Today's Message Index:
----------------------
1. 05:55 AM - Re: Re: 02/07/05 A Forced Landing (Ken)
2. 06:37 AM - Starter motor voltage (Jan de Jong)
3. 06:46 AM - Re: Re: 02/07/05 A Forced Landing (Robert L. Nuckolls, III)
4. 06:46 AM - Re: Ground plane questions... (Robert L. Nuckolls, III)
5. 06:53 AM - Re: astute observers of the human condition (Robert L. Nuckolls, III)
6. 07:29 AM - Re: Re: 02/07/05 A Forced Landing (Matt Prather)
7. 08:34 AM - Re: 02/07/05 A Forced Landing (Eric M. Jones)
8. 08:43 AM - Re: Shielded magneto wires - Z Figures (Robert L. Nuckolls, III)
9. 08:54 AM - Re: Starting Power (Robert L. Nuckolls, III)
10. 12:21 PM - Re: 02/07/05 A Forced Landing (Matthew Brandes)
11. 12:41 PM - Audio warning system (Glaeser, Dennis A)
12. 01:09 PM - Re: Starter motor voltage (Robert L. Nuckolls, III)
13. 01:10 PM - Re: Re: 02/07/05 A Forced Landing (Robert L. Nuckolls, III)
14. 01:23 PM - Re: Re: 02/07/05 A Forced Landing (Dj Merrill)
15. 01:34 PM - Re: Re: 02/07/05 A Forced Landing (Terry Watson)
16. 02:50 PM - Re: Re: 02/07/05 A Forced Landing (Dj Merrill)
17. 03:09 PM - Re: Re: 02/07/05 A Forced Landing (Terry Watson)
18. 03:58 PM - Re: Starting Power (Mike Gregory)
19. 04:43 PM - 2-10 switched fuel pump (TimRhod@aol.com)
20. 05:01 PM - Re: Re: 02/07/05 A Forced Landing (Tom Brusehaver)
21. 05:18 PM - Fuseable Link question (Charlie Kuss)
22. 06:34 PM - Re: Re: 02/07/05 A Forced Landing (Richard Riley)
23. 06:52 PM - Corbalis' Buzzer (Speedy11@aol.com)
24. 08:02 PM - Re: 2-10 switched fuel pump (John Schroeder)
25. 08:21 PM - Re: Re: 02/07/05 A Forced Landing (Fiveonepw@aol.com)
26. 09:13 PM - Re: Starting Power (Robert L. Nuckolls, III)
Message 1
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| Subject: | Re: 02/07/05 A Forced Landing |
--> AeroElectric-List message posted by: Ken <klehman@albedo.net>
Sounds like silly FAA deskjockey talk to me! I agree that status
indicators should not flash but warning and caution lights?
Surely nobody ignores a flashing light until explaining it. Removing a
faulted flickering light bulb on extremely rare occasion is trivial.
Flickering is not likely to be confused with flashing anyway. A
light that isn't noticed is useless.
Ken
George Braly wrote:
>--> AeroElectric-List message posted by: "George Braly" <gwbraly@gami.com>
>
>Bob,
>
>A recent visit with the FAA reveals they are opposed to "flashing"
warning or caution lights.
>
>They claim it is too easy to dismiss them as being simply "faulty" lights.
>
>Rather than lights indicating a fault.
>
>Regards, George
>
>
Message 2
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| Subject: | Starter motor voltage |
--> AeroElectric-List message posted by: Jan de Jong <jan.de.jong@xs4all.nl>
I would like to know what happens to voltage across the starter motor
when current is interrupted. It probably depends on whether the motor is
running or stalled at the moment of interruption.
In the first case I would guess a gentle decay from battery voltage to
zero as the motor stops spinning. In the second case there might be a
negative voltage excursion?
A negative voltage excursion, added to the battery voltage, could exceed
the breakdown voltage of a solid state contacter.
Also, when the battery contacter is used as a backup for a welded-closed
starter contacter the negative voltage spike would appear on the bus.
A powerdiode Schottky clamp would be a solution. But only if there is a
problem.
Does somebody have data or a categorical opinion?
Jan de Jong
Message 3
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| Subject: | Re: 02/07/05 A Forced Landing |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <b.nuckolls@cox.net>
At 08:53 AM 2/18/2005 -0500, you wrote:
>--> AeroElectric-List message posted by: Ken <klehman@albedo.net>
>
>Sounds like silly FAA deskjockey talk to me! I agree that status
>indicators should not flash but warning and caution lights?
>Surely nobody ignores a flashing light until explaining it. Removing a
>faulted flickering light bulb on extremely rare occasion is trivial.
>Flickering is not likely to be confused with flashing anyway. A
>light that isn't noticed is useless.
The philosophy of minimizing flashing lights has some
foundation in practice. I think our Hawkers have a
bright/dim mode for the annunciator array itself and
they only flash the master caution/warning (MCW) buttons in
front of the pilots.
