AeroElectric-List Digest Archive

Sun 02/15/09


Total Messages Posted: 16



Today's Message Index:
----------------------
 
     1. 05:36 AM - Single Bus (h&jeuropa)
     2. 08:18 AM - Re: Anyway to test VOR antenna location on ground? (Paul McAllister)
     3. 10:04 AM - Re: Anyway to test VOR antenna location on ground? (Robert L. Nuckolls, III)
     4. 10:07 AM - Re: Single Bus (Robert L. Nuckolls, III)
     5. 11:12 AM - Re: Single Bus (bcollinsmn)
     6. 12:04 PM - Mode C Problem ()
     7. 12:35 PM - Re: Mode C Problem (Floyd)
     8. 12:53 PM - Re: Mode C Problem (Bill Hibbing)
     9. 01:44 PM - Re: AeroElectric-List Digest: 6 Msgs - 02/13/09 (John Markey)
    10. 02:09 PM - Re: Single Bus (cjay)
    11. 02:38 PM - Re: Mode C Problem (David LLoyd)
    12. 02:41 PM - Re: Re: Single Bus (Bob Collins)
    13. 03:34 PM - Re: Starting currents rusting the crankcase? (Robert L. Nuckolls, III)
    14. 04:33 PM - The future of avionics (bcollinsmn)
    15. 07:05 PM - Re: AeroElectric-List Digest: 9 Msgs - 02/14/09 (Speedy11@aol.com)
    16. 10:03 PM - System Objectives (westexflyboy)
 
 
 


Message 1


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    Time: 05:36:40 AM PST US
    Subject: Single Bus
    From: "h&amp;jeuropa" <butcher43@att.net>
    I am helping a friend with his electrical system. The aircraft is a Velocity, fixed landing gear. The equipment being installed is a pair of GRT EFIS, Garmin GNS430, GTX327 and GMA340 and LED lighting. Given that the EFIS provides prompt warning of electrical problems, we are wondering if an Essential Bus is really necessary. With the warning from the EFIS, electrical load can be shed quickly (turn off items and go to hand held radio & GPS, airspeed, alt & internal battery powered attitude). So we are considering a simple system like Fig 17-6 (or Z11 & Z30) without the Essential Bus features (he needs the weight of the batteries for CG reasons). Are we missing something here? Thanks Jim Butcher Europa XS N241BW Read this topic online here: http://forums.matronics.com/viewtopic.php?p=230316#230316


    Message 2


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    Time: 08:18:30 AM PST US
    From: Paul McAllister <l_luv2_fly@yahoo.com>
    Subject: Re: Anyway to test VOR antenna location on ground?
    Hi Ron, If I were to do it over again I would put mine in the wing, despite the acc ess issues and the need to have a co axial cable connection in the wing. I had mine in the floor and I had problems getting the localizer and glides lope.- I moved it to the roof and it improved but it wasn't great althoug h I find VOR reception perfect in that location. Obviously you will want to keep your strobe wires as far away as possible, but as you probably know, the coupling is an inverse relationship, so a lit tle bit of distance buys you a lot. My strobe is on top of the fin and the wire passes close to my Bob Archer c omm antenna with no ill effect. As to answering your question, no, sorry I don't know of anyway to test the relative merits of locations.- I think its one of those things that you ask around on and find out what has worked / not worked for them. As for me, my airplane is looking less and less like and airplane these day s.- The engine is out at LEAF (Rotax shop) to split the case and inspect. While the engine is off I am going to remove the flap drive tube as I am i nstalling electric flaps, move the oil tank in preparation for installing t he intercooler and I am going to do a phase one of my cooling modifications . I am not going to do all of my cooling mods or install the intercooler this time around, otherwise I will be all year getting it back in the air. Cheers, Paul=0A=0A=0A


