total electrical failure this morning

[Lachlan]

Anyone have any recommendations on a good but not too expensive model to purchase?

iCom A24 is a great little handheld. Works quite well in the air and on the ground (for getting ATIS, listening to Ground, local traffic, etc) and it has a passable VOR with CDI. I wouldn't want to use that feature for navigation exclusively, but it's there and it works in case of catastrophic iPad failure. HA.

 

[Sundancer]

The longer I fly, the less I carry. . .I probably should get another hand-held to replace my dead iCom.

 

[WannFly]

I have an ancient one from Sportys. They're about 200 or just under for the cheapest ones. I figured it was good security to have for the price of about 2hrs plane rental. I've seen people posting them for sale locally too for less

PS- I think that's my favorite thing in the Cirrus is the dual alternator and 2 buses, one alt is gear driven the other belt

Modern 172 s have a backup battery, post like these makes me want to install one in my piper...

Sent from my SM-G935V using Tapatalk

 

[Dan Thomas]

Agreed...the low voltage light will "fail" at some point well after the alternator fails because the battery is no longer being charged. But it's designed to illuminate in the event of an alternator failure. If it didn't illuminate at all, there are other issues with the airplane that should be addressed.

Also true on "charging". I was referring to an ammeter that has both "+" and "-" sides. It's tied to the battery side of the system so it more directly shows amperage in or out of the battery rather than alternator output.

So...any explanation of the "main breaker" yet?

That low voltage light won't illuminate in two of the most common modes of alternator failure: the worn-out field brushes or the broken field wire. It won't detect a broken belt, either. All it senses is a loss of voltage at the stator terminal on the regulator, which is fed by the alternator side of the master, and the overvolt sensor which is in series between the switch and stator terminal. The light is nearly useless.

That light is the idiot light in a car. The car's alternator's stator terminal feeds that regulator's stator terminal when the alternator starts turning, and turns on the regulator to feed the field. (At least that's how they used to do it; the regulator is built into the alternator now.)

No "main breaker" in any light airplane I've ever maintained. The only means of cutting off the battery from the system is the battery contactor. No breaker or fuse. The reason is obvious: you'd have to have that battery cable come into the cabin to a big breaker on the panel, meaning a long, electrically unprotected length of cable that could not be shut off if it shorted against something. Big fire. That's why we have a short length of cable to a very close contactor controlled from the cockpit by a switch that grounds its cold side, avoiding any unloaded and unprotected wire. If it shorts it just turns the master on.

 

[GlennAB1]

Everyone praised Sully for landing in the river and saving lives. Looked at from a different point of view, look at all the luggage he lost....

Sully rehearsed that exact river landing scenario many times in his head before actually doing it. How is that being a hero? AND, He did make one big mistake that could have cost him the title.

 

[TommyG]

Why were you so focused on fuel? You know how much you had when you took off, if you had full tanks you know you have a solid 4 hours to fly. Fuel gauges are generally useless anyway. But fly the plane and troubleshoot. Focus on the problem at hand and whatever potential problems may arise. Electric problems first thing is check the breakers and master. If the same breaker pops, leave it alone. If it is a possible alternator problem, reduce load as much as possible. I had an alternator years back flying from BID to FRG! Ultimately shut the master switch off until just outside of FRG, put it back on and contacted tower.

 

[MauleSkinner]

Modern 172 s have a backup battery, post like these makes me want to install one in my piper...

I had an aux power output jack on the radio bus of my Maule. Great thing about wires is, electricity can either way...I could plug a battery into that and power some avionics if the ship's battery & generator died.

 

[jspilot]

Why were you so focused on fuel? You know how much you had when you took off, if you had full tanks you know you have a solid 4 hours to fly. Fuel gauges are generally useless anyway. But fly the plane and troubleshoot. Focus on the problem at hand and whatever potential problems may arise. Electric problems first thing is check the breakers and master. If the same breaker pops, leave it alone. If it is a possible alternator problem, reduce load as much as possible. I had an alternator years back flying from BID to FRG! Ultimately shut the master switch off until just outside of FRG, put it back on and contacted tower.

