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Flying with alternator switched off causes total loss of engine power

GalinHdz

Well Known Member
The private pilot/owner of the experimental, amateur-built airplane reported that, about 15 minutes into the local flight, the engine started "skipping" before completely losing power. He then set up for a forced landing to an open area. During the descent, he maneuvered to clear power lines. The airplane touched down at a steep descent angle, nosed over, and came to rest inverted, which resulted in substantial damage to the airframe.

The airplane's engine used an electronic control unit instead of magnetos and required at least one of the airplane's two onboard batteries to provide electrical energy to the ignition system for the engine to operate. Post accident examination of the airplane revealed that both of its batteries were discharged. After the batteries were charged, the engine was started and ran normally. The alternator also charged the batteries normally. The cockpit instrument panel switch that enabled the alternator to supply energy to the airplane's electrical system, and thus charge the airplane's batteries, was unlabeled. When the switch was placed in the unlabeled on position, the alternator field wire received power and the alternator charged normally. The pilot reported that he may have inadvertently left it in the off position during the flight. With the switch in this position, the engine would have continued to run until the selected battery lost its charge. The pilot also reported that he did not use a checklist when operating the airplane. It is likely that the pilot failed to activate the airplane's alternator, which resulted in a discharge of the selected battery during the 15-minute flight. The subsequent loss of electrical power eventually resulted in the total loss of engine power.

Additionally, the airplane was not equipped with an alternator warning light as recommended by the engine manufacturer. Had the airplane been equipped with such a light, the pilot might have realized that he had failed to turn the alternator on and that it was not providing energy to the electrical system to sustain the charge of the selected battery.


Copied from NTSB Report ERA18TA263

This is why my electronic ignition has it's own built in alternator and doesn't require anything externally to continue running.

:cool:
 
It’s why my airplane has its alternator field circuit tied to the master switch, has an alternator warning light, and has low voltage warning on my EMS.

The fact that his ignition needed power was pretty far down the failure tree.
 
Sounds a lot like Vic's story about the guy who made a forced landing with fuel in a tank, because he neglected to switch after the engine went quiet.

The electronic control unit in this case wasn't just ignition. Full narrative says Viking 110.

This is why my electronic ignition has it's own built in alternator and doesn't require anything externally to continue running.

Don't forget to check the self-powered function on a regular basis. I've found 'em inop in pre-buys, and there is no warning system. That said, there are two of them, so total ignition loss would require a minimum of three failures, power and both self-generators.

It’s why my airplane has its alternator field circuit tied to the master switch, has an alternator warning light, and has low voltage warning on my EMS.

Same here, plus an independent voltage monitor on the IGN2 battery, complete with warning light and beeper. The alternator is auto-on, and if it quits charging, I'd need to be deaf and blind to miss it.
 
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The Viking engine is equipped with EFI/EI and is electrically dependent. In this case, it had 3 power sources installed, 2 of which were effectively not available due to pilot mismanagement. The lack of the recommended voltage warning system and switch labeling (none) were contributing factors.

Nothing failed here except the pilot/builder...
 
To save you a click

Hopefully this will save you a click. So many lessons in one report!

NTSB Identification: ERA18TA263
On September 23, 2018, about 1545 eastern daylight time, a Zenith Aircraft Company CH 750, N752VK, was substantially damaged following a forced landing near DeLeon Springs, Florida. The private pilot and one passenger sustained minor injuries. The airplane was operated by the pilot under the provisions of Title 14 Code of Federal Regulations Part 91 as a personal flight. Visual meteorological conditions prevailed, and no flight plan was filed for the local flight that originated from DeLand Municipal Airport (DED), DeLand, Florida, about 1530.

The pilot/owner reported that while over the DeLeon Springs area, the engine started "skipping." The engine then lost all power and the propeller stopped. He set up for a forced landing to an open area. During the descent, he observed power lines and maneuvered to clear them. The airplane touched down at a steep descent angle. After touchdown, the airplane nosed over and came to rest inverted.