    Message 3


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    Time: 10:04:46 AM PST US
    From: "Robert L. Nuckolls, III" <nuckolls.bob@aeroelectric.com>
    Subject: Re: Anyway to test VOR antenna location on ground?
    At 11:33 PM 2/14/2009, you wrote: >I have an AAE antenna for my panel mounted Vertex VX-700 handheld. I >made a 1/4" thick balsa 90 degree bracket where half the antenna is >horizontal, and half vertical so it will kinda work for both nav and >com (supposedly ~ 70% as well for each as compared to mounting with >antenna straight in proper orientation) > >Anyway had strobes going today (Kunzleman that drives two wingtip >heads with position LEDs) and found a location where the strobes >don't antagonize too much. This places the horizontal portion of the >antenna at the top of the fuse going fore and aft parallel with the >pitch torque tube ( large OD thin wall aluminium) about 16" away. > >Any ideas on how I could perhaps test VOR on ground to see if >location works reasonable? > >I tuned to a VOR and was just about able to hear identifier with >volume all the way up. No change to reception with antenna out of >plane or in position I like with strobe going, I spun plane 360 >degrees while listening and there was no change. Antennas for frequencies below that of transponders and GPS are almost always a compromise from "ideal". Ideal being a 1/4 wave radiator sitting in the center of an infinite ground plane and no metallic obstructions closer than say 10 wavelengths. Fortunately, the vast majority of our communications and navigation is line of sight limited and ground based transmitters in both services tend to be robust. Only a flight test in the situations YOU plan to use the antennas will let you know if "more study is needed". I've had builders report 100% satisfactory performance and others report "piece of @#$@#" performance on the same antenna. Problem was that one guy never talked to anyone outside a traffic pattern and the other guy was hoping for "loud and clear" from an RCO out on his 10,000 foot horizon. Every antenna installation on a $high$ TC aircraft where optimum performance is expected gets an in-flight pattern test. This takes a bunch of test equipment and a cooperating ground station. Our Mid-Continent airport is 10.5 miles from the VOR and I can recall very few radios that would get a signal strong enough on the ground but EVERY radio would come alive seconds after you broke ground. These were antennas and radios that are presumably holy-watered. So without a lot of $time$ and test equipment expense, your next best bet is go fly it. Bob . . . ----------------------------------------) ( . . . a long habit of not thinking ) ( a thing wrong, gives it a superficial ) ( appearance of being right . . . ) ( ) ( -Thomas Paine 1776- ) ----------------------------------------


    Message 4


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    Time: 10:07:12 AM PST US
    From: "Robert L. Nuckolls, III" <nuckolls.bob@aeroelectric.com>
    Subject: Re: Single Bus
    At 07:34 AM 2/15/2009, you wrote: > >I am helping a friend with his electrical system. The aircraft is a >Velocity, fixed landing gear. The equipment being installed is a >pair of GRT EFIS, Garmin GNS430, GTX327 and GMA340 and LED lighting. > >Given that the EFIS provides prompt warning of electrical problems, >we are wondering if an Essential Bus is really necessary. With the >warning from the EFIS, electrical load can be shed quickly (turn off >items and go to hand held radio & GPS, airspeed, alt & internal >battery powered attitude). > >So we are considering a simple system like Fig 17-6 (or Z11 & Z30) >without the Essential Bus features (he needs the weight of the >batteries for CG reasons). Are we missing something here? The E-bus is an ENDURANCE bus that not only congregates those items most useful for battery only en route continuation of flight that also provides dual power pathways. One of those pathways does not require a battery contactor to be closed (wasted energy equal to about 3 solid state receivers). Z-11 is no heavier than an off-the-ramp TC aircraft with an avionics bus. The E-bus is always recommended if you plan to venture of cross country . . . and particularly at night. Bob . . . ----------------------------------------) ( . . . a long habit of not thinking ) ( a thing wrong, gives it a superficial ) ( appearance of being right . . . ) ( ) ( -Thomas Paine 1776- ) ----------------------------------------


