What happens when a MAG actually fails on your run up? Find out what happens to the airplane, what it sounds like and talk to a mechanic about when and why mags fail.
Just happened to me today! Went to TH-cam to try and see what others experienced. I felt it go out in flight. Landed, did a run up after fueling, and got the No drop, then complete dead on the other mag. Identical to you. This is so helpful. Time to overhaul the mags!
So the best thing that can happen is having the Magneto on? Its like not removing the spark plug from a car before driving somewhere with the engine on. So according to this www.aopa.org/news-and-media/all-news/2002/january/flight-training-magazine/the-magneto-check#:~:text=Think%20about%20it%20-%20if%20you,that%20prevents%20it%20from%20working. It would certainly seem that having a working magneto is one of the most important things in any helicopter or aircraft in case the alternator fails. I only say this because in another video I watched 4 people climbed into what appears to be a Robinson r22 helicopter which by itself weighs less than 1500 lbs and loaded the weight of 4 people and several semi auto assault rifles so probably added an additional 900 lbs to their ride and climbed up to maybe 150 feet or much less like 75 feet before the RPMs died and they used the auto rotation feature to glide down to the ground landing poorly as not pointing the nose of the helicopter up to take full advantage of the auto rotation but regardless landing fairly smoothly aside from a few bumps and bruises and the helicopter even looked intact (mostly.) Everyone agreed it was a heroic landing including me. But when I pointed out I believed the error was overloading the helicopters weight limit especially with munitions strapped with rifles and ammo etc probably creating some stress on the engine I was called out by several commentators that apparently I am "misinformed about how aircraft work" especially when I challenged the idea that in flight school 50% of the lessons learned in obtaining a PPL or CFI involve just learning to land the airplane. Now I have been called out in a comments thread as not liking guns because I question the flight regulations involving the pilot himself being armed to the teeth while flying (regardless of the amount of times I have gone out shooting rifles) and my idea of flight school is misinformed and my idea of a magneto not being switched off being what actually caused the helicopter malfunction the helicopter dropped almost like a brick to the ground minus some sloppy work with the autorotation at the last minute. Lol not trying to drag my argument from another videos comments section into this video. I am just always amazed at pilots who believe in creating excuses for their mistakes instead of admitting what they do wrong. I applaud any safe landing previously about to turn fatal and commend anyone continuing to live for a really long time. If 4 people hopped on the back of a motorbike with gear loaded on and the bike takes off and falls over after some few hundred feet I imagine I would not say "the bike fell over because I forgot to take the spark plug out before riding out onto the road causing a malfunction in the engine and the bike to fall over." I know not everyone gets their PPL to get an additional 1500 hours of flight time then to fly for the FAA but I still think pilots who make the same mistakes over and over and over should have their license pulled.
I do a Mag's check before shut down as well as on Run Up, so you might have picked it up then. As I am Ex-RAF one of the things that I find funny about most GA pilots, is they don't do a walk round After Flight only do a Pre Flight, I like doing a After Flight as that way I know my plane is still in one piece or I know I have to fix something before next flight, and the Pre Flight just makes sure the Mice have not got in and made a nest or drunk all the engine oil.
You caught yourself falling into a checklist trap. You called out that there was a good drop as you were performing the test and before you had the results. Good job. You might think about changing up your checklist routine. Try to find a method that forces you to process the info before calling out the answer.
This same thing happened to me on a remote location. I had no choice but to leave the airplane there, rent a car and drive 5 hours back home. 10 days later I came back to pick up my airplane. Thankfully there was a mechanic in the field that helped me out big time.
Maybe goes without saying, but the no RPM drop on the left mag check because the left mag was the only thing running the engine on 'both' as well, so there would have been no change in spark between 'both' and 'left.'
Had a mag on a C172 go south, but not this bad. Usually fouled plugs. Trick was to lean it out and see if the fouling could be burned off. When that didn't do the trick, taxi back to parking and call it a day. Yup, this is why we preflight, for the 1 in 1000 times when stuff doesn't work.