An inspector with the Federal Aviation Administration responded to the accident site and examined the wreckage. He reported that the engine firewall, wings, and vertical stabilizer had structural damage. Further examination of the wreckage revealed that the airplane was equipped with two 12v motorcycle batteries, and both were discharged. One battery indicated 0.75 volts and the other indicated 7 volts. Both batteries were then charged by the inspector and a mechanic, who were then able to start the airplane's Viking 110 engine normally. The alternator was found to be charging normally with the engine running and the bus voltage was greater than 13.5 volts.

The key-actuated rotary (ignition) switch on the cockpit instrument panel controlled the airplane's alternator and started the airplane's engine was unlabeled. When the switch switch was placed in the unlabeled on position, the alternator field wire received power and the alternator charged normally. When placed to the unlabeled off position, power was removed from the alternator field wire, and the engine continued to run as long as one of the unlabeled battery toggle switches was turned on. The Viking 110 engine manual recommended an alternator warning light installation; however, the inspector noted that there was no light installed.

The pilot reported to the FAA inspector that he may have left the alternator switch in the unlabeled off position by mistake. The pilot also reported that he did not utilize a checklist when operating the airplane.

The Viking 110 engine manual reminds operators that the engine is controlled by an electronic control unit (ECU) versus mechanically operated magnetos and at least one battery must maintain its charge for the engine to operate.
 
Don't forget to check the self-powered function on a regular basis. I've found 'em inop in pre-buys, and there is no warning system.
Prior to every flight as part of the engine run up procedure in my airplane's check list.

That said, there are two of them, so total ignition loss would require a minimum of three failures, power and both self-generators.
Actually four failures. Alternator, airplane main battery and both self-powered generators. If this happens then the good lord really wants me to depart this Earth.

;)
 
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Yikes!

For the pmag folks ...

For anyone that retros pmags and doesn't know how to install a proper test circuit, it's not that hard, please reach out for help.

It's easy to test pmags during your run up to verify working generators, takes all of 6 seconds.
 
A good example of several things being done wrong. Any one of which could have either prevented the situation or at least indicated to the pilot the corrective action.
 
Another small mystery here...

There’s also the question of why were both batteries dead? Alternator off, so the first battery started the motor and ran the motor, until it didn’t. But what’s the point of having a backup battery if it isn’t charged. Or from the report, not selected either....
 
Good cautionary tail. My new-to-me RV-9A has a (labeled) alternator switch, something I haven’t been used to in my decades of flying. Gotta remember to turn it on. It also has two switched batteries in parallel as well as two E-Mags. Their alternator function was checked at the condition inspection/pre-buy.
 
Good cautionary tail. My new-to-me RV-9A has a (labeled) alternator switch, something I haven’t been used to in my decades of flying. Gotta remember to turn it on. It also has two switched batteries in parallel as well as two E-Mags. Their alternator function was checked at the condition inspection/pre-buy.

Check the pmag alternator function during every run-up. Run the engine up to 1800 rpm or so, then when you do your normal mag check, switch off the ship’s power to each pmag in turn, while the engine is running on that mag. (Hopefully, your installation includes these power interrupt switches. Otherwise, you would have to pull a breaker.). The pmags generate their own power when the engine is above about 800 rpm. If the internal generator has failed, you will know it when you switch off ship’s power. Fast and easy to check. :)

Edit: I just realized you wrote you had Emags. If that is true, they do not have an internal generator. Emags have not been manufactured for several years, but yours may be an old installation.
 
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There’s also the question of why were both batteries dead? Alternator off, so the first battery started the motor and ran the motor, until it didn’t. But what’s the point of having a backup battery if it isn’t charged. Or from the report, not selected either....

The second battery probably was charged at first and ran down along with the other one with both switched on. A second battery is not a back up if it isn't held in reserve.

I have an electrically dependent engine and panel, two batteries, and two battery contactors. I have only one alternator and no alternator switch, just a pullable field breaker. The field is energized by either or both of the contactor switches. I normally close both contactors before engine start for faster spin and, once it starts, the alternator is running and charging both batteries. In the case of alternator failure, I would switch off one of the batteries to preserve it for later and run the other one down to about 10.5V (lead acid battery) before going to the reserve battery and getting on the ground at an airport of my choosing. I also have both batteries wired so that I can power my E-bus with either or both and not burn an amp on keeping the contactor closed. Yes, I do regularly check that the E-bus works with either switch and that either switch closes its respective contactor. Yes, I have good non-alternator load calcs.

