---------------------------------------------------------- AeroElectric-List Digest Archive --- Total Messages Posted Sun 02/21/10: 9 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 07:57 AM - Next generation of OBAM aircraft? (Robert L. Nuckolls, III) 2. 08:45 AM - Re: Next generation of OBAM aircraft? (Robert Reed) 3. 10:50 AM - notes on Z Drawings (falconarf12a) 4. 11:52 AM - notes on Z Drawings (ROGER & JEAN CURTIS) 5. 12:08 PM - Stick drawing for warning lights (rparigor@suffolk.lib.ny.us) 6. 01:41 PM - Re: notes on Z Drawings (falconarf12a) 7. 02:06 PM - Re: notes on Z Drawings (falconarf12a) 8. 02:40 PM - Re: Re: notes on Z Drawings (ROGER & JEAN CURTIS) 9. 10:39 PM - Re: Failure Modes with Z14 (Jeff Page) ________________________________ Message 1 _____________________________________ Time: 07:57:28 AM PST US From: "Robert L. Nuckolls, III" Subject: AeroElectric-List: Next generation of OBAM aircraft? A recent development in gps aided stability and position holding not to mention energy management. http://vimeo.com/6194911 Bob . . . //// (o o) ===========o00o=(_)=o00o======== < Go ahead, make my day . . . > < show me where I'm wrong. > ================================ ________________________________ Message 2 _____________________________________ Time: 08:45:44 AM PST US From: Robert Reed Subject: Re: AeroElectric-List: Next generation of OBAM aircraft? I would love to get one of those to play with and a dozen or so for busines s.- Sure would be a lot cheaper method of doing aerial photography among other things.- I can see a business in the making.=0A=0A-=0A=0A=0A=0A__ ______________________________=0AFrom: "Robert L. Nuckolls, III" =0ATo: aeroelectric-list@matronics.com=0ASent: Sun, Fe bruary 21, 2010 11:54:48 AM=0ASubject: AeroElectric-List: Next generation o uckolls, III" =0A=0AA recent development in gps aided stability and position=0Aholding not to mention energy management .=0A=0A=0Ahttp://vimeo.com/6194911=0A=0A=0A- Bob . . .=0A=0A- - - - - - - - - ////=0A- - - - - - - - - (o o)=0A - ===========o00o=(_)=o00o======= ===0A- < Go ahead, make my day . . .- >=0A- < show me where I'm w rong.- - - >=0A- ================ ============ ________________________________ Message 3 _____________________________________ Time: 10:50:53 AM PST US Subject: AeroElectric-List: notes on Z Drawings From: "falconarf12a" How can I access the notes the are reference on the Z drawings? [Question] -------- SEL Read this topic online here: http://forums.matronics.com/viewtopic.php?p=287514#287514 ________________________________ Message 4 _____________________________________ Time: 11:52:56 AM PST US From: "ROGER & JEAN CURTIS" Subject: AeroElectric-List: notes on Z Drawings How can I access the notes the are reference on the Z drawings? [Question] -------- SEL The notes are listed in this section. http://www.aeroelectric.com/R12A/AppZ_12A4.pdf Roger ________________________________ Message 5 _____________________________________ Time: 12:08:06 PM PST US Subject: AeroElectric-List: Stick drawing for warning lights From: rparigor@suffolk.lib.ny.us I have a Europa monowheel with Rotax 914. Do have a Dynon D-10A piece of glass but engine and other instruments are analogue. I was thinking it would be neat to have a sketch/stick drawing of aeroplane missing aft section and have lights to indicate status or warnings. I have a 6" x 6" piece of real estateto work with on ceilingbegining a few inches aft of windscreen with conduits installed to run plumb in electron flow. Has anyone done something like thisr? Any pictures? Ideas, opinions and detailswelcomed. Ron Parigoris ________________________________ Message 6 _____________________________________ Time: 01:41:47 PM PST US Subject: AeroElectric-List: Re: notes on Z Drawings From: "falconarf12a" This link doesn't work for me......is it correct? http://www.aeroelectric.com/R12A/AppZ_12A4.pdf -------- SEL Read this topic online here: http://forums.matronics.com/viewtopic.php?p=287539#287539 ________________________________ Message 7 _____________________________________ Time: 02:06:42 PM PST US Subject: AeroElectric-List: Re: notes on Z Drawings From: "falconarf12a" OK never mind I got it to work!!!!! Thanks -------- SEL Read this topic online here: http://forums.matronics.com/viewtopic.php?p=287544#287544 ________________________________ Message 8 _____________________________________ Time: 02:40:35 PM PST US From: "ROGER & JEAN