    Message 5


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    Time: 11:12:16 AM PST US
    Subject: Re: Single Bus
    From: "bcollinsmn" <bob@rvbuildershotline.com>
    [quote="nuckolls.bob(at)aeroelect"]At 07:34 AM 2/15/2009, you wrote: > > > Z-11 is no heavier than an off-the-ramp > TC aircraft with an avionics bus. The > E-bus is always recommended if you plan > to venture of cross country . . . and > particularly at night. > A few weeks ago I tried to get some feedback on approaching these things by way of the Vertical Power system. I didn't see any reaction to it. When I was at SteinAir a month or so ago for a Minnesota Wing (Van's Air Force) meeting, Stein pointed out that the solid state setup is the future of avionics. But I don't think I've ever seen this discussed on this board (which, by the way, I consider to be THE single most valuable bulletin board for homebuilders anywhere). It would be possible -- from what I can gather -- to set up a good backup system, but not without circuit breakers/fuses/switches, which defeats the purpose of the VP system. I'm just curious how you see this approach to aircraft wiring fitting into some of the excellent advice you provide wrt avionics and electrical system infrastructure? -------- Bob Collins St. Paul, Minn. RV-7A (#&amp;^ fiberglass!) http://rvbuildershotline.com Day job: http://minnesota.publicradio.org/collections/special/columns/news_cut/ Read this topic online here: http://forums.matronics.com/viewtopic.php?p=230372#230372


    Message 6


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    Time: 12:04:41 PM PST US
    From: <chasb@satx.rr.com>
    Subject: Mode C Problem
    Mode C problem My Mode C is intermittant and I cannot figure out why. I have an Apollo SL-70 transponder hooked to a Trans-Cal 120-30xx solid state encoder. The two are hooked together via an Approach Systems cable system. The mode C seems to work as advertised on the ground, but becomes more and more intermittant as the airplane goes to altitude. At altitude, the Mode C quits for a couple of minutes, works for a minute or so and continues to cycle at a variable rate. When the Mode C is transmitting at altitude, it sends correct altitude data. My static system is tight as confirmed by a pressure test that stays constant for nearly 30 minutes. The cable connections seem tight and wiggling the cable and other wires behind the panel has no effect on the Mode C operation on the ground. I had the same problem with an AmeriKing AK-350 encoder which was recently replaced by the new Trans-Cal encoder. I am beginning to suspect the SL-70 though the Garmin (formerly Apollo) folks insist the problem is with the encoder. Any suggestions would be appreciated. Charlie Brame RV-6A N11CB San Antonio


    Message 7


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    Time: 12:35:07 PM PST US
    From: "Floyd" <fwilkes@gvtc.com>
    Subject: Re: Mode C Problem
    Charle, If you are using grey code, it sounds like one of the pins at the transponder is bent. I had the exact same problem and it was a bent pin. If you are using serial, disreguard the above. If you need help, come see me, I am next hangar to Brian and Jim at Kestrel. Floyd Wilkes 601XL Do not archive ----- Original Message ----- From: <chasb@satx.rr.com> Sent: Sunday, February 15, 2009 1:58 PM Subject: AeroElectric-List: Mode C Problem > > Mode C problem > > My Mode C is intermittant and I cannot figure out why. > > I have an Apollo SL-70 transponder hooked to a Trans-Cal 120-30xx solid > state > encoder. The two are hooked together via an Approach Systems cable system. > The > mode C seems to work as advertised on the ground, but becomes more and > more > intermittant as the airplane goes to altitude. At altitude, the Mode C > quits for > a couple of minutes, works for a minute or so and continues to cycle at a > variable rate. When the Mode C is transmitting at altitude, it sends > correct > altitude data. My static system is tight as confirmed by a pressure test > that > stays constant for nearly 30 minutes. The cable connections seem tight and > wiggling the cable and other wires behind the panel has no effect on the > Mode C > operation on the ground. I had the same problem with an AmeriKing AK-350 > encoder > which was recently replaced by the new Trans-Cal encoder. > > I am beginning to suspect the SL-70 though the Garmin (formerly Apollo) > folks > insist the problem is with the encoder. > > Any suggestions would be appreciated. > > Charlie Brame > RV-6A N11CB > San Antonio > > >


