Today's Message Index:
----------------------
1. 05:41 AM - Re: Dual alt single battery setup (Robert L. Nuckolls, III)
2. 05:42 AM - Re: E bus switching. (Robert L. Nuckolls, III)
3. 06:28 AM - Re: Dual alt single battery setup (f1rocket@comcast.net)
4. 06:41 AM - Re: Dual alt single battery setup (sjhdcl@kingston.net)
5. 07:05 AM - Many a good man....... (Fergus Kyle)
6. 07:55 AM - Re: Dual alt single battery setup (Robert L. Nuckolls, III)
7. 03:13 PM - Re: E bus switching. (David Carter)
8. 05:52 PM - High Current Switch or Battery Contactor (D Fritz)
9. 06:05 PM - Re: High Current Switch or Battery Contactor (DonVS)
10. 06:12 PM - Re: High Current Switch or Battery Contactor (Denis Walsh)
11. 06:41 PM - Re: High Current Switch or Battery Contactor (Robert L. Nuckolls, III)
Message 1
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| Subject: | Re: Dual alt single battery setup |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <b.nuckolls@cox.net>
At 08:56 PM 12/6/2004 -0500, you wrote:
>--> AeroElectric-List message posted by: "Steve & Denise"
><sjhdcl@kingston.net>
>
>I have another question for the group.
>
>I'm planning a single battery dual alternator setup. I'm planning to fly to
>some very
>remote airports in northern Canada and an alternator failure is a bad day.
>
>With reference to the Z diagram for dual alternator system I have a few
>questions.
I presume you're talking about Z-12.
>In normal flight the aux alternator is off. If the field switch is off does
>the voltage lamp still work.
Yes
>In other words if the backup alt fails for some reason and the
>main alt fails, would the aux alt voltage lamp come on still?
Not for the aux alternator. If your using Z-12 then the aux
alternator regulator is DIFFERENT than for the main alternator.
It's light says "AUX ALTERNATOR LOADED" meaning that if you
set it up according to instructions, then the aux alternator
automatically switches on when the main alternator fails and
assuming that total loads are within capability of the aux
alternator, the LOW VOLTS light would never come on . . . hence
the need to annunciate main alternator failure.
>Is there any reasons the have the backup alt on even though the main alt is
>functioning properly?
If you want the auto-switch feature yes. If you want to manually
switch the aux alternator on, no. The recommended operating
procedure is to run it ON all the time for a Z-12 system.
>With respect to how this system works. Suppose the main alternator fails,
>the backup alt is
>turned on, main alt turned off, and continue on flying. The backup alt is
>powering the main
>power bus. However I have now gone from 60A capability to 20A capability. I
>start conserving
>power by turning off the none essentials. My question is this:
>There are several items on the main power bus such as fuel senders, trim
>indicators, etc that
>can not be switched off. Should item like this have a small switch somewhere
>so they can
>be turned off to conserve power?
The very first thing you need to do in configuring your electrcial
system is a load analysis. KNOW what each piece of equipment draws
in normal flight and PLAN which items will be shut down to stay within
limits of your auxiliary alternator. The aux alternator warning light
will flash if you've overloaded the alternator. So if the main alternator
fails and the light comes on, you can either turn off things according to
a plan, or conduct an in-flight experiment to determine how many things
need to be off to stop the light from flashing . . . I'd recommend the
former.
>If the backup alt fails as well then the same process as mentioned a few
>days ago. Alt off,
>battery master off and now running on battery power alone to the essential
>bus.
yes . . . but this is about as likely as wing bolts coming loose.
>Why does the backup alt power the main battery bus and not the essential bus
>exclusively?
because Z-12 was designed to illustrate a means for adding
a second alternator to an existing system and in particular,
spam cans. Getting the #2 alternator blessed was agonizing enough,
re-shaping the architecture to add an e-bus was too much to
contemplate. If one chooses to have a robust backup like the
SD-20, then Figure Z-14 with no e-bus is recommended.
Are you sure you NEED 20A of backup for endurance? Can't you
get en-route running loads below 10A so that approach to landing
has the battery in 100% state of charge for the approach?
This is why I emphasize the load analysis and PLANS for each
contingency. I believe many builders are spending too much
money on hardware and adding pounds that do not materially
add value to the airplane.