When an annunication first presents, it's much brighter
on the array and easy to pick out amongst any other
annunciations already lit. The MCW buttons flash and
you get alarm tones in the audio system. Once the
crew's acknowledges the new condition, the MCW buttons
go dark, the tones go away and the most recently
added annunciations go dim with the rest.
The idea isn't all that whacky but there is precedence
in the brotherhood of pilots for learning to fly with
this style of presentation. Like KEN, I am skeptical
of the value of this . . . as a pilot of an OBAM aircraft,
I'm sure I could become comfortable and confident with
the flashing scenario too.
The fact remains, getting the pilot's attention with
timely and concise information is the primary design
goal. After that, debates about dimming, flashing,
colors and font sizes won't add a great deal of value
beyond accomplishment of the primary goal.
So my friends, if your LOW VOLTS WARNING light is
not of the intensity and location to get your timely
attention, please consider relocating it and/or
going to a higher intensity lamp. This simple
condition would probably have saved our brother pilot
from wrinkling a lot of sheet metal.
Bob . . .
Message 4
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| Subject: | Re: Ground plane questions... |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <b.nuckolls@cox.net>
Malcom,
I was sorting though the out-box of my email client and found this
response to your query that wasn't sent. My apologies. I had good
intentions but didn't get the task finished by hitting the "send"
button.
Bob . . .
At 05:51 PM 12/15/2004 -0700, you wrote:
>--> AeroElectric-List message posted by: "Malcolm Thomson"
><mdthomson@attglobal.net>
>
>I'm building a Thunder Mustang which is almost 100% carbon fiber. My
>questions are:
>
>1. Do antennas which receive only (ILS/VOR/Marker) need ground planes
>and if so what size.
These are generally horizontally polarized dipoles and do not require
a ground plane. Only VHF COM, Transponders and some marker beacon antennas
need ground planes.
>2. Can a "spray-on" metal coating be used?
Generally no. It's difficult to achieve long lasting,
low resistance connections to such coatings on the
surface of a composite structure.
>3. For Com antenna's how big must the ground plane be (minimum and
>preferred sizes)?
Ground plane radius is same as length of the antenna.
>4. If the ground plane is on the inside of the aircraft (opposite side
>of the carbon skin than the antenna) does it still work?
Yes.
>5. Does the ground plane have to be made of sheet metal and be shaped
>round, square or do strips of copper tape work?
4-8 strips of copper or aluminum same length as antenna and
1/2 to 1-inch wide with GOOD electrical connection to the
coax connector's shell will be fine.
Message 5
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| Subject: | Re: astute observers of the human condition |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <b.nuckolls@cox.net>
At 03:05 PM 10/29/2004 -0400, you wrote:
>--> AeroElectric-List message posted by: Brian Lloyd <brianl@lloyd.com>
>
>
>Ah Bob, a man who quotes Heinlein is a man after my own heart.
>
>Brian Lloyd 6501 Red Hook Plaza
>brianl@lloyd.com Suite 201
>+1.340.998.9447 St. Thomas, VI 00802
>
>A human being should be able to change a diaper, plan an invasion,
>butcher a hog, conn a ship, design a building, write a sonnet, balance
>accounts, build a wall, set a bone, comfort the dying, take orders,
>give orders, cooperate, act alone, solve equations, analyze a new
>problem, pitch manure, program a computer, cook a tasty meal, fight
>efficiently, die gallantly. Specialization is for insects.
>
>--Lazarus Long (AKA Robert A. Heinlein)
I've been a minor student of good teachers for a number of
years. I'm delighted to find that they are oft discovered in
the most unexpected places and times. The neatest thing about
these folk is that concepts offered are as timeless,
lucid and worthy of the label "simple idea" as Ohm's Law,
class I levers, or stoichiometric combustion. During the
heat of political debate I often consider and take guidance
from these clear headed thinkers of the past.
Bob . . .
--------------------------------------------------------
( "He who exercises government by means of his virtue )
( may be compared to the north polar star, which keeps )
( its place and all the stars turn towards it. If the )
( people be led by laws, and uniformity sought to be )
( given them by punishments, they will try to avoid )
( the punishment, but have no sense of shame. If they )
( be led by virtue, and uniformity sought to be given )
( them by the rules of propriety, they will have the )
( sense of shame, and moreover will become good." )
( Confucius 551-479 B.C. )
--------------------------------------------------------
Message 6
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| Subject: | Re: 02/07/05 A Forced Landing |
--> AeroElectric-List message posted by: "Matt Prather" <mprather@spro.net>
How about flashing the light in sync with a warning tone. It seems
unlikely a buzzer would just happen to have the same fault as the
light.
Regards,
Matt
> --> AeroElectric-List message posted by: Ken <klehman@albedo.net>
>
> Sounds like silly FAA deskjockey talk to me! I agree that status
> indicators should not flash but warning and caution lights?
> Surely nobody ignores a flashing light until explaining it. Removing a
> faulted flickering light bulb on extremely rare occasion is trivial.
> Flickering is not likely to be confused with flashing anyway. A
> light that isn't noticed is useless.
