Mag Failure....

In this months issue of EAA's Sport Aviation mag Mike Busch speeks of Mag failures. My question is does the Mag failures he speak of happen to new mags or low hr mags or just any mag at any given time.

I ask this because like myself I am sure a lot of others are flying in experimental homebuilts that do no have this redundancy that is found in certified airplanes.

I can only speak for myself but I bet others think the way I do. Meaning we use mags because they are more reliable then a distributor and because I do not use a redundent system I keep my equipment in very good condition. Things like mags get replaced at the time of airplane purchase " I do not build " with new. I am very picky when it comes to mag replacement. Because of this I use the best mag shop I can find.

So doing this I hope to reduce the chance of a mag going bad. But when I read articles like this and do other research, the impression I get is that if I am not using a redundent ignition system I am going to fall out of the sky.

Now after reading and learning a little about aviation and the pit falls of it...is the mag any better..or is it that a part has been left in service to long and that is why we see gears fail and other things go wrong with a mag, or is it bad luck?

Maybe the title should have been.....Are we all doomed to crash flying with single ignition......


Thoughts from everyone would be great.......


H.A.S.

Since no one else has spoken up, I will offer some comments about Mike B's article. I just got my copy of Sport Aviation today. Perhaps other folks have not received theirs yet and will comment after they digest it.

My first take-way, being the critical and opinionated guy, is that Mike described a group of pilots who do not understand the mechanical workings of their equipment and so turned a mere problem situation into a full blown crisis. That is a little hard on those guys but what I read suggests that they had the knowledge of how to handle an ignition system problem but under pressure were unable to apply that knowledge. In fairness, none of us knows how we react under cockpit stress until it finds us, but study and preparation are supposed to give us the ability to focus on the issue at hand and do some analysis rather than immediately go to the bottom of the engine failure checklist and prepare to crash.

So my first suggestion is that pilots, especially those who might have only one of a flight critical system on board, need to really understand their equipment, how it operates, and how it can stop operating. That knowledge, combined with the resolve to go through the trouble shooting steps on the checklist, allows you to make rational decisions that can keep a system issue just a large problem and not a full blown crisis, or allows you to recognize when you do have a real crisis and need to move farther down the checklist.

Magnetos are simple devices that have been made very reliable so long as they receive enough maintenance. Pilots can go many many years and never have a magneto problem in the air. That is because we know what wears, what temperature range they like, and what happens inside as we climb to higher altitudes. Their behavior is very well understood in general. That's what Mike B's article essentially says. The question is whether the equipment's behavior is well enough understood by all of the pilots riding behind them.

As the owner of home built aircraft that has a single ignition I have to assume that you are both the flight and maintenance department. As such, you are tasked with doing on the ground what your ignition system needs in order to always run reliably aloft. Do the recommended maintenance and replace the parts that wear and you should be fine. I will also note that a number of models of mags have FAA Airworthiness Directives mandating inspections and parts replacements if those mags are installed on a certificated aircraft. This is a case where you should read, understand, and follow the instructions in those AD's. They were published to correct real problems and are ignored at your peril.

So as with many things in aviation, if you do your part, the airplane, and its ignition system will do its part. If you are using a good shop and take care of your mag, it will likely take care of you.

As for the pit falls of aviation, I will observe that leaving the ground involves the risk that you may not enjoy or even survive coming back to earth. Everyone has a different tolerance for risk vs reward. Risk is managed by knowledge and judgement. My body of knowledge allows me to confidently stand in the open door of an airplane and step into tens of thousands of feet of empty space, at night, on New Years Eve, with a universe of stars twinkling at me marking the beginning of a new year. Or be driving a vertical down line in the aerobatic competition box, approaching both pattern altitude and the airframe red line, rolling. But you may get an equal amount of reward cruising along in level flight on a calm weekend morning watching the fog clear in the valleys on the way to a pancake breakfast. Different but equal reasons to enjoy aviation. That said, if airplanes will do what a guy like me asks of them and bring me safely back to earth, I will suggest that you can go flying with confidence in your machine.

Best of luck,

Wes
N78PS

Wes very good reading indeed. What you speak of is why I wanted to go with a new mag when I purchased my airplane. Doing this I feel that a few years of trouble free operation are ahead of me.
You are so right I am not only the pilot but mechanic, so its up to me to keep that mag in top shape. Saying this how often would you open it up and check the points, every condition inspection or so many hrs.
Speaking of Mike B. I value every word he says and have nothing but respect for him and others on this forum like yourself.

H.A.S.

Your maintenance questions have answers in the manufacturers manual for the part that you are looking at. There are service manuals for magnetos, carburetors, the engine, etc., and many are available online. Google is your friend. Simply follow the manuals. Not complicated unless you make it so. And for general guidance, get a copy of AC43.13.

Best of luck,

Wes
N78PS

Quote:

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Originally Posted by WLIU

Your maintenance questions have answers in the manufacturers manual for the part that you are looking at. There are service manuals for magnetos, carburetors, the engine, etc., and many are available online. Google is your friend. Simply follow the manuals. Not complicated unless you make it so. And for general guidance, get a copy of AC43.13.

Best of luck,


Wes
N78PS

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Wes I never even thought to look for this info. The reason is my mag is made for a tractor. Its just a little twin cylinder tractor mag. Would I still find info on this mag in the aviation forums you speak of.
I bet others think like I do. if its not a certified avaiton part there will be no info from the FAA on it. Is this correct thinking?

