---------------------------------------------------------- AeroElectric-List Digest Archive --- Total Messages Posted Thu 09/29/05: 24 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 04:26 AM - Re: ND two-lead alternator question () 2. 05:21 AM - Re: ND two-lead alternator question (Mickey Coggins) 3. 06:25 AM - Re: Noise Clarification (Robert L. Nuckolls, III) 4. 06:33 AM - Re: ND two-lead alternator question (Robert L. Nuckolls, III) 5. 07:10 AM - Re: ND two-lead alternator question (PWilson) 6. 08:45 AM - Re: Solid State Gyros (Jon Goguen) 7. 08:49 AM - Re: ND two-lead alternator question (Mickey Coggins) 8. 10:02 AM - Re: Solid State Gyros (Earl_Schroeder) 9. 10:04 AM - Re: ND two-lead alternator question (Ken) 10. 11:00 AM - Re: Solid State Gyros (SteinAir, Inc.) 11. 11:32 AM - Re: Solid State Gyros (Phil Birkelbach) 12. 11:41 AM - Re: ND two-lead alternator question (Mickey Coggins) 13. 12:01 PM - Re: Solid State Gyros (Matt Prather) 14. 01:11 PM - Re: Solid State Gyros (Joseph Larson) 15. 01:56 PM - Re: ND two-lead alternator question (Robert L. Nuckolls, III) 16. 03:11 PM - Re: ND two-lead alternator question (Robert L. Nuckolls, III) 17. 04:02 PM - Re: Solid State Gyros (Jon Goguen) 18. 04:09 PM - VANs ND Alternator wiring (Carl Morgan) 19. 06:51 PM - Re: ND two-lead alternator question (Frank Stringham) 20. 07:26 PM - OVP failure consequent to VR failure (Rodney Dunham) 21. 07:27 PM - OVP failure consequent to VR failure (Rodney Dunham) 22. 07:41 PM - Re: ND two-lead alternator question (N1deltawhiskey@aol.com) 23. 08:51 PM - Re: Solid State Gyros (GMC) 24. 10:18 PM - Re: ND two-lead alternator question (Mickey Coggins) ________________________________ Message 1 _____________________________________ Time: 04:26:57 AM PST US From: Subject: Re: AeroElectric-List: ND two-lead alternator question --> AeroElectric-List message posted by: >Bob N wrote: Again, like the so called "OV Protection" built into the regulator > chip, there are reliability issues with using the same > chip to annunciate non-operation as well as control an alternator. I agree you should have a separate Lo/Hi voltage indicator but not for the reasons you state. You also address ND alternator reliability for which you have no knowledge of and should focus on facts and not your opinion. -The chance of an indication failure and alternator failure (of the kind that only exist in your dreams Bob) at the same time is unlikely. The lamp driver and detection is separate from the voltage regulator, even if the function is contained in the same chip. It is possible that a rare fault will happen in the first place and even more rare the indicator fails at the same time. The bulb is more likely to fail, but you can check it every time you turn your electrical system on before cranking the engine over. The idiot light will glow just like your car. -Second, the so called OV protection is more sophisticated than a so called crow bar.Also being on-board the alternator is reacts quicker and more precisely (despite what Bob says). -Last the indicator not only indicates charge (or lack of charge) but also indicates faults, like loss of remote sense, on those models so equipped. Unlike most simple external "so called" voltage regulators, there are logic, control and fault detections incorporated in the ND alternators internal VR. The reason I use the ND indicator light is because that is the way real smart engineers at ND designed the alternator to be wired. The reason I also have a Hi/Lo volt indicator is my system management engine indicator instrument already came with it. I am a belt and suspenders kind of guy. If you have a non electrical dependent engine and panel or are VFR, you could get away with extra Hi/Lo voltage indication. Even if your existing instrumentation does not have a Hi/Lo indicator, a discrete module is a small, light weight device. (PS: for the two wire ND's the IGN does provide voltage sense. In aircraft wiring that is very compact where the alternator and battery are close, the remote sense is not needed, but if you have it use it; it goes to the battery.) Bob, you are talking about reliability issues, and you have no idea what you are talking about. You said you have an engineering degree and understand failure mode analysis and in particular those of the IC chips in ND alternators? Where did you go to school and what degree did you get? I went to LSU for under grad and UW for grad school. What reliability data do you have? I will admit my info is anadotical, but it is backed up by conversations with Nippon Denso engineers, auto industry electrical service experts and the National Transportation Safety data base that tracks reliability of all aspects of automobiles, including electrical charging systems (alternators). Since there a millions ND alternators in service with no record of recalls, consumer complaint or safety related issues, such as fires, I would say that is pretty good statistics, not to mention the millions of ND alternators in industrial equipment, going 24/7 for year after year with no problem. What reliability info do you have? I know everyone gives Paul crap about not showing data, lets see your ND alternator reliability data, please. (facts: model, place, failure mode, indications and affect of failure) George ATP, CFI(I)(ME), MSME, RV-4/7/B757/767 >From: "Robert L. Nickolas, III" >Subject: Re: ND two-lead alternator question > >--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" >Do you have a low voltage warning light? Again, like >the so called "OV Protection" built into the regulator >chip, there are reliability issues with using the same >chip to annunciate non-operation as well as control an alternator. >A battery voltage less than 13.0 volts says it all and >this is best accomplished with a system that gets pre-flight >tested and is independent of the alternator or its regulator. >Bob . . . --------------------------------- Click here to donate to the Hurricane Katrina relief effort. ________________________________ Message 2 _____________________________________ Time: 05:21:30 AM PST US From: Mickey Coggins Subject: Re: AeroElectric-List: ND two-lead alternator question --> AeroElectric-List message posted by: Mickey Coggins > (PS: for the two wire ND's the IGN does provide voltage sense. In > aircraft wiring that is very compact where the alternator and battery > are close, the remote sense is not needed, but if you have it use > it; it goes to the battery.).... > I will admit my info is anadotical, > but it is backed up by conversations with Nippon Denso engineers, > auto industry electrical service experts and the National > Transportation Safety data base that tracks reliability of all > aspects of automobiles, including electrical charging systems > (alternators). George, Thanks for the information about the IG terminal providing voltage sense. Do you know where I can get some technical details on the two wire ND alternator that I have? http://www.rv8.ch/article.php?story=2004112513263691 Basically I'd like to know the exact functions of the IG and L terminals. I've been getting conflicting information from various sources, and I'd love to know what the designers say it does. I've written to them, but so far no response. Thanks, Mickey -- Mickey Coggins http://www.rv8.ch/ #82007 finishing do not archive ________________________________ Message 3 _____________________________________ Time: 06:25:43 AM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Noise Clarification --> AeroElectric-List message posted by: "Robert L. Nuckolls, III" At 05:16 PM 9/28/2005 -0700, you wrote: >--> AeroElectric-List message posted by: "Roger Evenson" > > >Bob: Reviewing cha. 16 on noise, I'm trying to understand the following >apparent contradiction: >One recommendation is to avoid the 'bad hair' look, and instead run wires >bundled close together as long as possible, with short breakouts. Yet, >two of the four listed noise propagation modes (magnetic and >electrostatic) result from wires in close parallel proximity. > >Care to comment? Not all wires are carriers of potential antagonistic stimulus, not all wires are potential potential victims to such stimulus. One needs to identify both potential antagonists and victims and apply such measures only to those wires that will promote happy coexistence in common wire bundles. The majority of wires require no special attention. The few systems where there is potential for detrimental cross-talk, we use shields, twisted pairs, and take care to avoid ground loops with carefully considered ground systems. These actions make it possible for virtually all wiring to be neatly bundled with minimal risk of degraded performance. Bob . . . ________________________________ Message 4 _____________________________________ Time: 06:33:18 AM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: ND two-lead alternator question --> AeroElectric-List message posted by: "Robert L. Nuckolls, III" At 02:20 PM 9/29/2005 +0200, you wrote: >--> AeroElectric-List message posted by: Mickey Coggins > > > > (PS: for the two wire ND's the IGN does provide voltage sense. In > > aircraft wiring that is very compact where the alternator and battery > > are close, the remote sense is not needed, but if you have it use > > it; it goes to the battery.).... > > > I will admit my info is anadotical, > > but it is backed up by conversations with Nippon Denso engineers, > > auto industry electrical service experts and the National > > Transportation Safety data base that tracks reliability of all > > aspects of automobiles, including electrical charging systems > > (alternators). The world is besot with experts, no-value-added bureaucrats and purveyors of myth all of whom could be easily and accurately replaced in this case by a schematic of the regulator chip or the repeatable experiment as described below . . . >George, > >Thanks for the information about the IG terminal providing >voltage sense. Do you know where I can get some technical >details on the two wire ND alternator that I have? > > http://www.rv8.ch/article.php?story=2004112513263691 > >Basically I'd like to know the exact functions of the IG and L >terminals. I've been getting conflicting information from >various sources, and I'd love to know what the designers say >it does. I've written to them, but so far no response. Wire it up, run the alternator with solid wire in the feeders to IG and L, then put a diode in series with each wire one at a time. If insertion of the diode causes bus voltage to rise by about 0.6 volts, then that wire has been demonstrated to be a sense lead for the purpose of providing more accurate control of bus voltage. Bob . . . ________________________________ Message 5 _____________________________________ Time: 07:10:32 AM PST US From: PWilson Subject: Re: AeroElectric-List: ND two-lead alternator question --> AeroElectric-List message posted by: PWilson HI George. Do you have any knowledge about the Nissan recall to replace over 100000 alternators? I just wonder who provided the alternator that had internal shorts and cause fires. Regards, Paul W ============= At 05:25 AM 9/29/2005, gmcjetpilot wrote: >-------snip-------- >Since there a millions ND alternators in service with no record of >recalls, consumer complaint or safety related issues, such as fires, >I would say that is pretty good statistics, not to mention the >millions of ND alternators in industrial equipment, going 24/7 for >year after year with no problem. -----snip----------- >George ATP, CFI(I)(ME), MSME, RV-4/7/B757/767 ________________________________ Message 6 _____________________________________ Time: 08:45:42 AM PST US From: Jon Goguen Subject: Re: AeroElectric-List: Solid State Gyros --> AeroElectric-List message posted by: Jon Goguen I looked at the TruTrak ADI at Oshkosh, and came away very concerned that it's a potentially dangerous device. If you look at their ads, you'l see that they describe the pitch information provided as "gyro enhanced vertical speed". As I understood the description of this function from the TruTrak reps at Oshkosh, it differs from the pitch info provided by a classical ADI in an important way: when the ship changes attitude, you get an immediate indication of a change in pitch. However, once a new stable attitude is established the pitch indicator moves back to the horizon. Essentially, the device indicates something more akin to the derivative of pitch than pitch per se. Maybe there are some circumstances under which this is a good thing, but its not clear to me what they might be. If you don't have a horizon outside the ship, you cannot depend the TruTrak ADI to give an absolute pitch indication. Jon Jon Goguen jon.goguen@umassmed.edu Central Massachusetts Kitfox Series V Rotax 912S / N456JG (reserved) Complete except for electrics and avionics On Sep 28, 2005, at 8:59 PM, Fiveonepw@aol.com wrote: > --> AeroElectric-List message posted by: Fiveonepw@aol.com > > Did you look at stuff by PCFlightSystems? Maybe they have something > you can > use. I use their PDA based EFIS/GPS Nav stuff as my main PFD/NAV > (VFR) and it > works quite nicely... > > http://pcflightsystems.com/ > > Mark Phillips, RV-6A N51PW Columbia TN > > ________________________________ Message 7 _____________________________________ Time: 08:49:17 AM PST US From: Mickey Coggins Subject: Re: AeroElectric-List: ND two-lead alternator question --> AeroElectric-List message posted by: Mickey Coggins > Wire it up, run the alternator with solid wire in the > feeders to IG and L, then put a diode in series with > each wire one at a time. If insertion of the diode causes > bus voltage to rise by about 0.6 volts, then that wire > has been demonstrated to be a sense lead for the purpose > of providing more accurate control of bus voltage. Thanks for the info. I just did this, and I didn't see any difference with or without the diode. I used a 1N 4004 diode. My battery only voltage was about 12.9v, and when cranking on the alternator with a 3000rpm electric hand drill, the voltage went up to about 14.3v within about 10-15 seconds. I could feel the load on the drill start out high, then gradually taper off. I'm measuring the voltage across the battery terminals. I agree that a schematic of this alternator's voltage regulator would be great! Thanks again for your help. Mickey -- Mickey Coggins http://www.rv8.ch/ #82007 finishing do not archive ________________________________ Message 8 _____________________________________ Time: 10:02:31 AM PST US From: Earl_Schroeder Subject: Re: AeroElectric-List: Solid State Gyros --> AeroElectric-List message posted by: Earl_Schroeder Jon Goguen wrote: >--> AeroElectric-List message posted by: Jon Goguen > > As I understood the description of this >function from the TruTrak reps at Oshkosh, it differs from the pitch >info provided by a classical ADI in an important way: when the ship >changes attitude, you get an immediate indication of a change in pitch. > However, once a new stable attitude is established the pitch indicator >moves back to the horizon. > Jon, Did the rep confirm this or is that your assumption? Since I am considering a purchase, I'd really like to know. Thanks, Earl ________________________________ Message 9 _____________________________________ Time: 10:04:55 AM PST US From: Ken Subject: Re: AeroElectric-List: ND two-lead alternator question --> AeroElectric-List message posted by: Ken Mickey I love to see a real test - thank you. May I ask if you tried the diode with the white band end towards the alternator? That would give the IG wire the opportunity to be at 0.6 volts less than the battery assuming a little current flow into the IG connection. With the diode the other way around it might just be defaulting to regulating based on the voltage at the output terminal. Ken Mickey Coggins wrote: >--> AeroElectric-List message posted by: Mickey Coggins > > > >> Wire it up, run the alternator with solid wire in the >> feeders to IG and L, then put a diode in series with >> each wire one at a time. If insertion of the diode causes >> bus voltage to rise by about 0.6 volts, then that wire >> has been demonstrated to be a sense lead for the purpose >> of providing more accurate control of bus voltage. >> >> > >Thanks for the info. I just did this, and I didn't see >any difference with or without the diode. I used a >1N 4004 diode. My battery only voltage was about 12.9v, >and when cranking on the alternator with a 3000rpm >electric hand drill, the voltage went up to about 14.3v >within about 10-15 seconds. I could feel the load on >the drill start out high, then gradually taper off. >I'm measuring the voltage across the battery terminals. > >I agree that a schematic of this alternator's voltage >regulator would be great! > >Thanks again for your help. > >Mickey > > > ________________________________ Message 10 ____________________________________ Time: 11:00:32 AM PST US From: "SteinAir, Inc." Subject: RE: AeroElectric-List: Solid State Gyros --> AeroElectric-List message posted by: "SteinAir, Inc." Not to sound harsh here, but I'm afraid your conclusion that an instrument is "potentially dangerous" is rather dubious not having flown behind one. Talk to the guys who've been flying behind these things (Yes, in IFR), and they'll tell you it's superior to the old gyro AI in almost every way. It's hard to get a very good indication of what it does from their ads and on a bench, but fly behind one and you'll come away understanding how well it does work. This subject get's re-hashed regularly, and a search of the archives on the RV list will give you a load of info on it. There are several reasons it's actually better. Pitch combined with direction is far better.....with a traditional gyro, you can easily get it to indicate a "nose high" attitude whilst the ship is descending, not so with an ADI. Get slow, and the thing will tell you. Get upside down or in a very unusual attitude and the thing tells you which way to move the