I was wrong.....

cowman

cowman

Final Approach
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Cowman
So, after all the trouble I had getting my annual done it happened just before my big Christmas trip. We made it down to KY just fine.

I had been joking with people I knew this trip would happen because I would probably get stuck at my in-laws house for a week with bad weather.

I was wrong. It was the airport in between there and home and a faulty left mag. :mad2:

Posted from the passenger seat of our rental car.
 
What good fortune, you are in the passenger seat so you can start drinking...
 
Your not heading back to the in laws house,I hope. Glad it's only a minor problem.
 
Archer starts on the left mag. I learned that from the mechanic today.
 
It evidently quit sometime between when I started it up to taxi from the fuel pump to parking and when we returned from lunch.... not in flight.
 
cowman said:
It evidently quit sometime between when I started it up to taxi from the fuel pump to parking and when we returned from lunch.... not in flight.
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Fresh out of an annual...

Ya gotta love those "CERTIFIED , HIGH DOLLAR, FAA APPROVED safe parts..:yes:...:rolleyes:
 
WingNut42 said:
But things like electronic ignition might be dangerous..........:rolleyes2:
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I am baffled that we are allowed to start airplanes with electric starters. Surely a hand crank like cars used to have would be safer.

David
 
flhrci said:
I am baffled that we are allowed to start airplanes with electric starters. Surely a hand crank like cars used to have would be safer.

David
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:rofl::mad2:

Fortunately someone figured out the electric starter before we became afraid of the possibility that advancements in technology might offer safety improvements.
 
Funny you guys mention that....

The refuel/lunch spot I chose is also the airport I'm storing my future project/current ground transport vehicle- a 79 International Scout. It is only one year newer than my airplane. It came with factory electronic ignition. It still works....

Electronic ignition has been around for some 40+ years in the automotive world. I'd say calling it unproven is sort of like saying the electric light bulb is unproven so we'd better stick to candlelight.

That said a quote of around $400 for a drop-in mag replacement vs thousands for an STC and ignition swap in the field on zero notice with me wanting to get the airplane off that ramp and into a hangar somewhere... guess which way I'm going. :rolleyes:
 
cowman said:
Funny you guys mention that....

The refuel/lunch spot I chose is also the airport I'm storing my future project/current ground transport vehicle- a 79 International Scout. It is only one year newer than my airplane. It came with factory electronic ignition. It still works....

Electronic ignition has been around for some 40+ years in the automotive world. I'd say calling it unproven is sort of like saying the electric light bulb is unproven so we'd better stick to candlelight.

That said a quote of around $400 for a drop-in mag replacement vs thousands for an STC and ignition swap in the field on zero notice with me wanting to get the airplane off that ramp and into a hangar somewhere... guess which way I'm going. :rolleyes:
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..

I feel your pain since it is a certified plane, the FAA has ya by the balls...

Geico's people called and mentioned that I should suggest " get an experimental" "..:wink2:
 
A while ago I would have said the electronic ignition on the ROTAX 912 was virtually bulletproof. You just did not hear of failures.

But it seems like ignition modules from around 2006 to 2007 are just starting to have "issues". Rumor has it their solder joints of questionable longevity. The problem hit mine last year.

Good news is that the failure virtually always shows up on starting - once started they seem fine.

And in general, it's a well thought out system, not dependent on system voltage - each ignition has its own "generator", making it very "magneto-like" in practice.

However, the new injected 912is is dependent on outside power.
 
flhrci said:
How did Geico get "people?" Scary......



Sent from my iPad using Tapatalk HD
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It is a long story but the gist is....

He flew over their houses with the smoke system in his RV on,,, they came out and thought it was a chem trail and since then he had them eating out of his hand........

That lil green lizard is pretty clever...:D
 
FastEddieB said:
A while ago I would have said the electronic ignition on the ROTAX 912 was virtually bulletproof. You just did not hear of failures.

But it seems like ignition modules from around 2006 to 2007 are just starting to have "issues". Rumor has it their solder joints of questionable longevity. The problem hit mine last year.

Good news is that the failure virtually always shows up on starting - once started they seem fine.

And in general, it's a well thought out system, not dependent on system voltage - each ignition has its own "generator", making it very "magneto-like" in practice.

However, the new injected 912is is dependent on outside power.
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This is the essence of the problem with electronic ignition. When it fails, it FAILS. No spark, period. And it has several times as many failure points as magnetos.

Ignition module failure on start is a lucky break. Usually, they fail when the temperature changes a lot.

Now, I know someone who really doesn't understand shades of gray is going to respond to this with "but mags fail, too." Yes, they do. But they have many, many fewer failure modes, and a mag failure causing an in-flight engine failure is not at all a common occurrence. One set of mags blowing up is more common, but that's why you have two sets. Ignition failures causing car engines quitting is NOT rare. Virtually all mid-80s Fords with distributor mounted ignition modules suffer that at some point, for instance. And OBD-I VW's are known for eating coils.
 
