---------------------------------------------------------- AeroElectric-List Digest Archive --- Total Messages Posted Mon 06/21/04: 25 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 04:47 AM - Re: Characterization of Westach 720-4a sensor (Trampas) 2. 06:01 AM - Faraday's Law (Eric M. Jones) 3. 06:19 AM - Re: 3 stage voltage regulator (Brian Lloyd) 4. 06:24 AM - Re: Characterization of Westach 720-4a sensor (Brian Lloyd) 5. 06:34 AM - Re: Battery data and etc (Paul Messinger) 6. 07:19 AM - Re: Battery data and etc (Brian Lloyd) 7. 07:24 AM - Re: engine hot starting (Paul Messinger) 8. 07:24 AM - Re: engine hot starting (Paul Messinger) 9. 08:32 AM - Re: AeroElectric-List off track???? (Robert L. Nuckolls, III) 10. 08:40 AM - engine hot starting and more on batteries (Brian Lloyd) 11. 08:53 AM - Re: engine hot starting and more on batteries (BobsV35B@aol.com) 12. 09:37 AM - Serial vs. Parallel altitude encoders (Mickey Coggins) 13. 09:39 AM - Re: Characterization of Westach 720-4a sensor (Jim Butcher) 14. 09:54 AM - Re: engine hot starting and more on batteries (Steve Richard) 15. 02:31 PM - private manned space flight (Brian Lloyd) 16. 03:01 PM - Automotive Landing Lights? (Bordelon, Greg) 17. 03:11 PM - wiring security (Larry McFarland) 18. 03:29 PM - Re: wiring security (Terry Watson) 19. 05:04 PM - Re: Automotive Landing Lights? (lm4@juno.com) 20. 06:33 PM - Re: Automotive Landing Lights? (Benford2@aol.com) 21. 07:06 PM - Re: engine hot starting and more on batteries (Paul Messinger) 22. 07:59 PM - Re: Battery data and etc (Paul Messinger) 23. 07:59 PM - Cont VS Bendix injection systems (Paul Messinger) 24. 09:18 PM - Re: Automotive Landing Lights? (Bordelon, Greg) 25. 10:49 PM - King KSG100 slaved Gyro (james.k.glindemann@exxonmobil.com) ________________________________ Message 1 _____________________________________ Time: 04:47:38 AM PST US From: "Trampas" Subject: RE: AeroElectric-List: Characterization of Westach 720-4a sensor --> AeroElectric-List message posted by: "Trampas" Check out the LM1815 chip from what you have described this chip will do what you need. http://www.national.com/pf/LM/LM1815.html Regards, Trampas www.sterntech.com -----Original Message----- From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of irampil@notes.cc.sunysb.edu Subject: AeroElectric-List: Characterization of Westach 720-4a sensor --> AeroElectric-List message posted by: irampil@notes.cc.sunysb.edu Greetings, Has anyone seen or developed a characterization of this tach sensor? It is a combined magnet/coil combo used to generate a pulse when a bit of iron speeds past(Ampere's law). In my case, I have 6 steel AN5 bolt heads/revolution roughly 3/32" from the sensor head at roughly 1000 inches/sec max. I'd like to know the expected output voltage and impedance so I can compute the input resistor for a 4n25. I need to divide the output pulse rate by 4 with a little TTL to get it into the frequency range for my tachometer system. Any advice? Ira N224XS flying, but due for a little panel rework ________________________________ Message 2 _____________________________________ Time: 06:01:41 AM PST US From: "Eric M. Jones" Subject: AeroElectric-List: Faraday's Law --> AeroElectric-List message posted by: "Eric M. Jones" --> AeroElectric-List message posted by: irampil@notes.cc.sunysb.edu >It is a combined magnet/coil combo used to generate a pulse when a >bit of iron speeds past (Ampere's law). Ira, You should immediately contact a lawyer and bring a lawsuit against your school. The law you state is Faraday's Law. Regards, Eric M. Jones www.PerihelionDesign.com 113 Brentwood Drive Southbridge MA 01550-2705 Phone (508) 764-2072 Email: emjones@charter.net ________________________________ Message 3 _____________________________________ Time: 06:19:18 AM PST US From: Brian Lloyd Subject: Re: AeroElectric-List: 3 stage voltage regulator --> AeroElectric-List message posted by: Brian Lloyd Christopher J Fortin wrote: > --> AeroElectric-List message posted by: Christopher J Fortin > > Hi Brian, > > I was wondering if this regulator -Cruzpro SAR20- might be suitable for > use in a plane. You can get it for less than $140 here in the states. > http://www.cruzpro.com/sar20.html It looks like it will do what you want but I know nothing about CruzPro. It is nice to see that you can program it for alternator size and battery size. I would want to know how they use that information to determine the absorption time. Sounds like it is time for a call to the company. Don't be surprised if it is a one-person operation. On the plus side, the owner will probably be willing to explain the system to you. -- Brian Lloyd 6501 Red Hook Plaza brianl@lloyd.com Suite 201 http://www.lloyd.com St. Thomas, VI 00802 +1.340.998.9447 (voice) +1.360.838.9669 (fax) There is a time to laud one's country and a time to protest. A good citizen is prepared to do either as the need arises. ________________________________ Message 4 _____________________________________ Time: 06:24:39 AM PST US From: Brian Lloyd Subject: Re: AeroElectric-List: Characterization of Westach 720-4a sensor --> AeroElectric-List message posted by: Brian Lloyd Trampas wrote: > --> AeroElectric-List message posted by: "Trampas" > > Check out the LM1815 chip from what you have described this chip will do > what you need. > http://www.national.com/pf/LM/LM1815.html That is exactly what he needs. Wow, all that in one package. Who would'a guessed. It has been a long time since I have poked through a Nat Semi catalog. -- Brian Lloyd 6501 Red Hook Plaza brianl@lloyd.com Suite 201 http://www.lloyd.com St. Thomas, VI 00802 +1.340.998.9447 (voice) +1.360.838.9669 (fax) There is a time to laud one's country and a time to protest. A good citizen is prepared to do either as the need arises. ________________________________ Message 5 _____________________________________ Time: 06:34:47 AM PST US From: "Paul Messinger" Subject: Re: AeroElectric-List: Battery data and etc --> AeroElectric-List message posted by: "Paul Messinger" > Now that we have traded ideas and insults, may I buy you a beer at OSH so we can discuss battery and charging technology at greater length? > > -- > Brian Lloyd Well done Paul ________________________________ Message 6 _____________________________________ Time: 07:19:39 AM PST US From: Brian Lloyd Subject: Re: AeroElectric-List: Battery data and etc --> AeroElectric-List message posted by: Brian Lloyd Paul Messinger wrote: > --> AeroElectric-List message posted by: "Paul Messinger" > >>Now that we have traded ideas and insults, may I buy you a beer at OSH so > > we can discuss battery and charging technology at greater length? > >>-- >>Brian Lloyd > > > Well done Well, getting all pissy at each other doesn't really solve anything, does it. Drinking beer after a day of flying or playing with airplanes is far more pleasant. By the way, seems you got the BIG guns to wade in on your side of the engine starting question. So are you going to share your starting procedure? -- Brian Lloyd 6501 Red Hook Plaza brianl@lloyd.com Suite 201 http://www.lloyd.com St. Thomas, VI 00802 +1.340.998.9447 (voice) +1.360.838.9669 (fax) There is a time to laud one's country and a time to protest. A good citizen is prepared to do either as the need arises. ________________________________ Message 7 _____________________________________ Time: 07:24:43 AM PST US From: "Paul Messinger" Subject: Re: AeroElectric-List: engine hot starting --> AeroElectric-List message posted by: "Paul Messinger" Well said and I completely agree. Worked for me! Paul ----- Original Message ----- From: "George Braly" Subject: RE: AeroElectric-List: engine hot starting > --> AeroElectric-List message posted by: "George Braly" > > > Brian, > > Your technique is common for hot starts. > > It is not the technique that makes use of knowledge as to what the real > problem is. And it is a technique that can be very dangerous and cause > a fire that can and has consumed an airplane. > > Getting fuel flow indications may indicate that "vapor is purged" - - > but is not at all an indication that you are not going to vapor lock > about 3-5 seconds after the engine fires up - - and then promptly stops. > > The reasons these engines are hard to start when HOT is very simple. > > The fuel pump core is HOT - - so hot that when new fuel hits the core of > the engine driven fuel pump it flashes to vapor and vapor locks the > inlet to the