I knew the gauges had to be wrong because of exactly what you said-- the tanks were full when I took off. That being said, we've all read stories about guys who said "the gauge is wrong" or "the instrument is wrong" only to find out the gauge and instrument was right. Honestly that's the thought I had. I was 95% certain the gauges were wrong but if that 5% chance they were right existed, I wanted to be in a safe position just in case.

 

[rocketflyer84]

Hindsight is always 20/20 in these situations. You got the plane and passenger back safely and that's all that matters. Sounds like you did a nice job.

A handheld radio is a good addition to the flight bag. They're nowhere near as good as the radios in the plane, but it's certainly better than nothing. I carry a radio and the adapter plug to put my headset into it in my flight bag.

Had an alternator go once but was just after departure and was able to land before the radios died. Gave Tower a heads up so they immediately cleared me to land and told me to continue in even if we lost radio contact.

PS I hope the rental outfit didn't charge you for the flight!

 

[flyingron]

If you're going to get a handheld, get one that will accept an Alkaline AA cell battery pack and keep that and some batteries (I'd avoid leaving the batteries in the pack in case of leakage) with you at all time. The rechargeables have the bad habit of being dead when you need them (the aforementioned NORDO approach into IAD was done with a dead KX99).

My old radio guy just looped the antenna cable for my com to the bottom of the panel and put a BNC male/female combo. If I had to, I could reach up and disconnect my panel radios and plug in the handheld. Thing was that he didn't tell me he did that. A found it a year later when I was up under the panel looking for something else.

Still, more often than not in terminal areas, the rubber ducky works fine to get you down.

 

[SoonerAviator]

A little late, but I'll give my .02. You did well by getting yourself back to the airport with no bent metal or FAA repercussions. Kudos on that. However, you keep reiterating that your first choice of action for any failures is to get back on the ground immediately and let the mechanic sort it out. I believe that to be a bit short-sighted. We have the emergency checklists and POH checklists for a reason, and you should revert to those first as long as there isn't a more pressing emergency (like an in-flight fire). When landing - use the checklist. When the engine stops - use the checklist. When you lose electrical power - use the checklist. They exist for the sole purpose of being the primary quick reference material for normal and abnormal operations. Again, you did well by returning home and not pranging metal in the process, but the important thing to take away was that you should have more knowledge on how to do it better if it should occur again. You could have shed enough load/reset the main breakers to at least have enough power to communicate the issue with ATC get the 7600 ping out there, which could have assisted in getting you back home with less anxiety. If your instruments came back to life, you would have seen the fuel gauges return to normal, which would have calmed your fears about running out of fuel. In the end, you're still a pilot, with a bit more experience to add to your bag.

 

[Tantalum]

...can I just say I HATE the stupid little "voltage" light on the old Skyhawks... what a useless light. The plane I usually rent has a digital voltage meter which I love, but some of the other club planes just have the ammeter (which seems to always ready zero) and the light couldn't be less helpful. I had the light come on recently towards the tail end of a climb as I leveled off... then it went out and was fine the rest of the way. When I read up on the light post flight I read that it could pretty much mean anything from high voltage, to low voltage, to the alternator being off, etc.

 

[Dan Thomas]

...can I just say I HATE the stupid little "voltage" light on the old Skyhawks... what a useless light. The plane I usually rent has a digital voltage meter which I love, but some of the other club planes just have the ammeter (which seems to always ready zero) and the light couldn't be less helpful. I had the light come on recently towards the tail end of a climb as I leveled off... then it went out and was fine the rest of the way. When I read up on the light post flight I read that it could pretty much mean anything from high voltage, to low voltage, to the alternator being off, etc.

That light is the same light, wired the same way, in both "high voltage" and "low voltage" systems. If the overvoltage sensor detects a voltage above a defined maximum, the sensor cuts off the flow from the alternator switch to the regulator, turning it off and triggering that light. The alternator stops generating,which of course means that system voltage is falling. It depends on what year the airplane was built as to what they called the light. The only differences are the placard and POH.