> Ken
>
> George Braly wrote:
>
> >--> AeroElectric-List message posted by: "George Braly"
> <gwbraly@gami.com>
> >
> >Bob,
> >
> >A recent visit with the FAA reveals they are opposed to "flashing"
> warning or caution lights.
> >
> >They claim it is too easy to dismiss them as being simply "faulty"
> lights.
> >
> >Rather than lights indicating a fault.
> >
> >Regards, George
> >
> >
>
>
Message 7
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| Subject: | Re: 02/07/05 A Forced Landing |
--> AeroElectric-List message posted by: "Eric M. Jones" <emjones@charter.net>
Flashing lights, buzzers, horns and beepers......reminds me of Three Mile
Island. I'm still wondering how I can execute the proper sequence to save my
life when my electrical system goes down....Let's see flip this switch up,
pull this, cutoff that....call Bob.....
It is now reasonably trivial to have voice warnings. One of the toys in the
box of prototypes (I'll get to it soon.....) is a tiny little 12 second max
voice chip module. Less than a square inch....but imagine the tons of
mischief one can do with it....Or helpful warnings.
And who says electronics isn't fun!
Regards,
Eric M. Jones
www.PerihelionDesign.com
113 Brentwood Drive
Southbridge MA 01550-2705
Phone (508) 764-2072
Email: emjones@charter.net
"Few people are capable of expressing with equanimity opinions which differ
from the prejudices of their social environment. Most people are even
incapable of forming such opinions." -- Albert Einstein
Message 8
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| Subject: | Re: Shielded magneto wires - Z Figures |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <b.nuckolls@cox.net>
At 06:06 PM 9/1/2004 -0400, you wrote:
Walter,
Just discovered this unsent message in my outbound mail box. My appologies
for leaving you hanging.
First, have you fixed this problem? If so, what was the solution? If it's
still hanging around, see my belated comments below:
>--> AeroElectric-List message posted by: Walter Tondu <walter@tondu.com>
>
>On 09/01 11:19, Werner Schneider wrote:
>
> > --> AeroElectric-List message posted by: "Werner Schneider"
> <wernerschneider@compuserve.com>
> >
> > > > >
> > > >Forgot to mention, I believe it is the alternator as when I
> increase load
> > > >(switch things on) the sound changes.
> > >
> > > aha! excellent data point. This almost always points to
> > > a ground loop. You have more than one ground for avionics/audio
> > > equipment that's reading high current ground returns for high
> > > current equipment like landing lights, pitot heat, etc.
> > >
> > Hello Bob,
> >
> > interesting, I followed the recommendation and grounded each and every
> > equipment to the single 48-tab ground block from B&C, but my panel is
> metal
> > and the avionics rack are directly screwed onto the aluminum as well
> as the
> > whole panel is hinged on the metal cage, I added a separate ground
> from the
> > tab block to the panel but no change. The Battery is connected with a 2AWG
> > cable to the ground tab, on the other side of the firewall a braided cable
> > is going to the engine crankcase.
> >
> > As told the noise is very low and maybe only audible to me because of the
> > ANR headset.
> >
> > What is the best way to tackle this? Should I build the milliohmmeter from
> > Figure 5-3 to investigate and where to lock first, what about if the noise
> > is not there with stopped engine (have to listen next time).
If your avionics find any kind of electrical ground through the
mountings, then there's not much you can do about it . . . you've
got multiple grounds by design. When we write a specification for
any potential victim accessory, we always ask that power and signal
grounds NOT be internally connected to the enclosure. Enclosures
get local ground by virtue of their mechanical mounting . . . we like
to have control of where the signal and power grounds fine their
way to the airplane's ground system. Most of the time, the first
whack at an installation simply attaches the "special" grounds to
the airframe adjacent to the appliance.
I'm working a situation right now in an airplane where a VERY
special ground for the remote display of some radios was poorly
selected. The critter wanders off into the weeds from time to
time and needs a power-up reset to recover. I'm 90% certain that
we'll fix this by repositioning a ground wire. (I won't elaborate
on my opinion of the designed-in vulnerability to this problem).
It may be that you would do well to ground all your avionics
to a separate ground right on or near the avionics tray. This
at least side-steps the built-in vulnerability to ground loops
caused by internal grounding of one or more accessories to the
enclosure.
I'm writing a new chapter for Rev 11 of the 'Connection where
I'll propose a local avionics ground just as I've described.
Lancair has adopted this practice in their panel build shop
and I discussed it with their techs when I did a weekend seminar
in their shop some time ago. They used a terminal block like
this:
http://www.aeroelectric.com/Pictures/Terminal_Strip_Captive_Stud.jpg
This is certainly a CAPABLE product but I think overly
robust for this task. I published a picture of a ground
block fabricated from a D-sub connector a couple of years
ago but I can't put my hands on it. I'm laid out a board
and ordered parts for an avionics ground bus kit. Parts
should be here next week and I'll get the kit up on the
website soon after.
Wiring concept for the avionics ground is illustrated
here:
http://www.aeroelectric.com/Pictures/Avionics_Ground_Bus.gif
>Are both Mags grounded to the ground block as well?