stick to correct it. Do a loop with it (the ADI) and it'll still be nuts on. Do a loop with your RC Allen or Sigma-Tek and they will go nuts. "Absolute Pitch Indication" isn't always worth as much as you might think (like the example above of descending with your nose high). Anyway, no flames intended here. It just seems to regularly come up lately, and there are two distinct camps of people's opinions when it comes to the ADI. Love it or hate it.....and.....from what I've seen those opinions are almost 100% tied to whether or not the person really knows how they work and has experienced them, or those who've flown behind one and those who haven't. Don't get me wrong, I'm as old school as they come with this stuff, but I try to keep an open mind before I make a final judgement on something, especially something designed by Younkin (who's forgotten more about this stuff than most of us will ever know). Old practices and procedures are hard to change, but some of these newfangled gizmos are in reality quite good compared to the old spinning metal mass gyros. Before you think that I'm being biased, I'll say that I have both in my airplane. I have the old vac gyros as well as the new digital stuff (Dynon and TruTrak). Guess which I like better?! I also was skeptical, but now I'm entirely convinced the new stuff is the way to go. Just my 2 cents as usual! Cheers, Stein. > -----Original Message----- > From: owner-aeroelectric-list-server@matronics.com > [mailto:owner-aeroelectric-list-server@matronics.com]On Behalf Of Jon > Goguen > Sent: Thursday, September 29, 2005 10:44 AM > To: aeroelectric-list@matronics.com > Subject: Re: AeroElectric-List: Solid State Gyros > > > --> AeroElectric-List message posted by: Jon Goguen > > > I looked at the TruTrak ADI at Oshkosh, and came away very concerned > that it's a potentially dangerous device. If you look at their ads, > you'l see that they describe the pitch information provided as "gyro > enhanced vertical speed". As I understood the description of this > function from the TruTrak reps at Oshkosh, it differs from the pitch > info provided by a classical ADI in an important way: when the ship > changes attitude, you get an immediate indication of a change in pitch. > However, once a new stable attitude is established the pitch indicator > moves back to the horizon. Essentially, the device indicates something > more akin to the derivative of pitch than pitch per se. Maybe there > are some circumstances under which this is a good thing, but its not > clear to me what they might be. If you don't have a horizon outside > the ship, you cannot depend the TruTrak ADI to give an absolute pitch > indication. > > Jon > > Jon Goguen > jon.goguen@umassmed.edu > Central Massachusetts > Kitfox Series V Rotax 912S / N456JG (reserved) > Complete except for electrics and avionics > On Sep 28, 2005, at 8:59 PM, Fiveonepw@aol.com wrote: ________________________________ Message 11 ____________________________________ Time: 11:32:58 AM PST US From: Phil Birkelbach Subject: Re: AeroElectric-List: Solid State Gyros --> AeroElectric-List message posted by: Phil Birkelbach I sent Jon's note to TruTrak. I'll report when I get an answer from them. I suspect that it is a missunderstanding on how the unit determines what the pitch is. My guess is that it is integrating an acceleromter at the same time that it is integrating a rate gyro to determine the pitch to show. My Dynon has some similar features but it doesn't give wrong information it just determines the information with a little different methods than the mechanical ADI's. We'll see what TruTrak has to say. Godspeed, Phil Birkelbach - Houston Texas RV-7 N727WB - Phase I http://www.myrv7.com Earl_Schroeder wrote: >--> AeroElectric-List message posted by: Earl_Schroeder > > >Jon Goguen wrote: > > > >>--> AeroElectric-List message posted by: Jon Goguen >> >> As I understood the description of this >>function from the TruTrak reps at Oshkosh, it differs from the pitch >>info provided by a classical ADI in an important way: when the ship >>changes attitude, you get an immediate indication of a change in pitch. >> However, once a new stable attitude is established the pitch indicator >>moves back to the horizon. >> >> >> >Jon, >Did the rep confirm this or is that your assumption? Since I am >considering a purchase, I'd really like to know. Thanks, Earl > > > > ________________________________ Message 12 ____________________________________ Time: 11:41:06 AM PST US From: Mickey Coggins Subject: Re: AeroElectric-List: ND two-lead alternator question --> AeroElectric-List message posted by: Mickey Coggins Hi Ken, Yes, the white band was towards the alternator. :-) Mickey Ken wrote: > --> AeroElectric-List message posted by: Ken > > Mickey > I love to see a real test - thank you. > May I ask if you tried the diode with the white band end towards the > alternator? > That would give the IG wire the opportunity to be at 0.6 volts less than > the battery assuming a little current flow into the IG connection. With > the diode the other way around it might just be defaulting to regulating > based on the voltage at the output terminal. > Ken > > > Mickey Coggins wrote: > > >>--> AeroElectric-List message posted by: Mickey Coggins >> >> >> >> >>> Wire it up, run the alternator with solid wire in the >>> feeders to IG and L, then put a diode in series with >>> each wire one at a time. If insertion of the diode causes >>> bus voltage to rise by about 0.6 volts, then that wire >>> has been demonstrated to be a sense lead for the purpose >>> of providing more accurate control of bus voltage. >>> >>> >> >>Thanks for the info. I just did this, and I didn't see >>any difference with or without the diode. I used a >>1N 4004 diode. My battery only voltage was about 12.9v, >>and when cranking on the alternator with a 3000rpm >>electric hand drill, the voltage went up to about 14.3v >>within about 10-15 seconds. I could feel the load on >>the drill start out high, then gradually taper off. >>I'm measuring the voltage across the battery terminals. >> >>I agree that a schematic of this alternator's voltage >>regulator would be great! >> >>Thanks again for your help. >> >>Mickey >> -- Mickey Coggins http://www.rv8.ch/ #82007 finishing do not archive ________________________________ Message 13 ____________________________________ Time: 12:01:26 PM PST US Subject: Re: AeroElectric-List: Solid State Gyros From: "Matt Prather" --> AeroElectric-List message posted by: "Matt Prather" It seems very surprising that the ADI works exactly as you described.. Instead, I suspect that as long as the airplane is stabilized in a descent (negative vertical speed), the display will indicate a nose-down attitude, and when stabilized in a climb, it will display a nose-up attitude. It looks like the device uses VSI information to cancel slow-term gyro drift. The only weird thing about this behavior is that there probably isn't a pitch indication difference between stabilized level flight (vertical speed=0) whether at Vmo or Vs. Say you're are running flat out because ATC told you to keep your speed up. The attitude indicator shows level flight. Then they tell you to enter a hold, you decide to slow down (to save gas), so you pull power back, and start to roll in nose-up trim to maintain altitude. Initially, the ADI correctly indicates this higher pitch attitude. Finally, you get down to loiter speed and the nose is actually at a much steeper pitch attitude than when at Vmo. Once stabilized at the new pitch/speed combination, the ADI will slowly indicate that the nose is returning to a level atttitude.. That's the VSI 'enhanced' feature. I don't think this is likely to cause control problems, though it is especially important to keep the Airspeed Indicator in your scan. I guess there is one other weird behavior.. If you take on a load of ice, airspeed will suffer and eventually you won't be able to maintain altitude, even with the nose pitched up to best L/D (Vy) attitude. So you start to descend. I suspect the ADI will indicate a nose down attitude even though you are actually pitched up. Regards, Matt- > --> AeroElectric-List message posted by: Jon Goguen > > > I looked at the TruTrak ADI at Oshkosh, and came away very concerned > that it's a potentially dangerous device. If you look at their ads, > you'l see that they describe the pitch information provided as "gyro > enhanced vertical speed". As I understood the description of this > function from the TruTrak reps at Oshkosh, it differs from the pitch > info provided by a classical ADI in an important way: when the ship > changes attitude, you get an immediate indication of a change in pitch. > However, once a new stable attitude is established the pitch indicator > > moves back to the horizon. Essentially, the device indicates something > more akin to the derivative of pitch than pitch per se. Maybe there > are some circumstances under which this is a good thing, but its not > clear to me what they might