fuel pump. > > Until you sufficiently cool off the core of the fuel pump it will ALWAYS > - - ALWAYS vapor lock. > > You either have to: > > 1) cool off the core of the engine driven fuel pump (easy with a TCM > fuel system); or, > > 2) You have to use the electric boost pump to keep the engine running > until the core of the engine driven pump does cool off enough to quit > flashing the incoming fuel to vapor (typical Lycoming and some twin > Cessna techniques). > > After the fuel pump core components are cooled off, the engine will > actually start better than when cold. > > Regards, George > > > -----Original Message----- > From: owner-aeroelectric-list-server@matronics.com > [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Brian > Lloyd > To: aeroelectric-list@matronics.com > Subject: Re: AeroElectric-List: engine hot starting > > --> AeroElectric-List message posted by: Brian Lloyd > > Paul Messinger wrote: > > > I do know 99% of owners have a heck of a time with hot starts and most > say > > they are using the acft manual procedure. Well I had problems with my > Beech > > hot starting until I forgot the manual and was told how to start just > about > > any brand or injected engine works every time and seldom more than a > few > > seconds. > > I agree that the hot-start technique usually provided in the pilot's > handbook doesn't work very well. With Lycoming or Continental engines I > find that the flooded start technique works quite well although it does > require a bit of cranking. The technique I use is as follows: > > 1. Throttle and mixture full forward, i.e. full throttle and rich > mixture. > > 2. Boost pump on until you see a stable fuel-flow indication. This > means the vapor is purged from the system. > > 3. Mixture to idle-cut-off (ICO) and boost pump off. > > 4. Crank the engine. > > 5. When the engine fires, retard the throttle and advance the mixture. > > This technique works very reliably as the fuel lines and other > components are cooled with fresh fuel and fuel vapor is purged from the > lines. The problem now is that the engine is just about guaranteed to > be flooded. Cranking with the throttle wide open admits the maximum > amount of air and the mixture at ICO precludes any more fuel being > admitted to the engine. As the engine cranks the mixture, which was > initially too rich to fire, becomes progressively leaner until the > engine fires. At that point the throttle is retarded and the mixture > advanced to allow the engine to operate normally. > > >> It doesn't matter whether you think that the Lycoming injection > system > >> (actually Bendix RSA) is better or worse than Continental's (I happen > to > >> think it is better because it is a closed-loop servo system based on > mass > >> airflow measurement), the key point is that the problem I described > CAN and > >> DOES happen on a regular basis. > > > > I agree it happens on a regular basis but I disagree it needs to > happen > > nearly as often. I have yet to see the fool proof hot start procedure > in any > > manual. > > I agree with both of your statements. > > > The best system in my opinion is the one on the S35 and its so unique > its > > got a special section in the A&P manual. One simple dual spool rotary > valve > > and easy to use and dirt simple. Works all the time! > > It does have the advantage of being simpler than the Bendix RSA system > but it has no mechanism to prevent the engine from getting too rich to > operate. Leaving the boost pump in the high position can flood even a > running engine. > > > The Cont systems I have personal experience have a fuel pump return > line > > back to the tank and the Lyc's have no return line. Thus not only is > the > > fuel in the low pressure injecton lines boiled off but the engine > driven > > pump heats its fuel and in the LYC case you cannot flush the hot fuel > out so > > those designs are designed to be harder to start. > > The "flooded start" procedure I outlined above works quite well but you > may have to crank for 15 seconds or so depending on how much fuel you > had to push through the injection system to purge the fuel vapor. > > I also like the fact that the Bendix fuel servo compensates for changes > in fuel pressure and adjusts the flow accordingly. Also the mass > airflow sensing causes the mixture to be more consistent as the aircraft > changes altitude thus reducing cockpit workload for the pilot during > climb and descent. > > Both systems work pretty well but they are very different. I do find it > interesting to note that the popular modern aftermarket continuous-flow > injection systems from Airflow Performance are based on the principles > in the Bendix RSA system. The Bendix RSA fuel injection system is > pretty old now and could use some updating but we all know how likely > that is given the regulatory nature of the FAA. Bendix has no > motivation to improve their system. > > >> In a perfect world, maybe. If you feed the engine the proper > mixture, it > >> will fire and run. In a hot start that can be difficult and many > OBAM > >> aircraft have very tight cowls that retain heat on the ground causing > the > >> entire fuel system to become heat-soaked. Ensuring the proper > mixture then > >> becomes a crap shoot. They can be a real bitch to hot-start even if > you > >> hold your tongue right and the airplane gods are on your side. > > > > See above My experience appears to differ > > Great! I am eager to learn. What is your technique? My technique > works but I would much rather save the wear and tear on the starter and > battery if possible. > > >> So perhaps you knew the magic incantation to make your engine start > in three > >> blades at all times but I think that the experience of the > run-of-the-mill > >> pilot will be different. I accept that it is possible that the pilot > may > >> have a period of extended cranking which will heat up and discharge > the > >> battery. That is the safest assumption and I prefer to design for > that. > > > > So what and what is your point as the number of deep cycles in the > battery > > is small compared to the battery design if you choose the proper > battery. > > If you recall, I was pointing out how a thermal runaway event in a > battery could be initiated on a hot day with a prolonged cranking event > and how a high initial charge rate could exacerbate the problem. > Temperature sensing on the battery would reduce the voltage and hence > the charge rate thus saving the battery. I wasn't talking about deep > cycles at all. > > I think that we got off on the wrong foot when I pointed out that AGMs > have shorter lifetimes in deep cycle service than do gell-cells. I > agree that deep cycle service is unusual in an aircraft except where > there is a failure and that is not normal operation. But I did want to > emphasize that there is confusion in people's minds between gell-cell > batteries and AGM batteries and that you need to adjust the charging > system to accommodate the type of battery you have installed in your > aircraft and the temperature at which that battery is operating. > > One thing that *is* worth considering is that the difference between > charge and float voltages in gell-cell batteries are much closer > together than are the charge and float voltages for flooded-cell and AGM > batteries. If you are going to have a charging system with only a > single set-point, I think you may find that the gell-cell lives longer > than the AGM in that environment. > > In my RV-4 I installed an over-sized gell-cell that would power my > e-buss for 4 hours, the normal fuel duration of the aircraft. I knew > that if I got to the end of the battery capacity, I probably had other, > more pressing problems to deal with. The point is that the bigger > gell-cell was able to crank the O-320 very happily thus validating the > "bigger battery means more current" philosophy. > > And you may be right that the Odyssey battery is the be-all and end-all > of batteries. It may be so robustly constructed that it takes the abuse > without damage so all this may be a moot point. > > But I still believe that one should operate all the devices in an > aircraft as conservatively as possible. It won't hurt your Odyssey > battery to perform a proper three-stage charge cutting off to the proper > float voltage, will it? > > Pax? > > -- > Brian Lloyd 6501 Red Hook Plaza > brianl@lloyd.com Suite 201 > http://www.lloyd.com St. Thomas, VI 