Keep in mind folks that a belt-driven ND alternator is already
10X better than the piece-o-crap alternators bolted to most
spam cans. Doing preventative maintenance to insure minimal
battery capacity boosts probability for comfortable termination
of flight another 10X. Adding the e-bus puts yet another
multiplier on it. So, without having to make the system any
more complex than Figure Z-11, it is unlikely that any OBAM
aircraft will feature in an electrical system driven, dark-n-stormy
night story. Adding an SD-8 per Figure Z-13 should cover 98% of
all OBAM aircraft requirements for extended en-route operations
sans main alternator.
But if you don't do a load analysis or don't understand the
reasons for considering one architecture over another, then
you'll find yourself participating in threads like this
one and making decisions the democratic way . . . whatever
the majority of folks recommend. If that's the most comfortable
way to configure your project, fine. But I'd much rather you
get to the final configuration and operating philosophy by
understanding how all of the simple-ideas available to you
fit together. You'll find that you don't need backups, to backups
on top of more backups. You'll save dollars and time. Your
airplane will be lighter and simpler to operate. The spam-can
drivers can only dream of the advantages offered to the
OBAM aircraft pilot.
Bob . . .
Message 2
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| Subject: | Re: E bus switching. |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <b.nuckolls@cox.net>
At 08:52 PM 12/6/2004 -0600, you wrote:
>--> AeroElectric-List message posted by: "David Carter"
><dcarter@datarecall.net>
>
>Without the switch, the E-bus becomes a larger branch of a/the "battery
>bus". The switch would provide an easy way to save the battery by turning
>off all the stuff (radios) on the e-bus for 15' at a time. Of couse, could
>just turn off individual e-bus items instead of having an e-bus sw (to shut
>off the entire bus).
>
>With switch left on all the time, or with no switch at all, the diode would
>stop flow to "main bus" when master switch ("main bus" switch?) was turned
>off following alternator failure. Or, diode - and wire between main bus &
>e-bus - could be eliminated for reduced parts count.
. . . and your battery would run down while the airplane is parked.
Further, you would have no way to take the electrical system
to a max-cold condition in an approach to the rocks.
Bob . . .
Message 3
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| Subject: | Re: Dual alt single battery setup |
--> AeroElectric-List message posted by: f1rocket@comcast.net
Steve,
I went with a dual alternator, one battery system with an essential bus, although
I call it an avionics bus. In doing an analysis of the various offerings,
I found this arrangement to best fit my intended flight operations. I don't necessarily
agree that it adds additional weight. It is marginally more complex
to wire because you need the controller, switch, and breaker, but it's not that
bad. I actually think it's lighter than having a dual battery system especially
if your batteries are in the back. If you need the redundancy, I think
this is a good way to go.
My auxiliary alternator is on all the time. I like the convenience of it just
picking up the load should the main alternator fail. While I believe the B&C
alternators are way better than the automotive junk, I'm willing to pay extra
for the piece of mind that any flight can be continued unabated in the event of
alternator failure. Relying on a battery to carry the load is one way to achieve
this, having a backup alternator in another way. I simply prefer the later.
I also like having the avionics bus switchable from the main bus. I know all the
arguments against the avionics bus (I've been on the List for about 8 years),
but it is convenient to fire it up on the gound to get my clearance and my
radios/autopilot/EFIS are on all the time for every flight so one switch brings
up all the electronic goddies right where I left them. The fact that some manufacturers
recommend protecting their equipment from the phantom "spike" doesn't
prove that they exist, but it sure does void the warranty of some pretty
expensive equipment.
Study the options and pick the one that fits your intended use. I think they all
have a role to play.
Randy
F1 Rocket
http://f1rocket.home.comcast.net/
Steve,
I went with a dual alternator, one battery system with an essential bus, although
I call it an avionics bus. In doing an analysis of the various offerings, I
found this arrangement to best fit my intended flight operations. I don't necessarily
agree that it adds additional weight. It is marginally more complex to
wire because you need the controller, switch, and breaker, but it's not that
bad. I actually think it's lighter than having a dual battery system especially
if your batteries are in the back. If you need the redundancy, I think this
is a good way to go.
My auxiliary alternator is on all the time. I like the convenience of it just picking
up the load should the main alternator fail. While I believe the BC alternators
are way better than the automotive junk, I'm willing to pay extra for
the piece of mind that any flight can be continued unabated in the event of alternator
failure. Relying on a battery to carry the load is one way to achieve
this, having a backup alternator in another way. I simply prefer the later.