No . . . wire mags exactly as shown in the Z-figures. Ground
shield at or close to mags on engine end and use shields to
PROVIDE ground for switches at panel end. Add no other grounds.
Bob . . .
Message 9
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| Subject: | Re: Starting Power |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <rnuckolls@aeroelectric.com>
At 01:36 PM 8/19/2004 -0400, you wrote:
>--> AeroElectric-List message posted by: Matt Jurotich
><mjurotich@hst.nasa.gov>
>
>I recall a long discussion about this with reference to lightspeed
>ignitions. One of the solutions proposed was a large capacitor. Did this
>require a blocking diode or ?? so the capacitor would last for a few seconds?
>
>By the way, BlueMountain is very clear about needing a second battery to
>prevent a reset during starting if you want the engine gauges built into
>the EFIS One immediately upon start up. Would this capacitor trick work
>with their 3 amp requirement?
There are several schemes that might support the supply voltage
to these products for milliseconds to seconds required to get
past starter inrush transients. It's relatively easy to size
the capacitor needed:
1 ampere of current flowing into a 1 farad capacitor causes
it to change voltage by 1 volt per second. Nice neat relationship.
Let's assume device to be pampered needs 2 A at minimum voltage
(lets say 10 volts) to stay alive. You're starting with a hopefully
good battery at 12.5 volts. Feed capacitor with a Schottky diode
so it starts from 12.0 volts. Let's say that the capacitor needs
to support the 2A drain for 100 milliseconds. Okay
2 volts delta, 2A, .1 seconds.
I/C = V/S
2/C = 2/.1
2/C = 20
C = 10 Farads
Hmmm . . . that's a pretty fat capacitor. Impossible to consider
a few years ago but in the realm of possibilities now. If we were
supporting a shorter duration of brown-out, say 10 milliseconds,
then a 1 Farad capacitor gets us by. You see how this works?
For the most part, a small battery can masquerade as a capacitor
that is physically much larger in size and weight. As a general
rule, the brown-out battery is a better choice from the perspective
of sized and weight.
I've used capacitors for this very task but at much lower
currents where perhaps 1,000 microfarads will do the trick.
Bob . . .
Message 10
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| Subject: | RE: 02/07/05 A Forced Landing |
--> AeroElectric-List message posted by: "Matthew Brandes" <matthew@n523rv.com>
Not sure if everyone is aware or not.... but Van's sells a flashing LV
light:
http://www.vansaircraft.com/cgi-bin/catalog.cgi?ident=1108757653-384-9&brows
e=electrical&product=alt-warning
Alternator Monitor Warning Light
Description
-----------
This is a simple but effective warning light designed to monitor alternator
operation. This unit will automatically light when the aircraft system
voltage drops below 13 VDC. Circumstances that might produce this are a
failed alternator or a master switch left on after engine shutdown.
The unit flashes for 10 seconds then goes to constant illumination when
voltage drops below 13 volts. This feature sets it apart from other
annunciators. The flashing draws attention to the condition then remains
illuminated so as not to be a pilot distraction thereafter.
An ideal alert for the absentminded!
Message 11
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| Subject: | Audio warning system |
--> AeroElectric-List message posted by: "Glaeser, Dennis A" <dennis.glaeser@EDS.COM>
I want the voice of HAL from 2001 a Space Odyssey to say "Dennis, your
alternator seems to be having a problem" (too bad my name isn't Dave).
"call Bob" reminds me of your comment a while back about a panic button
which would do that. Anyone who has a recent vintage GM vehicle actually
has such a button - they call it OnStar. I'm sure Bob appreciates that it
doesn't call him. Put that in your airplane and you could have the
concierge arrange for a tee time as you glide in for a landing on the golf
course ...
Dennis Glaeser
Do not archive
------ original message ------
Flashing lights, buzzers, horns and beepers......reminds me of Three Mile
Island. I'm still wondering how I can execute the proper sequence to save my
life when my electrical system goes down....Let's see flip this switch up,
pull this, cutoff that....call Bob.....
It is now reasonably trivial to have voice warnings. One of the toys in the
box of prototypes (I'll get to it soon.....) is a tiny little 12 second max
voice chip module. Less than a square inch....but imagine the tons of
mischief one can do with it....Or helpful warnings.
And who says electronics isn't fun!
Regards,
Eric M. Jones
www.PerihelionDesign.com <www.PerihelionDesign.com>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2//EN">
<META NAME"Generator" CONTENT"MS Exchange Server version 5.5.2657.73">
Audio warning system
I want the voice of HAL from 2001 a Space Odyssey to say Dennis, your alternator
seems to be having a problem (too bad my name isn't Dave).
call Bob reminds me of your comment a while back about a panic button which would
do that. Anyone who has a recent vintage GM vehicle actually has such a button
- they call it OnStar. I'm sure Bob appreciates that it doesn't call him.
Put that in your airplane and you could have the concierge arrange for a tee time
as you glide in for a landing on the golf course ...