be. If you don't have a horizon outside > the ship, you cannot depend the TruTrak ADI to give an absolute pitch > indication. > > Jon > > Jon Goguen > jon.goguen@umassmed.edu > Central Massachusetts > Kitfox Series V Rotax 912S / N456JG (reserved) > Complete except for electrics and avionics > On Sep 28, 2005, at 8:59 PM, Fiveonepw@aol.com wrote: > >> --> AeroElectric-List message posted by: Fiveonepw@aol.com >> >> Did you look at stuff by PCFlightSystems? Maybe they have something >> you can >> use. I use their PDA based EFIS/GPS Nav stuff as my main PFD/NAV >> (VFR) and it >> works quite nicely... >> >> http://pcflightsystems.com/ >> >> Mark Phillips, RV-6A N51PW Columbia TN >> >> > > ________________________________ Message 14 ____________________________________ Time: 01:11:35 PM PST US From: Joseph Larson Subject: Re: AeroElectric-List: Solid State Gyros --> AeroElectric-List message posted by: Joseph Larson Do people actually use the AI for pitch information in any sort of normal flight? Clearly it's used for unusual attitude recovery, but you would notice the unusual attitude because your VSI, airspeed and altimeter are all doing crazy things. But in normal instrument flight, I don't use the AI for pitch information, only for bank information. For pitch, I'm using: 1. Altimeter 2. Airspeed 3. My own pressure on the controls 4. VSI 5. Engine sound and wind noise, which both vary with airspeed, which of course, varies with pitch If I want to institute a climb / descent, I do so by applying pressure to the controls, and I presume that the aircraft will respond appropriately. I control the pitch based on the pressure I apply, and use the altimeter, VSI and airspeed indicator to establish the desired rate of change. Generally speaking in a aircraft trimmed for level flight, a constant pressure on the controls will result in a stabilized climb / descent. At least this is true in the aircraft I've flown, which admittedly is a fairly small variety of types. (Cessnas and a Mooney.) I let the airplane's normal response to short variations in pitch be handled by trim -- a stabile and trimmed airplane will return to level flight after a pitch deviation, and I usually figure that I'm just going to add to my workload if I mess with it myself (except of course, for sudden and extreme variations -- see comments regarding unusual attitude). I'd love to hear if I'm doing something wrong, but I just don't think the AI is very useful for pitch info in normal flight. -Joe do not archive On Sep 29, 2005, at 2:00 PM, Matt Prather wrote: > --> AeroElectric-List message posted by: "Matt Prather" > > > It seems very surprising that the ADI works exactly as you described.. > Instead, I suspect that as long as the airplane is stabilized in a > descent > (negative vertical speed), the display will indicate a nose-down > attitude, > and when stabilized in a climb, it will display a nose-up > attitude. It > looks like the device uses VSI information to cancel slow-term gyro > drift. > > The only weird thing about this behavior is that there probably > isn't a > pitch indication difference between stabilized level flight (vertical > speed=0) whether at Vmo or Vs. > > Say you're are running flat out because ATC told you to keep your > speed > up. The attitude indicator shows level flight. Then they tell you to > enter a hold, you decide to slow down (to save gas), so you pull power > back, and start to roll in nose-up trim to maintain altitude. > Initially, > the ADI correctly indicates this higher pitch attitude. Finally, > you get > down to loiter speed and the nose is actually at a much steeper pitch > attitude than when at Vmo. Once stabilized at the new pitch/speed > combination, the ADI will slowly indicate that the nose is > returning to a > level atttitude.. That's the VSI 'enhanced' feature. I don't > think this > is likely to cause control problems, though it is especially > important to > keep the Airspeed Indicator in your scan. > > I guess there is one other weird behavior.. If you take on a load > of ice, > airspeed will suffer and eventually you won't be able to maintain > altitude, even with the nose pitched up to best L/D (Vy) attitude. > So you > start to descend. I suspect the ADI will indicate a nose down > attitude > even though you are actually pitched up. > > > Regards, > > Matt- > > >> --> AeroElectric-List message posted by: Jon Goguen >> >> >> I looked at the TruTrak ADI at Oshkosh, and came away very concerned >> that it's a potentially dangerous device. If you look at their ads, >> you'l see that they describe the pitch information provided as "gyro >> enhanced vertical speed". As I understood the description of this >> function from the TruTrak reps at Oshkosh, it differs from the pitch >> info provided by a classical ADI in an important way: when the ship >> changes attitude, you get an immediate indication of a change in >> pitch. >> However, once a new stable attitude is established the pitch >> indicator >> >> moves back to the horizon. Essentially, the device indicates >> something >> more akin to the derivative of pitch than pitch per se. Maybe there >> are some circumstances under which this is a good thing, but its not >> clear to me what they might be. If you don't have a horizon outside >> the ship, you cannot depend the TruTrak ADI to give an absolute pitch >> indication. >> >> Jon >> >> Jon Goguen >> jon.goguen@umassmed.edu >> Central Massachusetts >> Kitfox Series V Rotax 912S / N456JG (reserved) >> Complete except for electrics and avionics >> On Sep 28, 2005, at 8:59 PM, Fiveonepw@aol.com wrote: >> >> >>> --> AeroElectric-List message posted by: Fiveonepw@aol.com >>> >>> Did you look at stuff by PCFlightSystems? Maybe they have something >>> you can >>> use. I use their PDA based EFIS/GPS Nav stuff as my main PFD/NAV >>> (VFR) and it >>> works quite nicely... >>> >>> http://pcflightsystems.com/ >>> >>> Mark Phillips, RV-6A N51PW Columbia TN ________________________________ Message 15 ____________________________________ Time: 01:56:59 PM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: ND two-lead alternator question --> AeroElectric-List message posted by: "Robert L. Nuckolls, III" At 05:48 PM 9/29/2005 +0200, you wrote: >--> AeroElectric-List message posted by: Mickey Coggins > > > > Wire it up, run the alternator with solid wire in the > > feeders to IG and L, then put a diode in series with > > each wire one at a time. If insertion of the diode causes > > bus voltage to rise by about 0.6 volts, then that wire > > has been demonstrated to be a sense lead for the purpose > > of providing more accurate control of bus voltage. > >Thanks for the info. I just did this, and I didn't see >any difference with or without the diode. I used a >1N 4004 diode. My battery only voltage was about 12.9v, >and when cranking on the alternator with a 3000rpm >electric hand drill, the voltage went up to about 14.3v >within about 10-15 seconds. I could feel the load on >the drill start out high, then gradually taper off. >I'm measuring the voltage across the battery terminals. > >I agree that a schematic of this alternator's voltage >regulator would be great! > >Thanks again for your help. 3000rpm is at the raggedy edge of minimum speed for regulation at full output so perhaps your experiment was incapable of yielding definitive data. You can rig a 12 or 24 volt transformer to "boost" the line voltage to the drill motor. Was this 3000 a measured value or nameplate value? Bob . . . ________________________________ Message 16 ____________________________________ Time: 03:11:53 PM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: ND two-lead alternator question --> AeroElectric-List message posted by: "Robert L. Nuckolls, III" At 04:25 AM 9/29/2005 -0700, you wrote: >--> AeroElectric-List message posted by: > > >Bob N wrote: Again, like the so called "OV Protection" built into the > regulator > > chip, there are reliability issues with using the same > > chip to annunciate non-operation as well as control an alternator. > > >I agree you should have a separate Lo/Hi voltage indicator but not for the >reasons you state. You also address ND alternator reliability for which >you have no knowledge of and should focus on facts and not your opinion. I focus on nothing but facts George . . . my career success absolutely depends on an artful exploitation of facts. >-The chance of an indication failure and alternator failure (of the kind >that only exist in your dreams Bob) at the same time is unlikely. The lamp >driver and detection is separate from the voltage regulator, even if the >function is contained in the same chip. It is possible that a rare fault >will happen in the first place and even more rare the indicator fails at >the same time. The bulb is more likely to fail, but you can check it every >time you turn your electrical system on before cranking the engine over. >The idiot light will glow just like your car. > >-Second, the so called OV protection is more