Having a low voltage warning light is essential in an electrically dependent design. The pilot absolutely needs to have notice that the alternator is offline so that battery power can be managed. It is important that the battery(ies) be regularly capacity checked and that the pilot knows how long the system will operate with no alternator. That way an alternator failure is not an immediate emergency and never becomes one.

Ed Holyoke
 
i have a viking 110 installed. it is operated on battery #1 or battery #2. it will also operate on only the alternator if both batteries go bad. batteries are earth x, each with its own warning light. my charging system has a warning light. each warning light has its own ''mini'' momentary switch to test each light before flight. i have a switch to turn on the alternator field and a 70 amp breaker on the b lead between the alternator and the bus. i also have an ovm on the b lead between the alternator and the breaker.
 
Another one of my pet peeves--- unlabeled switches!!!

Vic

I recently finished a CI on a "professionally built" RV14 with $$ glass, mag and a pmag. The pmag was never powered from external power from day 1, I figured out that a switch labeled 'com 2' was actually pmag pwr, however the owner never could figure out what the switch did so he just left it off.
 
Edit: I just realized you wrote you had Emags. If that is true, they do not have an internal generator. Emags have not been manufactured for several years, but yours may be an old installation.
E-Mag is out of business?...I suspect they’d be surprised to hear that, and somebody should let Spruce know...:)

https://emagair.com/

https://www.aircraftspruce.com/catalog/eppages/eMagIgnition.php

As to internal alternator...they say they have one, and my A/P tested for one and thought he found one.......but I’ve just come out of the dark certificated world into the light of the Experimental day. It would be easy to fool me.
 
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The "Emag" product, distinct from the "Pmag" product, has not been manufactured by Emagair (the company) in several years.
 
The "Emag" product, distinct from the "Pmag" product, has not been manufactured by Emagair (the company) in several years.

Ah. I see...semantics. You’re saying that the current version of electronic ignition that E-Mag Air sells is the “P-Model”, which is self-powered. Yes. Now I get it. That’s what I have.
 
E-Mag is out of business?...I suspect they’d be surprised to hear that, and somebody should let Spruce know...:)

https://emagair.com/

https://www.aircraftspruce.com/catalog/eppages/eMagIgnition.php

As to internal alternator...they say they have one, and my A/P tested for one and thought he found one.......but I’ve just come out of the dark certificated world into the light of the Experimental day. It would be easy to fool me.

Emag, the company is alive and well. They now produce an electronic mag called a Pmag, which has an internal generator. They no longer produce an Emag, which did not have an internal generator. So, my previous description of how to test a Pmag during every pre-flight run-up apparently does apply to your electronic mags. Sorry if I created any confusion. ;)
 
For EDA (electrically dependent aircraft), checklist items should include sitting battery voltage for primary and backup and charging voltage from the alternator once the engine is running. Unless all 3 are good, don't fly. Simple stuff...
 
I apologize for the semantic confusion as well. E-Mag the company no longer makes the E-model of their electronic ignition (since many years), they now only make the P-model, which generates its own power once you hit 900 RPM (can't hand-prop). Some people apparently call the P-model P-Mags, which is where the confusion lies. They are actually the P-model of E-Mag's electronic ignition. For clarification...there is no actual "P-mag" only P-model of E-mag's electronic ignition line-up.

It really becomes confusing if what you are actually looking for is a high-capacity magazine for your AR-15/M-16.
 
Now I wonder why mankind invented magneto's?
The 'KISS' method has kept man alive for many years:)
 
Now I wonder why mankind invented magneto's?
The 'KISS' method has kept man alive for many years:)
Yes, and it's curious why folks will try to reinvent the fuel system to be totally dependent on electrical power. I like the mechanical pump/electric pump setup just fine.
 
Yes, and it's curious why folks will try to reinvent the fuel system to be totally dependent on electrical power. I like the mechanical pump/electric pump setup just fine.

For the same reason you no longer drive a Model T - there is something better.
 
Now I wonder why mankind invented magneto's?
The 'KISS' method has kept man alive for many years:)

True, however mankind did switch from steam engines to gas and horses to autos among a few other changes over the last hundred years.
 
For the same reason you no longer drive a Model T - there is something better.

