Alternator failure--What would you do?

Pa28-140

Pre-takeoff checklist
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Gordon Shumway
I had an unusual occurrence today flying my friend's C182 and thought I would seek some opinions. I was on an IFR flight plan, although the weather was CAVU and was about an hour and a half into a three hour flight when the alternator failed. Multiple attempts to get it back on line failed. I could easily have cancelled IFR and continued to my destination VFR without a problem. However, the airport I was going to was in the middle of Nowhere Kansas with limited/no services available. To continue, I had two primary concerns. #1 would I have enough battery to start the airplane for the return trip? #2 Would I have enough battery on the return leg to contact the tower for D airspace and landing clearance?

Since I had no idea how long the battery might last, even with everything shut down, I elected to return to my home airport (leaving my friend semi-stranded in the middle of Nowhere Kansas. The enroute center was nice enough to phone my friend and advise him that I had turned around). I continued to try getting the alternator back on line and my last attempt was on final approach at my home airport, with still no luck.

Here are my questions: #1. With a good battery and power usage minimized, how long could I reasonably expect the battery to last for necessary radio and transponder usage? (I would have been within the 30 mile veil of Class B upon return.) #2. Would you have continued the flight VFR or not?

Oh yeah, here's the kicker. After I landed I tried the alternator again and it came back on line without further issue :mad2:. Most likely there is a loose wire or something. Regardless, it didn't work during the flight. By the way, my friend was able to get ground transport home......eventually. Thanks for the input.
 
I had an unusual occurrence today flying my friend's C182 and thought I would seek some opinions. I was on an IFR flight plan, although the weather was CAVU and was about an hour and a half into a three hour flight when the alternator failed. Multiple attempts to get it back on line failed. I could easily have cancelled IFR and continued to my destination VFR without a problem. However, the airport I was going to was in the middle of Nowhere Kansas with limited/no services available. To continue, I had two primary concerns. #1 would I have enough battery to start the airplane for the return trip?
So you were planning to re-depart with a known deficiency.
#2 Would I have enough battery on the return leg to contact the tower for D airspace and landing clearance?
And were worrying about legality.
Since I had no idea how long the battery might last, even with everything shut down, I elected to return to my home airport (leaving my friend semi-stranded in the middle of Nowhere Kansas.
You did good :).
The enroute center was nice enough to phone my friend and advise him that I had turned around). I continued to try getting the alternator back on line and my last attempt was on final approach at my home airport, with still no luck.

Here are my questions: #1. With a good battery and power usage minimized, how long could I reasonably expect the battery to last for necessary radio and transponder usage? (I would have been within the 30 mile veil of Class B upon return.) #2. Would you have continued the flight VFR or not?
I think you can tell how I think about this one. You did good. Just ask John and Martha King about their "we can still do this" last event...
Oh yeah, here's the kicker. After I landed I tried the alternator again and it came back on line without further issue :mad2:. Most likely there is a loose wire or something. Regardless, it didn't work during the flight. By the way, my friend was able to get ground transport home......eventually. Thanks for the input.
Time to track EVERY wire before attributing this to moisture in the Voltage Regulator (even harder if you have a Zeftronics).

We all go through this. But you did good.
 
I had an unusual occurrence today flying my friend's C182 and thought I would seek some opinions. I was on an IFR flight plan, although the weather was CAVU and was about an hour and a half into a three hour flight when the alternator failed. Multiple attempts to get it back on line failed. I could easily have cancelled IFR and continued to my destination VFR without a problem. However, the airport I was going to was in the middle of Nowhere Kansas with limited/no services available. To continue, I had two primary concerns. #1 would I have enough battery to start the airplane for the return trip? #2 Would I have enough battery on the return leg to contact the tower for D airspace and landing clearance?

Since I had no idea how long the battery might last, even with everything shut down, I elected to return to my home airport (leaving my friend semi-stranded in the middle of Nowhere Kansas. The enroute center was nice enough to phone my friend and advise him that I had turned around). I continued to try getting the alternator back on line and my last attempt was on final approach at my home airport, with still no luck.

Here are my questions: #1. With a good battery and power usage minimized, how long could I reasonably expect the battery to last for necessary radio and transponder usage? (I would have been within the 30 mile veil of Class B upon return.) #2. Would you have continued the flight VFR or not?

Oh yeah, here's the kicker. After I landed I tried the alternator again and it came back on line without further issue :mad2:. Most likely there is a loose wire or something. Regardless, it didn't work during the flight. By the way, my friend was able to get ground transport home......eventually. Thanks for the input.