    Message 8


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    Time: 12:53:11 PM PST US
    From: "Bill Hibbing" <n744bh@bellsouth.net>
    Subject: Re: Mode C Problem
    Charlie, I had a somewhat similar problem with my transponder and found out it was a bad finger in the tray connector. It caused me to pull my hair out finding it but when I looked closely at the connector with the transponder out I noticed one of the fingers in the connector didn't look quite right and when I checked with my avionics shop he looked at the pin readout and told me that that particular finger could certainly cause the problem I was having, which was the mode C was intermittently going way off altitude. Once I pulled out the connector and replaced that finger the problem was solved. Try pulling out your transponder and take a careful look at the tray connector. This may not be the problem but it's one more place you might look at. Bill, Glasair SIIS-FT ----- Original Message ----- From: <chasb@satx.rr.com> Sent: Sunday, February 15, 2009 1:58 PM Subject: AeroElectric-List: Mode C Problem > > Mode C problem > > My Mode C is intermittant and I cannot figure out why. > > I have an Apollo SL-70 transponder hooked to a Trans-Cal 120-30xx solid > state > encoder. The two are hooked together via an Approach Systems cable system. > The > mode C seems to work as advertised on the ground, but becomes more and > more > intermittant as the airplane goes to altitude. At altitude, the Mode C > quits for > a couple of minutes, works for a minute or so and continues to cycle at a > variable rate. When the Mode C is transmitting at altitude, it sends > correct > altitude data. My static system is tight as confirmed by a pressure test > that > stays constant for nearly 30 minutes. The cable connections seem tight and > wiggling the cable and other wires behind the panel has no effect on the > Mode C > operation on the ground. I had the same problem with an AmeriKing AK-350 > encoder > which was recently replaced by the new Trans-Cal encoder. > > I am beginning to suspect the SL-70 though the Garmin (formerly Apollo) > folks > insist the problem is with the encoder. > > Any suggestions would be appreciated. > > Charlie Brame > RV-6A N11CB > San Antonio > > -------------------------------------------------------------------------------- Checked by AVG - www.avg.com 18:01:00


    Message 9


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    Time: 01:44:28 PM PST US
    From: John Markey <markeypilot@yahoo.com>
    Subject: Re: AeroElectric-List Digest: 6 Msgs - 02/13/09
    My A&P mechanic told me to bolt the 2ga wire right next to the starter. Thi s asures the best ground dring the highest amp loading on this circuit. Als o, in some spam machines, it has been reported that electrogalvanic corrosi on was caused by forcing starter motor current to run through the block, et c. to a ground wire on the rear of the engine. Bob, comments from your experience? Glasair John III SMBCers of Chicago The intuitive mind is a sacred gift and the rational mind is a faithful se rvant. We have created a society that honors the servant and has forgotten the gift. -Albert Einstein. - ________________________________ Message 3 _____________________________________ Time: 07:51:51 AM PST US Subject: AeroElectric-List: Affixing an Engine Ground From: <longg@pjm.com> I have a new IO-360 and I am at a loss as to the best place to bolt the ground wire. Do any of you have a suggestion? A picture may be valuable here. Along the same lines, my craft is fiberglass and I am wondering if it's smart to have two such ground running from the firewall to the engine. Thanks, Glenn =0A=0A=0A


    Message 10


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    Time: 02:09:57 PM PST US
    Subject: Re: Single Bus
    From: "cjay" <cgfinney@yahoo.com>
    [quote="bcollinsmn"] nuckolls.bob(at)aeroelect wrote: > At 07:34 AM 2/15/2009, you wrote: > > A few weeks ago I tried to get some feedback on approaching these things by way of the Vertical Power system. I didn't see any reaction to it. > > When I was at SteinAir a month or so ago for a Minnesota Wing (Van's Air Force) meeting, Stein pointed out that the solid state setup is the future of avionics. > > But I don't think I've ever seen this discussed on this board (which, by the way, I consider to be THE single most valuable bulletin board for homebuilders anywhere). > > It would be possible -- from what I can gather -- to set up a good backup system, but not without circuit breakers/fuses/switches, which defeats the purpose of the VP system. > > I'm just curious how you see this approach to aircraft wiring fitting into some of the excellent advice you provide wrt avionics and electrical system infrastructure? Bob, VP recommends an endurance bus as well, same concept as outlined in Z11. Nothing magical about VP, it just replaces the breakers/fuses/switches with solid state technology. I think a lot of people are going to be cautious for awhile because everthing flows through a self contained box. This simplifies design and installation; but a bit of faith is required until people start getting comfortable with the concept. I think they've got a good track record so far. cjay Read this topic online here: http://forums.matronics.com/viewtopic.php?p=230397#230397