If you turn on just the "Bat" side of the master, the light should come on. Turn on the "Alt" side and it should go out. That's about all it's indicating. It's not the same as the old "Gen" lights in generator-powered airplanes, where the light did indeed detect a generator failure. It would usually light at low RPM, too, since the generators weren't too good at keeping up unless they were spinning madly.

 

[Tantalum]

If the overvoltage sensor detects a voltage above a defined maximum

And that makes sense, since it was fine on the ground and run up and fine later in the flight, but came on after about 10-15 minutes of a day climb... makes sense that with a light load on the system and the engine at 2,700 RPM the battery would top off and alternator would kick off

Still pretty stupid though. I much prefer the reassuring 13.7 (or thereabouts) on the voltage gauge

That light really won't be much help to someone to be honest as far as being preventative... let's say the OP had noticed that the light was illuminated before his radios died. For all he knew it could have just meant the alternator was off after a full power climb and the batt was topped off. It's like if your gas light on your car illuminated at either a full tank or an empty tank.. I guess it's just enough to keep you on your edge until either the light goes out or you lose your batt

 

[MauleSkinner]

And that makes sense, since it was fine on the ground and run up and fine later in the flight, but came on after about 10-15 minutes of a day climb... makes sense that with a light load on the system and the engine at 2,700 RPM the battery would top off and alternator would kick off

Still pretty stupid though. I much prefer the reassuring 13.7 (or thereabouts) on the voltage gauge

That light really won't be much help to someone to be honest as far as being preventative... let's say the OP had noticed that the light was illuminated before his radios died. For all he knew it could have just meant the alternator was off after a full power climb and the batt was topped off. It's like if your gas light on your car illuminated at either a full tank or an empty tank.. I guess it's just enough to keep you on your edge until either the light goes out or you lose your batt

You're misunderstanding the light...if it illuminates, something is wrong. Whichever of the problems it happens to be, high voltage, low voltage, or offline, the checklist should address it.

After letting the smoke out of the wires trying to follow that checklist, however, I was told that when it says Master Switch OFF then ON, it really means only the alternator side. Leaving the battery on provides shock absorption for voltage spikes.

 

[Tantalum]

if it illuminates, something is wrong. Whichever of the problems it happens to be, high voltage, low voltage, or offline, the checklist should address it.

Right, and my post was maybe a bit tongue in cheek... but that's still kind of a pathetic light in my opinion. Maybe when these planes were new it was the simplest way to provide a warning light that could address an array of problems, but I still prefer an actual indication of the voltage to the battery, or at least an ammeter that didn't seem pegged on zero. The Piper I fly seems to have a more indicative ammeter, you can see it "pick up the load" (so to speak) when you hit the pitot heat, etc. I've read on other forums that those voltage lights on the old Skyhawks don't get much love. I hate to sound like a Cirrus fanboy (esp because I don't consider myself one) but seeing the two buses, the loads, etc. right there is very convenient. Oh well... 2000s technology I guess vs 1950s

 

[Clip4]

I was waiting for this type of post. Can always count on no it alls chiming in.

My CFI covered all this with me and that's what said to me that it was an electrical failure. He also taught me to squawk 7600 whenever the radios go out. That's what I did!

Slowing the plane down was not a problem as evidence by the fact that we touched down and got off the runway in about 1/4 of the usable space!

I do not remember getting taught about cycling the master hence why I did not do that!

As explained in my post, I was not totally confident what I was dealing with until the flaps would not extend and at that point I knew it was electrical failure. Would it have made sense to load shed on a 1/2 mile final with a plane on the runway in front of me, and me being terrified I was going to get hit by another plane in the pattern, maybe but I just flew the plane down.

You said you are a low time guy so I'll assume maybe you have not yet delt with a situation in which you are concerned about lots of things at once. My thought process was get the plane on the ground safely and trouble shoot at the tie downs! I don't blame myself for that!

Being 90% sure it's an electrical failure as I was still leaves that 10% that it is not. I'm not, nor will not, put my life or my passengers life in my ability to trouble shoot something while airborn. Fixes should occur on the ground not in the air in my opinion and I'm fine with how I handled this.