Dennis Glaeser
Do not archive
------ original message ------
Flashing lights, buzzers, horns and beepers......reminds me of Three Mile
Island. I'm still wondering how I can execute the proper sequence to save my
life when my electrical system goes down....Let's see flip this switch up,
pull this, cutoff that....call Bob.....
It is now reasonably trivial to have voice warnings. One of the toys in the
box of prototypes (I'll get to it soon.....) is a tiny little 12 second max
voice chip module. Less than a square inch....but imagine the tons of
mischief one can do with it....Or helpful warnings.
And who says electronics isn't fun!
Regards,
Eric M. Jones
www.PerihelionDesign.com
Message 12
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| Subject: | Re: Starter motor voltage |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <b.nuckolls@cox.net>
At 03:45 PM 2/18/2005 +0100, you wrote:
>--> AeroElectric-List message posted by: Jan de Jong <jan.de.jong@xs4all.nl>
>
>I would like to know what happens to voltage across the starter motor
>when current is interrupted. It probably depends on whether the motor is
>running or stalled at the moment of interruption.
>In the first case I would guess a gentle decay from battery voltage to
>zero as the motor stops spinning. In the second case there might be a
>negative voltage excursion?
>A negative voltage excursion, added to the battery voltage, could exceed
>the breakdown voltage of a solid state contacter.
>Also, when the battery contacter is used as a backup for a welded-closed
>starter contacter the negative voltage spike would appear on the bus.
>A powerdiode Schottky clamp would be a solution. But only if there is a
>problem.
>Does somebody have data or a categorical opinion?
There is a RICH history of DC cranking motors and controlling
devices that go back to Charles Kettering's first efforts to
take the engine crank off the Cadillac in 1912 or so. See:
http://www.ehistory.com/world/amit/display.cfm?amit_id=2327
There is good reason to believe that the inductive nature of
motors and even the wiring used to power them will exhibit some
dynamic effects for the interrupted current flow. You're also
correct that those characteristics will vary depending on speed
and load on the motor at the time of interruption . . . and on
the design of the motor (wound field or permanent magnet).
Energy dumped from the starter has been blamed for a variety
of system ills but the concept didn't take off until we started
bolting 30 volt, germanium transistor to radios and the production
lines experienced too many but not understood failures of
transistors . . . must be "starter spikes" that got 'em.
I've not taken the time to quantify the magnitude and
duration of the transients. It's a low priority given that
a wealth of solid state products seem to live happily tied
to the bus without benefit of an avionics master switch
or special treatment to avoid subjecting the product to
vagaries of the bus during all kinds of cranking scenarios
not only on airplanes but hundreds of millions of cars.
I agree that a solid state starter contactor would be
the most vulnerable to the effects. I would hope that
any supplier of solid state contactors has explored and
identified and accounted for all the spiders and snakes
that live in the world where their product will live.
Until some folk on the list with a test setup, measurement
equipment and time can go "get the numbers", there will
be no advice backed with measurements. I think the risks
are low but it's a good question to ask of the supplier
of any contactor offered for this service.
It would be pretty easy to get some data off a vehicle that
has a starter controlled by external contactor. Lots of
old Ford products have this setup. I'll keep an eye
out for a test subject.
Bob . . .
Message 13
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| Subject: | Re: 02/07/05 A Forced Landing |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <b.nuckolls@cox.net>
At 11:39 AM 2/18/2005 -0500, you wrote:
>--> AeroElectric-List message posted by: "Eric M. Jones" <emjones@charter.net>
>
>
>Flashing lights, buzzers, horns and beepers......reminds me of Three Mile
>Island. I'm still wondering how I can execute the proper sequence to save my
>life when my electrical system goes down....Let's see flip this switch up,
>pull this, cutoff that....call Bob.....
>
>It is now reasonably trivial to have voice warnings. One of the toys in the
>box of prototypes (I'll get to it soon.....) is a tiny little 12 second max
>voice chip module. Less than a square inch....but imagine the tons of
>mischief one can do with it....Or helpful warnings.
>
>And who says electronics isn't fun!
Eric, drink two beers, get a good night's rest and call me in
the morning :-)
Actually there are a number of aircraft and other vehicles where
voice annunciation is found appropriate . . . you'd want a VERY
distinct voice so that it doesn't go unnoticed amongst the chatter
on approach control. Hmmm . . . how about Jerry Lewis? Shucks, I've
got one of those stand-out voices. I'll record your phrases for
you at no charge!
Bob . . .
Message 14
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| Subject: | Re: 02/07/05 A Forced Landing |
--> AeroElectric-List message posted by: Dj Merrill <deej@thayer.dartmouth.edu>
Robert L. Nuckolls, III wrote:
> Shucks, I've got one of those stand-out voices. I'll record your phrases for
> you at no charge!
smoke detector in the shop:
"I said connect the black wire to GROUND, dummy!"
*grin*
-Dj
--
Dj Merrill
deej@thayer.dartmouth.edu
"TSA: Totally Screwing Aviation"
Message 15
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| Subject: | Re: 02/07/05 A Forced Landing |
--> AeroElectric-List message posted by: "Terry Watson" <terry@tcwatson.com>
A few years ago on the RV list, there was a discussion about audio warnings.
