Well said Chris, and I definitely love your spirit of taking risk for something we love in life! I am a risk taker myself as well, believe me! Sorry that my posts did sound a bit too "negative" to you, but I didn't really intend to say anything "negative", as I was partly making a joke with Luis and partly trying to explore some "secret" on how folks can build reliable and safe KR2 at affordable costs...!
Yes, I had to confess that several tragic events have happened to people so close to me in the past 8 month or so, and my perception on safety of some of the "experimental" aircraft has been impacted negatively indeed. So, I guess this has affected my posts in a different tone somehow in the deepest bottom of my subconscious, unfortunately.... best of luck! Dr. Hsu On Thu, Jul 7, 2022, 11:36 PM Chris Pryce <[email protected]> wrote: > I hate to be that guy but I have to ask the question after seeing multiple > negative posts: Do you have a flying KR or even a flying airplane at all? > All I've seen the past couple of days is negative commentary. > > I've flown 200 hours in a little over two years with Lowes lawn and garden > parts, no magnetos and no issues. We are here to experiment with our > experimentals. There is always risk. If you don't accept any risk you will > never fly. We all make the decision of what is our personal level of risk > and operate accordingly. Can I crash and die? Yes. Could I die driving on > my way to work? Yes. Personally, I'd rather go in a blaze of glory doing > something I love. > > Keep on building, love the process, and enjoy the fruits of your labor. > > Chris Pryce > Vacaville, CA > > > On Thu, Jul 7, 2022, 21:12 Dr. Feng Hsu via KRnet <[email protected]> > wrote: > >> hey Victor & Luis, >> >> That's what would happen to us if redundant systems are made of the same >> component with identical design! In highly sophisticated engineering >> system, one should never say "that's impossible or unlikely to happen". I >> understand all the pros for the Electronic ignition system that Luis >> listed, however I would not feel confident if the two redundant Electronic >> ignition modules are identical component. Yes, two independent power supply >> with separate batteries do contribute on risk reduction, but that might be >> not good enough to offset the "CCF" (common cause or common mode failures) >> contribution to risk of losing the system during flight.... >> >> Do you have some test or reliability data on the SDS CP1 module from the >> vendor? I will feel better if the failure rate is in the range below 1E-4?! >> >> Best of luck! >> >> Dr. Hsu >> >> >> On Thu, Jul 7, 2022, 8:08 PM victor taylor via KRnet < >> [email protected]> wrote: >> >>> Hey Luis, >>> >>> At Velocity we still keep one magneto on all our aircraft. I had dinner >>> with a Velocity owner who had dual batteries, dual alternators and dual >>> electronic ignition. I suggested that he have one magneto and he said >>> absolutely not and went on to say that there was no way both systems could >>> fail at once. Four months later he and his wife were coming out of >>> Kissimmee Florida and both systems failed within a minute of each other. It >>> totaled the aircraft and put them both in the hospital for over three >>> months each. He is now building another Velocity that will have one mag and >>> one electronic ignition. >>> Your system is unlikely to fail but it’s not impossible. Magnetos are >>> definitely old technology and way less efficient. But time has proven that >>> dual mags are highly reliable. >>> At the end of the day we are flying home made wooden aircraft with >>> automotive based engines on many of them. It’s relatively safe but not >>> quiet as safe as a certified aircraft with that 60 year old technology. How >>> much “experimental” we want to fly our families in is what it all boils >>> down to. >>> >>> Victor Taylor CFII >>> >>> >>> On Jul 7, 2022, at 19:09, Tony King via KRnet <[email protected]> >>> wrote: >>> >>> >>> In addition to all the points Luis has made, pretty much every car on >>> the road today has electronic ignition, with far less redundancy than Luis >>> has outlined, yet ignition failures are quite rare given the number of >>> units in operation. Whilst there may be more complexity, the reliability >>> of electronic systems is in a whole different ball park to mechanical >>> systems. Of course the failure modes are different too, and regardless of >>> which system(s) one chooses it's essential to understand and address how >>> they might let you down. >>> >>> TK >>> >>> On Fri, 8 Jul 2022 at 09:21, Luis Claudio via KRnet < >>> [email protected]> wrote: >>> >>>> Dr. HSU, oh ye of little faith... I do suggest you look into the "SDS >>>> CP1 electronic ignition systems". It means that I have dual >>>> independent power sources for controlling each independent timing computer >>>> with >>>> automatic customization for RPM and load (manifold pressure). The computer >>>> monitors my manifold pressure and smooths out the engine timing to give you >>>> the best engine performance on your climb or cruise. You are always one set >>>> of points or capacitor failure before your engine goes to hades... (you >>>> know "Hell")... >>>> >>>> Consider this" >>>> 1. The engine timing with an electronic ignition system does not drift >>>> from the setpoint since there is no mechanical wear and tear >>>> 2. Each independent computer controls an independent bank of spark >>>> plugs (4 upper and 4 lower) >>>> 3. You can customize the power curve so as you climb, the computer >>>> compensates by adjusting your engine's timing for the best performance. >>>> 4. Two completely independent batteries, one acting as primary, and the >>>> other as backup. >>>> 5. No mandatory 500 hr overhaul >>>> 6. No moving parts in the whole system... none >>>> 7. Each computer is capable of advancing or retarding the timing of >>>> your engine for best economy or to prevent detonation based on manifold >>>> pressure. >>>> 8. Lean of peak adjustments extracts all possible energy from the fuel, >>>> picking up a few extra knots which are lost running leaner mixtures. >>>> 9. Low current draw, long spark duration, 4 cylinder coil pack and >>>> controller draw about 1.2 amps at 2500 RPM. >>>> >>>> and there you have it... >>>> >>>> Luis >>>> >>>> >>>> -- >>> KRnet mailing list >>> [email protected] >>> https://list.krnet.org/mailman/listinfo/krnet >>> >>> -- >>> KRnet mailing list >>> [email protected] >>> https://list.krnet.org/mailman/listinfo/krnet >>> >> -- >> KRnet mailing list >> [email protected] >> https://list.krnet.org/mailman/listinfo/krnet >> >
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