I really don't want this thread to turn into a "I know better than you" type thread. So far it has not and I only shared so that we can all share experiences with each other with a similar event so we can all learn from it!

You returned home and all is well, but you should get out the checklist when you have an abnormal condition. You may have temporarily resolved the problem. The checklist also would have told you to land as soon as practical rather than returning to departure. Besides the radios and fuel gauges, you also lost temperature and probably the oil pressure gauge. At that point, the aircraft is unairworthy.

 

[jspilot]

You returned home and all is well, but you should get out the checklist when you have an abnormal condition. You may have temporarily resolved the problem. The checklist also would have told you to land as soon as practical rather than returning to departure. Besides the radios and fuel gauges, you also lost temperature and probably the oil pressure gauge. At that point, the aircraft is unairworthy.

You know what is interesting is I distinctly remember the oil pressure and oil temp gauges were still working fine which is why I felt confident the engine was still working fine. It's really weird how and which things failed in this situation. I'm very eager to speak to the mechanic again to see what they discovered and what steps they took to remedy the issue!

With regards to the low voltage light, I can tell you for sure it never came on and the amp meter never showed a discharge. I checked both thinking they should be registering a discharge or be illuminated and they were not. Again, this is why I was getting confused about what was actually going on since the indications I was expecting to see did not match what I thought was happening and this created that urgency to land I've described several times.

I do believe this adds another layer to the conversation though and that is, why do single engine airplanes have indicators that are often misleading to the pilot or essentially useless? Seems like they are not even worth having as some have said. I would have liked to have had a voltage indicator directly connected to the battery or something like that so I could have seen exactly how much voltage the battery was producing! If that would have been on board and I could have seen it reading 2 amps or 0 or whatever I would have had an easy way to know exactly what was happening!

 

[Dan Thomas]

And that makes sense, since it was fine on the ground and run up and fine later in the flight, but came on after about 10-15 minutes of a day climb... makes sense that with a light load on the system and the engine at 2,700 RPM the battery would top off and alternator would kick off

The alternator has a rotor that has a big coil of copper wire around it. The engine spins that rotor. It's the alternator's "field." The copper wire is fed current from the voltage regulator via two carbon "brushes" that are just blocks of graphite that conduct the field current from the stationary alternator case to the spinning rotor's two copper slip rings, which then feed it through that copper coil. We get an electromagnetic field that way, and spinning that field through the stationary coils of the alternator's stator causes electrons to flow in the stator. That current is rapidly alternating between positive and negative (why we call it an alternator; it makes AC) but we need direct current (DC) for the airplane, so we feed that AC through six diodes to sort it out into DC. That's the output.

There are three things that determine the output of an alternator. One is the number of turns of copper wire in the field and the stator. We can't change those too easily. Another is the strength of the electromagnetic field made by the rotating field. The third is the speed at which the rotor turns, which changes with engine RPM. It's rather inconvenient to try to control the alternator's output by changing the throttle setting, so we change the field's strength instead by varying the amount of current we feed it.

The voltage regulator controls the alternator. When the system is below the set voltage level, the regulator feeds more field current into the alternator's rotor, strengthening the magnetic field, which makes the stator produce more current, which, if we pay attention to Ohm's Law, will raise the voltage if the system's resistance doesn't change. If we turn on a landing light, we decrease resistance which increases current flow which decreases voltage which tells the regulator to feed more current to the rotor to get the alternator to make more current to get the voltgae back to normal.

The battery will take considerable current when recharging after start. As it gets to system voltage, the regulator starts tapering off the field current to reduce the alternator's output. It's not a case of all or nothing. No breakers should pop. The regulator is capable of feeding nothing at all to the alternator, or it can feed the max current (around 4 amps in a 14-volt 60-amp alternator). It does whatever is necessary to maintain the set voltage. (BTW, you can see the way an alternator, using mechanical energy, turns a 4-amp investment into a 60-amp return, right?)

