Dual electronic ignition
I am building a glasair 3. It will have a lycoming io540k1a5. I want to install a lightspeed ignition in it. My question is whether I should install two? I have always been conservative with my aircraft and the glasair 3 wing loading is reason enough to continue this policy. However, maybe the technology has come along enough that it would statistically be just as unlikely or even less likely to have two electronic systems fail as apposed to a mag and an electronic system failure. I can predict some of the debate but I am interested to hear the differing opinions in the hopes that there will be things I haven't thought of yet. I haven't made up my mind yet and I would like the benefits of dual electronic ignition for the efficiency and relative simplicity. I am considering litespeed.
when i bought my electroair ignition, Jeff Rose the "inventor" was the proprietor. i asked about installing dual system or keeping one mag. he politely refused to give me advice about what i should do, but told me he flew with one mag. that was good enough for me. i do, too. investigate "emag" too.
I recently went through a month long debacle trying to troubleshoot and fix a generation old electronic ignition (brand intentionally omitted). The final diagnosis was that the computer board had failed, which is basically irreparable at this point due to parts availability or lack thereof. This was the unit's 3rd failure in 800 hours - two were in-flight failures of a Hall effect sensor and now this board failure. I have no idea how this translates to the newer version of the ignition or to other brands. Still, 3 failures in 800 hours is a bad record, IMO.
I replaced the unit with Pmag, mostly because of ease of installation and the fact that I still want the performance advantages of an electronic ignition. There are plenty of reports of Pmag failures for various reasons (failed magnets, heat, etc.)
I have about 1500 hours behind magnetos. 2 mags x 350 hours + a single mag (and EI) x 800 hours. One mag failure over that period.
So my data is very limited, but indicates that electronic ignitions are much less reliable than magnetos. Comments on builder forums seem to agree with this sentiment, regardless of which EI we're talking about.
Which is why I keep one mag to serve as the stone simple, relatively reliable backup to my EI.
One advantage to using magnetos is that if you're on the road and one fails, lots of A&P's and IA's have the parts and expertise to help you get back in the air. With EI's you're not likely to find much help if you drop into a small airport out in the boonies with a bum ignition.
I have installed more than a couple of electronic ignitions over the last several years and the thing I have noticed is that they are improving things constantly. To me this sort of translates into "still have room for improvement". The only ignition failure we have had in the last 5 years was an electronic. The term "relative simplicity" that you use tells me you haven't really looked at the entire system. There is a fair amount of wiring involved with the dual electronic ignition and much of it is 20ga. or smaller. For me there is too much opportunity for failure due to an installation short coming on the part of the installer. If properly done, it works well. I just finished a dual Lightspeed on a customers Lancair and the new style crank sensor mounts are much better than the earlier ones.
Personally, for me the jury is still out. I have a pair of mags.
Last edited by Neil; 07-18-2012 at 08:26 PM.
It sounds like Kyle's advice is well worthwhile.
Personally I don't see the attraction of changing to electronic ignition. In a Glassair it is going to be powerful and high performance with a stock 540,and I think that engine has a good reputation.
Maybe the ei will give you 15 more hp, maybe or maybe not. And how much does the ei cost compared to the mags? And I assume if you bought the engine it already came with mags.
Mags are kind of boring, they just sit there hour after hour, year after year and keep on making sparks.
It sort of sounds like a case of fiddleitus or can't leave well enough alone. But that is common in EAA, and part of what makes hope for something new springs eternal.
And I think you are pretty smart to ask for info from others. A lot of folks make up their mind and don't want to hear anything that doesn't agree with their opinion.
Last edited by Bill Greenwood; 07-18-2012 at 10:39 PM.
Another ignition source
Another source you might try is flyefii.com. The parts are top notch and the engineering is quite good. I know of several airplanes flying with this system with no problems.
E-mag/P-mag user here, I'm not too impressed with the aircraft E.I. that are out there (p-mag is okay and getting better) but..... how many times has your electronic ignition in your automobile failed while in operation? My answer to that question was/is ....never, oh I've had a couple of failures but not while driving, I've also have (usually) had advanced warning that something was/is wrong. There are some great choices for DIY aircraft electronic ignitions, the Megajolt with the Ford edis parts is a favorite of many hotrodders with reliable results, I intend on using that system coupled with a P-mag on my current aircraft, the future of E.I. in experimentals is promising. Oh and for what it's worth Slick mags are pretty junky now-a-days and require the 500 hr inspection/overhaul at way too much costs for old tech.