00802 > +1.340.998.9447 (voice) +1.360.838.9669 (fax) > > There is a time to laud one's country and a time to protest. > A good citizen is prepared to do either as the need arises. > > > == > == > == > == > > ________________________________ Message 8 _____________________________________ Time: 07:24:43 AM PST US From: "Paul Messinger" Subject: Re: AeroElectric-List: engine hot starting --> AeroElectric-List message posted by: "Paul Messinger" I agree with both of your statements. > > > The best system in my opinion is the one on the S35 and its so unique its > > got a special section in the A&P manual. One simple dual spool rotary valve > > and easy to use and dirt simple. Works all the time! > > It does have the advantage of being simpler than the Bendix RSA system but it has no mechanism to prevent the engine from getting too rich to operate. Leaving the boost pump in the high position can flood even a running engine. Please read the book as there is NO hi or low boost on this system. Also because there is a return line one can cycle fresh (cool) fuel thru the system including the engine driven fuel pump. This reduces the amount of hot fuel to vaporize when the mix is off idle cutoff. Boost pump on is normal during airport ops and with no hi or low position no worries of flooding. Again its the dirt simple system and simple worked great for me for years. Again its different from Lyc's of the time and also different from other Bendix systems. Been too long to remember exactly the procedure but as I recall its is slightly different from what you said. First full open throttle mix to idle cutoff Aux pump on (single speed pump) for several seconds to purge the fuel system of hot fuel (the fuel not in the injecton lines) Crank engine and when it fires close throttle and gradually move mix from cutoff to rich. Not as hard as it seems. The above avoids the totally flooded engine one gets with your procedure and allows a faster start. Not sure it would work with a setup where there was no fuel return line that can be purged of hot fuel so you have a cold non flashing fuel supply going into the injector lines. > But I did want to emphasize that there is confusion in people's minds between gell-cell batteries and AGM batteries and that you need to adjust the charging system to accommodate the type of battery you have installed in your aircraft and the temperature at which that battery is operating. I agree and that may be one reason why Concord batteries seem to have a shorter life in many aircraft with non adjustable regulators that are setup for high voltage for fast recharging of the flooded type batteries. > > One thing that *is* worth considering is that the difference between charge and float voltages in gell-cell batteries are much closer together than are the charge and float voltages for flooded-cell and AGM batteries. If you are going to have a charging system with only a single set-point, I think you may find that the gell-cell lives longer than the AGM in that environment. My opinion from day one on this discussuon is NOT that proper care can make the battery last longer but with the current common design what is specifically the life. Frankly I do not need a 10 year battery and if I can get 3-5 years with a current system why go to a lot of trouble and $$ for a gain I do not need. lots of corrent statementa abouut shortened life but shortened from to what. 10 years to 4?? 1000 flight hours to 200 This is what we all need to see if your persomal flight habits need a differrent battery charging system. I have a friend that recently sold his acft and he had a Optima (the round one) Legally installed in his spam can. It was 6 years old and was working just fine. He had a hard time starting the engine and ran it down on a regulator basis and also had over 1000 hours on the battery. Stock regulator non temp sensing etc. He saw no need for a different system. Turns out, at least at that time, the 337 was approved as Optima had passed and has available all the FAA requirements for an aircraft install and his IA filled out the paper and thus it was legal. Bottom line 6 years is longer than I would want to go between battery replacements so why get fancy for a 10 year life. > >> > And you may be right that the Odyssey battery is the be-all and end-all of batteries. It may be so robustly constructed that it takes the abuse without damage so all this may be a moot point. I am not pushing Odyessy, but they only cost around double the Panasonic and still well under $100 delivered and have the ability to sit around with NO need for a float charger to keep it topped off like the Panasonic does. > > But I still believe that one should operate all the devices in an aircraft as conservatively as possible. It won't hurt your Odyssey battery to perform a proper three-stage charge cutting off to the proper float voltage, will it? Hurt, no but needed, I really do not think so. The standard constant Voltage charge is very close to the first two stages. Hundreds of $$ and another pound as well as several extra wires and a couple of fuses to install the SAR 3 for questionable improvement over what I already get just seems to be a unnecessary complexity. Get a $50 adjustable reg and mount it near the battery (for temperature compensation) and be done with it. Set the V on the low side of the range and you are likely to get battery life that exceeds the reasonable battery replacement cycle time. As I said what is the improvement needed over 4-5 years?? I do not need any longer life. Use the proper low cost regulator and get both temp compensation and voltage set for under $50. and no need for extra temp sensor. The B&C reg is nearly $300 with the temp sensor option. lets see, 6X the cost and no ability to adjust voltage. WHY go there?? The SAR 3 is even more expensive for what. Longer than what life. Likely longer than I would ever need but that is an individual decision. Bob suggests panasonic replacement on an annual basis. This coupled with the average under 100 flight hours per year makes sense to me. So I have Odyssey batteries in the cabin and the reg is temperature compensated V set type. Two batteries and a regulator for around $200 total. Expected annual cost $50 based on a biannual battery replacement. Also I disagree with Bob's position on putting the fresh battery in the main position. I want to know what the battery capacity is in an emengency so the new battery is in the backup position. And yes I do load test annually as that is so simple to do with NO extra equipment other than a clock :-) Paul ________________________________ Message 9 _____________________________________ Time: 08:32:39 AM PST US From: "Robert L. Nuckolls, III" Subject: AeroElectric-List: Re: AeroElectric-List off track???? --> AeroElectric-List message posted by: "Robert L. Nuckolls, III" >Comments/Questions: Bob, > >Sending this to you off list as I don't want to be seen as unappreciative >of others well meant efforts. >I took your seminar a couple of years ago at Watsonville and have been a >happy lurker on the list ever since, learning as I go until I come to do >my electrical system. Maybe it's just me but it seems like the tone of the >aeroelectric list has changed in the past couple of months from a fun to >read and informative list that explained things in terms my electronically >challenged mind could understand. It now seems we have a couple of >engineers (no disrespect intended !!) using the list to prove and disprove >stuff that frankly I don't understand and don't think I need to understand. Understand. I'm going to echo this to the list and strip of your name because while your comments and frustration are understandable, there are very good reasons for this condition. Further, it's a situation over which YOU and all other lurkers have a great deal of control. >I've now taken to simply deleting most of their messages unread, which is >a shame because there's probably a lot of things they could teach, but not >with the same good grace and patience you've exhibited. Basically they >seem to have monopolized the list and although I'm sure they have lots of >experience and knowledge to offer frankly their style is somewhat >intimidating to us amateurs. > >Not sure there's much if anything you can or should do and perhaps I'm off >base etc and out of line. Just thought my perspective may be of interest. Folks who are members of the OBAM