
the damn thing reboots on final in IMC... ~%=0

On Sun, 23 Apr 2006 18:13:06 -0400, "Morgans"
wrote:


"Le Chaud Lapin" wrote


RFI is hyped. Everytime somone operaters a laptop
or PDA in an aircraft, the are generating RFI. And besides, it's
something that is easily dealt with.

I wish I could point right to the bit I just read recently, saying that RFI
is *more* of an issue than was previously thought.

As is the susceptibility of GPS to solar storms and ground based
interference.

Roger Halstead (K8RI & ARRL life member)
(N833R, S# CD-2 Worlds oldest Debonair)
www.rogerhalstead.com

On Sun, 23 Apr 2006 20:03:31 -0400, "Peter Dohm"
wrote:

"Morgans" wrote in message
...

"Le Chaud Lapin" wrote


RFI is hyped. Everytime somone operaters a laptop
or PDA in an aircraft, the are generating RFI. And besides, it's
something that is easily dealt with.

I wish I could point right to the bit I just read recently, saying that
RFI
is *more* of an issue than was previously thought.
--
Jim in NC

I read or heard the same, and don't recall the source or precise date,
except that it had to do with use of "non transmitting" electronics (such as
laptops and PDAs) in the cabins of airliners and corporate jets.

Some computers are terrible radiators in the 100 - 150 MHz range.
I doubt they'd bother GPS unless they got in on an IF .

Just be happy the Chrysler V-6 with computer is not flying around up
there with us. They had one that put out a discrete and very strong
signal in the 2-meter ham band that could block a receiver up to a
city block away which made it the worst computer interference I've
seen so far.

Roger Halstead (K8RI & ARRL life member)
(N833R, S# CD-2 Worlds oldest Debonair)
www.rogerhalstead.com

Peter

Roger wrote: saying that RFI
is *more* of an issue than was previously thought.

As is the susceptibility of GPS to solar storms and ground based
interference.

Roger Halstead (K8RI & ARRL life member)
(N833R, S# CD-2 Worlds oldest Debonair)
www.rogerhalstead.com

Really?
I hadn't heard about sunspots and GPS. Does a GPS get funky or lose the
satellite signal when there's a lot of Northern Lights?

"Le Chaud Lapin" wrote in message
oups.com...

I think if you're about to take a trip, waiting the whole 17 seconds
for the OS to boot (Windows) won't hurt too much.


That is all very well when you are sitting in the coffee shop playing with
your laptop.

17 seconds without instruments on an instrument approach in solid IMC and it
will hurt a lot, but not for long.
Requiscat et Pacem ...

Highflyer
Highflight Aviation Services
Pinckneyville Airport ( PJY )

"Roger" wrote in message
news
The point I'm trying to make is for glass panels the code is kept as
compact as possible which means custom software that has to be
certified. These things are a long way from what sits on our desks.


Amen Roger,

The code bloat these days is absolutely phenomenal. Remember when you could
put a complete Unix system with all the accessories, bells, and whistles and
run thirty or forty users doing real work with only 16 megabytes of disk for
everything! And back it all up on a tape cartridge. :-)

I remember doing a simulator/training system for McD's that simulated four
combat missle launch platforms at the same time with all of their
instrumentation and readouts while moving them about independantly in the
simulation and letting them shoot missiles at each other. Each launch
platform could be any one of four choices and you made the change over by
merely unplugging the display panel and plugging in a different one. The
computer computed the positions of all the players and simulated all of the
instruments in real time. It even did the timing for response delays
throughout the system, which were different for each of the launch platform
choices.

I wrote the operating system and all of the control routines for this system
in Z80 assembler. It all ran memory resident on a Z80 8 bit processor with
64K bytes of memory and NO disk drive. If any of you remember, the Z80 did
NOT have fancy arithmetic instructions. All it had was add and subtract and
all of the range, bearing, square, square root, and arcsin and arccos
functions had to be done with a "shift and add" type algorithym. All of
this, along with system parameters and data for all of the various launch
platforms fit into the 64K byte memory with room to spare. And it ran in
real time with instrument update accuracy within a tenth of a second window.