A very bright engineer working on an integrated avionics package for
experimental aircraft here in the Seattle area mentioned that his neighbor
was the actor who played the flight engineer on the original Star Trek
program. Was his name Scotty? It was great fun listening to the various
possible "reports from the engine room" that they were going to get him to
record as voice alarms.
Sadly, neither the engineer nor the actor is with us anymore. But good
ideas live on.
Terry
Do not archive
>
>Flashing lights, buzzers, horns and beepers......reminds me of Three Mile
>Island. I'm still wondering how I can execute the proper sequence to save
my
>life when my electrical system goes down....Let's see flip this switch up,
>pull this, cutoff that....call Bob.....
>
>It is now reasonably trivial to have voice warnings. One of the toys in the
>box of prototypes (I'll get to it soon.....) is a tiny little 12 second max
>voice chip module. Less than a square inch....but imagine the tons of
>mischief one can do with it....Or helpful warnings.
>
>And who says electronics isn't fun!
Eric, drink two beers, get a good night's rest and call me in
the morning :-)
Actually there are a number of aircraft and other vehicles where
voice annunciation is found appropriate . . . you'd want a VERY
distinct voice so that it doesn't go unnoticed amongst the chatter
on approach control. Hmmm . . . how about Jerry Lewis? Shucks, I've
got one of those stand-out voices. I'll record your phrases for
you at no charge!
Bob . . .
Message 16
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| Subject: | Re: 02/07/05 A Forced Landing |
--> AeroElectric-List message posted by: Dj Merrill <deej@thayer.dartmouth.edu>
Terry Watson wrote:
> Sadly, neither the engineer nor the actor is with us anymore. But good
> ideas live on.
Hi Terry,
The actor that played Scotty is James Doohan.
He is still alive, although not doing well.
He has Alzheimer's disease and also suffers from Parkinson's disease,
diabetes and lung fibrosis. I believe his last public
appearance was 31 Aug, 2004. If someone has more current
info, please share.
http://www.sfgate.com/cgi-bin/article.cgi?file=/news/archive/2004/08/31/state1830EDT0111.DTL
-Dj
--
Dj Merrill
deej@thayer.dartmouth.edu
"TSA: Totally Screwing Aviation"
Message 17
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| Subject: | Re: 02/07/05 A Forced Landing |
--> AeroElectric-List message posted by: "Terry Watson" <terry@tcwatson.com>
Sorry. It's very bad form to prematurely report someone's death. As Mark
Twain said, the reports of his death were greatly exaggerated.
Terry
Do not archive
-----Original Message-----
From: owner-aeroelectric-list-server@matronics.com
[mailto:owner-aeroelectric-list-server@matronics.com]On Behalf Of Dj Merrill
Subject: Re: AeroElectric-List: Re: 02/07/05 A Forced Landing
--> AeroElectric-List message posted by: Dj Merrill
<deej@thayer.dartmouth.edu>
Terry Watson wrote:
> Sadly, neither the engineer nor the actor is with us anymore. But good
> ideas live on.
Hi Terry,
The actor that played Scotty is James Doohan.
He is still alive, although not doing well.
He has Alzheimer's disease and also suffers from Parkinson's disease,
diabetes and lung fibrosis. I believe his last public
appearance was 31 Aug, 2004. If someone has more current
info, please share.
http://www.sfgate.com/cgi-bin/article.cgi?file=/news/archive/2004/08/31/stat
e1830EDT0111.DTL
-Dj
--
Dj Merrill
deej@thayer.dartmouth.edu
"TSA: Totally Screwing Aviation"
Message 18
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--> AeroElectric-List message posted by: "Mike Gregory" <m.j.gregory@talk21.com>
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III"
<rnuckolls@aeroelectric.com>
At 01:36 PM 8/19/2004 -0400, you wrote:
>Let's say that the capacitor needs to support the 2A drain for 100
milliseconds. Okay 2 volts delta, 2A, .1 seconds.
>I/C = V/S
>2/C = 2/.1
>2/C = 20
>C = 10 Farads
No! C = 0.1 Farad
>Hmmm . . . that's a pretty fat capacitor. Impossible to consider a few
years ago but in the realm of possibilities now. If we were supporting a
shorter
duration of brown-out, say 10 milliseconds, then a 1 Farad capacitor gets us
by. You see how this works?
You would now only need 10,000 microfarads. Assuming you were using an
aluminium electrolytic capacitor, this would be readily available at a 25 V
rating in a can 55 mm long by 40 mm dia.
>For the most part, a small battery can masquerade as a capacitor that is
physically much larger in size and weight. As a general rule, the brown-out
battery is a better choice from the perspective of sized and weight.
> I've used capacitors for this very task but at much lower currents where
perhaps 1,000 microfarads will do the trick.
>Bob . . .
I don't know if you need to worry about protecting the battery from
discharge when the unit is switched off - presumably switching can be
arranged to prevent this. I suspect the capacitor would be the better
solution as it would not need such switching and should last the life of the
installation. I suggest an experiment to see if 10,000 microfarads would
prevent a brownout, increasing to 22,000, 33,000 or 47,000 if necessary
until achieving a satisfactory result.