    Message 11


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    Time: 02:38:37 PM PST US
    From: "David LLoyd" <skywagon@charter.net>
    Subject: Re: Mode C Problem
    Is the transponder antenna "clean"....?, And well connected, grounded, etc. Engine oil can cause power emission troubles as it is a bit conductive at those high frequencies. D ----- Original Message ----- From: <chasb@satx.rr.com> Sent: Sunday, February 15, 2009 11:58 AM Subject: AeroElectric-List: Mode C Problem > > Mode C problem > > My Mode C is intermittant and I cannot figure out why. > > I have an Apollo SL-70 transponder hooked to a Trans-Cal 120-30xx solid > state > encoder. The two are hooked together via an Approach Systems cable system. > The > mode C seems to work as advertised on the ground, but becomes more and > more > intermittant as the airplane goes to altitude. At altitude, the Mode C > quits for > a couple of minutes, works for a minute or so and continues to cycle at a > variable rate. When the Mode C is transmitting at altitude, it sends > correct > altitude data. My static system is tight as confirmed by a pressure test > that > stays constant for nearly 30 minutes. The cable connections seem tight and > wiggling the cable and other wires behind the panel has no effect on the > Mode C > operation on the ground. I had the same problem with an AmeriKing AK-350 > encoder > which was recently replaced by the new Trans-Cal encoder. > > I am beginning to suspect the SL-70 though the Garmin (formerly Apollo) > folks > insist the problem is with the encoder. > > Any suggestions would be appreciated. > > Charlie Brame > RV-6A N11CB > San Antonio > > >


    Message 12


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    Time: 02:41:07 PM PST US
    From: "Bob Collins" <bcollinsrv7a@comcast.net>
    Subject: Re: Single Bus
    Are you sure, cjay? There is a "get home" backup system for the VP-100 and VP-200 http://verticalpower.com/docs/Backup_Wiring.pdf But Marc says he's not a fan of it because it introduces several failure points. And, of course, the VP-200 (and I think the VP-100, too) has its load-shedding ability configured into the unit itself. I have a VP-50, one alternator setup. I was trying to figure out how to get the same benefits that the system in Z-11 affords, but the only system I could come up with involved a second VP-50 and/or installing a bunch of CBs/fuses/switches which, as I said, doesn't make much sense because it introduces components that the VP system should eliminate. I've just finished the load planning analysis for the VP system. I'm just a go-up-and-look-down VFR pilot so we're not talking about the kind of instrument/night flying that Bob mentions in his response to Jim's very pertinent question. My backup is a hand-held radio. The Dynon has an internal backup battery and I'm using an AirGizmo-docked GPS which also has a battery. I was just curious how folks see electrical systems architecture evolving in consideration of this. BTW, I'm very pleased with the people at VP and am very excited to be working with their product. An RV-flying pal has three VP-200s in his new RV-10. -----Original Message----- From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of cjay Sent: Sunday, February 15, 2009 4:08 PM Subject: AeroElectric-List: Re: Single Bus [quote="bcollinsmn"] nuckolls.bob(at)aeroelect wrote: > At 07:34 AM 2/15/2009, you wrote: > > A few weeks ago I tried to get some feedback on approaching these > things by way of the Vertical Power system. I didn't see any reaction > to it. > > When I was at SteinAir a month or so ago for a Minnesota Wing (Van's > Air Force) meeting, Stein pointed out that the solid state setup is > the future of avionics. > > But I don't think I've ever seen this discussed on this board (which, > by the way, I consider to be THE single most valuable bulletin board > for homebuilders anywhere). > > It would be possible -- from what I can gather -- to set up a good > backup system, but not without circuit breakers/fuses/switches, which > defeats the purpose of the VP system. > > I'm just curious how you see this approach to aircraft wiring fitting > into some of the excellent advice you provide wrt avionics and > electrical system infrastructure? Bob, VP recommends an endurance bus as well, same concept as outlined in Z11. Nothing magical about VP, it just replaces the breakers/fuses/switches with solid state technology. I think a lot of people are going to be cautious for awhile because everthing flows through a self contained box. This simplifies design and installation; but a bit of faith is required until people start getting comfortable with the concept. I think they've got a good track record so far. cjay Read this topic online here: http://forums.matronics.com/viewtopic.php?p=230397#230397