If a breaker popped, it was probably the 60-amp alternator output breaker. And using 60 amps takes some doing, believe me. In most light airplanes you can turn on everything and never use that much. Breakers do get tired when they get old; their contacts oxidize and start generating resistance. They're a thermal thing anyway, heating a tiny bimetal strip inside themselves with the current flowing thorugh them and tripping off when that bimetal strip warps under the heat at the relevant current flow and causes a small mechanism to open the contacts. Corroded contacts make more heat and they start tripping off at much lower current flows. Or sometimes you might have a crimp terminal connection that has oxidized or come loose and is getting hot and the breaker's terminal is conducting that heat into the breaker and fooling it into tripping.

 

[JAWS]

Always troubleshoot

Better to be on the ground, wishing you were in the air, than in the air wishing you were on the ground!
https://en.wikipedia.org/wiki/Alaska_Airlines_Flight_261
https://en.wikipedia.org/wiki/Alaska_Airlines_Flight_261

 

[Chris Fischer]

Better to be on the ground, wishing you were in the air, than in the air wishing you were on the ground!
https://en.wikipedia.org/wiki/Alaska_Airlines_Flight_261

That was a sad day, a high school classmate of mine was on that flight. We went to the same university as well, but this happened several years after that when he was 33. In a nutshell, the NTSB determined the crash was due to shoddy maintenance - specifically in regards to improper lubrication of the jackscrew assembly in the horizontal stabilzer:

"This is a maintenance accident. Alaska Airlines' maintenance and inspection of its horizontal stabilizer activation system was poorly conceived and woefully executed. The failure was compounded by poor oversight...Had any of the managers, mechanics, inspectors, supervisors or FAA overseers whose job it was to protect this mechanism done their job conscientiously, this accident cannot happen...NTSB has made several specific maintenance recommendations, some already accomplished, that will, if followed, prevent the recurrence of this particular accident. But maintenance, poorly done, will find a way to bite somewhere else."

 

[Clip4]

You know what is interesting is I distinctly remember the oil pressure and oil temp gauges were still working fine which is why I felt confident the engine was still working fine. It's really weird how and which things failed in this situation. I'm very eager to speak to the mechanic again to see what they discovered and what steps they took to remedy the issue!

With regards to the low voltage light, I can tell you for sure it never came on and the amp meter never showed a discharge. I checked both thinking they should be registering a discharge or be illuminated and they were not. Again, this is why I was getting confused about what was actually going on since the indications I was expecting to see did not match what I thought was happening and this created that urgency to land I've described several times.

I do believe this adds another layer to the conversation though and that is, why do single engine airplanes have indicators that are often misleading to the pilot or essentially useless? Seems like they are not even worth having as some have said. I would have liked to have had a voltage indicator directly connected to the battery or something like that so I could have seen exactly how much voltage the battery was producing! If that would have been on board and I could have seen it reading 2 amps or 0 or whatever I would have had an easy way to know exactly what was happening!

To have the avionics fail, the fuel gauges fail, the flaps fail, and the oil/temp gauge remain operative would be very unlikely. If the amp meter was still indicating a load, where is the electricity going? Possibly a short and a fire potential. That is why the checklist tells you to land as soon as practical.

I suspect your mechanic is going to find a control unit failed.

 

[denverpilot]

...so we feed that AC through six diodes to sort it out into DC.

I think you have two more diodes than necessary in your bridge rectifier...

 

[Skyrys62]

A little late, but I'll give my .02. You did well by getting yourself back to the airport with no bent metal or FAA repercussions. Kudos on that. However, you keep reiterating that your first choice of action for any failures is to get back on the ground immediately and let the mechanic sort it out. I believe that to be a bit short-sighted. We have the emergency checklists and POH checklists for a reason, and you should revert to those first as long as there isn't a more pressing emergency (like an in-flight fire). When landing - use the checklist. When the engine stops - use the checklist. When you lose electrical power - use the checklist. They exist for the sole purpose of being the primary quick reference material for normal and abnormal operations. Again, you did well by returning home and not pranging metal in the process, but the important thing to take away was that you should have more knowledge on how to do it better if it should occur again. You could have shed enough load/reset the main breakers to at least have enough power to communicate the issue with ATC get the 7600 ping out there, which could have assisted in getting you back home with less anxiety. If your instruments came back to life, you would have seen the fuel gauges return to normal, which would have calmed your fears about running out of fuel. In the end, you're still a pilot, with a bit more experience to add to your bag.