aircraft community are a diverse collection of individuals with huge variability in interests, skills, knowledge and motivations. I suspect that a majority of our brethren have interests pretty much in line with your own . . . let's get this airplane done with a minimum of effort and maximize return on investment for time invested to achieve utility and performance in an airplane. At the same time there are folks who have an interest in supplying products. I have an information gathering and dissemination activity and sell a few fabricated products. Others have no interest at all in building or owning an aircraft but they're really good at gathering, organizing, advertising and providing parts procurement services. Irrespective of your (or anyone else's) motivations, there is an underlying foundation common to the success of everyone's goals in this community. The discovery, understanding and practical application of simple ideas. Doesn't matter if you're struggling over the selection of a screw and wire-bundle clamp or mitigating probability of a gremlin of some variety spiking your $high$ radio. Once you've peeled back all the myths, misunderstandings and/or marketing hype, the ANSWER IS ALWAYS STONE SIMPLE and easy to UNDERSTAND. When things don't perform as desired and a modification of materials and techniques are called for, the ANSWER IS ALWAYS STONE SIMPLE and easy to UNDERSTAND. >Appreciate you sharing your experience over the years. Thank you. I'm pleased that you find my contributions useful. However, pleased keep in mind that the AeroElectric-List was established for the same reasons as the Aero-Electric Connection book. . . to be a forum and gathering place for the best we know how to do. Just yesterday I was wrapping up a weekend seminar in Long Beach and made the comment that while I write and edit the 'Connection, it's not MY book. Its creation and content is totally driven by the participation of folks who participate in the discussions that precede the publication of words. It's not practical or useful for me to write about everything I've learned in the past 40 years . . . it's best to write when I can contribute to mitigation of YOUR questions in a quest of a achieving YOUR goals. The 'Connection came into existence about 1988 base on my perceptions of need. I'd spent a week at OSH answering questions out of B&C's booth. My perception was that the electrical system was the least understood system on the airplane. The following year, the first few chapter were published and the plan is to continue to grow it even after all these years. However, it SHOULD grow based on your questions are and not on what this guy Bob Nuckolls thinks you should know. The 'List is exactly the same. The List SHOULD be (and in fact IS) exactly what you and other participants make it. I'll grant you that there will be times when some of the List's techno-nerds stir a pot of ideas where you'd rather wait until the final paragraph is published before you read it. But please keep in mind that this is YOUR list. If the conversations are short on topics of interest to you, it's only because you've not asked any questions about those topics. I nor anyone else on the list should take on the responsibility for moderating or otherwise driving the direction of conversation on the list. This isn't the kindergarten of aviation technology and skills . . . it's a graduate course where we all have duties of participation. I've avoided invoking suggestions in Matt's missives on "proper use of the AeroElectric-List" when conversations might appear to be off-topic. I personally welcome ANY discussion that goes to the discovery and application of simple ideas whether or not they're germane to electrical systems or avionics. When I or anyone else seems to dominate the list with discussions centered in our favorite OBAM aircraft discipline, that perception of dominance is driven only by an unwillingness of others to accommodate their own interests right along with everyone else. It would be a really great thing if the 'Connection and the 'List were core data sources for 95% of the OBAM aircraft under construction . . . but it isn't going to happen. I believe there are a relatively few numbers of builders at the top of the bell-curve that quest for useful, simple- ideas. It's those folks who are pushing the state of our art forward. The rest are simple consumers . . . which is perfectly fine. They too contribute to the gross numbers of aircraft that make our hobby a significant force in aviation. So my friend, I'd like to believe that you have properly positioned yourself in the OBAM community membership who map at the top of the bell-curve in a quest for knowledge. So, how may I or anyone else on the List be of service to you today? Bob . . . ________________________________ Message 10 ____________________________________ Time: 08:40:49 AM PST US From: Brian Lloyd Subject: AeroElectric-List: engine hot starting and more on batteries --> AeroElectric-List message posted by: Brian Lloyd Paul Messinger wrote: > Please read the book as there is NO hi or low boost on this system. It has been a long time since I have flown behind a big Continental but I do remember the hi/lo boost pump. You say they did away with it? > Also > because there is a return line one can cycle fresh (cool) fuel thru the > system including the engine driven fuel pump. This reduces the amount of hot > fuel to vaporize when the mix is off idle cutoff. That is a definite win. > Boost pump on is normal during airport ops and with no hi or low position no > worries of flooding. Again its the dirt simple system and simple worked > great for me for years. Then where did I get the idea there is a high/low boost pump? I am sure it was from Continental engines. The Bendix RSA injection system has only on/off for the boost pump. > Again its different from Lyc's of the time and also different from other > Bendix systems. OK. > Been too long to remember exactly the procedure but as I recall its is > slightly different from what you said. > > First full open throttle > mix to idle cutoff > Aux pump on (single speed pump) for several seconds to purge the fuel system > of hot fuel (the fuel not in the injecton lines) > > Crank engine and when it fires close throttle and gradually move mix from > cutoff to rich. Not as hard as it seems. > > The above avoids the totally flooded engine one gets with your procedure and > allows a faster start. That sounds a lot like the start procedure listed in the aircraft manual. It does not work well for the Lyc IO-540 in the Aztec. The fuel in the injector lines and the flow divider is already vaporized. > Not sure it would work with a setup where there was no fuel return line that > can be purged of hot fuel so you have a cold non flashing fuel supply going > into the injector lines. Right. That is the Achilles heel of the Bendix RSA system. Maybe George Braly will answer my question. If anyone knows how to deal with these injected engines, it is him. (For those who don't know, George Braly is the head engineer for GAMI.) >> But I did want to emphasize that there is confusion in people's minds >> between gell-cell batteries and AGM batteries and that you need to adjust >> the charging system to accommodate the type of battery you have installed in >> your aircraft and the temperature at which that battery is operating. > > I agree and that may be one reason why Concord batteries seem to have a > shorter life in many aircraft with non adjustable regulators that are setup > for high voltage for fast recharging of the flooded type batteries. I agree with that. Going back to the Deka white paper on their sealed batteries (the following is a quote from page 12): "If the right pressure (voltage) is used for the temperature, a battery will accept charge at its ideal rate. If too much pressure is used, charge will be forced through the battery faster than it can be stored. Reactions other than the charging reaction occur to transport this current through the battery -- mainly gassing. Hydrogen and oxygen are given off faster than the recombination reaction. This raises the pressure until the pressure relief valve opens. The gas lost cannot be replaced. Any VRLA battery will dry out and fail prematurely if it experiences excessive overcharge. Note: It is the pressure (voltage) that initiates this problem -- a battery can be over-charged (damaged by too much voltage) even though it is not fully charged. This is why charging voltage must be carefully regulated and temperature compensated to the values on page 11." To me, this argues very persuasively for proper temperature compensation. >>One thing that *is* worth considering is that the difference between >> charge and float voltages in gell-cell batteries are much closer together >> than are the charge and float voltages for flooded-cell and AGM batteries. >> If you are going to have a charging system with only a single set-point, I >> think you may find that the gell-cell lives longer than the AGM in that >> environment. > > My opinion from day one on this discussuon is NOT that proper care can make > the battery last longer but with the current common design what is > specifically the life. Frankly I do not need a 10 year battery and if I can > get 3-5 years with a current system why go to a lot of trouble and $$ for a > gain I do not need. > > lots of corrent statementa abouut shortened life but shortened from to what. > 10 years to 4?? 