# Spark redundancy.

### Help Support HomeBuiltAirplanes.com:

#### Daleandee

##### Well-Known Member
Corvairs have been flying for 40+ years without twin spark plugs per cyl..
Actaully it been over 60 years as Bernard Pietenpol put one on his plane in 1960 and thus was the first to fly a Corvair!

As to the FAA discussion in progress, Corvairs don't really count as they are experimental engines. But your point it is well taken.

Modern Corvairs have dual ignition but still retain the single plug per cylinder. Loosing a cylinder on a six cylinder is a bit more negotiable than loosing a cylinder of a four cylinder ...

#### Jerry Lytle

##### Well-Known Member
I flew my 170A on a signed off ferry flight to get a new annual some 300 miles away. The IA there owed me some money. Half way I felt the engine was a little rough, check the mags, one side was dead. Went on to land at the destination. Next morning I was going to move the plane over to the shop and it would not start. Both mags were dead. Turned out it wasn't the mags themselves but on both of the old loomed grounding wires insulation had disintegrated while in close contact to a grounded structure, but at different locations. A few months prior to this I had taken that same plane on a three hour night flight Eugene to Seattle, it never missed a beat.

#### Dan Thomas

##### Well-Known Member
I flew my 170A on a signed off ferry flight to get a new annual some 300 miles away. The IA there owed me some money. Half way I felt the engine was a little rough, check the mags, one side was dead. Went on to land at the destination. Next morning I was going to move the plane over to the shop and it would not start. Both mags were dead. Turned out it wasn't the mags themselves but on both of the old loomed grounding wires insulation had disintegrated while in close contact to a grounded structure, but at different locations. A few months prior to this I had taken that same plane on a three hour night flight Eugene to Seattle, it never missed a beat.
That sort of thing happens far too often. It's due entirely to shoddy inspections and maintenance, and that laziness or cheapness causes far more system failures than the ancient technology does. The non-mechanics blame the technology; the experienced, diligent mechanics know better because they so often find dangerous stuff like worn P-leads. I have lots of horror stories about worn-out or poorly-repaired stuff.

#### pfarber

##### Well-Known Member
Well, p, you were wrong.

If you don't want to fly behind a Lycoming, by all means power your HBA with something else. Meanwhile, thousands of us are actually flying E-AB aircraft powered by Lycoming and or Lycoming clones. Whining will get you nowhere.

BJC
Lyc said "The Lycoming EIS was developed by SureFly Partners, Ltd "

What part did I get wrong?????

I get that Lcy are certified under a decades old certification and legally, to modify them, would take a lot of legal work.. or the FAA could simply say 'we know this works, use this'.

I would fly behind anything if it works well.

#### BJC

##### Well-Known Member
HBA Supporter
What part did I get wrong?????
You wrote that [Lycoming] still won’t offer fully electronic ignitions ...
Even now, lycausur still won't offer fully electronic ignitions even though they are perfectly fine and STCs have had almost no issues.
Lycoming does offer a fully electronic ignition. See LYCOMING EIS

Tell us what engine powers your airplane.

BJC

BJC

#### pfarber

##### Well-Known Member
You wrote that [Lycoming] still won’t offer fully electronic ignitions ...
Lycoming does offer a fully electronic ignition. See LYCOMING EIS

Tell us what engine powers your airplane.

BJC
You like word puzzles? me to! SureFly owns the STC, not Lycoming, so basically Lyc did nothing except print a logo on the side of SureFlys STC'd part. So tell me what great step did Lyc do other than mark up and resell something you can get cheaper, elsewhere?

The 'iE2' engine is only on a kitbuilt Lancair, so its not even used on certified AC.