Yea, and now every time the 'check engine' light comes on it costs an arm and leg to fix. Ign/fuel systems have turned into computer systems and instead of a new $2 set of points and condenser or a carb ovhl kit that any kid in a 'gas station' could install it costs thousands to repair and only the dealer has the computer to diagnose your computer problems.

I guess that's why I prefer old dinosaur engines... simple/reliable/easy for the average mechanic to work on.
 
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It sounds crazy, but at one time, pilots flew their planes based on nothing but a bunch of little round gauges on the instrument panel, and they didn't even have GPS to get them from point A to point B.
 
I offer the primary lesson learned from this accident has so far been mostly glossed over.

For those who choose to build with an electrically dependent engine, you cannot just cobble together whatever the manufacturer instructions say and go fly. You must have the basic system knowledge to know:
- The design characteristics.
- How it all works as a ship system.
- Normal operating indications.
- Abnormal operation indications.
- Emergency actions.

You also need to know, and adhere to system maintenance - for electrically dependent engines this includes your ship power system.

Here is a simple exercise. Take out a sheet of paper and a stubby pencil and draw, from memory, a block diagram of your airplane’s electrical distribution. This level of knowledge will pay dividends when the little red light on the panel comes on for you to figure out what happened - and what actions you need to take.

This is even more important for those who buy their RV.

As a data point, I know of one RV (standard engine) with dual alternators and three batteries that lost all electrical power before (safely) landing.

Be safe out there,
Carl
 
Yea, and now every time the 'check engine' light comes on it costs an arm and leg to fix. Ign/fuel systems have turned into computer systems and instead of a new $2 set of points and condenser or a carb ovhl kit that any kid in a 'gas station' could install it costs thousands to repair and only the dealer has the computer to diagnose your computer problems.

I guess that's why I prefer old dinosaur engines... simple/reliable/easy for the average mechanic to work on.

I think you have a 30 year old perspective on modern automobile electronics. Is it better to be able to repair a points distributor on the side of the road many times in your life, or have the ignition system last the life of the car with ZERO maintenance? If "fleet dispatch reliability" is the goal, then the choice is very clear.

And no, it does not cost thousands of dollars every time the check engine light comes on. You can buy inexpensive scanners and even ones that WiFi to a smartphone or tablet to diagnose the codes. In most cases it's a simple sensor failure or a loose gas cap throwing a code.

I grew up working on/hotrodding late 60's muscle cars in an era when these were just well worn, used cars. I KNOW how to rebuild a Quadrajet carb in the auto parts parking lot at midnight... Yet I wouldn't go back to that if you paid me. My 2008 Corvette (which I bought brand new) has been FAR more reliable, faster, and more comfortable than any of the cars I had back in my early days.

Times change.

As for the scenario in the OP, yep, pilot error all the way. Same as taking off on the left tank and running it dry without switching.
 
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Here is a simple exercise. Take out a sheet of paper and a stubby pencil and draw, from memory, a block diagram of your airplane’s electrical distribution. This level of knowledge will pay dividends when the little red light on the panel comes on for you to figure out what happened - and what actions you need to take.

This is a good exercise, but I approach design a bit differently. The user shouldn't have to know anything about the internals in order to safely continue to operate (or shut down) the system or subsystems in the event of a failure of a component. That is to say, troubleshooting in the the air should be minimized if not eliminated altogether.

Light X goes on, do Y. Low voltage, do Z. Etc. If I have to figure out the electrical pathways in flight, I haven't done a good job of designing the system.
 
This is a good exercise, but I approach design a bit differently. The user shouldn't have to know anything about the internals in order to safely continue to operate (or shut down) the system or subsystems in the event of a failure of a component. That is to say, troubleshooting in the the air should be minimized if not eliminated altogether.

Light X goes on, do Y. Low voltage, do Z. Etc. If I have to figure out the electrical pathways in flight, I haven't done a good job of designing the system.

I don't want to start a war but this is not consistent with how I was trained to operate systems. Memorizing emergency actions is good, but no substitute for system knowledge - and why you are taking such actions. Invariably you will be presented with a situation that does not fit nicely into one of your canned scenarios.

I'm not advocating troubleshooting. This is strictly maintaining safety of flight when bad stuff happens. For the subject at hand, electric dependent engines, this is especially critical.