I also like having the avionics bus switchable from the main bus. I know all the
arguments against the avionics bus (I've been on the List for about 8 years),
but it is convenient to fire it up on the gound to get my clearance and my radios/autopilot/EFIS
are on all the time for every flight so one switch brings
up all the electronic goddies right where I left them. The fact that some manufacturers
recommend protecting their equipment from the phantom "spike" doesn't
prove that they exist, but it sure does void the warranty of some pretty expensive
equipment.
Study the options and pick the one that fits your intended use. I think they all
have a role to play.
Randy
F1 Rocket
http://f1rocket.home.comcast.net/
Message 4
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| Subject: | Re: Dual alt single battery setup |
--> AeroElectric-List message posted by: sjhdcl@kingston.net
I will definitely do a load analyisis and I do have a plan in the event of
alt failure and loads. I do not have all the avionics and equipment yet
and I've learned that measured the required current of each component is
far more accurate then asking the manufacturer.
I do have questions about the SD-8 however. I did consider this in the
beginning and of course the answer will lie in the load analysis as well.
But according the B&C publications the alterator is capable of about 6.8
amps during normal cruise engine RPM settings. While this is still enough
to 'limp' home if I get into icing conditions and turn the pitot heat on,
the alt will be overloaded. I know all these scenarios are very unlikely
but the planned mission for this aircraft does require extended fuel and
'electron' range. The 20A alt os much bigger and heavier. Not to mention
the additional $240 for the reg. I'm not a dark a story night kind of guy.
Most of those stories have nothing to do with the actual causes of the
incident.
On a previous homebuilt I was able to get the load down to about 2 amps on
'limp' mode. Running a wing leveler and GPS. It was only a test but it is
quite feasible to run a very low load and still get home safely. Once I
got close to the airport, I turned the radio, transponder, VOR/ILS,
landing lights, flap power, etc back on and was running 16A for the
approach phase which lasted only about 15 minutes.
Thanks for the great information and the push back to the SD-8 alternator.
Much lighter and cheaper. I will verify the load analysis in modes and
post my findings in the months to come.
Great answer,
Steve
RV7A
> --> AeroElectric-List message posted by: "Robert L. Nuckolls, III"
> <b.nuckolls@cox.net>
>
> At 08:56 PM 12/6/2004 -0500, you wrote:
>>--> AeroElectric-List message posted by: "Steve & Denise"
>><sjhdcl@kingston.net>
>>
>>I have another question for the group.
>>
>>I'm planning a single battery dual alternator setup. I'm planning to fly
>> to
>>some very
>>remote airports in northern Canada and an alternator failure is a bad
>> day.
>>
>>With reference to the Z diagram for dual alternator system I have a few
>>questions.
>
> I presume you're talking about Z-12.
>
>
>>In normal flight the aux alternator is off. If the field switch is off
>> does
>>the voltage lamp still work.
>
> Yes
>
>
>>In other words if the backup alt fails for some reason and the
>>main alt fails, would the aux alt voltage lamp come on still?
>
> Not for the aux alternator. If your using Z-12 then the aux
> alternator regulator is DIFFERENT than for the main alternator.
> It's light says "AUX ALTERNATOR LOADED" meaning that if you
> set it up according to instructions, then the aux alternator
> automatically switches on when the main alternator fails and
> assuming that total loads are within capability of the aux
> alternator, the LOW VOLTS light would never come on . . . hence
> the need to annunciate main alternator failure.
>
>
>>Is there any reasons the have the backup alt on even though the main alt
>> is
>>functioning properly?
>
>
> If you want the auto-switch feature yes. If you want to manually
> switch the aux alternator on, no. The recommended operating
> procedure is to run it ON all the time for a Z-12 system.
>
>
>>With respect to how this system works. Suppose the main alternator fails,
>>the backup alt is
>>turned on, main alt turned off, and continue on flying. The backup alt is
>>powering the main
>>power bus. However I have now gone from 60A capability to 20A capability.
>> I
>>start conserving
>>power by turning off the none essentials. My question is this:
>>There are several items on the main power bus such as fuel senders, trim
>>indicators, etc that
>>can not be switched off. Should item like this have a small switch
>> somewhere
>>so they can
>>be turned off to conserve power?