1000 flight hours to 200 This is what we all need to see if > your persomal flight habits need a differrent battery charging system. Perhaps you are right. OTOH, I have experienced early battery failure. The best case is that you end up stuck at some unknown airport trying to buy a new battery or get a jump start. Worst case is that the alternator fails and you watch your battery go flat in a few minutes. Flying IFR with a flashlight stuck in your mouth while using a handheld comm and a handheld GPS to navigate doesn't strike me as particularly fun. It doesn't strike me as being all that hard to ensure a proper battery charge so that the battery will be in good shape should you need it to carry your endurance loads. As Chris Fortin found, there are three-stage charge controllers available for very reasonable prices. If you can get a good temperature-compensated three-stage regulator for $140, why not? Your battery will be happier and maybe you will find that your battery will truly last 5 years. When you abuse your battery you shorten its life. Now its life isn't some absolute number like 5 years, battery failures will average out to be something like 5 years, with some lasting longer and some having shorter lives. When you abuse the battery you reduce that time and perhaps greatly increase the incidence of total failure at an early age (as I did with the Concorde AGMs). Even if I decide I am going to get a new battery every one or two years, doesn't it make sense that I treat it well so that the chance of early failure is as low as possible? > I have a friend that recently sold his acft and he had a Optima (the round > one) Legally installed in his spam can. It was 6 years old and was working > just fine. He had a hard time starting the engine and ran it down on a > regulator basis and also had over 1000 hours on the battery. Stock regulator > non temp sensing etc. He saw no need for a different system. Lucky him. > Turns out, at least at that time, the 337 was approved as Optima had passed > and has available all the FAA requirements for an aircraft install and his > IA filled out the paper and thus it was legal. That is certainly nice. I will consider that when it comes time to change the battery again. This kind of thing is much more important in Spam cans where you don't get the option of building a really good electrical system such as we do with OBAM and other experimental aircraft. > Bottom line 6 years is longer than I would want to go between battery > replacements so why get fancy for a 10 year life. That is fine. Now I am interested in reducing early failures to zero. >>And you may be right that the Odyssey battery is the be-all and end-all of >> batteries. It may be so robustly constructed that it takes the abuse >> without damage so all this may be a moot point. > > I am not pushing Odyessy, but they only cost around double the Panasonic and > still well under $100 delivered and have the ability to sit around with NO > need for a float charger to keep it topped off like the Panasonic does. All batteries have some level of self discharge. The lead alloy can reduce that to some extent but you can't eliminate that. The warmer the battery, the faster the level of self discharge. Keeping a battery on a proper float charge is a safe thing to do. YMMV. >>But I still believe that one should operate all the devices in an aircraft >> as conservatively as possible. It won't hurt your Odyssey battery to >> perform a proper three-stage charge cutting off to the proper float voltage, >> will it? > > Hurt, no but needed, I really do not think so. The standard constant Voltage > charge is very close to the first two stages. Hundreds of $$ and another > pound as well as several extra wires and a couple of fuses to install the > SAR 3 for questionable improvement over what I already get just seems to be > a unnecessary complexity. Certainly the SAR-3 from Ample Power is overkill. The dual-display EFIS-1 from Blue Mountain is too but I am putting it in nonetheless. A Garmin 530 is too. There is no added complexity as it wires up the same way an automotive VR does (with the exception of the temp sensor). > Get a $50 adjustable reg and mount it near the battery (for temperature > compensation) and be done with it. Set the V on the low side of the range > and you are likely to get battery life that exceeds the reasonable battery > replacement cycle time. I don't completely agree with this as the battery may be at a different temperature than its surroundings. The only way to measure battery temperature for sure is to actually attach the measuring device to the battery. Remember that the battery is going to get warm during charge and it is going to be warmer than the surrounding air. Who knows what the current through the VR is going to do to the temperature of the VR. I can safely say that the two of them will *NOT* be at the same temperature unless the VR is firmly attached to the battery. Also, what is the temperature compensation curve in these cheap regulators? Does it match what the battery requires? I think not. I bet it is just something like a reduced voltage drop across a couple of diodes in the VR reference circuit, not exactly tailored to the voltage settings required for a proper battery charge. > As I said what is the improvement needed over 4-5 years?? I do not need any > longer life. But I want higher reliability and less chance of initial failure in the time that I do keep my battery, even if it is only two years. > Use the proper low cost regulator and get both temp compensation and voltage > set for under $50. and no need for extra temp sensor. Again, I don't believe that will work. > The B&C reg is nearly $300 with the temp sensor option. lets see, 6X the > cost and no ability to adjust voltage. WHY go there?? The SAR 3 is even more > expensive for what. Longer than what life. Likely longer than I would ever > need but that is an individual decision. Bob suggests panasonic replacement > on an annual basis. This coupled with the average under 100 flight hours per > year makes sense to me. > > So I have Odyssey batteries in the cabin and the reg is temperature > compensated V set type. > > Two batteries and a regulator for around $200 total. Expected annual cost > $50 based on a biannual battery replacement. Certainly that is a way to go. But now many people on this list now have a better idea how all this works and can make a choice for themselves? How many people on this list are building beautiful works of mechanical art and want to do everything as perfectly as possible? Achieving perfection even in the small things can be a reward in and of itself. Please don't run that down. > Also I disagree with Bob's position on putting the fresh battery in the main > position. I want to know what the battery capacity is in an emengency so the > new battery is in the backup position. And yes I do load test annually as > that is so simple to do with NO extra equipment other than a clock :-) Perhaps. OTOH, it is the main battery that gets all the use. I also think that it is a good idea to deep cycle the battery at least once to see what its real capacity is. Then I can put it in the airplane knowing what it will *really* do. -- Brian Lloyd 6501 Red Hook Plaza brianl@lloyd.com Suite 201 http://www.lloyd.com St. Thomas, VI 00802 +1.340.998.9447 (voice) +1.360.838.9669 (fax) There