CURTIS" Subject: RE: AeroElectric-List: Re: notes on Z Drawings This link doesn't work for me......is it correct? http://www.aeroelectric.com/R12A/AppZ_12A4.pdf It works fine for me. Try www.aeroelectric.com > click on "Whats New" > go to Rev 12A Appendix Z Power distribution drawings. The notes are toward the end of the text portion, just prior to the drawings. Roger Read this topic online here: http://forums.matronics.com/viewtopic.php?p=287539#287539 ________________________________ Message 9 _____________________________________ Time: 10:39:43 PM PST US From: Jeff Page Subject: Re: AeroElectric-List: Failure Modes with Z14 > I guess my main point is that I do not route engine critical current > through a contactor. Why put more things to fail in those current paths. > I do run other systems, including starter current through a contactor. Yes, I intend to power the ignitions and fuel pump directly from the battery bus (through fuses of course). > The only time the crossfeed contactor closes is during engine cranking > or if I decide to manually close it after an alternator fails. I also > feed one cigarette lighter receptacle from a battery bus in case I ever > need to power a handheld device from it. Also comes in handy when camping. I re-wired the cigarette lighter in my Cessna so I could charge my phone at Sun n fun and Oshkosh :-) > Ken >> The only single failure I can think of that would cause a significant >> problem is an over voltage event that the OV module didn't address in >> a timely fashion, and the electronics in both ignitions fried. > > But that's a DUAL failure. An OV protection scheme fails > followed by a regulator running amok . . . > How many dual failures do you intend to hypothesize and > address as part of your FMEA? Failure of any single part should cause little concern, and probably little notice by an oblivious passenger. Probably most dual failures would mean full utilization of plan B, rather than a forced landing. The dual failure that merits my attention is both ignitions failing. With isolated electrical systems, that would be exceptionally unlikely. With Z13/8 and a B&C LR3C-14 (or equivalent), that could potentially happen. I don't plan on mounting it upside down so it can fill with water, but it is not impossible that I unknowingly make a similar mistake. In the event of an OV situation, I have to count on the controller and the circuit breaker both doing what they are supposed to do. Most of us have much confidence due to familiarity in the electrical items like alternators installed on our planes, because we have used them in cars etc. for years and have monitored their operation. And we know they fail sometimes. Who hasn't replaced an alternator ? At best we can occasionally test the OV circuitry. How many of us have extensive experience with the OV protection accomplishing its mission when it was needed ? How do I compare the sensitivity of the OV module compared to the ignition module ? If I install isolated systems to run the ignitions, I do not need to determine the potential for failure of the regulator, OV circuitry and circuit breaker. I know it seems like I am overly concerned about a very unlikely possibility. As ugly and maintenance prone as magentos are, they are unbelievably unlikely to both fail on the same flight. I don't want to replace them with another system, for which I can identify a possible failure mode that takes them both out, while addressing it only with "well, that is very unlikely". I need to either modify the design to eliminate the possibility, or be convinced that very unlikely is much more unlikely than, say, my prop coming off. I have no practical way of quantifying "very unlikely", so I am trying to eliminate the possibility. An isolated system is not excessively complex or expensive, I just need to determine the best way to do it. >> Then, in another post, you describe the in-flight fire in a Lancair >> IV-P due to the abused regulator/OV unit that I am planning on using ;-) > That wasn't an electronics failure but an INSTALLATION failure. Hopefully, due to the time spent learning from your book and this list (much appreciated !), together with my schooling and attention to detail, I won't make a similar error. > Similarly, you can't have a plan-b for loose prop bolts, thrown > jugs, ailerons lost to high speed flutter, etc. These things > are even more rare but offer exceedingly dire challenges to > your survival skills. The best I can do to mitigate some of these risks is to purchase quality parts and assemble them with mentors and mechanics checking my work, plus dual instruction in handling emergencies. >> An over voltage event is something I have no plan B for. > A optimally managed OV event becomes an LV even in tens > of milliseconds after onset of the failure. This is why > we generally don't bother to install OV annunciators > on the panel . . . but bulbs don't stay lit long enough > for you to make much use of what they have to tell you. > After the alternator is shut down, plan-b is the same > as if you'd thrown a belt, broken a wire, etc. As long as my ignitions are still working, plan B works well, otherwise I am landing in a very undesirable place :-( >> One way of addressing it, is two isolated systems running the >> ignitions. So although I really like Z13/8, Z14 has possibilities. >> Unlike Z13/8, Z14 has what seems to me to be a weakness. There is no >> essential bus diode, so a single contactor failure leaves the battery >> bus unpowered, in spite of having two working alternators. So if I >> have one electric fuel pump, and it happens to be on that battery bus, >> then my flight endurance is limited by battery capacity. > > If a fuel pump is critical to sustained flight, then why > don't you have two pumps? Z14 has no ENDURANCE bus because > one bus becomes the endurance bus should the other one be > taken down due to alternator failure. If the small alternator > quits, then most likely both busses can be kept up using > the larger alternator. If the big guy quits, then shut > the main bus down, reduce loads to get airport in sight using > small alternator . . . then close the cross-feed contactor > and use both batteries plus small alternator to terminate > the flight. The electric fuel pump is only necessary to back up the mechanical pump. It just seems odd that with the design of Z14, that with the single failure of a contactor, but two working alternators, there is no path to charge both batteries. With Z13/8 there are dual charging paths, which is a very nice design. > Make one of the Emags a self-powered version and wire > as shown in Figure Z-13/8 . . . you've got redundancy > to burn. Actually, I do intend to run one or two P-Mags. I just need to ensure I will not fry both of them with an OV event. > Run a 9011 multi-channel OV.LV monitor to annunciate > contactor failure. I have designed, but not yet prototyped a LV monitor that will annunicate LV on either battery, and be activated by either battery contactor switch or the "clearance delivery" switch (the don't drain the battery by leaving the switch on idiot feature). Some of the features of Z14 I probably don't need. There has been some discussion that two smaller batteries cannot delivery the same starter current that a single large battery can. Perhaps the solution is a modification to Z13/8, whereby the standby alternator is always in use to power the second ignition. Isolate that with a cross feed relay and add a second small battery. The cross feed relay would be only used to route power to the endurance bus after main alternator failure, but not to kick in the second battery during starting. Jeff Page Dream Aircraft Tundra #10 ------------------------------------------------------------------------------------- Other Matronics Email List Services ------------------------------------------------------------------------------------- Post A New Message aeroelectric-list@matronics.com UN/SUBSCRIBE http://www.matronics.com/subscription List FAQ http://www.matronics.com/FAQ/AeroElectric-List.htm Web Forum Interface To Lists http://forums.matronics.com Matronics List Wiki http://wiki.matronics.com Full Archive Search Engine http://www.matronics.com/search 7-Day List Browse http://www.matronics.com/browse/aeroelectric-list Browse Digests http://www.matronics.com/digest/aeroelectric-list Browse Other Lists http://www.matronics.com/browse Live Online Chat! http://www.matronics.com/chat Archive Downloading http://www.matronics.com/archives Photo Share http://www.matronics.com/photoshare Other Email Lists http://www.matronics.com/emaillists Contributions http://www.matronics.com/contribution ------------------------------------------------------------------------------------- These Email List Services are sponsored solely by Matronics and through the generous Contributions of its members.