This, exactly.

And thanks for posting.
I have since both learned and been reminded of the following:

Always use the checklist
Use your phone if possible
Get a handheld with AA batteries (and keep it handy)
Use a slip when no flaps are available
Have your passengers help and keep them calm
I can land with someone else on the runway at an uncontrolled airport without being imprisoned
I can fly the pattern above TPA and wait for the tower light signals
Highwings are better than low wings
Paper charts are better than electronics

oh..sorry..mixed up some threads there.

Anyhoo, glad you are safe, and today, you are a better pilot.

 

[mondtster]

Right, and my post was maybe a bit tongue in cheek... but that's still kind of a pathetic light in my opinion. Maybe when these planes were new it was the simplest way to provide a warning light that could address an array of problems, but I still prefer an actual indication of the voltage to the battery, or at least an ammeter that didn't seem pegged on zero. The Piper I fly seems to have a more indicative ammeter, you can see it "pick up the load" (so to speak) when you hit the pitot heat, etc. I've read on other forums that those voltage lights on the old Skyhawks don't get much love. I hate to sound like a Cirrus fanboy (esp because I don't consider myself one) but seeing the two buses, the loads, etc. right there is very convenient. Oh well... 2000s technology I guess vs 1950s

The airplane charging and indication systems on the older airplanes many of us fly were very similar to the cars from the same era. Most cars had either a warning light or an ammeter that showed a charge/discharge indication like the Cessnas, and that was it.

Just like the charge/discharge ammeter in the Cessnas, you have to know what the load meter is indicating in a Piper. What is the load meter going to indicate when the alternator has failed? What is the load meter going to indicate when no lights or radios are on? What is the load meter going to indicate when you have everything turned on and the current draw is more than the alternator can put out?

The biggest problem plaguing many of these old airplanes is age and neglect. Regardless of the method of indication the charging systems rarely seem to get attention and when they do it is often by a mechanic that has minimal knowledge of how the system works. Then the only attention it will get is whatever it takes to make it work long enough to get it out of the shop.

 

[mondtster]

I think you have two more diodes than necessary in your bridge rectifier...

Dan is right. There are six.

 

[denverpilot]

Dan is right. There are six.

He is. But not because you need six to get DC from AC...

(Edit: Ick. That was a horrible stolen graphic. Here's a better one.)

Hint: Answer has something to do with phases...

 

[Sundancer]

This, exactly.

And thanks for posting.
I have since both learned and been reminded of the following:

Always use the checklist
Use your phone if possible
Get a handheld with AA batteries (and keep it handy)
Use a slip when no flaps are available
Have your passengers help and keep them calm
I can land with someone else on the runway at an uncontrolled airport without being imprisoned
I can fly the pattern above TPA and wait for the tower light signals
Highwings are better than low wings
Paper charts are better than electronics

oh..sorry..mixed up some threads there.

Anyhoo, glad you are safe, and today, you are a better pilot.

At Hemet-Ryan, back in tbe 70's, a guy was dead-stick, for real - my instructor and I were watching, and a local pulled onto the runway, and proceded to "position and hold", oblivious. He wasn't listening or talking, for whatever reason. The engine failure side-stepped to the taxi-way, passed over us, and landed on it.

 

[mondtster]

He is. But not because you need six to get DC from AC...

(Edit: Ick. That was a horrible stolen graphic. Here's a better one.)

Hint: Answer has something to do with phases...

I'm well aware of that. But we're talking about what's in an alternator. That's not what's inside.

 

[Dan Thomas]

He is. But not because you need six to get DC from AC...

(Edit: Ick. That was a horrible stolen graphic. Here's a better one.)

Hint: Answer has something to do with phases...

This is what's in the alternator. It's a three-phase affair and need six diodes.