MAKG1 said:
Ignition module failure on start is a lucky break. Usually, they fail when the temperature changes a lot.
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One of the "tests" of a failed module was to pack it in ice. Said to often get the engine running, from which point it would run until shut down.

I actually tried it, to no avail:

15988327080_4c75d638d2_z.jpg
 
cowman said:
Funny you guys mention that....

The refuel/lunch spot I chose is also the airport I'm storing my future project/current ground transport vehicle- a 79 International Scout. It is only one year newer than my airplane. It came with factory electronic ignition. It still works....

Electronic ignition has been around for some 40+ years in the automotive world. I'd say calling it unproven is sort of like saying the electric light bulb is unproven so we'd better stick to candlelight.

That said a quote of around $400 for a drop-in mag replacement vs thousands for an STC and ignition swap in the field on zero notice with me wanting to get the airplane off that ramp and into a hangar somewhere... guess which way I'm going. :rolleyes:
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If your scout has a total electrical failure, will it run?
 
They mounted the ignition module to the engine?

It's been known for some 30 years in cars that that's stuHOOpid. Ignition modules need to be in a moderately stable temperature, with some cooling as they generate their own significant heat. Excessive heat is much worse than excessive cold. The firewall is a much better place. Of course, that means running wires, each of which can fail.

Go through your car and see where the module is. If it's later than 1990 or so, odds are, it's not physically attached to the engine at all.

There is NO WAY I would trust an ignition module known to be failing in the air. Staying running until shutdown is a lucky coincidence at best. If it's a heat problem, the next time you do a Vx climb or departure stall practice, it's going to bite you.
 
MAKG1 said:
They mounted the ignition module to the engine?
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Yep. Piggybacked one over the other on all 912's, I think.

As a data point, when I installed my SoftStart module, it came with a temperature indicating strip as seen here, right before I removed the modules to install the new style:

15988534758_fb52417b73_z.jpg


Does not look like high temps are a concern, at least in my installation.

There is NO WAY I would trust an ignition module known to be failing in the air. Staying running until shutdown is a lucky coincidence at best. If it's a heat problem, the next time you do a Vx climb or departure stall practice, it's going to bite you.
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Agreed. I think some suggested the ice trick could get you home. I thought that was a bad idea and utilized it as a diagnostic tool. Mine did not start even with the ice trick.

BTW, those modules were typically $1,000 each. ROTAX dropped the price 50%, making the $1,000 for the pair. I guess they did it as a consideration to owners upgrading past, problematical modules to the new style.
 
MAKG1 said:
This is the essence of the problem with electronic ignition. When it fails, it FAILS. No spark, period. And it has several times as many failure points as magnetos.

Ignition module failure on start is a lucky break. Usually, they fail when the temperature changes a lot.

Now, I know someone who really doesn't understand shades of gray is going to respond to this with "but mags fail, too." Yes, they do. But they have many, many fewer failure modes, and a mag failure causing an in-flight engine failure is not at all a common occurrence. One set of mags blowing up is more common, but that's why you have two sets. Ignition failures causing car engines quitting is NOT rare. Virtually all mid-80s Fords with distributor mounted ignition modules suffer that at some point, for instance. And OBD-I VW's are known for eating coils.
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I'm gonna have to disagree with your premise a bit there. I'm familiar with the Ford ignition module you're talking about- I had to replace on once. That's been my only failed electronic ignition experience in many years of driving and working on many different types of automotive and agricultural equipment.

Yeah I'm gonna say it- mags fail too and from everything I've seen I think they actually fail a whole heck of a lot more often than solid state electronic ignition. I see posts here about mag failures constantly, I've seen people stating that they're only really reliable for about 500 hours then they should be inspected and/or overhauled. Translate that to an automotive application- that's the equivalent of what 30,000-50,000 miles? Imagine that kind of failure rate in the automotive world. The car would be considered extremely unreliable. Nobody would tolerate that kind of failure rate in a car, they might even get recalled.

Any system will fail though. Sure the electronic system has many more failure points but the odds on any given flight of one failing are pretty darn low. That's why we have two separate systems. The odds of both them going out on any one flight have to be approaching lottery winner territory.

I suppose all of this is all anecdotal without some data and a controlled study but if I had the choice and I were to chose whether to bet my life on old mags or solid state electronic ignition, I'd absolutely bet on the electronic system.
 
Tom-D said:
If your scout has a total electrical failure, will it run?
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That's a fair point, but I can't ever remember having heard of a situation where someone's alternator died and they didn't have enough juice in the battery to get to the next service station.

