Had my first inflight magneto failure yesterday

I admire what you dog pilots are doing, dog lover myself. But I have to wonder why this is necessary. Can't these dog people find homes for the doggies closer to where the pups are? Why are they able to find homes a long way away but not locally?

I have visions of two plane loads of dogs going in opposite directions and simply exchanging one bunch of dogs for another.
 
Zeldman said:
The one incompetent mechanic that is also the DOM, with a lot of help from a real mechanic found that the key switch had failed shorting out the mags.
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In your case, I'd suspect that the ignition switch was an ACS or Gerdes. There is an AD on those that is overlooked 90% of the time. Mechanics keep assuming that all mag switches are Bendixes and keep doing the AD check on them that has no relevance to the ACS AD. I can't count the times I have found that bendix check year after year after year in the logs, and a quick look at the switch reveals that it's an ACS, and the AD (and required mods) have never been done. The starter contactor puts out a voltage spike when released, and it causes an arc on the switch contacts, burning them. Since there are moving contacts in there that are common to both the mags and start, trouble awaits. A diode on the contactor is required to shunt the spike.
 
Glad everything turned out ok. Had a mag failure in a rental 152 years ago just after takeoff with no remaining runway. Switched to the operating mag, but could not climb at all. It did run well enough to make it back to the runway at 300AGL. I had dirt roads as an option ...
 
Dan Thomas said:
Not only that. How many years? They suffer internal corrosion, cam grease dries out, coils crack.
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Point was it was probably run to failure, rather than periodic maintenance as required by service bulletin.
Awe hell we don't need to do that stuff, it ain't required.
 
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Mason said:
I admire what you dog pilots are doing, dog lover myself. But I have to wonder why this is necessary. Can't these dog people find homes for the doggies closer to where the pups are? Why are they able to find homes a long way away but not locally?

I have visions of two plane loads of dogs going in opposite directions and simply exchanging one bunch of dogs for another.
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Unfortunately not - I work with rescues in the south, and meet them in VA to bring animals up to the NE for rescue. There is a large animal overpopulation problem in the south; is this the answer? absolutely not - however it saves just a few from euthanization by getting them to no kill shelters up here.

Dan Thomas said:
Not only that. How many years? They suffer internal corrosion, cam grease dries out, coils crack.
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The rentals I use are also used for flight training, so they fall under the stricter maintenance inspections; I haven't gotten the full diagnosis back yet as the aircraft is not repaired yet, however at this time they are suspecting the magneto from a basic testing perspective but won't know for sure until torn down and repaired.
 
Mason said:
I admire what you dog pilots are doing, dog lover myself. But I have to wonder why this is necessary. Can't these dog people find homes for the doggies closer to where the pups are? Why are they able to find homes a long way away but not locally?

I have visions of two plane loads of dogs going in opposite directions and simply exchanging one bunch of dogs for another.
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As Paul said, it's effectively all one-way. The overpopulation issues are in the south, and the need for healthy, adoptable pets are in the north. This is mostly due to culture and a bit to climate. In the south, people don't spay and neuter their pets nearly as regularly. In the north, it's done almost universally.

There's also the climate. You have significantly more stray dogs in the south, which aren't spayed and neutered and thus increase their population. While dogs certainly can survive northern winters, you don't have as many. Plus, I think animal control in the north typically does a better job of capturing stray dogs. The flights south are the dead-head legs, the flights north are full.

Sometimes Florida can be both a sending and receiving state, but even then it's pretty rare. I've had transports to Florida, but they were usually high-profile transports such as when an animal testing lab in North Carolina (a sending state) was shut down and I flew an Aztec full of beagles to Florida. I've also gotten requests of sending dogs from Florida, but those have rarely panned out. You'll sometimes have specialty breeds, for example greyhounds are typically in a few states where greyhound racing is still popular (one of which is Florida) and then go to rescues around the country that specialize in greyhound adoption.

I've only once had a trip where I had dogs going both ways, but even that made sense. I flew a bunch of large dogs that were older and generally considered unadoptable to Best Friends Animal Sanctuary in Utah. I then went to LA and flew 47 chihuahuas to New York City. In both cases, it made sense. Best Friends will take in animals that are generally unadoptable, and then California has an overpopulation of chihuahuas (which became popular in NYC and SoCal after "Legally Blonde" came out).

I didn't understand the need until I got into it. When I was working with some contacts at the ASPCA a few years ago, they said that they did the math and determined it is possible to end euthanasia with transports. However, the catch is logistics (both transport and pairing the senders/receivers) and funding the operation. Realistically transports will never save them all (millions per year), but it will save the ones it will save.
 