>
> The very first thing you need to do in configuring your electrcial
> system is a load analysis. KNOW what each piece of equipment draws
> in normal flight and PLAN which items will be shut down to stay within
> limits of your auxiliary alternator. The aux alternator warning light
> will flash if you've overloaded the alternator. So if the main
> alternator
> fails and the light comes on, you can either turn off things according
> to
> a plan, or conduct an in-flight experiment to determine how many
> things
> need to be off to stop the light from flashing . . . I'd recommend the
> former.
>
>
>>If the backup alt fails as well then the same process as mentioned a few
>>days ago. Alt off,
>>battery master off and now running on battery power alone to the
>> essential
>>bus.
>
> yes . . . but this is about as likely as wing bolts coming loose.
>
>
>>Why does the backup alt power the main battery bus and not the essential
>> bus
>>exclusively?
>
> because Z-12 was designed to illustrate a means for adding
> a second alternator to an existing system and in particular,
> spam cans. Getting the #2 alternator blessed was agonizing enough,
> re-shaping the architecture to add an e-bus was too much to
> contemplate. If one chooses to have a robust backup like the
> SD-20, then Figure Z-14 with no e-bus is recommended.
>
> Are you sure you NEED 20A of backup for endurance? Can't you
> get en-route running loads below 10A so that approach to landing
> has the battery in 100% state of charge for the approach?
> This is why I emphasize the load analysis and PLANS for each
> contingency. I believe many builders are spending too much
> money on hardware and adding pounds that do not materially
> add value to the airplane.
>
> Keep in mind folks that a belt-driven ND alternator is already
> 10X better than the piece-o-crap alternators bolted to most
> spam cans. Doing preventative maintenance to insure minimal
> battery capacity boosts probability for comfortable termination
> of flight another 10X. Adding the e-bus puts yet another
> multiplier on it. So, without having to make the system any
> more complex than Figure Z-11, it is unlikely that any OBAM
> aircraft will feature in an electrical system driven, dark-n-stormy
> night story. Adding an SD-8 per Figure Z-13 should cover 98% of
> all OBAM aircraft requirements for extended en-route operations
> sans main alternator.
>
> But if you don't do a load analysis or don't understand the
> reasons for considering one architecture over another, then
> you'll find yourself participating in threads like this
> one and making decisions the democratic way . . . whatever
> the majority of folks recommend. If that's the most comfortable
> way to configure your project, fine. But I'd much rather you
> get to the final configuration and operating philosophy by
> understanding how all of the simple-ideas available to you
> fit together. You'll find that you don't need backups, to backups
> on top of more backups. You'll save dollars and time. Your
> airplane will be lighter and simpler to operate. The spam-can
> drivers can only dream of the advantages offered to the
> OBAM aircraft pilot.
>
> Bob . . .
>
>
Message 5
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| Subject: | Many a good man....... |
--> AeroElectric-List message posted by: "Fergus Kyle" <VE3LVO@rac.ca>
Time: 07:53:26 AM PST US
From: "Bryan Hooks" <bryanhooks@comcast.net>
Subject: RE: AeroElectric-List: fuse block location
--> AeroElectric-List message posted by: "Bryan Hooks"
<bryanhooks@comcast.net>
I recently had one blow in my wifes' SUV. Not quite sure why though.
All she did was plug an inverter into the cig lighter, plug a hair dryer
into that and turned it on. :)
On an unfortunate note, she didn't quite have enough time to get her
hair dry before the fuse had blown.
I now have the inverter put up out of her reach, so to speak since it
apparently is my fault for not telling her not to plug her hair dryer
into it.
-bryan
Thank you, Brian.......... After having flown crew and pax for some years I
remember the same script for the stews who would always complain about the
loss of the 'ground' circuit on the leg outbound to some coral reef. The
ground circuit was for vacuum cleaners and so forth.
You guessed it . So I would explain that it comes back to life by
resetting by a qualified mechanic at home base. Fortunately most coral reefs
(etc) used 220Vac/50cycle and so did not tip my hand.
The scenario complicates when one stew is married to the First Officer.
Pillow talk has destroyed many an aviator.
Ferg
Europa 064
Message 6
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| Subject: | Re: Dual alt single battery setup |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <b.nuckolls@cox.net>
At 09:41 AM 12/7/2004 -0500, you wrote:
>--> AeroElectric-List message posted by: sjhdcl@kingston.net
>
>I will definitely do a load analyisis and I do have a plan in the event of
>alt failure and loads. I do not have all the avionics and equipment yet
>and I've learned that measured the required current of each component is
>far more accurate then asking the manufacturer.