The mag may have failed during flight to your destination. Naturally you parked and shut the engine down then. If you did a mag check before shutdown, you may have discovered the bad mag then. But that is not a normal procedure, so it doesn't show up till the next day when you prepare to depart. Cheers from Winnipeg.
Peter Toth That’s what I figured happened because during the flight the engine just started running slightly rough so piecing it altogether that’s exactly what happened thanks for watching!
Similar thing just happened to me a few weeks ago except in my case I had an RPM drop. The right mag dropped like normal and the left mag sputtered to a near stop. It turns out that the left mag's break point was not breaking enough causing a loss of voltage going to the spark plugs.
@over 50: I would strongly recommend installing a graphic engine monitor for safety and the longevity of your engine. It was one of the first things I added to my panel when I bought my Cardinal.
Magnetos differ from the ignition on cars in one major way, magnetos produce their own electricity to supply the spark to the spark plugs. In this way, there are two independent electricity sources to keep your engine running, independent even from the battery and electrical system of the aircraft. Its actually similar to a push lawn mower in that respect. Once the engine is spinning on the lawn mower, it generates its own electricity to supply the spark plug. Same with aircraft engines, except there is double redundancy, hence two mags.
Many years ago, I was returning to base when my engine tone changed. Says I to myself: "I'll just do a mag check so I can give some pertinent info to the 'chappies' on the ground". Then reached up and turned off the operating magneto... The silence was deafening. PS I remembered to place the throttle to idle before switching to 'on'...) (;>0)
Yep, I had a mag fail “once” luckily it was just a fun trip, not going anywhere special or on a schedule..... And one flat tire, luckily on that one too, it happened after taxiing to the run up area....
I experienced a dual mag failure on final while training for PPL, didn’t realize it until after landing when the engine was out and couldn’t taxi to ramp!
The odds of two mags failing at the same time is astronomical. Now if you don't do a mag check ever... then you could have been flying on one mag for a year before the second fails. Then you would actually have a two mag failure. Or if the mechanic had miss wired the mag switch and the switch never allowed you to shut down a mag. The test for this is to go to OFF and make sure the engine shuts down.
The reason you don't get a mag drop on one mag is because the engine is only running on one mag and that's the one it's running on. It'll be running slightly rougher than usual though because each cylinder will only be getting one spark instead of two. Naturally when you move off that mag onto the one that's failed the engine will cut . You did the right thing - that's why we do mag checks in our pre-flight. Two mags give you the essential safety factor that you need to stay in the air if one fails. If you are flying on only one mag and that fails it can ruin your whole day.
I had a mag failure once. It worked great on the ground but on climbout it stumbled a little. I circled around and landed. It worked fine at 1,700 RPM but not at full power. I think the bearing had failed as I recall.
It is amazing how our understanding of various aircraft components and systems increases after we accumulate experience with different failures. You will notice your Cardinal’s engine has 2 spark plugs per cylinder verses the single spark plug in your gas lawn mower. For safety your Cardinal’s piston engine was designed with redundancy in the ignition system; two magnetos, two sets of ignition leads lead to two spark plugs in EACH cylinder. If one component fails in your ignition system you aren’t automatically forced to look for someplace to land. With both spark plugs firing at the right time you get a more efficient burn in your cylinder. When only one spark operates you get a less efficient burn in your cylinder producing less power that shows up as a drop in RPM. But you can shove the throttle in further, add more fuel and bring the RPM up. That’s why you showed no drop during your mag check. Apparently you only had one ignition system operating. With the one operating system you brought the RPM up to 1,700, then “shut down” the failed mag/ignition system which had ZERO effect on the RPM because it wasn’t working in the first place. On the other hand when you checked the other side and shut down the only operating ignition system SURPRISE things got real quiet….. Your first clue of a failed magneto during the run up was when you did not see an RPM drop when you did your “mag check” (If you checked the operating MAG first). Decades ago I was flying Cessna 206s in a remote region of the world (jungle). We had a STC (supplemental type certificate) for an emergency secondary fuel system to back up the fuel injection system that came with the Continental engines we operated with. The emergency fuel system introduced fuel into the induction system bypassing the fuel injection system entirely. It worked well and would get you home in a case where the fuel injection system failed. It was another level of redundancy. Somewhere along this journey I heard this: “Experience is a difficult instructor, first it administers the test then it teaches the lesson”.