is a time to laud one's country and a time to protest. A good citizen is prepared to do either as the need arises. ________________________________ Message 11 ____________________________________ Time: 08:53:45 AM PST US From: BobsV35B@aol.com Subject: Re: AeroElectric-List: engine hot starting and more on batteries --> AeroElectric-List message posted by: BobsV35B@aol.com In a message dated 6/21/04 10:42:21 AM Central Daylight Time, brianl@lloyd.com writes: It has been a long time since I have flown behind a big Continental but I do remember the hi/lo boost pump. You say they did away with it? Good Morning Brian, Let us not say they have done away with it, just that it has come and gone, then come back again often depending on the perceived need. In almost all cases where there is a high and low position of the boost pump used in a Continental powered Bonanza, or derivative, aircraft, the low position is just a switch contact which runs the current through an appropriately sized resistor. Same pump, no big deal. Happy Skies, Old Bob AKA Bob Siegfried Ancient Aviator Stearman N3977A Brookeridge Airpark LL22 Downers Grove, IL 60516 630 985-8502 ________________________________ Message 12 ____________________________________ Time: 09:37:02 AM PST US From: Mickey Coggins Subject: AeroElectric-List: Serial vs. Parallel altitude encoders --> AeroElectric-List message posted by: Mickey Coggins Hi, I've purchased a narco AT 155 transponder, and it requires a parallel altitude encoder. When I bought it at SNF the encoder I planned to use (Dynon) provided a parallel output. Now, their new model only provides serial output. I guess my options are to change my transponder, buy a different encoder, buy the old model of Dynon, or get a box to do a conversion. Any words of wisdom from the group on this? Thanks, Mickey -- Mickey Coggins http://www.rv8.ch/ #82007 QB Wings/Fuselage ________________________________ Message 13 ____________________________________ Time: 09:39:00 AM PST US From: "Jim Butcher" Subject: AeroElectric-List: Re: Characterization of Westach 720-4a sensor --> AeroElectric-List message posted by: "Jim Butcher" Ira, Greg at BMA has suggested to me that I use a BMA current senser (Hall effect) to measure the pulses Rotax generates for the electric tach. Haven't tried it yet, but this summer for sure. Jim Butcher Europa A185 ________________________________ Message 14 ____________________________________ Time: 09:54:16 AM PST US From: "Steve Richard" Subject: RE: AeroElectric-List: engine hot starting and more on batteries --> AeroElectric-List message posted by: "Steve Richard" Just another data point: I have a Continental TSIO-520 in a Mooney. I had difficulty starting it when hot until I talked to a ex-Mooney test pilot (he writes for one of the Mooney mags now). He told me the problem with Cont. is fuel starvation. He also told me that the primer button puts fuel in the 'manifold' and the low/high buttons put fuel in the injectors. I was trying to hot start using the primer button. He told me I would never get enough fuel in the cylinders to get thing going. His hot start method: All controls full forward Hi boost for 2-3 seconds. Throttle to 3/4" forward of closed. Crank (Momentary pushes on low boost to help things along) Can't vouch for the fuel layout described above but it works every time. Steve Richard steve@oasissolutions.com -----Original Message----- From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com]On Behalf Of BobsV35B@aol.com Subject: Re: AeroElectric-List: engine hot starting and more on batteries --> AeroElectric-List message posted by: BobsV35B@aol.com In a message dated 6/21/04 10:42:21 AM Central Daylight Time, brianl@lloyd.com writes: It has been a long time since I have flown behind a big Continental but I do remember the hi/lo boost pump. You say they did away with it? Good Morning Brian, Let us not say they have done away with it, just that it has come and gone, then come back again often depending on the perceived need. In almost all cases where there is a high and low position of the boost pump used in a Continental powered Bonanza, or derivative, aircraft, the low position is just a switch contact which runs the current through an appropriately sized resistor. Same pump, no big deal. Happy Skies, Old Bob AKA Bob Siegfried Ancient Aviator Stearman N3977A Brookeridge Airpark LL22 Downers Grove, IL 60516 630 985-8502 ________________________________ Message 15 ____________________________________ Time: 02:31:10 PM PST US From: Brian Lloyd Subject: AeroElectric-List: private manned space flight --> AeroElectric-List message posted by: Brian Lloyd Scaled Composite's "Space Ship 1" completed a successful manned-flight to 100Km this morning. Looks like they are well on the way to winning the X-prize. Wow, when I heard of the X-prize several years ago I was skeptical. Burt Rutan does it again! -- Brian Lloyd 6501 Red Hook Plaza brianl@lloyd.com Suite 201 http://www.lloyd.com St. Thomas, VI 00802 +1.340.998.9447 (voice) +1.360.838.9669 (fax) There is a time to laud one's country and a time to protest. A good citizen is prepared to do either as the need arises. ________________________________ Message 16 ____________________________________ Time: 03:01:21 PM PST US Subject: AeroElectric-List: Automotive Landing Lights? From: "Bordelon, Greg" --> AeroElectric-List message posted by: "Bordelon, Greg" I want to add more landing/taxi lighting to my aircraft. I went down to Pep Boys and purchased several auto headlights, driving lights, and fog lights. I conducted some experiments at night and found there is huge difference in illumination pattern among the lights I purchased. I also found that using a combination high & low beam head light worked very well when BOTH elements were turned on. Anyone on the list have any experience using high/low beam simultaneously? I'm a bit concerned that having both elements glowing will significantly shorten the life of the bulb to only a few hours. Any experiences out there? Thx ________________________________ Message 17 ____________________________________ Time: 03:11:08 PM PST US From: "Larry McFarland" Subject: AeroElectric-List: wiring security --> AeroElectric-List message posted by: "Larry McFarland" Hi guys, On advice, I began the task of progressively redoing tie-ties that have put both singular or grouped wires directly against metal. This typically required cutting one and replacing it with 3 tie-ties to make two grips and a standoff. It looked good, but seems to offer more motion to the wires thru engine vibration acting against the wires. One has to consider which is worse, "movement and fatigue" or "wear by tie-tie clamping wires against a surface and cutting insulation". I've not seen much discussion of this on the Matronics pages. If there are opinions or "rules" on these considerations beyond the usual Adel clamps, etc I'd be interested to hear about this area where wires traverse the smooth boundarys of the motor mount and firewall. Larry McFarland - 601HDS ________________________________ Message 18 ____________________________________ Time: 03:29:47 PM PST US From: "Terry Watson" Subject: RE: AeroElectric-List: wiring security --> AeroElectric-List message posted by: "Terry Watson" Along the same lines, I have been wondering about using short lengths of vinyl tubing to pad the wires from the plastic wire ties. It's easy to do. Just cut a short length, split it lengthwise, and put it around the bundle of wires. Terry -----Original Message----- From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com]On Behalf Of Larry McFarland Subject: AeroElectric-List: wiring security --> AeroElectric-List message posted by: "Larry McFarland" Hi guys, On advice, I began the task of progressively redoing tie-ties that have put both singular or grouped wires directly against metal. This typically required cutting one and replacing it with 3 tie-ties to make two grips and a standoff. It looked good, but seems to offer more motion to the wires thru engine vibration acting against the wires. One has to consider which is worse, "movement and fatigue" or "wear by tie-tie clamping wires against a surface and cutting insulation". I've not seen much discussion of this on the Matronics pages. If there are opinions or "rules" on these considerations beyond the usual Adel clamps, etc I'd be interested to hear about this area where wires traverse the smooth