>
>I do have questions about the SD-8 however. I did consider this in the
>beginning and of course the answer will lie in the load analysis as well.
>But according the B&C publications the alterator is capable of about 6.8
>amps during normal cruise engine RPM settings.
If you cruise at 2300, that is the rated output assuming a 1.3:1 step
up ratio for the vacuum pump pad.
> While this is still enough
>to 'limp' home if I get into icing conditions and turn the pitot heat on,
>the alt will be overloaded.
Yes . . . but this is when you do the prudent 180 and depart icing
conditions.
> I know all these scenarios are very unlikely
>but the planned mission for this aircraft does require extended fuel and
>'electron' range. The 20A alt os much bigger and heavier. Not to mention
>the additional $240 for the reg.
and alternator is about $250 more expensive as well . . .
> I'm not a dark a story night kind of guy.
>Most of those stories have nothing to do with the actual causes of the
>incident.
>
>On a previous homebuilt I was able to get the load down to about 2 amps on
>'limp' mode. Running a wing leveler and GPS. It was only a test but it is
>quite feasible to run a very low load and still get home safely. Once I
>got close to the airport,
Which is exactly what the e-bus is for . . . minimal draw in the
en-route mode . . .
>I turned the radio, transponder, VOR/ILS,
>landing lights, flap power, etc back on and was running 16A for the
>approach phase which lasted only about 15 minutes.
which needed only 25% of your reserve capacity as long as it
wasn't tapped in the en-route mode.
>Thanks for the great information and the push back to the SD-8 alternator.
>Much lighter and cheaper. I will verify the load analysis in modes and
>post my findings in the months to come.
Good idea.
Bob . . .
Message 7
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| Subject: | Re: E bus switching. |
--> AeroElectric-List message posted by: "David Carter" <dcarter@datarecall.net>
Yikes! I did it again - forgot something I used to know! Thanks again, Bob,
for keeping us straight.
- It must be true that one must "learn and forget" something 3 to 5
times before it is indelibly impressed into one's memory. I'm getting close
to the upper limit!
David Carter
----- Original Message -----
From: "Robert L. Nuckolls, III" <b.nuckolls@cox.net>
Subject: Re: AeroElectric-List: E bus switching.
> --> AeroElectric-List message posted by: "Robert L. Nuckolls, III"
<b.nuckolls@cox.net>
>
> At 08:52 PM 12/6/2004 -0600, you wrote:
> >--> AeroElectric-List message posted by: "David Carter"
> ><dcarter@datarecall.net>
> >
> >Without the switch, the E-bus becomes a larger branch of a/the "battery
> >bus". The switch would provide an easy way to save the battery by
turning
> >off all the stuff (radios) on the e-bus for 15' at a time. Of couse,
could
> >just turn off individual e-bus items instead of having an e-bus sw (to
shut
> >off the entire bus).
> >
> >With switch left on all the time, or with no switch at all, the diode
would
> >stop flow to "main bus" when master switch ("main bus" switch?) was
turned
> >off following alternator failure. Or, diode - and wire between main bus
&
> >e-bus - could be eliminated for reduced parts count.
>
> . . . and your battery would run down while the airplane is parked.
> Further, you would have no way to take the electrical system
> to a max-cold condition in an approach to the rocks.
>
> Bob . . .
Message 8
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| Subject: | High Current Switch or Battery Contactor |
--> AeroElectric-List message posted by: D Fritz <dfritzj@yahoo.com>
Hey folks,
Here's an idea for those of you trying to keep current within a small budget.
Instead of using a battery contactor, why not use a high current switch like this
one:
http://www.mpja.com/directview.asp?product=8373-sw
Are there any regulations against using something like this instead of a contactor?
Are there any reasons why something like this doesn't make sense?
Dan Fritz
---------------------------------
Message 9
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| Subject: | High Current Switch or Battery Contactor |
--> AeroElectric-List message posted by: "DonVS" <dsvs@comcast.net>
This would require either the fat wire be brought into the cockpit or some
way of activating the switch would be needed.