Compared to that, a glass panel is simplicity itself and the old Z80 is
plenty of processor to do the job. I might point out, though, that NO
multitasking operating system really qualifies as a "real time" operating
system. Nothing Microsoft has ever put out qualifies for "real time."
Also, they, more than anyone, have made millions from "code bloat."

I used to run the EMACS editor in a 32K Z80 machine. For several users and
with all of the documents they were working in the various windows ( up to
ten windows each ) all in that little Z80 machine.

The machine code for Notepad wouldn't even fit in that machine!

Program it from scratch for reliability and remember, every line of code has
to be certified!

Highflyer
Highflight Aviation Services
Pinckneyville Airport ( PJY )

"Le Chaud Lapin" wrote in message
oups.com...
I disagree here. I've worked on digital communications systems for the
U.S. Department of Defense that were hardly cheap to get certified.
But no matter how expensive the certification, if you're making N of
them, the certification cost is amortized so that it is little more
than a temporary nuissance.

Certification cost on the order of several millions of dollars.
100 N 1000. Say certification 10,000,000 dollars ( a bit low but not
unreasonable )
That amortizes the certification cost out as between $10,000 and $100,000
per system. That is somewhat more than a "temporary nuissance" in my book.
So the computer only cost $500. Wheeeeee. Now the system cost is ONLY
$10500. :-) Yippeeee or should I say YIPE! :-)


And I believe this is the case for gadgetizing aircraft (and cars for
that matter). For all the speculation on complexity of programs,
sizes, cost, stranger danger, .....for a person skilled in *this*
field, meaning a software or electrical engineer (but not mechanical
engineer or pilot), the concerns are simply unfounded.


For the persons skilled in software or electrical engineering ( I taught
both at a major university ) the concerns are indeed unfounded. In fact
they are of no concern at all.

However, for the pilot ( I are one of those also, as well as a
mechanical/aeronautical engineer ) these are very real concerns and I have
yet to see any software engineer satisfy me to the point where I am willing
to bet my life, literally, on his ability to make them go away.

I am in a very bad position since I do indeed qualify as an expert as both a
software engineer and as a pilot. As a result I can see the simple
solutions and the wide range of problems on both sides of the equation.

It is possible to write simple clear and accurate code to make all kinds of
instruments work beautifully in either analog or digital modes and fly the
darn airplane too, and do it cheaply or relatively so. See the "Digitrak"
line of instruments and autopilots that were developed by a friend of mine
( who is a contempory of mine in age also ) and who is a top notch
electrical engineer and a top notch pilot as well. Notice also that he
elected to avoid the "certification process" required to utilize these
instruments and autopilots in type certified aircraft. For obvious reasons
cited above! He went through that particular can of worms when he
developed the Century series of autopilots some years ago. Never again ...

Highflyer
Highflight Aviation Services
Pinckneyville Airport ( PJY )



What's happening right now is that companies like Garmin are doing this
so slowly that it is hard to see that it's happening.

-Le Chaud Lapin-

"Richard Lamb" wrote in message
...

As for the mechanical gages?

One that is woefully lacking is an off-the-shelf low value amp meter.
(more precisely ('cuz Jim's watching) - one that might have interchangable
shunts?) 60/30/15 amp display?

I run a 15 AH battery. A 60 amp meter tells me nothing.

Richard


I bought one that has two needles and scales. It functions as a volt meter
and an ammeter simultaneously. The shunt is external and mounts outside the
meter where it connects into the buss system under the panel. Shunts are
available for a number of different ranges with 60 amp being the highest
value available. Other than having to buy the meter and the shunt
separately, because of the range of different shunts available, it was
certainly "off the shelf". I found it in the Wick's catalog and they
shipped it the same day from stock.

Highflyer
Highflight Aviation Services
Pinckneyville Airport ( PJY )