    Message 13


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    Time: 03:34:53 PM PST US
    From: "Robert L. Nuckolls, III" <nuckolls.bob@aeroelectric.com>
    Subject: Re: Starting currents rusting the crankcase?
    At 03:41 PM 2/15/2009, you wrote: >My A&P mechanic told me to bolt the 2ga wire right next to the >starter. This asures the best ground dring the highest amp loading >on this circuit. Also, in some spam machines, it has been reported >that electrogalvanic corrosion was caused by forcing starter motor >current to run through the block, etc. to a ground wire on the rear >of the engine. > >Bob, comments from your experience? There's nothing wrong with getting grounded "close" to the starter but if there's a handier fat bolt I'm not sure I'd wrap more wire around the engine just to snuggle up to the starter. The voltage drop differences between the "worst" location on the crankcase and the "best" are very tiny and perhaps even difficult to measure. I've heard this "galvanic" thing tossed around in a host of conversations that spoke to every possible malady from rotting the skins at the rivets and overlaps to control surface hinges becoming detached. About 25 years ago, somebody posted a thing on the bulletin boards at Beech warning against the use of lead pencils to mark on aluminum sheet. The writer alluded to some inspectors squawk for a surface defect where a lead pencil was used to circle the area of interest on the skin. The story went that evil, metal-munching bits of graphite went to work on the aluminum and the whole disk fell out. I hadn't seen that little poster in many years and brought it up during some conversation with a processes and materials wiennie . . . he smiled and allowed as how the event didn't happen. Intuitively it makes a good tale but practically, you just can't get (1) enough voltage drop across such a low resistance joint in a crankcase for (2) sufficient time supported by (3) the necessary moisture to make such an event happen. Now, there HAVE been instances here currents circulating through engine parts have caused serious and relatively rapid damage. A shorted armature winding in a turbine engine starter-generator can cause circulating currents to flow in the generator's quill shaft and through the bearing balls that support the drive spline. This is a relatively low voltage (under 1v in some cases) but lots of current that causes the balls and races to become pitted. Bearing failure soon follows. Modern S-G designs add insulators between the quill shaft and armature shaft to prevent recurrences. But between non-moving, bolted-up faces of a crankcase? Don't think so. Bob . . .


    Message 14


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    Time: 04:33:19 PM PST US
    Subject: The future of avionics
    From: "bcollinsmn" <bob@rvbuildershotline.com>
    I meant to start a new thread regarding how the solid state system might change avionics infrastructure ahead, rather than hijack Jim's thread. So here it is. I did doublecheck and,yes, the configuration drawings for the VP-200 and the VP-100 do allow installation of an endurance buss. The VP-50 does not. -------- Bob Collins St. Paul, Minn. RV-7A (#&amp;^ fiberglass!) http://rvbuildershotline.com Day job: http://minnesota.publicradio.org/collections/special/columns/news_cut/ Read this topic online here: http://forums.matronics.com/viewtopic.php?p=230425#230425


    Message 15


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    Time: 07:05:25 PM PST US
    From: Speedy11@aol.com
    Subject: Re: AeroElectric-List Digest: 9 Msgs - 02/14/09
    Matt, What's up??? I got the email version of the list today and now I have to download a document to read all but the index?? Why the change?? Why can't you send the entire text as before?? Stan Sutterfield **************You can't always choose whom you love, but you can choose how to find them. Start with AOL Personals. (http://personals.aol.com/?ncid=emlcntuslove00000002)


    Message 16


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    Time: 10:03:43 PM PST US
    Subject: System Objectives
    From: "westexflyboy" <airplanedriver@gmail.com>
    I have three desired objectives for my RV-10's with dual electronic ignition: 1. Reliability 2. Low pilot workload to manage failures 3. Ability to use radios and EFIS prior to starting the engine (and leave them on during engine start) Z-14 architecture appears to meet objectives one and two. Z-14 might meet the third objective if I use the main battery to start the engine, the aux battery to power the radios and displays, and I start the engine with the crossfeed contactor open. Perhaps operating instructions for Z-14 would help - Where can I find those? -------- Chase Snodgrass Presidio, Texas www.flybigbend.com Simultaneous RV-10 twins under construction Read this topic online here: http://forums.matronics.com/viewtopic.php?p=230455#230455




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