Dan Thomas said:
In your case, I'd suspect that the ignition switch was an ACS or Gerdes. There is an AD on those that is overlooked 90% of the time. Mechanics keep assuming that all mag switches are Bendixes and keep doing the AD check on them that has no relevance to the ACS AD. I can't count the times I have found that bendix check year after year after year in the logs, and a quick look at the switch reveals that it's an ACS, and the AD (and required mods) have never been done. The starter contactor puts out a voltage spike when released, and it causes an arc on the switch contacts, burning them. Since there are moving contacts in there that are common to both the mags and start, trouble awaits. A diode on the contactor is required to shunt the spike.
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Thank you, I did not know about the AD. I'll keep a closer watch at the work the incompetent DOM does. That was not the first time a plane he signed off on then had problems on the next flight.
 
Amateurs... Try flying an O-320H2AD with a single shaft mag that was just reinstalled but not properly tightened on your fourth solo (first out of the pattern) and see what happens.

Mine resulted in a forced landing and a lawsuit that I lost and a soiled pair of britches.

All jokes aside...thank GOD you handled it better than me and can live to tell your story.
 
Zeldman said:
Thank you, I did not know about the AD. I'll keep a closer watch at the work the incompetent DOM does. That was not the first time a plane he signed off on then had problems on the next flight.
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Please tell me how any one can tell there is an impending failure like this mag switch coming up?
Many times the pilot will hear and feel things the A&P never sees or hears about, until the pilot has their Adrienne off the scale
 
One more thread that's been trashed Way to go POA.
 
Tom-D said:
Please tell me how any one can tell there is an impending failure like this mag switch coming up?
Many times the pilot will hear and feel things the A&P never sees or hears about, until the pilot has their Adrienne off the scale
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50 or 60 years ago motor vehicles were much less reliable and took more skill to start and drive, and needed servicing often. Many owners did a lot of their own maintenance and were acutely aware of what the vehicle was telling them at any given time.

Now we have vehicles that pretty much look after themselves and almost never fail us. Same with a lot of other devices. So now we have a couple of generations of drivers that don't have that long-lost awareness, and they learn to fly. They think nothing of some odd vibration or noise or funny feel to the airplane, something that wasn't there before. They might not even notice it. I used to fly the flight-school airplanes once in a while, and would find some stuff that needed fixing. The instructors would say "oh that? Been doing that for awhile. Wondered what it was." No curiosity, no sense of caution when faced with something out of place.

Airplanes are still running on very old technologies, they need the regular care those old things did but often don't get that care, and they are absolutely guaranteed to fail if let go like that long enough. And some owners of these machines tend to think that they should last like their cars do, without expensive inspections, figuring that if it's running OK, it will continue to do so. Unfortunately, we are probably a long way from having airplanes as advanced and reliable as our cars, simply because we're such a tiny segment of the motorized public. Avgas production is something less than 1% of total gasoline refining, giving some idea as to our tiny market. And any improvements are very expensive, meaning they won't sell anyway.

So we need better education for students, which means better education for instructors. They need to understand magneto theory and failure management. They need to understand carb ice and its recognition and management. Alternators and electrical systems. Lots of stuff. And owners need to understand the peculiar needs of their airplanes and engines, and figure that into the cost of ownership. Too many buy as much airplane as they can afford, and are left with nothing to cover the cost of fixing the stuff that has often been ignored by the previous owners and has now decided to show up. These are old machines, folks, operating on old technology just like Grandpa's '59 Buick. Even your brand-new airplane, behind all that fancy glass panel stuff, has a lot of old technology like cam-operated diaphragm-type fuel pumps, magnetos, continuous-flow mechanical fuel injection, cables and pulleys and unsealed bearings of many types. Years and hours attack all of it.
 
Mopauly said:
Here's the ATC audio; I pulled it from LiveATC and edited out the other traffic. Conversation starts right after they asked if I was declaring.

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I have flown 80 Alpha several times!!! Wow! I'm so glad you're OK...great job staying calm and just flying the airplane.
 
Hey Paul, I saw 80A was back on the ramp yesterday. Did they let you know what they found?

-Jim
 
buzzard86 said:
Hey Paul, I saw 80A was back on the ramp yesterday. Did they let you know what they found?

-Jim
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Last I had heard was the right magneto was replaced, I haven't flown it since; I usually fly the Arrow as it helps me move more animals faster, only went to 80A that day as the Arrow was booked.
 
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