Best regards
Mike
Message 19
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| Subject: | 2-10 switched fuel pump |
--> AeroElectric-List message posted by: TimRhod@aol.com
Hi Bob I was reading in past articles that you recommended a 2-10 switch
for wiring a dukes fuel pump in the configuration of off- low- high. I have
the switch and in trying to figure it out the only way I can see to get high
is to also have low on at the same time. Is this correct? Any harm to the
pump to power both high and low wires together? Thanks Tim
Message 20
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| Subject: | Re: 02/07/05 A Forced Landing |
--> AeroElectric-List message posted by: "Tom Brusehaver" <cozytom@mn.rr.com>
I was originally thinking, yea, blinking lights might be more
of a problem than help, could be the FAA folks were thinking.
Then I went to work, started reading the spec's for some new
FAA software I am working on, and holy cow! talk about blinking.
It is their CHI (Computer Human Interface) spec, and they
got all kinds of stuff blinking, and at different rates! You
do a hand off from your sector to another sector, it blinks
the datablock at one rate. A flight is transitioning your sector
to an airport to land, but is controlled by another controller, the
datablock blinks at another rate. It seems everything has a
possible different rate (configurable software).
Then thinking about audio alerts. We had a controller tell us
about a cessna 337 that landed gear up a couple years ago. The
controller called 'em several times on the radio, "your gear
is up, go around". After they ground to a stop, the controller
got a chance to talk to the pilot, "didn't you hear me tell
you your gear is up?". "We couldn't hear nothing, there was
a loud buzzer going off".
> --> AeroElectric-List message posted by: Ken <klehman@albedo.net>
>
> Sounds like silly FAA deskjockey talk to me! I agree that status
> indicators should not flash but warning and caution lights?
> Surely nobody ignores a flashing light until explaining it. Removing a
> faulted flickering light bulb on extremely rare occasion is trivial.
> Flickering is not likely to be confused with flashing anyway. A
> light that isn't noticed is useless.
> Ken
>
Message 21
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| Subject: | Fuseable Link question |
--> AeroElectric-List message posted by: Charlie Kuss <chaztuna@adelphia.net>
Bob & Listers,
If I understand Bob's book correctly, Bob feels that any bus supply wire
which is 6" long or less, does not need circuit protection. I can not get
my main bus power supply wire that short (minimum bend radius and
obstruction considerations).
My main power supply circuit will go through a LittelFuse, 60 amp maxi
fuse and holder. However, I must run a 6AWG wire about 9" to reach this
fuse holder. Should I make a 10AWG fuseable link? This wire will be in free
air. It will be the supply line to both my main bus power and to the
alternator B lead. Or should I simply run 6 AWG wire to the fuse holder
without concern for a possible short in this 9" supply wire? If I use a 10
AWG wire (fuseable link), I can reduce this distance from 9" to 7". Since
this is the supply wire for my main bus, I'm concerned about voltage drop
here. Am I making mountains out of mole hills? How much of a
voltage/efficiency loss would be taken by installing the fuse able link?
Charlie Kuss
RV-8A
Message 22
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| Subject: | Re: 02/07/05 A Forced Landing |
--> AeroElectric-List message posted by: Richard Riley <Richard@Riley.net>
>A few years ago on the RV list, there was a discussion about audio warnings.
>A very bright engineer working on an integrated avionics package for
>experimental aircraft here in the Seattle area mentioned that his neighbor
>was the actor who played the flight engineer on the original Star Trek
>program. Was his name Scotty? It was great fun listening to the various
>possible "reports from the engine room" that they were going to get him to
>record as voice alarms.
About 10 years ago Majel Barette - Gene Roddenberry's wife and the voice of
the computer on Star Trek - The Next Generation, among other things -
agreed to record a series of audio warnings for me. A few days later our
prototype crashed and we never did it.
That was shortly after we did a missing man formation for Gene's memorial
service with Long EZ's, but that's another story.
Message 23
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| Subject: | Corbalis' Buzzer |
--> AeroElectric-List message posted by: Speedy11@aol.com
Leo,
Sounds like a good design you have. Do you have a means to mute the buzzer
once it has your attention? Does it start buzzing when you apply electrical
power and stop once you get the engine running?
Stan Sutterfield
Tampa
www.rv-8a.net
In a message dated 2/18/2005 2:57:36 AM Eastern Standard Time,
aeroelectric-list-digest@matronics.com writes:
When I built my Zodiac 601 HDS I put in a GRT engine monitor. The blinking
light from no oil pressure was supposed to remind me turn off the battery
switch. After the second flight, parked facing the late afternoon sun on the
ramp, I missed the light and ran the battery totally flat. I put a simple 2
1/2 or 3 inch Radio Shack buzzer in paralell with the light. The light has a
blinker circuit so just get a simple steady tone one. The buzzer is stuck to
the back side of the panel with 3M double sided foam tape. Its been there 7
years.