 

[JAWS]

That was a sad day, a high school classmate of mine was on that flight. We went to the same university as well, but this happened several years after that when he was 33. In a nutshell, the NTSB determined the crash was due to shoddy maintenance - specifically in regards to improper lubrication of the jackscrew assembly in the horizontal stabilzer:

"This is a maintenance accident. Alaska Airlines' maintenance and inspection of its horizontal stabilizer activation system was poorly conceived and woefully executed. The failure was compounded by poor oversight...Had any of the managers, mechanics, inspectors, supervisors or FAA overseers whose job it was to protect this mechanism done their job conscientiously, this accident cannot happen...NTSB has made several specific maintenance recommendations, some already accomplished, that will, if followed, prevent the recurrence of this particular accident. But maintenance, poorly done, will find a way to bite somewhere else."

This is the part I was getting at:

"Also included was a recommendation that pilots were to be instructed that in the event of a flight control system malfunction they should not attempt corrective procedures beyond those specified in the checklist procedures, and in particular in the event of a horizontal stabilizer trim control system malfunction the primary and alternate trim motors should not be activated, and if unable to correct the problem through the checklists they should land at the nearest suitable airport."

There is a time and a place to troubleshoot. In the air, feeling over loaded, unfamiliar with what is going on, is not the time or place to troubleshoot. I think the OP made the right call in his given circumstances.

 

[denverpilot]

This is what's in the alternator. It's a three-phase affair and need six diodes.

Yup. It's three phase AC, not just AC.

 

[Tantalum]

As it gets to system voltage, the regulator starts tapering off the field current to reduce the alternator's output.

That makes sense, as the red light very dimly flickered to life over the span of about a minute, and then maybe 10 minutes later started flickering again and dimly went out, and subsequently stayed out

I'm no engineer but my father and father in law both are and I played around with electronics a few years ago, even built a small windmill and made my own copper wire loop with magnets, etc... it was neat. Definitely props to Tesla, Ohm, and the others who laid the foundation of electrical knowledge

 

[JAWS]

Now that the OP is on the ground.

https://www.zeftronics.com/wp-content/uploads/2014/06/Z13PS.pdf

 

[jspilot]

This is the part I was getting at:

"Also included was a recommendation that pilots were to be instructed that in the event of a flight control system malfunction they should not attempt corrective procedures beyond those specified in the checklist procedures, and in particular in the event of a horizontal stabilizer trim control system malfunction the primary and alternate trim motors should not be activated, and if unable to correct the problem through the checklists they should land at the nearest suitable airport."

There is a time and a place to troubleshoot. In the air, feeling over loaded, unfamiliar with what is going on, is not the time or place to troubleshoot. I think the OP made the right call in his given circumstances.

Your last paragraph is exactly how I felt throughout the situation. I do wish I would have run the checklist because it would have helped but either way my choice to return to the airport was the only one I was going to make.

As some are now indicating, perhaps even if I would have trouble shooted and got the radios back on their may have been a larger issue going on than the simple alternator failure. So let's play that situation out, I trouble shoot, believe I have fixed the problem( really all I've done is mask the cause of the initial problem) possibly decide to continue on my way believing the cause has been fixed by my troubleshooting and now about half way between Montauk Point and Block Island the plane catches fire because of some larger issue that probably caused the radio to fail and now I'm totally over water with nothing to possibly help me.

Had I done that I may not be here today. Had I run a checklist I may have helped myself on the return flight to the airport and while in the pattern. I do firmly believe though that we all should consider a simple return to the airport when something amiss goes on. Troubleshooting may help make the situation better but again fixing should be done on the ground not in the air!

Also, given the diagram you shared, and the fact that the Alt Field breaker was the one that popped I think I can assume that the Controller part of the circuit must have been a major cause of issue. For those that can figure this out better than me is this the most likely conclusion?

 

[MauleSkinner]

You know what is interesting is I distinctly remember the oil pressure and oil temp gauges were still working fine which is why I felt confident the engine was still working fine. It's really weird how and which things failed in this situation. I'm very eager to speak to the mechanic again to see what they discovered and what steps they took to remedy the issue!

Analog pressure and temperature gauges typically don't require electricity in light airplanes.