By your logic, I can buy a Ferrari sticker from Alibaba for $0.99 and now my car is an F40? #### pfarber ##### Well-Known Member Once again, this one, too, which is not an ordinary Lyc with two electronic magnetos on it: iE2 Integrated Electronic Engine View attachment 108967 And the number of AC that use this engine is????? Its like a Lycoming MLM scheme here now. Lets point at the most far fetched tenious thing we can find and say that its completely normal. Wonder what Surefly gets per unit royalty with a Lyc decal on it. #### Dan Thomas ##### Well-Known Member And the number of AC that use this engine is????? Its like a Lycoming MLM scheme here now. Lets point at the most far fetched tenious thing we can find and say that its completely normal. Wonder what Surefly gets per unit royalty with a Lyc decal on it. It's not in many airplanes because the governments demand recertification of the whole package--airframe and engine installation--and that costs a lot of money, which doesn't go over well on models that see a few dozen units per year. You claimed that Lycoming didn't offer any electronic ignitions systems, and we showed you two reasons you were wrong. And you think the iE2 is only on a kitbuilt Lancair? Didn't you check Lycoming's website? Wrong again. #### Urquiola ##### Well-Known Member You know the Series A Citroen cars: 2CV; Ami; Dyane; Mehari, had a twin flat, last of 602 or 652 cc, air and oil cooled engine, with no distributor, an spark lost every cycle. Savoiacars.com in Argentina proposed avionized versions of it. Blessings + #### TiPi ##### Well-Known Member Log Member You know the Series A Citroen cars: 2CV; Ami; Dyane; Mehari, had a twin flat, last of 602 or 652 cc, air and oil cooled engine, with no distributor, an spark lost every cycle. Savoiacars.com in Argentina proposed avionized versions of it. Blessings + that is very old hat, BMW has been doing this for a long time on their boxers. It works on even-cylindered engines with 360deg firing spacing between opposed cylinders (flat twin, flat boxers, V6 and V8). Even B&S used the double-ended coil (2 HT outlets) on their flat twins. #### Daleandee ##### Well-Known Member Even B&S used the double-ended coil (2 HT outlets) on their flat twins. The VW conversion engines from Sonex use two of the old Briggs& Stratton "L-Head Twin Engine coils" for their primary ignition source. #### Dan Thomas ##### Well-Known Member that is very old hat, BMW has been doing this for a long time on their boxers. It works on even-cylindered engines with 360deg firing spacing between opposed cylinders (flat twin, flat boxers, V6 and V8). Even B&S used the double-ended coil (2 HT outlets) on their flat twins. I have that system in my Ford Ranger, on its 4L V6. Three coils in the pack, six plug leads. If one sparkplug or lead fails open, neither plug on that coil will fire. The circuit is from ground to spark gap on the first plug, through the lead to the coil, through the coil and the other lead to the spark gap on the second plug, and to ground again. On a four-banger you'd lose two cylinders, which is more like losing three since the remaining two have to pump the dead two back and forth through all their cycles. Waste-spark is a cheap way to build the ignition system. Cheap and safe are often mutually exclusive. I had one coil fail years ago on my old Chev Cavalier, and more recently a lead fail on the Ranger. In both cases the the loss of power was big. #### Daleandee ##### Well-Known Member On a four-banger you'd lose two cylinders, which is more like losing three since the remaining two have to pump the dead two back and forth through all their cycles. I'm a Ranger driver myself ('02 4-cylinder) and I can surly verify that when my coil pack cracked and I lost two cylinders it was tough to get the truck to the house to replace the pack. OTOH it has been an extremely reliable vehicle. #### pfarber ##### Well-Known Member It's not in many airplanes because the governments demand recertification of the whole package--airframe and engine installation--and that costs a lot of money, which doesn't go over well on models that see a few dozen units per year. You claimed that Lycoming didn't offer any electronic ignitions systems, and we showed you two reasons you were wrong. And you think the iE2 is only on a kitbuilt Lancair? Didn't you check Lycoming's website? Wrong again. View attachment 109008 Not in the US, so no, it doesn't mean a thing. Unless they certify the engine/STC it then its an Albatross.. just like diesel motors that cost$500k.

So many people look for that one minuscule tenious link that it becomes kinda sad. Face it, unless Lyc STC's them into old airframes (good luck with that) or a new company does it for them (more likely) these motors are still pipe dreams... and STILL not up to what a car motor can do.

#### Riggerrob

##### Well-Known Member
First off, I suggest that you apply a bulldozer - and maybe dynamite - to that little knoll 2/3 of the way down your runway. That will remove one landing hazard and provide enough "fill" to straighten another section of your runway. It still looks like a one-way airstrip.

Secondly, may I suggest that you start with a turbo-charged Rotax 914 or 915 engine? The turbo-charger will help - at your altitude - because normally aspirated engines lose power above 5,000 feet MSL.

Thirdly, you can still position the pilots' eyeballs ahead of the wing if you build one of those airplanes with slightly swept forward wings. The last time I traded letters with Bert Sisler, he was installing a Rotax engine in the Cygnet prototype. Cygnet is the prettiest airplane in its class.
Another option is the Australian "Hornet" which looks similar to the Cygnet except that it is made of sheet aluminum. If building either airplane, ask the designer about extending wingtips to improve climb rates.

As for steep approach angles ... may I suggest installing wing spoilers similar to sailplanes. Spoilers will allow you to fly steep approaches - with some power (like naval airplanes) - but retract them just before a soft ouch-down. Once wheels are firmly on the runway, redeploy spoilers to allow you to apply brakes earlier to shorten roll-out.