Carl
 
Nobody wrong here. Can't determine the pre-planned action (Jim's view) unless you really do know the system (Carl's view).
 
To those that advocate we have moved on from T model Fords have it all wrong! T model Fords are no longer made (and for good reason) but MAGNETO's are still being made new & utilised the world over!
It's about choice. You either accept the higher complexicity of today's fancy gizmo's or you open your hangar doors and go flying full knowing the whole shooting match can go dark at any time and your engine will bring you home safe, your choice:)
 
To those that advocate we have moved on from T model Fords have it all wrong! T model Fords are no longer made (and for good reason) but MAGNETO's are still being made new & utilised the world over!
It's about choice. You either accept the higher complexicity of today's fancy gizmo's or you open your hangar doors and go flying full knowing the whole shooting match can go dark at any time and your engine will bring you home safe, your choice:)

After I finished mining the bauxite and smelting ore to mix my own aluminum alloy and extruding it into the pieces I needed to build my airplane, I decided I have had enough of doing things the hard way.
 
I offer the primary lesson learned from this accident has so far been mostly glossed over.

For those who choose to build with an electrically dependent engine, you cannot just cobble together whatever the manufacturer instructions say and go fly. You must have the basic system knowledge to know:
- The design characteristics.
- How it all works as a ship system.
- Normal operating indications.
- Abnormal operation indications.
- Emergency actions.

You also need to know, and adhere to system maintenance - for electrically dependent engines this includes your ship power system.

Here is a simple exercise. Take out a sheet of paper and a stubby pencil and draw, from memory, a block diagram of your airplane’s electrical distribution. This level of knowledge will pay dividends when the little red light on the panel comes on for you to figure out what happened - and what actions you need to take.

This is even more important for those who buy their RV.

As a data point, I know of one RV (standard engine) with dual alternators and three batteries that lost all electrical power before (safely) landing.

Be safe out there,
Carl

Doesn't matter what you have for an electrical layout if the pilot makes so many fundamental errors in airmanship and the builder ignores proper switch labeling when we are talking about an EDA. No electrons= no engine run.

Had the pilot used a proper checklist or even bothered to verify charging voltage (100% must in my view on an EDA prior to flight), the accident would have never occurred.

Of course a standard engine will continue to run without a battery or alternator. That has nothing to do with this thread.

The investigation clearly showed that this was pilot malfunction, not system malfunction as everything worked as it should have once the switches were in the proper position again.
 
I don't want to start a war but this is not consistent with how I was trained to operate systems. Memorizing emergency actions is good, but no substitute for system knowledge - and why you are taking such actions. Invariably you will be presented with a situation that does not fit nicely into one of your canned scenarios.

I'm not advocating troubleshooting. This is strictly maintaining safety of flight when bad stuff happens. For the subject at hand, electric dependent engines, this is especially critical.

Carl

I agree, system knowledge is a really good idea and this pilot either didn't have any or didn't think about it. Only a fool begins a flight in an EDA without verifying that the alternator is working. Ditto making sure that both batteries show proper voltage. Who hops into a strange plane (especially one with atypical systems) without at least a cockpit checkout? Again- only a fool.

How many times have we seen accidents happen (of many types) because someone didn't use checklists? I'd argue that even though someone doesn't have a complete system knowledge, they have a good chance of catching something wrong by always using the checklist. Having knowledge AND using the checklist gives you the best chance to complete your flight safely.
 
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Ross is exactly correct - in an EDA airplane electron supply is just as critical as fuel supply. You ignore either one at your own peril. Darwinism is real.
 
How many times have we seen accidents happen (of many types) because someone didn't use checklists? I'd argue that even though someone doesn't have a complete system knowledge, they have a good chance of catching something wrong by always using the checklist. Having knowledge AND using the checklist gives you the best chance to complete your flight safely.

Well said!!!

FWIW, I designed and installed the entire electrical/avionics suite in my airplane to include dual E-mags for ignition. Even though I have over 1,100hrs of flying my airplane, I use the check list on every flight. You can see the checklist on the top right of the panel in this photo.

b3c2.jpg


I guess my Air Force training is permanently burnt in to me, and that is a good thing.

 
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