With regards to the low voltage light, I can tell you for sure it never came on and the amp meter never showed a discharge. I checked both thinking they should be registering a discharge or be illuminated and they were not. Again, this is why I was getting confused about what was actually going on since the indications I was expecting to see did not match what I thought was happening and this created that urgency to land I've described several times.

by the time your radios blinked, there probably wasn't enough voltage to illuminate; if there's not enough voltage to run your radios or other electrical components, there will be no discharge indication because the battery is already discharged. If you were going to see these indications, you'd need to look before the radios blinked out.

I do believe this adds another layer to the conversation though and that is, why do single engine airplanes have indicators that are often misleading to the pilot or essentially useless? Seems like they are not even worth having as some have said. I would have liked to have had a voltage indicator directly connected to the battery or something like that so I could have seen exactly how much voltage the battery was producing! If that would have been on board and I could have seen it reading 2 amps or 0 or whatever I would have had an easy way to know exactly what was happening!

They're not misleading or useless, you just have to understand what they're telling you...for instance, a volt meter doesn't show amps.

Yeah, it'd be great to have all the stuff we'd like in an airplane, but sometimes (most of the time, really) we have to simply be able to use what's there, which should be adequate to the task.

 

[FLYGUYRY]

Good story and glad you had a good outcome. Funny that this happened to you, had a similar (but not as bad) situation this past weekend as well. I was flying with my dad (his first time in a small plane, of course) on Friday and took off out of KHGR IFR, got to cruise altitude and I got a low voltage annunciator (G1000 C172), took a look at my voltage readings and sure enough, batt was draining at about -8, nothing charging. I checked the breakers and they were all in, shut off the alt switch and back on a few times to see if it would cycle and nothing. I told ATC I had a low voltage annuciator and needed vectors to go back to HGR, they gave me HGR direct and asked if I was declaring an emergency, which I knew I didn't need to do. Got back on the ground and called my flight instructor who told me that for whatever reason the SPs sometimes won't reset with the engine running, and that I did the right thing turning around. I got the plane going again and all was well, flew it the next day too no issues but it certainly was good experience (and my first in 150 hours) turning back to the field. Certainly better than your situation but I had no idea how long that battery would really last before it turned into your situation

 

[MauleSkinner]

As some are now indicating, perhaps even if I would have trouble shooted and got the radios back on their may have been a larger issue going on than the simple alternator failure. So let's play that situation out, I trouble shoot, believe I have fixed the problem( really all I've done is mask the cause of the initial problem) possibly decide to continue on my way believing the cause has been fixed by my troubleshooting and now about half way between Montauk Point and Block Island the plane catches fire because of some larger issue that probably caused the radio to fail and now I'm totally over water with nothing to possibly help me.

Had I done that I may not be here today. Had I run a checklist I may have helped myself on the return flight to the airport and while in the pattern. I do firmly believe though

I don't think anyone's arguing that landing was a bad choice...I think the argument is forgoing any form of checklists or troubleshooting on the way so that you know exactly what you're dealing with and the true urgency (or lack thereof) of the situation.

Troubleshooting/running checklists and landing are not mutually exclusive.

 

[Clip4]

Analog pressure and temperature gauges typically don't require electricity in light airplanes.

by the time your radios blinked, there probably wasn't enough voltage to illuminate; if there's not enough voltage to run your radios or other electrical components, there will be no discharge indication because the battery is already discharged. If you were going to see these indications, you'd need to look before the radios blinked out.

They're not misleading or useless, you just have to understand what they're telling you...for instance, a volt meter doesn't show amps.

Yeah, it'd be great to have all the stuff we'd like in an airplane, but sometimes (most of the time, really) we have to simply be able to use what's there, which should be adequate to the task.

Your statement is incorrect. Most older aircraft typically have fuel and oil pressure gauges that are not electrical. A line from the engine is routed to the gauge. That is not true of temperature gauges which normally consist of an electric gauge and a sending unit on the engine. Typically in newer aircraft, fuel and oil pressure gauges are electric.

 

[Piperonca]

Sully rehearsed that exact river landing scenario many times in his head before actually doing it. How is that being a hero? AND, He did make one big mistake that could have cost him the title.

What mistake was that?