I had this happen to me a day ago and it happened in Cruz flight the right magneto failed. The gears inside the magneto striped out good thing I was able to run it on the left magneto and landed within 10 minutes.
Cool vid. Was just there the other day. No mag probs then. Now that I’m back home the right one is is starting to go… Not over the water is always preferred! If you don’t mind the asking, what was ballpark price?
I do an inflight mag check on long cross countries, when I go back and look at the JPI data you can always see when you did it based upon the RPM drop. It gives me peace of mind that I’m not a mag failure away from an “engine out” glider experience. So my advice is add to your wish list a JPI-830 or if you can afford it a 930 and get rid of your primary fuel/oil gauges. I would not fly my family in a 40 + year old plane without a real engine analyzer that’s just part of my personal minimums. I’m thinking of upgrading to a SureFly electronic ignition. It blows me away that we are just now getting rid of vacuum instruments and we are even slower to adopt electronic ignitions (not sure when the last car with points was sold in the US but it was a while ago). All my friends that have made the switch say that there is a fuel economy payback. To me that’s a side benefit to be considered after risk reduction. Love your channel!
Why do an inflight mag check that could involve your engine cutting out? If the engine is running a bit rough, you land, you don't do a mag check in the air. If the engine doesn't restart you will be in trouble when you might have landed safely with just a rough engine. IMO inflight mag check = very bad procedure.
@@battz99 sorry for the lack of clarity. I’m not suggesting you do it if you already have engine roughness I’d suggest getting on the ground quickly or at least in the pattern then if you have roughness check mixture, fuel source, carb ice, etc. my point was to see a potential mag problem before it’s obvious. a mag check in cruise can give you data that can show a failing mag in post flight JPI data analysis. Hope that clarifies.
@@johnquimby3079 Hi John. I'm a big fan of letting sleeping dogs lie. If P's, T's, RPM and airspeed are all good and stable I'd leave my mags well enough alone and do a mag check at shutdown. If a mag is on the way to failing in flight to the point it's becoming noticeable it will show itself in other ways eg you'll notice that your revs to maintain airspeed are slowly increasing. My first reaction would then be to check for carb icing. If that doesn't work I'd probably immediately suspect a mag problem and look for an airfield. I've had a mag go on me that did exactly that - OK the previous flight but then airspeed and rpm all wrong next time out. I can tell you, I couldn't get down onto a runway quick enough 😀
@@battz99 We could solve the debate and upgrade to electronic ignitions and eliminate technology invented in 1897! I agree with a prior posted comment - post flight mag check is a best practice. I just put in a new breaker and pre-wired for a Sure-Fly in 2021.
I hear way too many stories of unexpected problems cominh up. Not comforting! Wasnt it said you just had an anual? What good are those if they dont catch the problem.
Curious to know, what sound would it make if you had 1 or both mags fail while IN flight ( up in the air )? And would the engine cut out in the air? No sound at all?
Jeremy Griffith It’s what the mechanic suggested and he said he can have the new one here in a day so I just went with that but what I was thinking of was having him replace the other one while it’s there I’ll talk to him tomorrow and see what he says about that
Just happened to me today! Went to TH-cam to try and see what others experienced. I felt it go out in flight. Landed, did a run up after fueling, and got the No drop, then complete dead on the other mag. Identical to you. This is so helpful. Time to overhaul the mags!
Bad day, but that is why we have checklists! Thanks for sharing with us so those of us still learning can watch this before we see it firsthand.
This is gold. There isn't as much training about decesion making about when things are moderately wrong.
Well worth sharing. This is exactly why engines have two mags.
So the best thing that can happen is having the Magneto on? Its like not removing the spark plug from a car before driving somewhere with the engine on. So according to this
www.aopa.org/news-and-media/all-news/2002/january/flight-training-magazine/the-magneto-check#:~:text=Think%20about%20it%20-%20if%20you,that%20prevents%20it%20from%20working.