boundarys of the motor mount and firewall. Larry McFarland - 601HDS ________________________________ Message 19 ____________________________________ Time: 05:04:43 PM PST US Subject: Re: AeroElectric-List: Automotive Landing Lights? From: lm4@juno.com --> AeroElectric-List message posted by: lm4@juno.com Greg, I'll answer this just to draw more answers. Sure, the heat will double. But you'll only be using them for a few minuts so I doubt that it will make any difference. Did you test for pattern on any halogen lamps ? If so, what do you think ? Larry Mac Donald Rochester N.Y. do not archive On Mon, 21 Jun 2004 17:00:42 -0500 "Bordelon, Greg" writes: > --> AeroElectric-List message posted by: "Bordelon, Greg" > > > I want to add more landing/taxi lighting to my aircraft. I went down > to > Pep Boys and purchased several auto headlights, driving lights, and > fog > lights. I conducted some experiments at night and found there is > huge > difference Any experiences out there? Thx ________________________________ Message 20 ____________________________________ Time: 06:33:03 PM PST US From: Benford2@aol.com Subject: Re: AeroElectric-List: Automotive Landing Lights? --> AeroElectric-List message posted by: Benford2@aol.com In a message dated 6/21/2004 4:02:42 PM Mountain Daylight Time, gbordelon@hess.com writes: > > I want to add more landing/taxi lighting to my aircraft. I went down to > Pep Boys and purchased several auto headlights, driving lights, and fog > lights. I conducted some experiments at night and found there is huge > difference in illumination pattern among the lights I purchased. I also > found that using a combination high & low beam head light worked very > well when BOTH elements were turned on. Anyone on the list have any > experience using high/low beam simultaneously? I'm a bit concerned that > having both elements glowing will significantly shorten the life of the > bulb to only a few hours. Any experiences out there? Thx Naw. The bulb will last a long time but you will be pulling some serious amps to run them both at the same time. You want to use spot bulbs for the landing light and fog/driving lights for taxi lights. All ya got to do is look at the lens, that determines the light pattern. Ben Haas N801BH. ________________________________ Message 21 ____________________________________ Time: 07:06:26 PM PST US From: "Paul Messinger" Subject: Re: AeroElectric-List: engine hot starting and more on batteries --> AeroElectric-List message posted by: "Paul Messinger" ----- Original Message ----- From: "Brian Lloyd" > > I am not pushing Odyessy, but they only cost around double the Panasonic and > > still well under $100 delivered and have the ability to sit around with NO > > need for a float charger to keep it topped off like the Panasonic does. > > All batteries have some level of self discharge. The lead alloy can reduce that to some extent but you can't eliminate that. The warmer the battery, the faster the level of self discharge. Keeping a battery on a proper float charge is a safe thing to do. YMMV. Look at the self discharg times for the Panasonic vs the good ones. Sure its temp dependent but we are looking at nearly a order of magnitude lower self discharge rate; one that eleminates in most cases, any need for battery float chargers that the Panasonic types require. At 25C and 12 months the panasonic has LOST 36% of its charge. Odyssey states at 25C it can be stored for 2 YEARS before needinmg to be recharged. I do not remember the data on the Optima but its at least a year. I did a test on one of my Odyssey batterys and it needed 15 min at one amp after 9 months to tpo off using their recommended charger. The next day the battery indicated 100% charge per their resting V table using a 0.025% accurate meter. A Panasonic needed over 12 hours to fully charge with the same charger etc. Not needing to use a float charger is nice! WHY do it if its not required and really does nothing much. Warm feeling a suppose :-) >> > Get a $50 adjustable reg and mount it near the battery (for temperature > > compensation) and be done with it. Set the V on the low side of the range > > and you are likely to get battery life that exceeds the reasonable battery > > replacement cycle time. > > I don't completely agree with this as the battery may be at a different temperature than its surroundings. The only way to measure battery temperature for sure is to actually attach the measuring device to the battery. Remember that the battery is going to get warm during charge and it is going to be warmer than the surrounding air. Who knows what the current through the VR is going to do to the temperature of the VR. I can safely say that the two of them will *NOT* be at the same temperature unless the VR is firmly attached to the battery. How close do you need to be??? Panasonic suggests its a large temp diff is only a small gain in battery life. 30 deg c increases life 5%. > > Also, what is the temperature compensation curve in these cheap regulators? Does it match what the battery requires? I think not. I bet it is just something like a reduced voltage drop across a couple of diodes in the VR reference circuit, not exactly tailored to the voltage settings required for a proper battery charge. Sorry but you need to do your homework on this one. The regulator chip is specially designed to match closely the average battery temp vs V requirements. One key feature of the regulators is the ability to match the voltage needs VS temp. If it bothers you so much use heat sink compound and mount the reg to the side of the battery :-) > > Use the proper low cost regulator and get both temp compensation and voltage > > set for under $50. and no need for extra temp sensor. > > Again, I don't believe that will work. Thats your opinion and you have every right to it. > > The B&C reg is nearly $300 with the temp sensor option. lets see, 6X the > > cost and no ability to adjust voltage. WHY go there?? The SAR 3 is even more > > expensive for what. Longer than what life. Likely longer than I would ever > > need but that is an individual decision. Bob suggests panasonic replacement > > on an annual basis. This coupled with the average under 100 flight hours per > > year makes sense to me. > > > > So I have Odyssey batteries in the cabin and the reg is temperature > > compensated V set type. > > > > Two batteries and a regulator for around $200 total. Expected annual cost > > $50 based on a biannual battery replacement. > > Certainly that is a way to go. But now many people on this list now have a better idea how all this works and can make a choice for themselves? How many people on this list are building beautiful works of mechanical art and want to do everything as perfectly as possible? Achieving perfection even in the small things can be a reward in and of itself. Please don't run that down. Yes, but for the Nth time you have failed to respond with ANY facts in regard to how much longer or how much better. Longer and better are not enough for ANY informed decision. If it makes a 8 year battery into a 10 year one I could care less. If it makes a 3 year battery into a 1/2 year battery I am interested. I suspect its the former and demonstrability not the latter. > > Also I disagree with Bob's position on putting the fresh battery in the main > > position. I want to know what the battery capacity is in an emengency so the > > new battery is in the backup position. And yes I do load test annually as > > that is so simple to do with NO extra equipment other than a clock :-) > > Perhaps. OTOH, it is the main battery that gets all the use. Yes and if the backup battery has "lost its will to live" and lets you down when you need it, what then. A backup is worse than useless if its not reliable. MY position is if its not good enough for prime time its not anything I want as backup. This is a general comment but in my case the backup is really in use all the time as I have a electrically dependent engine and both systems must be on and ready for instant prime time. Some what different than mag powered VFR day flying. Paul ________________________________ Message 22 ____________________________________ Time: 07:59:59 PM PST US From: "Paul Messinger" Subject: Re: AeroElectric-List: Battery data and etc --> AeroElectric-List message posted by: "Paul Messinger" ----- Original Message ----- From: "Brian Lloyd" Subject: Re: AeroElectric-List: Battery data and etc > --> AeroElectric-List message posted by: Brian Lloyd > > Paul Messinger wrote: > > > --> AeroElectric-List message posted by: "Paul Messinger" > > > >>Now that we have traded ideas and insults, may I buy you a beer at OSH so > > > > we can discuss battery and charging technology at greater length? > > > >>-- > >>Brian Lloyd > > > > > > Well done > > Well, getting all pissy at each other doesn't really solve anything, does it. Drinking beer after a day of flying or playing with airplanes is far more pleasant. I Guess I cannot win no matter what I do. I was being complimentary to your nice reply. Paul ________________________________ Message 23 ____________________________________ Time: 07:59:59 PM PST US From: "Paul Messinger" Subject: AeroElectric-List: Cont VS Bendix injection systems --> AeroElectric-List message posted by: "Paul Messinger" I can hardly ask others to be specific when I am not; so here are the details on the two specific injection systems and why one is so much better in hot starting. This from a 1971 version of the A&P Powerplant Handbook. I recognize that not all, in fact most (many?) Cont engines used the Bendix system. My S35 used the Cont system :-) My MK21 Exec had the Bendix system :-( First the basics of each system. I am paraphrasing the book. The Bendix RSA system. It uses a venturi/regulator setup to measure both the ram air pressure and venturi suction with a somewhat complex dual diaphram ball valve assy to meter fuel. (The presence of the venturi leads to slightly lower manifold pressure and slightly more possibility of induction system iceing .) The metered and unmetered fuel is then sent to the Fuel metering section where the Throttle linkage and mixture linkage combine in a metering assy. From there the fuel is sent to the Flow divider usually at the top center of the engine case where small lines radiate out to each cyl. The fuel in these lines go thru a flow restrictor (small hole) and into the Cyl head. From the fuel pump on, there is no vapor or fuel return line back to the tank. The system pressure is low to medium (compared to the modern auto injected engine) between the Inlet Regulator assy to the Fuel metering section and essentially zero when there is no flow (engine stopped) in the small feed lines. It's the small feed lines that boil and flood into the cyl causing excess fuel before the Hot start is attempted. From the inlet regulator section to the distribution section the fuel is hot and ready to vaporize if the pressure is low enough. With no way to replace this fuel the hot start adds more fuel and vapor to an already too rich mixture and the hot start attampt continues until all this hot fuel is purged. But the engine compartment is hot and the fuel in the engine compartment has no way to be replaced and thus must be purged thru the system with cool fuel before reliable starting can occur. Thus the sometimes long process of getting a start under hot conditions. The Cont system, at least as described in the ref manual and on my S35 acft (Cont IO520B) Very differnt concept. The engine driven pump is a Positive displacement pump and is able to use an Aux pump with no change in performance. (no concern about HI or LOW pump setting or changes in mixture with aux on or off) The pump output pressure is independent of altitude or ambient air conditions. The pump has a built in bypass as well as a builtin Vapor seperator and fuel return to the tank requirement. The aux pump can flush and replace hot fuel with cool fuel. The Fuel air control unit contains the throttle assy and NO venturi or other air flow restrictions. (Slightly lower risk of icing and slightly higher manifold pressure) The fuel control assy has two series connected spool valves. One is linkled to the throttle linkage and one to the mixture control. Excess fuel is returned to the fuel pump and fuel is passed thru this assy even when the mixture is in idle cutoff. This permits the aux pump to flush hot fuel all the way to the output of this assy. Finally there is the flow divider unit which is essentially the same as the Bendix system. Conclusions: Bendix system cannot flush the fuel past the firewall as there is no fuel return setup. In a hot start condition a significant amount of fuel must be purged from the system and out the exhaust before the engine can run. In the Cont system the aux pump can purge all the fuel except the small amount in the line to and the lines from the flow divider. This is estimated to be 80% or more of the total fuel in the engine compartment (there is really only a very small amount of fuel in the non purgable part of the system). Thus the Cont design greatly reduces the amount of hot fuel that must be disposed of in a hot start. I have extensive experience in the two systems and I would never, by choice fly witrh an engine, using the Bendix system or at least as described above. The MK21 was on occasion nearly imposable to hot start and the S35 was a dream and easy to hot start. In flight; I found leaning etc on climb etc (in single pilot IFR) no more effort in either case. Both started cold equally well. Hot start problems made the Bendix system unacceptable to me. I sometimes wonder why so many just assume its part of the beast and do not rise up and insist it be fixed. Having experenced both I cannot understand how its put up with. Paul ________________________________ Message 24 ____________________________________ Time: 09:18:05 PM PST US Subject: RE: AeroElectric-List: Automotive Landing Lights? From: "Bordelon, Greg" --> AeroElectric-List message posted by: "Bordelon, Greg" My panel space is limited and I wish to eliminate installing a switch for the taxi light. I plan to wire up the low beam element with the high beam element (in parallel) together. I want to install one switch, off in down position, wig wag in middle position, and lights on in up position. The manufacture states the high beam element is 55 watts and the low beam element is 45 watts. This is 100 watts collectively. Ohms law says that 100 watts divided by 14 volts is about 7 amps of current flow. Since I want to install two lamps, this will give a total current flow of 14 amps. I see no problem with this. In my car, the elements seem to go for years. My concern was running both elements simultaneously would reduce the life to a few hours. I guess I will have to attach one to my battery and battery charger and let it glow for a few days to conduct a test. Of the five different lights I bought (and returned), I found that just because two lamps are round it does not mean their lighting pattern will be the same. Minor differences in the reflector shape plays a major role in light pattern. I found these to work very well, especially when you replace the 55 watt bulb with a 100 watt bulb. http://www.autoanything.com/products/product_sp.aspx?p_id=1333&se=hella_ light_optilux_2500_angel_eye_kit Also check out http://www.piaa.com/Bulbs/Bulbs-H4.html So, is there anyone out there that has ganged the elements together? Thanks for the responses. -----Original Message----- From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of lm4@juno.com Subject: Re: AeroElectric-List: Automotive Landing Lights? --> AeroElectric-List message posted by: lm4@juno.com Greg, I'll answer this just to draw more answers. Sure, the heat will double. But you'll only be using them for a few minuts so I doubt that it will make any difference. Did you test for pattern on any halogen lamps ? If so, what do you think ? Larry Mac Donald Rochester N.Y. do not archive On Mon, 21 Jun 2004 17:00:42 -0500 "Bordelon, Greg" writes: > --> AeroElectric-List message posted by: "Bordelon, Greg" > > > I want to add more landing/taxi lighting to my aircraft. I went down > to > Pep Boys and purchased several auto headlights, driving lights, and > fog > lights. I conducted some experiments at night and found there is > huge > difference Any experiences out there? Thx == == == == ________________________________ Message 25 ____________________________________ Time: 10:49:19 PM PST US Subject: AeroElectric-List: King KSG100 slaved Gyro From: james.k.glindemann@exxonmobil.com 7, 2002) at 06/22/2004 12:46:03 AM --> AeroElectric-List message posted by: james.k.glindemann@exxonmobil.com I have acquired a King Directional Gyro Model No KSG100 and need the connector pin out information. Does anybody out there have it? thanks James K Glindemann