sophisticated than a so >called crow bar.Also being on-board the alternator is reacts quicker and >more precisely (despite what Bob says). >Bob, you are talking about reliability issues, and you have no idea what >you are talking about. You said you have an engineering degree and >understand failure mode analysis and in particular those of the IC chips >in ND alternators? Where did you go to school and what degree did you get? >I went to LSU for under grad and UW for grad school. You want to do dueling diplomas? Sorry, I can't help you there. I do not have a degree. I bailed from second semester calculus when the TA instructor (who could work problems but couldn't teach) told us that 95% of everything we needed to know about calculus as an engineer was contained in 3 or 4 chapters of a 30 chapter book that took 15 semester hours to slog through. When I checked it out with the head of the math department the next morning, he said, "Son, the engineering department says you need an education in math. I teach math. Yeah, it's for math majors but I DO teach math. Take it or leave it." I was a few hours short of being a junior, working full time, raising two kids, had yet to take a real engineering course and was learning more on my job than I was in school. That was my last class at Wichita State University. They could not provide me with what I needed. My first consulting job was 1968 for Mobilizer where I designed the electrics for a hospital patient transporter that was being designed here in Wichita. See: http://www.aeroelectric.com/Pictures/Mobilizer_3s.jpg The old guy on the prototype is my Dad who I was able to remove and replace on the adjacent table without laying a hand on him. The electrics for the machine were no big deal but I did my first analog computer and data acquisition system for measuring and comparing the relative efficiencies of different belts and drive trains. This was a few months after I bailed from WSU. My lead on this program was Ken Razak, a former dean who built WSU's engineering department and left to do more interesting things. He seemed reasonably happy with my performance. He paid my invoices. I think I was hitting him for about $10/hour back then). I'm still doing work for him from time to time . . . for a whole lot more than $10/hour! He's 87 years old and still looking for interesting things to do. You can beat on me all you wish with your diplomas. I've got thousands of happy customers and dozens of happy supervisors who would stand behind me. Your diplomas are going to be a bit ragged by the time your through whacking on all of us. >What reliability data do you have? I will admit my info is anadotical, but >it is backed up by conversations with Nippon Denso engineers, auto >industry electrical service experts and the National Transportation Safety >data base that tracks reliability of all aspects of automobiles, including >electrical charging systems (alternators). Since there a millions ND >alternators in service with no record of recalls, consumer complaint or >safety related issues, such as fires, I would say that is pretty good >statistics, not to mention the millions of ND alternators in industrial >equipment, going 24/7 for year after year with no problem. What >reliability info do you have? I know everyone gives Paul crap about not >showing data, lets see your ND alternator reliability data, please. >(facts: model, place, failure mode, indications and affect of failure) George, this is the FAA no Bob talking about reliability issues. If the FAA were looking over my shoulder for certifying an IR alternator onto a type certificated airplane, they would ask me how I propose to provide OV protection. OV "protection" on the same chip with voltage control would never fly with the FAA and there are good reasons for that design goal even if you don't personally endorse them. Please forward list of all the folks who worship at the altar of anecdotal data, perhaps I can submit this as part of my certification basis? Please stop whacking at me or anyone else for pursuing design goals that are different from yours. Please wire your airplane as you see fit and based on any information you consider relevant to your decision. Understand that what I offer is advice based not on my opinions but on facts and philosophies I have brought with me working under the wings of Learjet (Electrical group lead engineer on GP-180), Beech/Raytheon (Sr. Electronics engineer 15+ years and now lead subject matter expert), Electromech Technologies (only electron herder on staff for 5 years and lead for 4 more) and 38+ years of delivering design services to a clientele of what I presume are happy customers . . . they keep coming back for more of what I have to offer. Bob . . . Summa cum gunk. HNTGYHDE (Hammer'n tongs, get yer hands dirty engineer) . . . who would rather make things work than sit in a classroom hypothesizing about them. ________________________________ Message 17 ____________________________________ Time: 04:02:26 PM PST US From: Jon Goguen Subject: Re: AeroElectric-List: Solid State Gyros --> AeroElectric-List message posted by: Jon Goguen I overstated the case slightly in my initial comment. Matt is probably correct in thinking that the TruTrak ADI will give a give a nose up or nose down indication when the plane is climbing or descending, but not when stabilized in level flight regardless of attitude. In this respect, it behaves like a VSI. Nonetheless, it doesn't give true attitude information, and could indicate negative pitch during a decent with the nose high, or zero pitch when hanging from the prop, etc. The reason I think this instrument could be dangerous is because it may require one to do some extra thinking in unusual situations on the edge of real trouble. I've been trained to depend on the as ADI as the primary instrument for recovery from unusual attitudes. With the TruTrak instrument, I wouldn't be sure what the display indication meant without reference to other instruments, which would slow my response. True pitch information is valuable. I have a VSI and altimeter to tell me if I'm climbing or descending. I don't think corrupting the pitch information provided on the ADI with input determined by vertical speed is a good idea. I'm sure it's not a problem during normal VFR and might even be convenient, but you don't really need an ADI then anyway. I think the difficulty that TruTrak has in describing the behavior of their device is an indication of the confusion it could cause. How does it behave if the static port ices over? Seems that I would have no interpretable pitch information, just at the time I've lost my altimeter, VSI, and airspeed indicator. I could keep the wings level, but would have to depend on the sound of the wind for pitch. I experienced loss of both pitot and static ports to light icing in a Cherokee with no pitot heat. Pitch information seemed useful at the time. The TruTrak ADI is probably a fine instrument. It just needs a placard reading "No Reliable Pitch Information". Jon Jon Goguen jon.goguen@umassmed.edu Central Massachusetts Kitfox Series V Rotax 912S / N456JG (reserved) Complete except for electrics and avionics On Sep 29, 2005, at 4:10 PM, Joseph Larson wrote: > --> AeroElectric-List message posted by: Joseph Larson > > > Do people actually use the AI for pitch information in any sort of > normal flight? Clearly it's used for unusual attitude recovery, but > you would notice the unusual attitude because your VSI, airspeed and > altimeter are all doing crazy things. > > But in normal instrument flight, I don't use the AI for pitch > information, only for bank information. For pitch, I'm using: > > 1. Altimeter > 2. Airspeed > 3. My own pressure on the controls > 4. VSI > 5. Engine sound and wind noise, which both vary with airspeed, which > of course, varies with pitch > > If I want to institute a climb / descent, I do so by applying > pressure to the controls, and I presume that the aircraft will > respond appropriately. I control the pitch based on the pressure I > apply, and use the altimeter, VSI and airspeed indicator to establish > the desired rate of change. Generally speaking in a aircraft trimmed > for level flight, a constant pressure on the controls will result in > a stabilized climb / descent. At least this is true in the aircraft > I've flown, which admittedly is a fairly small variety of types. > (Cessnas and a Mooney.) > > I let the airplane's normal response to short variations in pitch be > handled by trim -- a stabile and trimmed airplane will return to > level flight after a pitch deviation, and I usually figure that I'm > just going to add to my workload if I mess with it myself (except of > course, for sudden and extreme variations -- see comments regarding > unusual attitude). > > I'd love to hear if I'm doing something wrong, but I just don't think > the AI is very useful for pitch info in normal flight. > > -Joe > > do not archive > > On Sep 29, 2005, at 2:00 PM, Matt Prather wrote: > >> --> AeroElectric-List message posted by: "Matt Prather" >> >> >> It seems very surprising that the ADI works exactly as you described.. >> Instead, I suspect that as long as the airplane is stabilized in a >> descent >> (negative vertical speed), the display will indicate a nose-down >> attitude, >> and when stabilized in a climb, it will display a nose-up >> attitude. It >> looks like the device uses VSI information to cancel slow-term gyro >> drift. >> >> The only weird thing about this behavior is that there probably >> isn't a >> pitch indication difference between stabilized level flight (vertical >> speed=0) whether at Vmo or Vs. >> >> Say you're are running flat out because ATC told you to keep your >> speed >> up. The attitude indicator shows level flight. Then they tell you to >> enter a hold, you decide to slow down (to save gas), so you pull power >> back, and start to roll in nose-up trim to maintain altitude. >> Initially, >> the ADI correctly indicates this higher pitch attitude. Finally, >> you get >> down to loiter speed and the nose is actually at a much steeper pitch >> attitude than when at Vmo. Once stabilized at the new pitch/speed >> combination, the ADI will slowly indicate that the nose is >> returning to a >> level atttitude.. That's the VSI 'enhanced' feature. I don't >> think this >> is likely to cause control problems, though it is especially >> important to >> keep the Airspeed Indicator in your scan. >> >> I guess there is one other weird behavior.. If you take on a load >> of ice, >> airspeed will suffer and eventually you won't be able to maintain >> altitude, even with the nose pitched up to best L/D (Vy) attitude. >> So you >> start to descend. I suspect the ADI will indicate a nose down >> attitude >> even though you are actually pitched up. >> >> >> Regards, >> >> Matt- >> >> >>> --> AeroElectric-List message posted by: Jon Goguen >>> >>> >>> I looked at the TruTrak ADI at Oshkosh, and came away very concerned >>> that it's a potentially dangerous device. If you look at their ads, >>> you'l see that they describe the pitch information provided as "gyro >>> enhanced vertical speed". As I understood the description of this >>> function from the TruTrak reps at Oshkosh, it differs from the pitch >>> info provided by a classical ADI in an important way: when the ship >>> changes attitude, you get an immediate indication of a change in >>> pitch. >>> However, once a new stable attitude is established the pitch >>> indicator >>> >>> moves back to the horizon. Essentially, the device indicates >>> something >>> more akin to the derivative of pitch than pitch per se. Maybe there >>> are some circumstances under which this is a good thing, but its not >>> clear to me what they might be. If you don't have a horizon outside >>> the ship, you cannot depend the TruTrak ADI to give an absolute pitch >>> indication. >>> >>> Jon >>> >>> Jon Goguen >>> jon.goguen@umassmed.edu >>> Central Massachusetts >>> Kitfox Series V Rotax 912S / N456JG (reserved) >>> Complete except for electrics and avionics >>> On Sep 28, 2005, at 8:59 PM, Fiveonepw@aol.com wrote: >>> >>> >>>> --> AeroElectric-List message posted by: Fiveonepw@aol.com >>>> >>>> Did you look at stuff by PCFlightSystems? Maybe they have something >>>> you can >>>> use. I use their PDA based EFIS/GPS Nav stuff as my main PFD/NAV >>>> (VFR) and it >>>> works quite nicely... >>>> >>>> http://pcflightsystems.com/ >>>> >>>> Mark Phillips, RV-6A N51PW Columbia TN > > ________________________________ Message 18 ____________________________________ Time: 04:09:57 PM PST US From: "Carl Morgan" Subject: AeroElectric-List: VANs ND Alternator wiring --> AeroElectric-List message posted by: "Carl Morgan" Hi all, I've been following the list for a few years and watched IR/OR/OV debates with "interest". Given the following assumption: We have a VANs ND IR 60 Amp alternator (w/ internal OV protection) (3 wire + ground). It is acceptable to us and we want an idiot light directly from the alternator and no external OV sensing. We want the light to come on with the main bus power, off during engine running / battery charging. An emergency alternator 'off' control and remote voltage sensing from the battery would be good if possible. Can someone suggest a possible wiring solution that utilises the functionality of the ND alternator (based on the LAMP/RED, IG/GREEN, S/BLUE - http://www.aeroelectric.com/Reference_Docs/Alternator_Data/ND_3-wire.jpg ). Currently I seem to have VANs not using the full functionality and Bob on principle not happy with recommending a non OV / IR solution. Anybody care to offer a solution? Thanks, Carl PS: This is part of a dual ALT, dual Battery (Z-14) configuration - the second alt will be external OR, OV based. Both busses will have active Voltage / Amp monitoring. -- ZK-VII - RV 7A QB - wiring Cromwell, New Zealand -- ________________________________ Message 19 ____________________________________ Time: 06:51:29 PM PST US From: "Frank Stringham" Subject: Re: AeroElectric-List: ND two-lead alternator question --> AeroElectric-List message posted by: "Frank Stringham" Degrees degrees.............I have a few ( AS, BS, MBA) and I will give sway to the man with facts, OJT, and tons of experience anytime. Now lets see.................Bill Gates ......zero degrees, great idea, mucho grande $$$$$$$$$$$$$$. We all know what BS stands for (Bull S***), and an MS is just More of the Same, and PhD are just Piled Higher and Deeper. So back to Bob's aeroelectric and still learning the wonderful world of electronics, aircraft wiring, and panel installation. Experiment all you want, even debate with your FACTS so we may decide for ourselves what might work for us, but leave the degree home please.......... Frank @ SGU and SLC >From: "Robert L. Nuckolls, III" >Reply-To: aeroelectric-list@matronics.com >To: aeroelectric-list@matronics.com >Subject: Re: AeroElectric-List: ND two-lead alternator question >Date: Thu, 29 Sep 2005 17:09:05 -0500 > >--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" > > >At 04:25 AM 9/29/2005 -0700, you wrote: > > >--> AeroElectric-List message posted by: > > > > >Bob N wrote: Again, like the so called "OV Protection" built into the > > regulator > > > chip, there are reliability issues with using the same > > > chip to annunciate non-operation as well as control an alternator. > > > > > >I agree you should have a separate Lo/Hi voltage indicator but not for >the > >reasons you state. You also address ND alternator reliability for which > >you have no knowledge of and should focus on facts and not your opinion. > > I focus on nothing but facts George . . . my career > success absolutely depends on an artful exploitation > of facts. > > > >-The chance of an indication failure and alternator failure (of the kind > >that only exist in your dreams Bob) at the same time is unlikely. The >lamp > >driver and detection is separate from the voltage regulator, even if the > >function is contained in the same chip. It is possible that a rare fault > >will happen in the first place and even more rare the indicator fails at > >the same time. The bulb is more likely to fail, but you can check it >every > >time you turn your electrical system on before cranking the engine over. > >The idiot light will glow just like your car. > > > >-Second, the so called OV protection is more sophisticated than a so > >called crow bar.Also being on-board the alternator is reacts quicker and > >more precisely (despite what Bob says). > > > > > > >Bob, you are talking about reliability issues, and you have no idea what > >you are talking about. You said you have an engineering degree and > >understand failure mode analysis and in particular those of the IC chips > >in ND alternators? Where did you go to school and what degree did you >get? > >I went to LSU for under grad and UW for grad school. > > You want to do dueling diplomas? Sorry, I can't help > you there. I do not have a degree. I bailed from second > semester calculus when the TA instructor (who could work > problems but couldn't teach) told us that 95% of everything > we needed to know about calculus as an engineer was contained > in 3 or 4 chapters of a 30 chapter book that took 15 semester > hours to slog through. When I checked it out with the head of > the math department the next morning, he said, "Son, the engineering > department says you need an education in math. I teach math. Yeah, > it's for math majors but I DO teach math. Take it or leave it." > > I was a few hours short of being a junior, working full time, > raising two kids, had yet to take a real engineering course > and was learning more on my job than I was in school. That > was my last class at Wichita State University. They could > not provide me with what I needed. > > My first consulting job was 1968 for Mobilizer > where I designed the electrics for a hospital patient > transporter that was being designed here in Wichita. > See: > >http://www.aeroelectric.com/Pictures/Mobilizer_3s.jpg > > The old guy on the prototype is my Dad who I was able to > remove and replace on the adjacent table without > laying a hand on him. The electrics for the machine > were no big deal but I did my first analog computer > and data acquisition system for measuring and > comparing the relative efficiencies of different > belts and drive trains. This was a few months after > I bailed from WSU. My lead on this program was > Ken Razak, a former dean who built WSU's engineering > department and left to do more interesting things. > He seemed reasonably happy with my performance. He > paid my invoices. I think I was hitting him for > about $10/hour back then). I'm still doing work for > him from time to time . . . for a whole lot more > than $10/hour! He's 87 years old and still looking > for interesting things to do. > > You can beat on me all you wish with your diplomas. > I've got thousands of happy customers and dozens of > happy supervisors who would stand behind me. Your > diplomas are going to be a bit ragged by the time > your through whacking on all of us. > > >What reliability data do you have? I will admit my info is anadotical, >but > >it is backed up by conversations with Nippon Denso engineers, auto > >industry electrical service experts and the National Transportation >Safety > >data base that tracks reliability of all aspects of automobiles, >including > >electrical charging systems (alternators). Since there a millions ND > >alternators in service with no record of recalls, consumer complaint or > >safety related issues, such as fires, I would say that is pretty good > >statistics, not to mention the millions of ND alternators in industrial > >equipment, going 24/7 for year after year with no problem. What > >reliability info do you have? I know everyone gives Paul crap about not > >showing data, lets see your ND alternator reliability data, please. > >(facts: model, place, failure mode, indications and affect of failure) > > George, this is the FAA no Bob talking about reliability > issues. If the FAA were looking over my shoulder for certifying an > IR alternator onto a type certificated airplane, they > would ask me how I propose to provide OV protection. OV > "protection" on the same chip with voltage control > would never fly with the FAA and there are good reasons > for that design goal even if you don't personally endorse > them. Please forward list of all the folks who worship at > the altar of anecdotal data, perhaps I can submit this as > part of my certification basis? > > Please stop whacking at me or anyone else for pursuing > design goals that are different from yours. Please wire > your airplane as you see fit and based on any information > you consider relevant to your decision. Understand that > what I offer is advice based not on my opinions but on > facts and philosophies I have brought with me working > under the wings of Learjet (Electrical group lead > engineer on GP-180), Beech/Raytheon (Sr. Electronics > engineer 15+ years and now lead subject matter expert), > Electromech Technologies (only electron herder on staff > for 5 years and lead for 4 more) and 38+ years of > delivering design services to a clientele of what > I presume are happy customers . . . they keep coming > back for more of what I have to offer. > > Bob . . . Summa cum gunk. HNTGYHDE > > (Hammer'n tongs, get yer hands dirty engineer) > > . . . who would rather make things work than sit in > a classroom hypothesizing about them. > > ________________________________ Message 20 ____________________________________ Time: 07:26:59 PM PST US From: "Rodney Dunham" Subject: AeroElectric-List: OVP failure consequent to VR failure 7.50 BARRACUDA_HEADER_FP56 RBL: Blacklist bl.spamcop [Blocked - see ] --> AeroElectric-List message posted by: "Rodney Dunham" George, I was reviewing a back issue of Aviation Safety magazine while doing my business the other morning (yes, I keep them in a rack next to the john, thank you very much) and noticed an article on the service bulletin (SEB03-3A) warning of OV protection failure consequent to VR failure in the VR600A manufactured by Electrosystems, Inc. This SB affects the 100 and 200 series Cessna aircraft. It seems the VR600A's installation instructions called for removal of the OEM (Cessna) installed over-voltage protection device. The VR600A has an internal OVP module which was believed by the relevent engineers to be good enough. Not so, it would appear. The AD calls for replacement of the PMA'd VRs and reinstallation of the OEM overvoltage protection modules due to just such failures as you consider only a lofty imagination of our fearless leader! Hey, let's keep the dialog civil. There's room here for diagreement without diatribe. Rodney in Tennessee BS, MD, PPL / SKR, C172, C182, Sonex ________________________________ Message 21 ____________________________________ Time: 07:27:23 PM PST US From: "Rodney Dunham" Subject: AeroElectric-List: OVP failure consequent to VR failure 7.50 BARRACUDA_HEADER_FP56 RBL: Blacklist bl.spamcop [Blocked - see ] --> AeroElectric-List message posted by: "Rodney Dunham" George, I was reviewing a back issue of Aviation Safety magazine while doing my business the other morning (yes, I keep them in a rack next to the crapper, thank you very much) and noticed an AD on alternators affecting multiple single engine rides including almost all the Cessna line and some Beach products as well. The AD was warning of OV protection failure consequent to VR failure in the VR600 series VRs. It seems the PMA'd VRs installation instructions called for removal of the OEM (Cessna) installed over-voltage protection device. The PMA'd VRs had internal OVP modules which were believed by the relevent engineers to be good enough. Not so. The AD calls for removal of the PMA'd VRs and reinstallation of the OEM overvoltage protection modules due to just such failures as you consider only a lofty imagination our fearless leader! Hey, let's keep the dialog civil. There's room here for diagreement without diatribe. Rodney in Tennessee BS, MD, PPL / SKR, C172, C182, Sonex ________________________________ Message 22 ____________________________________ Time: 07:41:35 PM PST US From: N1deltawhiskey@aol.com Subject: Re: AeroElectric-List: ND two-lead alternator question --> AeroElectric-List message posted by: N1deltawhiskey@aol.com Bob, Good posting. I too have gotten a little tired of those who would flaunt their college degrees and awards of achievement as an indication that I should somehow listen to them because they know more than I do, or that someone else who does not have such a degree. My degree in electrical engineering taught me that there were many knowledgeable people who were thought they knew a lot, but could not teach it. Of course, they acquired their jobs based on resumes, association with certain institutions and the like, not on their ability to teach something. I sometimes thought of Paul being one of those types, and one could probably put George there too. It is also my perception that someone's ability to explain something logically and intelligently is an indication of their actual understanding of the subject. Degrees and awards, for some people, do little more than feed their egos. What a waste. I think what was the most beneficial for me is that I learned a little better how to think, not what to think. I have never put myself forward as an expert in much of anything, but I am not dumb either. I did not even bother to go after my P.E. stamp, and if I had, I doubt I would use it. Of course, I would surrender my degree and whatever I gained by spending the time and effort to get it to be as economically productive as one of my neighbors (well, within single digit miles, anyway). He happens to currently be the wealthiest man in the WORLD! And guess what - he never finished college either. I wonder if there is an economics professor out there somewhere with an ego big enough to suggest he could tell Mr. Gates how to accumulate wealth. Guess as to whom I would listen to garner information on how to create wealth. Anyway, keep on truckin'. An thanks for all the great insights shared over the years I have been on this list. Regards, Doug Windhorn In a message dated 29-Sep-05 15:13:48 Pacific Standard Time, nuckollsr@cox.net writes: --> AeroElectric-List message posted by: "Robert L. Nuckolls, III" At 04:25 AM 9/29/2005 -0700, you wrote: >--> AeroElectric-List message posted by: > > >Bob N wrote: Again, like the so called "OV Protection" built into the > regulator > > chip, there are reliability issues with using the same > > chip to annunciate non-operation as well as control an alternator. > > >I agree you should have a separate Lo/Hi voltage indicator but not for the >reasons you state. You also address ND alternator reliability for which >you have no knowledge of and should focus on facts and not your opinion. I focus on nothing but facts George . . . my career success absolutely depends on an artful