It would certainly seem that having a working magneto is one of the most important things in any helicopter or aircraft in case the alternator fails.
I only say this because in another video I watched 4 people climbed into what appears to be a Robinson r22 helicopter which by itself weighs less than 1500 lbs and loaded the weight of 4 people and several semi auto assault rifles so probably added an additional 900 lbs to their ride and climbed up to maybe 150 feet or much less like 75 feet before the RPMs died and they used the auto rotation feature to glide down to the ground landing poorly as not pointing the nose of the helicopter up to take full advantage of the auto rotation but regardless landing fairly smoothly aside from a few bumps and bruises and the helicopter even looked intact (mostly.)
Everyone agreed it was a heroic landing including me. But when I pointed out I believed the error was overloading the helicopters weight limit especially with munitions strapped with rifles and ammo etc probably creating some stress on the engine I was called out by several commentators that apparently I am "misinformed about how aircraft work" especially when I challenged the idea that in flight school 50% of the lessons learned in obtaining a PPL or CFI involve just learning to land the airplane.
Now I have been called out in a comments thread as not liking guns because I question the flight regulations involving the pilot himself being armed to the teeth while flying (regardless of the amount of times I have gone out shooting rifles) and my idea of flight school is misinformed and my idea of a magneto not being switched off being what actually caused the helicopter malfunction the helicopter dropped almost like a brick to the ground minus some sloppy work with the autorotation at the last minute.
Lol not trying to drag my argument from another videos comments section into this video. I am just always amazed at pilots who believe in creating excuses for their mistakes instead of admitting what they do wrong. I applaud any safe landing previously about to turn fatal and commend anyone continuing to live for a really long time.
If 4 people hopped on the back of a motorbike with gear loaded on and the bike takes off and falls over after some few hundred feet I imagine I would not say "the bike fell over because I forgot to take the spark plug out before riding out onto the road causing a malfunction in the engine and the bike to fall over."
I know not everyone gets their PPL to get an additional 1500 hours of flight time then to fly for the FAA but I still think pilots who make the same mistakes over and over and over should have their license pulled.
I do a Mag's check before shut down as well as on Run Up, so you might have picked it up then.
As I am Ex-RAF one of the things that I find funny about most GA pilots, is they don't do a walk round After Flight only do a Pre Flight, I like doing a After Flight as that way I know my plane is still in one piece or I know I have to fix something before next flight, and the Pre Flight just makes sure the Mice have not got in and made a nest or drunk all the engine oil.
Thanks for sharing. I’m just in the first stages of learning so seeing this is gold!
You caught yourself falling into a checklist trap. You called out that there was a good drop as you were performing the test and before you had the results. Good job.
You might think about changing up your checklist routine. Try to find a method that forces you to process the info before calling out the answer.
charles streeter absolutely - I am changing my checklist!
This same thing happened to me on a remote location. I had no choice but to leave the airplane there, rent a car and drive 5 hours back home. 10 days later I came back to pick up my airplane. Thankfully there was a mechanic in the field that helped me out big time.
Maybe goes without saying, but the no RPM drop on the left mag check because the left mag was the only thing running the engine on 'both' as well, so there would have been no change in spark between 'both' and 'left.'
Had a mag on a C172 go south, but not this bad. Usually fouled plugs. Trick was to lean it out and see if the fouling could be burned off. When that didn't do the trick, taxi back to parking and call it a day. Yup, this is why we preflight, for the 1 in 1000 times when stuff doesn't work.
The mag may have failed during flight to your destination. Naturally you parked and shut the engine down then. If you did a mag check before shutdown, you may have discovered the bad mag then. But that is not a normal procedure, so it doesn't show up till the next day when you prepare to depart. Cheers from Winnipeg.
Peter Toth That’s what I figured happened because during the flight the engine just started running slightly rough so piecing it altogether that’s exactly what happened thanks for watching!