Magneto is just another component. Maintain it like the other component and it will provide long, reliable service.

I would echo Wes's words regarding inspections and maintenance. I've been a club flyer for 20 plus years and have never experienced a Mag failure. Both of the clubs I joined follow Flight School maintenance programs with Hobbs meters driving preventative maintenance, along with "Squark Books". These are certified aircraft and get flown by more the one person with annual hours of about 100 on each aircraft. If you own and fly any aircraft you will have to factor in maintenance as part of the cost of ownership, looking to cut costs should not be the driving force in the maintenance arena.

Joe

Quote:

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Originally Posted by Joe LaMantia

I would echo Wes's words regarding inspections and maintenance. I've been a club flyer for 20 plus years and have never experienced a Mag failure. Both of the clubs I joined follow Flight School maintenance programs with Hobbs meters driving preventative maintenance, along with "Squark Books". These are certified aircraft and get flown by more the one person with annual hours of about 100 on each aircraft. If you own and fly any aircraft you will have to factor in maintenance as part of the cost of ownership, looking to cut costs should not be the driving force in the maintenance arena.

Joe

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Well I have about 50 hrs and two years on my mag as of today. I have not done anything to this mag since installed new. I did not buy a rebuild but a new mag. I made sure this mag spent its time on a shelf in a wooden box not just thrown on a shelf in a cardboard box.
Not sure what else I should be doing to this mag. As Mike says not all maint. is good maint. Its working so leave it alone? Its relatively new so leave it alone?

If it is that new, I would not mess with it.

Now if it is a mag for a tractor, find out what make and model it is used on, identify the engine, and you will find that there is a book for that engine that likely mentions the mags. Or your tractor dealer can find you a book just for the mag. Personally, I have a Kubota 2910 diesel so I don't have to worry about a mag, but I will bet that you can get the info that you need through a tractor dealer or manufacturer.

Slick mags started as tractor mags. If all else fails, I would use their maintenance instructions as a guideline.

Best of luck,

Wes
N78PS

Quote:

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Originally Posted by WLIU

If it is that new, I would not mess with it.

Now if it is a mag for a tractor, find out what make and model it is used on, identify the engine, and you will find that there is a book for that engine that likely mentions the mags. Or your tractor dealer can find you a book just for the mag. Personally, I have a Kubota 2910 diesel so I don't have to worry about a mag, but I will bet that you can get the info that you need through a tractor dealer or manufacturer.

Slick mags started as tractor mags. If all else fails, I would use their maintenance instructions as a guideline.

Best of luck,

Wes
N78PS

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Wes this is some more great info that I am sure not only I will use....

I would have to look in my log book to see what mag that was but it was not a slick, it seemed to me it was a two name company and it started with a P. I should know this.

I had no idea how old that mag was in my airplane when I purchased it. For all I knew the builder pulled that mag from a 50 year old tractor and stuck it on this airplane. So I teated that mag as a 50 something year old mag and it looked the part.

When I took this mag off, the cap had been JB welded back together. They did a good job and even painted it black, but a big portion of that cap was JB weld, it lost a corner and they remade it with JB weld. I then found the points where submerged in oil. The seal on the end had gone bad and half filled the inside of the mag with engine oil, and this engine ran, I flew the plane a couple times before I replaced this mag.

When I found this I knew I wanted a brand new mag. I did a lot of research and found some sell 50 year old mags as new mags. They are indeed new never used but they are 50 year old stock. I did not want one of these mags, I wanted a brand new mag made within the last 10 years. I found a company and the man makes these mags as needed. He reenergizes the magnets, he said a lot of shops do not do this and the magnets get weak and of course replaces parts. He then puts this mag in a thick wooden box and sets it on the shelf.

So now I have a new mag. I surely do not want to screw that up so this is why I ask if I should do anything to it. I thought at about the 5 year mark or 500 hr mark I would check points and such.

I have never had a mag in anything so I really no not how to handle her. I was told trouble free is what a mag is, then I hear Mike speak and I thought, maybe what I have been learning is not correct. Then I thought maybe these are mags that have been left in service to long. If one replaces or repairs these mags on a timely manner would this type of failures not be far and few between for a mag really is trouble free when in a new state or not decades old.

If I got into an airplane and asked the owner when was the last time he replaced his mag with new and he said never and the plane had 2000 hrs on it and 40 yrs old, I am not to sure I would fly in it for any length of time, a small hop to get a meal maybe, fly to say Oshgosh...no way by gosh...lol


Thanks agian......

HAS, I think you're are worrying about nothing. You're flying behind a converted VW engine that's been sawed in half and you're worried about the magneto failing?

I don't see how any aviation guidance is going to help you, your mag has no aeronautical service history. Just inspect the mag at regular intervals, every 50 or 100h, as you are comfortable. Pull the cap off, inspect the coil, wiring, points, cam, wear block and check the timing. Replace parts that wear, before they wear out, lubricate and adjust as necessary and keep records on what you find. At 500 hrs plan on complete dissassembly, inspection and rebuild. By then you'll have enough service history to know what's going on.

There are a lot of VW conversions flying with a Vertex magneto in the std distributor hole and these guys have enough experience to know a Vertex mag will last ~1000h in aviation applications. But they reguire routine inspection and maintenance to get there.