exploitation of facts. >-The chance of an indication failure and alternator failure (of the kind >that only exist in your dreams Bob) at the same time is unlikely. The lamp >driver and detection is separate from the voltage regulator, even if the >function is contained in the same chip. It is possible that a rare fault >will happen in the first place and even more rare the indicator fails at >the same time. The bulb is more likely to fail, but you can check it every >time you turn your electrical system on before cranking the engine over. >The idiot light will glow just like your car. > >-Second, the so called OV protection is more sophisticated than a so >called crow bar.Also being on-board the alternator is reacts quicker and >more precisely (despite what Bob says). >Bob, you are talking about reliability issues, and you have no idea what >you are talking about. You said you have an engineering degree and >understand failure mode analysis and in particular those of the IC chips >in ND alternators? Where did you go to school and what degree did you get? >I went to LSU for under grad and UW for grad school. You want to do dueling diplomas? Sorry, I can't help you there. I do not have a degree. I bailed from second semester calculus when the TA instructor (who could work problems but couldn't teach) told us that 95% of everything we needed to know about calculus as an engineer was contained in 3 or 4 chapters of a 30 chapter book that took 15 semester hours to slog through. When I checked it out with the head of the math department the next morning, he said, "Son, the engineering department says you need an education in math. I teach math. Yeah, it's for math majors but I DO teach math. Take it or leave it." I was a few hours short of being a junior, working full time, raising two kids, had yet to take a real engineering course and was learning more on my job than I was in school. That was my last class at Wichita State University. They could not provide me with what I needed. My first consulting job was 1968 for Mobilizer where I designed the electrics for a hospital patient transporter that was being designed here in Wichita. See: http://www.aeroelectric.com/Pictures/Mobilizer_3s.jpg The old guy on the prototype is my Dad who I was able to remove and replace on the adjacent table without laying a hand on him. The electrics for the machine were no big deal but I did my first analog computer and data acquisition system for measuring and comparing the relative efficiencies of different belts and drive trains. This was a few months after I bailed from WSU. My lead on this program was Ken Razak, a former dean who built WSU's engineering department and left to do more interesting things. He seemed reasonably happy with my performance. He paid my invoices. I think I was hitting him for about $10/hour back then). I'm still doing work for him from time to time . . . for a whole lot more than $10/hour! He's 87 years old and still looking for interesting things to do. You can beat on me all you wish with your diplomas. I've got thousands of happy customers and dozens of happy supervisors who would stand behind me. Your diplomas are going to be a bit ragged by the time your through whacking on all of us. >What reliability data do you have? I will admit my info is anadotical, but >it is backed up by conversations with Nippon Denso engineers, auto >industry electrical service experts and the National Transportation Safety >data base that tracks reliability of all aspects of automobiles, including >electrical charging systems (alternators). Since there a millions ND >alternators in service with no record of recalls, consumer complaint or >safety related issues, such as fires, I would say that is pretty good >statistics, not to mention the millions of ND alternators in industrial >equipment, going 24/7 for year after year with no problem. What >reliability info do you have? I know everyone gives Paul crap about not >showing data, lets see your ND alternator reliability data, please. >(facts: model, place, failure mode, indications and affect of failure) George, this is the FAA no Bob talking about reliability issues. If the FAA were looking over my shoulder for certifying an IR alternator onto a type certificated airplane, they would ask me how I propose to provide OV protection. OV "protection" on the same chip with voltage control would never fly with the FAA and there are good reasons for that design goal even if you don't personally endorse them. Please forward list of all the folks who worship at the altar of anecdotal data, perhaps I can submit this as part of my certification basis? Please stop whacking at me or anyone else for pursuing design goals that are different from yours. Please wire your airplane as you see fit and based on any information you consider relevant to your decision. Understand that what I offer is advice based not on my opinions but on facts and philosophies I have brought with me working under the wings of Learjet (Electrical group lead engineer on GP-180), Beech/Raytheon (Sr. Electronics engineer 15+ years and now lead subject matter expert), Electromech Technologies (only electron herder on staff for 5 years and lead for 4 more) and 38+ years of delivering design services to a clientele of what I presume are happy customers . . . they keep coming back for more of what I have to offer. Bob . . . Summa cum gunk. HNTGYHDE (Hammer'n tongs, get yer hands dirty engineer) . . . who would rather make things work than sit in a classroom hypothesizing about them. ________________________________ Message 23 ____________________________________ Time: 08:51:23 PM PST US From: GMC Subject: Re: AeroElectric-List: Solid State Gyros --> AeroElectric-List message posted by: GMC Hi Jon, I don't have my Trutrak yet because I am waiting for the autopilot version. Initially I had some of the same reservations you are expressing. If you want factual data call the company and they will answer your concerns and questions. One thing that you may not be aware of is the Trutrak ADI has a low airspeed warning for that nose high descent you (and I) are worried about. My understanding is that the little solid state gyros have a high drift rate so they must be stabilized in roll by internal magnetometer or GPS and in pitch by vertical speed. (-disclaimer I have not seen or flown the Trutrak ADI.) Analyze what you actually need to know when instrument flying, attitude or flight path, in most cases we use the attitude indicator to establish flight path that must be verified on other instruments. The Trutrak shows flight path plus V/S and low airspeed indications. Zero pitch on the ADI will be level flight at any speed, zero pitch on the attitude indicator will be level flight at only one airspeed. Jon Goguen wrote: >--> AeroElectric-List message posted by: Jon Goguen > >Nonetheless, it doesn't give true attitude information, and could indicate negative pitch during a decent >with the nose high, or zero pitch when hanging from the prop, etc. > Your A/H would also be giving information that would require interpretation and verification by reference to other instruments, my understanding is yes the ADI would show descent plus an airspeed warning, and.highly unlikely that you would be hanging from the prop but if you did what would your horizon show, maybe wild gyrations? > reason I think this instrument could be dangerous is because it may >require one to do some extra thinking in unusual situations on the edge >of real trouble. > The ADI has been reported to be easier to fly than a standard horizon and presents more information on one instrument than the horizon so there should be less chance of getting into trouble. > >How does it behave if the static port ices >over? Seems that I would have no interpretable pitch information, > Good question, not sure what the gyros would show without a stabilizing static input or if the old "break the glass face" will work, I would presume that an iced up pitot would cause erroneous or no low speed warning. In any case IFR aircraft normally have alternate static, (another plus for Van's static ports versus a Piper pitot/static setup, I cannot imagine them icing up in a RV aircraft mounted on the aft narrowing fuselage). Take care, George in Langley B.C. ________________________________ Message 24 ____________________________________ Time: 10:18:00 PM PST US From: Mickey Coggins Subject: Re: AeroElectric-List: ND two-lead alternator question --> AeroElectric-List message posted by: Mickey Coggins > 3000rpm is at the raggedy edge of minimum speed for > regulation at full output so perhaps your experiment > was incapable of yielding definitive data. You can > rig a 12 or 24 volt transformer to "boost" the line > voltage to the drill motor. Was this 3000 a measured > value or nameplate value? Nameplate value. I'll see if I can find a way to spin it faster. I need a new drill anyway. Thanks! -- Mickey Coggins http://www.rv8.ch/ #82007 finishing do not archive