Similar thing just happened to me a few weeks ago except in my case I had an RPM drop. The right mag dropped like normal and the left mag sputtered to a near stop. It turns out that the left mag's break point was not breaking enough causing a loss of voltage going to the spark plugs.
@over 50: I would strongly recommend installing a graphic engine monitor for safety and the longevity of your engine. It was one of the first things I added to my panel when I bought my Cardinal.
I totally want one !
Magnetos differ from the ignition on cars in one major way, magnetos produce their own electricity to supply the spark to the spark plugs. In this way, there are two independent electricity sources to keep your engine running, independent even from the battery and electrical system of the aircraft. Its actually similar to a push lawn mower in that respect. Once the engine is spinning on the lawn mower, it generates its own electricity to supply the spark plug. Same with aircraft engines, except there is double redundancy, hence two mags.
Many years ago, I was returning to base when my engine tone changed.
Says I to myself: "I'll just do a mag check so I can give some pertinent info to the 'chappies' on the ground". Then reached up and turned off the operating magneto...
The silence was deafening.
PS I remembered to place the throttle to idle before switching to 'on'...)
(;>0)
Yep, I had a mag fail “once” luckily it was just a fun trip, not going anywhere special or on a schedule.....
And one flat tire, luckily on that one too, it happened after taxiing to the run up area....
This is why u do preflight while parked at FBO. It’s not worth what you save on the hobbs meter
I experienced a dual mag failure on final while training for PPL, didn’t realize it until after landing when the engine was out and couldn’t taxi to ramp!
The odds of two mags failing at the same time is astronomical. Now if you don't do a mag check ever... then you could have been flying on one mag for a year before the second fails. Then you would actually have a two mag failure. Or if the mechanic had miss wired the mag switch and the switch never allowed you to shut down a mag. The test for this is to go to OFF and make sure the engine shuts down.
The reason you don't get a mag drop on one mag is because the engine is only running on one mag and that's the one it's running on. It'll be running slightly rougher than usual though because each cylinder will only be getting one spark instead of two. Naturally when you move off that mag onto the one that's failed the engine will cut . You did the right thing - that's why we do mag checks in our pre-flight. Two mags give you the essential safety factor that you need to stay in the air if one fails. If you are flying on only one mag and that fails it can ruin your whole day.
I had a mag failure once. It worked great on the ground but on climbout it stumbled a little. I circled around and landed. It worked fine at 1,700 RPM but not at full power. I think the bearing had failed as I recall.
Great teaching video sir. Thank you
It is amazing how our understanding of various aircraft components and systems increases after we accumulate experience with different failures. You will notice your Cardinal’s engine has 2 spark plugs per cylinder verses the single spark plug in your gas lawn mower. For safety your Cardinal’s piston engine was
designed with redundancy in the ignition system; two magnetos, two sets of ignition leads lead to two spark plugs in EACH cylinder. If one component fails in your ignition system you aren’t automatically
forced to look for someplace to land. With both spark plugs firing at the right time you get a more efficient burn in your cylinder. When only one spark operates you get a less efficient burn in your cylinder producing less power that shows up as a drop in RPM. But you can shove the throttle in further, add more fuel and bring the RPM up. That’s why you showed no drop during your mag check. Apparently you only had one ignition system operating. With the one operating system you brought the RPM up to 1,700, then “shut down” the failed mag/ignition system which had ZERO effect on the RPM because it wasn’t working in the first place. On the other hand when you checked the other side and shut down the only operating ignition system SURPRISE things got real quiet….. Your first clue of a failed magneto during the run up was when you did not see an RPM drop when you did your “mag check”
(If you checked the operating MAG first).
Decades ago I was flying Cessna 206s in a remote region of the world (jungle). We had a STC (supplemental type certificate) for an emergency secondary fuel system to back up the fuel injection system that came with the Continental engines we operated with. The emergency fuel system introduced fuel into the induction system bypassing the fuel injection system entirely. It worked well and would get you home in a case where the fuel injection system failed. It was another level of redundancy.