-----Original Message-----
From: owner-aeroelectric-list-server@matronics.com
[mailto:owner-aeroelectric-list-server@matronics.com]On Behalf Of D
Fritz
Subject: AeroElectric-List: High Current Switch or Battery Contactor
--> AeroElectric-List message posted by: D Fritz <dfritzj@yahoo.com>
Hey folks,
Here's an idea for those of you trying to keep current within a small
budget. Instead of using a battery contactor, why not use a high current
switch like this one:
http://www.mpja.com/directview.asp?product=8373-sw
Are there any regulations against using something like this instead of a
contactor? Are there any reasons why something like this doesn't make
sense?
Dan Fritz
---------------------------------
Message 10
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| Subject: | Re: High Current Switch or Battery Contactor |
--> AeroElectric-List message posted by: Denis Walsh <denis.walsh@comcast.net>
I have been pondering this for years. My contactor uses the better
part of an amp, not to mention another fail mode. A few years ago I
saw something very like this on a Mooney so it is or was ok back then
with FAA. It was operated by a cable and lever.
The biggest down side I see is that it needs to be very close to the
battery for crash safety purposes. If you do this, then you need a
cable or lever to remotely operate it. This introduces what is
probably a bigger failure probability, and weight issues too.
So in the end, since the ones I found were just as heavy as the
solenoid, I stayed with the solenoid, which I think gets the nod on
parts count and simplicity for remote operation.
Post script. The only time the solenoid load is an issue for me is
when the alternator fails. In that case, the master contactor goes off
anyway and its function is replace with a low or no drain relay/switch.
Also it is a very reliable device, and lasts a long time, unlike its
starter contactor brethren, which gets heavier wear in use.
Interested in hearing other slants on this.
Denis
On Dec 7, 2004, at 6:49 PM, D Fritz wrote:
> --> AeroElectric-List message posted by: D Fritz <dfritzj@yahoo.com>
>
> Hey folks,
> Here's an idea for those of you trying to keep current within a small
> budget. Instead of using a battery contactor, why not use a high
> current switch like this one:
>
> http://www.mpja.com/directview.asp?product=8373-sw
>
> Are there any regulations against using something like this instead of
> a contactor? Are there any reasons why something like this doesn't
> make sense?
>
> Dan Fritz
>
>
> ---------------------------------
>
>
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| Subject: | Re: High Current Switch or Battery Contactor |
--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <b.nuckolls@cox.net>
At 05:49 PM 12/7/2004 -0800, you wrote:
>--> AeroElectric-List message posted by: D Fritz <dfritzj@yahoo.com>
>
>Hey folks,
>Here's an idea for those of you trying to keep current within a small
>budget. Instead of using a battery contactor, why not use a high current
>switch like this one:
>
>http://www.mpja.com/directview.asp?product=8373-sw
Sure. Lots of times. Smaller airplanes with rotax engines
needing remotely operated battery switches have modified
speed-shop battery switches to rotate by means of a fabricated
bellcrank operated by what is generically called a Bowden
control cable. These are used on gazillions of vehicles
including airplanes for remote control of chokes, heater
valves, carburetor heat doors, etc. etc.
You can purchase these cables from MANY sources but one
of my favorites is this choke conversion kit:
http://www.jcwhitney.com/autoparts/ProductDisplay/s-10101/p-2745/c-10101
The stock control cable for this kit is 60" long and the ad
alludes to a 108" version for trucks but no catalog number
is offered. At least folks MAKE very long versions of these
cables.
If you use one of these in your airplane . . . ESPECIALLY
if it's a long one, pull the control wire totally out of
the spiral shell and lubricate the wire with a good, sticky
grease like wheel bearing grease. They will come dry but
after 10 years in your airplane, operating friction will go
up risking malfunction. Design your system so that you PULL
the control to turn the battery OFF. If you fail the control,
it will be during preflight when you PUSH to turn the battery
ON and you won't go flying before you fix it.
What you don't want is to fail the control when you're
PUSHING on it in hopes that the battery is going to become
disconnected.
Consider this same technology for fabricating firewall
fuel shutoff valves. There are lots of low-cost ball-valves
with gasoline friendly seals that can be fitted with bellcranks
for operation with similar technology . . . again, PULL for
FUEL OFF.
>Are there any regulations against using something like this instead of a
>contactor? Are there any reasons why something like this doesn't make sense?
There are no regulations that pertain to the design and
installation of any system in your OBAM aircraft.
Bob . . .
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