The buzzer is loud enough to hear clearly at full power thru my Peltor 7000
passive headset. The tone is probably higher than the ANR headsets try to
cancel.
Message 24
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| Subject: | Re: 2-10 switched fuel pump |
--> AeroElectric-List message posted by: "John Schroeder" <jschroeder@perigee.net>
Tim -
I have a wiring diagram for this. Attached is a .pdf. The color scheme is
a bit weird for now. We are using green to show a wire is installed. Let
me know if you have any questions or comments. I wired this on the panel
yesterday.
Ooops, I forgot about no attachments to this list. I'll email it directly.
Cheers,
John
On Fri, 18 Feb 2005 19:42:03 EST, <TimRhod@aol.com> wrote:
> --> AeroElectric-List message posted by: TimRhod@aol.com
>
> Hi Bob I was reading in past articles that you recommended a 2-10
> switch
> for wiring a dukes fuel pump in the configuration of off- low- high. I
> have
> the switch and in trying to figure it out the only way I can see to get
> high
> is to also have low on at the same time. Is this correct? Any harm
> to the
> pump to power both high and low wires together? Thanks Tim
>
>
--
Message 25
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| Subject: | Re: 02/07/05 A Forced Landing |
--> AeroElectric-List message posted by: Fiveonepw@aol.com
In a message dated 02/18/2005 7:02:44 PM Central Standard Time,
cozytom@mn.rr.com writes:
I was originally thinking, yea, blinking lights might be more
of a problem than help, could be the FAA folks were thinking.
>>>
I've got an LED annunciator dead-nuts centered in front of me as high on the
panel as practical that B L I N K S when my EIS4000 engine monitor
encounters some out-of-programmed- parameter "issue" and I've NEVER missed a
call- I almost look forward to the 30 minute reminders to check fuel status.
Plus it comes on solid when my Aeroelectric LVWM sees something it doesn't like,
the oil pressure craps, the flaps aren't all the way up, the canopy isn't
latched or either fuel tank is down by 2/3's. Works just fine and have never
missed anything the stupid thing is telling me, day or nite- what could be
simpler? I'm also wired for audio alerts but not active on this yet, and STILL
haven't missed any alarms.... I'm sorry, but the dark-n-stormy story of our
comrade in Canada just reinforces everything I've learned here on the A-list- If
my
all-electric-on-a-budget airplane ever falls from the sky because of an
electrical issue, it's because I probably climbed out of the cockpit, reached
through the oil door, ripped the battery from it's moorings and tossed the damn
thing overboard!
Sorry for preaching to the choir, but this RV driver is one happy camper when
it comes to shoving electrons around an airframe!
From The PossumWorks in TN, confirmed Nuckollhead:
Mark Phillips
Message 26
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--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <b.nuckolls@cox.net>
At 11:57 PM 2/18/2005 +0000, you wrote:
>--> AeroElectric-List message posted by: "Mike Gregory"
><m.j.gregory@talk21.com>
>
>--> AeroElectric-List message posted by: "Robert L. Nuckolls, III"
><rnuckolls@aeroelectric.com>
>
>At 01:36 PM 8/19/2004 -0400, you wrote:
>
> >Let's say that the capacitor needs to support the 2A drain for 100
>milliseconds. Okay 2 volts delta, 2A, .1 seconds.
>
> >I/C = V/S
>
> >2/C = 2/.1
>
> >2/C = 20
>
> >C = 10 Farads
>
>No! C = 0.1 Farad
Very good! Damn! My teachers told me to watch those transpositions.
> >Hmmm . . . that's a pretty fat capacitor. Impossible to consider a few
>years ago but in the realm of possibilities now. If we were supporting a
>shorter
>duration of brown-out, say 10 milliseconds, then a 1 Farad capacitor gets us
>by. You see how this works?
>
>You would now only need 10,000 microfarads. Assuming you were using an
>aluminium electrolytic capacitor, this would be readily available at a 25 V
>rating in a can 55 mm long by 40 mm dia.
>
> >For the most part, a small battery can masquerade as a capacitor that is
>physically much larger in size and weight. As a general rule, the brown-out
>battery is a better choice from the perspective of sized and weight.
>
> > I've used capacitors for this very task but at much lower currents where
>perhaps 1,000 microfarads will do the trick.
>
> >Bob . . .
>
>I don't know if you need to worry about protecting the battery from
>discharge when the unit is switched off - presumably switching can be
>arranged to prevent this. I suspect the capacitor would be the better
>solution as it would not need such switching and should last the life of the
>installation. I suggest an experiment to see if 10,000 microfarads would
>prevent a brownout, increasing to 22,000, 33,000 or 47,000 if necessary
>until achieving a satisfactory result.
Good catch Mike. Yes, depending on a variety of variables,
there may be opportunities to press the lowly capacitor into
service as a temporary battery.
Keep an eye on that grey-bearded ol' fart back in Spamcanville.
He's got one foot in a bucket, another in the fire . . . but
he DID quit picking up the wrong end of a soldering iron
years ago.
Bob . . .
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