Somewhere along this journey I heard this: “Experience is a difficult instructor, first it administers the test then it teaches the lesson”.
I had this happen to me a day ago and it happened in Cruz flight the right magneto failed. The gears inside the magneto striped out good thing I was able to run it on the left magneto and landed within 10 minutes.
Cool vid. Was just there the other day. No mag probs then. Now that I’m back home the right one is is starting to go… Not over the water is always preferred!
If you don’t mind the asking, what was ballpark price?
I think it was around 350…. Thanks for watching!
The joys of aircraft ownership.
I do an inflight mag check on long cross countries, when I go back and look at the JPI data you can always see when you did it based upon the RPM drop. It gives me peace of mind that I’m not a mag failure away from an “engine out” glider experience. So my advice is add to your wish list a JPI-830 or if you can afford it a 930 and get rid of your primary fuel/oil gauges. I would not fly my family in a 40 + year old plane without a real engine analyzer that’s just part of my personal minimums. I’m thinking of upgrading to a SureFly electronic ignition. It blows me away that we are just now getting rid of vacuum instruments and we are even slower to adopt electronic ignitions (not sure when the last car with points was sold in the US but it was a while ago). All my friends that have made the switch say that there is a fuel economy payback. To me that’s a side benefit to be considered after risk reduction. Love your channel!
Why do an inflight mag check that could involve your engine cutting out? If the engine is running a bit rough, you land, you don't do a mag check in the air. If the engine doesn't restart you will be in trouble when you might have landed safely with just a rough engine. IMO inflight mag check = very bad procedure.
@@battz99 sorry for the lack of clarity. I’m not suggesting you do it if you already have engine roughness I’d suggest getting on the ground quickly or at least in the pattern then if you have roughness check mixture, fuel source, carb ice, etc. my point was to see a potential mag problem before it’s obvious. a mag check in cruise can give you data that can show a failing mag in post flight JPI data analysis. Hope that clarifies.
@@johnquimby3079 Hi John. I'm a big fan of letting sleeping dogs lie. If P's, T's, RPM and airspeed are all good and stable I'd leave my mags well enough alone and do a mag check at shutdown. If a mag is on the way to failing in flight to the point it's becoming noticeable it will show itself in other ways eg you'll notice that your revs to maintain airspeed are slowly increasing. My first reaction would then be to check for carb icing. If that doesn't work I'd probably immediately suspect a mag problem and look for an airfield. I've had a mag go on me that did exactly that - OK the previous flight but then airspeed and rpm all wrong next time out. I can tell you, I couldn't get down onto a runway quick enough 😀
@@battz99 We could solve the debate and upgrade to electronic ignitions and eliminate technology invented in 1897! I agree with a prior posted comment - post flight mag check is a best practice. I just put in a new breaker and pre-wired for a Sure-Fly in 2021.
@@johnquimby3079 Good call
I hear way too many stories of unexpected problems cominh up. Not comforting!
Wasnt it said you just had an anual?
What good are those if they dont catch the problem.
Better down on the ground, than up there in the air.
Thank you for sharing this video! I do have one question...why do you keep the mixture a "little lean" on the runup instead of full rich? Tnx.
Curious to know, what sound would it make if you had 1 or both mags fail while IN flight ( up in the air )? And would the engine cut out in the air? No sound at all?
One mag out the engine may run rough - both the engine would cut out - I 🤔 think .... thanks for watching!
Took 8 times of trying it to figure out it was a bad mag. SMH
I just had the exact same thing happen on my 1971 Cardinal. What was your thought process on swapping out the magneto vs overhaul?
Jeremy Griffith It’s what the mechanic suggested and he said he can have the new one here in a day so I just went with that but what I was thinking of was having him replace the other one while it’s there I’ll talk to him tomorrow and see what he says about that
I flew with a friend in his c3 thats all there is one mag
What did it cost to replace the mag?
Randy McCarter 750
What was 'Plan B'? Hotel? Rent a car? Rent another plane?
....surprised it took so long to convince y'all....it wasn't fuel, it was spark.
Am I allowed to say 1st comment or is that illeagal?