#### Dan Thomas

##### Well-Known Member
Not in the US, so no, it doesn't mean a thing.

Unless they certify the engine/STC it then its an Albatross.. just like diesel motors that cost $500k. So many people look for that one minuscule tenious link that it becomes kinda sad. Face it, unless Lyc STC's them into old airframes (good luck with that) or a new company does it for them (more likely) these motors are still pipe dreams... and STILL not up to what a car motor can do. Not in the US so it's not significant? As if all the advances in aviation have been American? Obviously, they felt it was worthwhile pursuing this, and they must sell enough airframes to justify it. Maybe the Italians don't have so many lawyers, too. I can't see anyone on this side of the pond investing many millions developing STCs for the 300-hp class, considering that they're in the minority in GA, and then having to buy liability insurance to cover themselves forever. The conversion cost would far outweigh the cost of the airplane, just like the SMA diesel 182 conversion takes a$75K airplane and turns it into a $175K airplane. Not much market here for that. In Africa 100LL is scarce and terribly expensive, while Jet-A is plentiful, so some operators there uses the SMA 182. I did some work on one that was then shipped over there. #### pfarber ##### Well-Known Member GAMA, in 2016, noted that the USA had over HALF of the GA aircraft on the PLANET So if there is small company in lower wherever-istan doing something unique, its not going to be a thing that the MAJORITY of GA can use. Granted, there are companies like Vans E/AB that are registering 300+ new planes a year, but even Vans isn't going anything unique or 'forward thinking'. They don't even recommend conversions... even though many hundred RVs are flying behind a car motor. Its hilarious that Vans has this quote on their engine web page: “The best conversion I know is to take$8000 and convert it into a good, used Lycoming.”

How out of touch are you to think that there is a good, used Lyc for $8000????? And this is from the undisputed leader in kit AC. If they DO have a stash of O-360s for$8k, I'll take two, please.

I get that there are exotic engines like diesels and electrics, but they are not solutions, they are more like pet projects that somehow didn't get cancelled and know its like 'well, maybe someone will spend this much money for some unknown reason'.

Whats hilarious is that every motor in GA now is long, long past patent protection. You could reverse engineer an exact copy, legally, and and long as you don't call in a Lycoming O-360 or whatever you are 100% legal (remember how generic drugs work???) Yet to circumvent patents the FAA dreamt up this PMA and made the rules read you HAD to use the exact same part number (aka used copyright) to prevent a great expansion of engines... and to allow Lcy and Cont to basically screw GA with higher prices and ZERO innovation.

Even when you look at Lyc's 'experimental' engines (non-certified for E/AB use) there is such a tiny cost savings that's its laughable that they went through the trouble to even do it.

#### Dan Thomas

##### Well-Known Member
Whats hilarious is that every motor in GA now is long, long past patent protection. You could reverse engineer an exact copy, legally, and and long as you don't call in a Lycoming O-360 or whatever you are 100% legal
Superior did that. It was still expensive. The production volumes are just too small, and even doubling or tripling a small number still gives a small number. And if we get two or three companies making the same thing, the production at each place goes down and they have to charge more or go broke which is what happens and you're back to one supplier.

#### dwalker

##### Well-Known Member
In most aspects, my personal use of conversion engines rather than conventional aircraft engines has less to do with buy-in economy and much more influenced by running cost and technology. Most people, if they are honest, will admit that an auto conversion is not initially cheaper than a used Lycoming. The costs start mounting when you have to rebuild the mags often, perform top end rebuilds, etc. after relatively low hours in your homebuilt because well, you bought a used motor. At that point, the auto conversion that was a fresh rebuild really starts to earn its keep.
The redundant systems argument for certified "aircraft" engines remains something of a mystery to me. All auto conversions I am aware of- and that is not to say I am aware of them all, I am especially fuzzy on V6 and V8 auto conversions- have spark redundancy developed for them. Many use electronic fuel injection which is so much more reliable than a carburetor that even ignoring the efficiency and control provided by EFI it is laughable to attempt to argue a carb is in any way meaningful way safer or better. The fact is that GA would have converted a decade ago if the FAA had not, as per usual, made it so prohibitively expensive that to even consider it makes your bank account slit its wrists.
And no, I am not ignoring the "old school" generation which maintains that "all they need to fix a carb is a screwdriver and a set of pliers,but would not know where to start with EFI", I am just saying they are wrong. When I connect to my EFI via computer it not only tells me what is wrong it tells me why. If I have a coil- one per cylinder or two per rotor- on its way out the ecu know it, and will prompt replacement long before failure. In fact, the ecu I tend to use communicates via canbus to a dash and or logger- thats a "flight recorder" or "black box" every single parameter, ever single revolution, in milliseconds, the entire time it is on. That data is then downloaded, and I can see everything that happened during an entire flight, race, start-up, etc. Injector pw, battery levels, cht, egt, wideband 02, spark duration, coil dwell,- it is all available. Now lets say that during a flight you notice an off noise, or delay in power delivery, or whatever, but its intermittent or only happens once or twice. With the log file, you can see everything that was happening during that period. Maybe the#1 knock sensor went active, indicating that its time to decarb the valves or you got some crap fuel. Maybe the #3 CHT sensor was reading a little high for a minute or two then settled down. Maybe fuel pressure skipped and its tie to clean the filter.
The point is that in a Lycosaurus you might have noticed, checked it out, and found nothing at all, then a few flight hours later had a bad time.
Because saying "that's the way we have always done it" is a horrible thing to say.