Heck my dad had a tractor with a bad generator and electronic ignition and we just charged up the battery before taking it into the field rather than fix it. Ignition uses very little juice...

But still you have a valid point, aircraft seem to suffer electrical failure disturbingly often. I believe they require a secondary backup battery in the kits for experimental where both mags are replaced for that reason. Maybe leaving one mag in isn't a terrible idea. I'd still rather go solid state though...
 
cowman said:
That's a fair point, but I can't ever remember having heard of a situation where someone's alternator died and they didn't have enough juice in the battery to get to the next service station.
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Total electrical failure is not the same as an alternator failure.

As a counterexample, my C-10 had its idle solenoid fail shorted. That burned out the 12V "bus" (actually, just a wire in that model). No 12V power, but the alternator was fine. No, it didn't run. No coil primary.

This failure in an airplane might cause other problems, but it would not cause the engine to quit.
 
cowman said:
I see posts here about mag failures constantly, I've seen people stating that they're only really reliable for about 500 hours then they should be inspected and/or overhauled.
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Sure you do.

And the results of the failure are that the engine runs a bit rough or may require limping to an airport on one set. Or may make you cancel a flight if it shows up at run-up.

That's FAR short of a failure that makes your engine quit without warning.

The essence of your argument is that slightly rare catastrophic failures are better than fairly common but much milder failures. I would disagree with that rather strongly.
 
MAKG1 said:
The essence of your argument is that slightly rare catastrophic failures are better than fairly common but much milder failures. I would disagree with that rather strongly.
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With 2 independent ignition systems for redundancy, no I'm not really worried about having one of them fail suddenly rather than gradually if in exchange I get far better overall reliability and probably greater fuel efficiency and easier starts.
 
cowman said:
With 2 independent ignition systems for redundancy, no I'm not really worried about having one of them fail suddenly rather than gradually if in exchange I get far better overall reliability and probably greater fuel efficiency and easier starts.
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Do those two independent systems come with independent engine driven charging systems and batteries as well?

Can you guarantee that it is impossible for any part of the ignition system to fail to a short to ground?

If not, they aren't independent, and your risk analysis is invalid.
 
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MAKG1 said:
Do those two independent systems come with independent engine driven charging systems and batteries as well?
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As I understand it, the systems they're using in some experimentals have exactly this built in.

Can you guarantee that it is impossible for any part of the ignition system to fail to a short to ground?

If not, they aren't independent, and your risk analysis is invalid.
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I guess I can't. Better go trade in my modern car for a more reliable model T Ford and stop flying these dangerous airplanes.


... or just let me put electronic ignition in my own airplane and you can keep your mags and we can all go home happy. :yesnod:
 
cowman said:
Better go trade in my modern car for a more reliable model T Ford and stop flying these dangerous airplanes.
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Wow. That's really over the top.

Your car engine quitting won't kill you unless you're an idiot. It may **** a few people off, and it sucks, but that's about it. And it happens ALL the time.

Your airplane engine quitting can be quite a lot more serious than that, depending on where you are when it happens.
 
MAKG1 said:
Wow. That's really over the top.

Your car engine quitting won't kill you unless you're an idiot. It may **** a few people off, and it sucks, but that's about it. And it happens ALL the time.

Your airplane engine quitting can be quite a lot more serious than that, depending on where you are when it happens.
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Well, it's an aviation forum on the internet, over the top seems appropriate.

The point is all your concerns can be addressed or at least mitigated with basic insulation/protection circuitry and the redundancy of having two systems. If you take what the auto industry has and apply aviation standards to it, I still believe you'd have a safer system.

Also recognizing this is all hypothetical until we're looking at a specific unit and doing some testing and analysis on it.
 
MAKG1 said:
Ouch. A quick review of that thing shows a single point failure in the "power management unit" as it passes everything through a single cable.

Backup power doesn't do you any good if it gets disconnected along with main power.

I hope they fix that in the next revision.
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Single point failures, try shorting out your mag switch see what happens.
 
MAKG1 said:
This is the essence of the problem with electronic ignition. When it fails, it FAILS. No spark, period. And it has several times as many failure points as magnetos.

Ignition module failure on start is a lucky break. Usually, they fail when the temperature changes a lot.

Now, I know someone who really doesn't understand shades of gray is going to respond to this with "but mags fail, too." Yes, they do. But they have many, many fewer failure modes, and a mag failure causing an in-flight engine failure is not at all a common occurrence. One set of mags blowing up is more common, but that's why you have two sets. Ignition failures causing car engines quitting is NOT rare. Virtually all mid-80s Fords with distributor mounted ignition modules suffer that at some point, for instance. And OBD-I VW's are known for eating coils.
Click to expand...

TFI on the Fords was definately unreliable.

Since then...coil packs...EDIS...now coil on cylinder....just about bulletproof. Ignition failures are beyond rare now.
 
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