On alternator failure that doesn't reset I land as soon as possible. If it's a belt drive, I want to get the belt clear before it gets behind the crank flange and tears up the nose seal on a Lyc, or just pop it on/replace on a belt drive Continental. On a gear drive Continental I want to be on the ground quick, and if I'm in a twin, I'll feather that engine to stop it turning. If you loose the alternator due to a known problematic drive system you lunch an engine. *Ownership Tip* If this failure happens to you, you can typically get the insurance company to buy everything except the alternator and drive assembly. Since they are considered accessories rather than components they can serve as the failure origin and the crank and case 'proximate damage'.
 
Not to mention that on most single Cessna's the alternator is required equipment for airworthiness and when an aircraft no longer is "airworthy" the regs (91.7) say you should discontinue the flight. Now obviously this is at the pilot's judgment, as you shouldn't terminate the fight into the side of a mountain, but I'd be looking for a place to have some maintenance done.

Ryan
 
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...... The enroute center was nice enough to phone my friend and advise him that I had turned around). .......

Personally I would call the enroute center and thank them for their actions... It was beyond the call of duty but made your alternator failure and your friends position alot easier to get through.....

Cheers to the controllers.. :cheers:

Ben.
 
So you were planning to re-depart with a known deficiency.

If I determine that the deficiency does not pose an undue risk to the safety of flight then that factor alone would not keep me on the ground. The sad reality is that many places you may land to verify condition and solve or secure there is no maintenance available anymore. It's not like it was 20 years ago where every strip had someone working on planes. If I determine the situation to be secure and safe for continued flight, yes, I would continue with a known INOP alternator; I'm not spending thousands of extra dollars transporting mechanics.
 
BTDT and it was not fun.

The danger isn't really flying partial panel -- it's in the moments before you recognize and correctly diagnose what's happening in IMC.

The voltmeter idea is a very good one. I set the Garmin 496 to alert on low voltage. Could be a real life saver.
 
If I determine that the deficiency does not pose an undue risk to the safety of flight then that factor alone would not keep me on the ground.
Safety of flight alone is not the legal standard -- airworthiness is, and being in a safe condition for flight is only half of the airworthiness equation. Henning may choose otherwise, but before you follow his path, consider the consequences if it comes to the attention of the FAA. An enforcement action for deliberately choosing to fly an unairworthy aircraft is likely to result in a big suspension or even revocation. Also, if the end result involves injury to another or damage to another's property, the only question before the court will be how much you have to pay, not whether you have to pay (see "negligence per se" in any legal text).

The OP made a good decision to promptly discontinue the flight and get it fixed before proceeding. Good on ya! As for how long the battery would last, it's impossible to say. It all depends on the condition of the battery and how much electrical load remains after some vigorous load-shedding, but I wouldn't count on more than 30 minutes.
 
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If I determine that the deficiency does not pose an undue risk to the safety of flight then that factor alone would not keep me on the ground.
How do you determine that in the air? That's a toughie.
The sad reality is that many places you may land to verify condition and solve or secure there is no maintenance available anymore.
AMEN.
It's not like it was 20 years ago where every strip had someone working on planes. If I {can} (added by BC) determine the situation to be secure and safe for continued flight, yes, I would continue with a known INOP alternator; I'm not spending thousands of extra dollars transporting mechanics.
Like I said above.....(he says, with his Airmotive re-OH'd Kelly alternator sitting in the nose bay, the 414CC pump in there too).....

Intermittency-->wire? Belt? VR failure? Overvoltage relay?
In the twin I can shut one alternator down one system down and rely on the other to get to a service center, but even then I have all the belt assoc. problems of which you are note.

There is no substitute for getting down and having a look. For this sort of flying, "fly to failure" is a nonstarter.

And if I had a choice, (VFR, no ice, etc) I would choose my "get down" spots to be Des Moines, IA, Olathe KS, Lincoln NB, and if in the Western Plains ---> LBF because UPS flies in there 6 days/wk....but I'd have to be pretty sure I wasn't going to rip out a seal by letting the shaft keek turning. I would not want to have any ice at all, to make the additional leg to a service center. And I really really don't like limping along on one blower when a perfectly serviceable (for landing) runway is within 20 minutes.

It's still cheaper to leave it, and rent a car, than to risk major alternator drive troubles. Sigh.

PS Welcome back.
 
How do you determine that in the air? That's a toughie.AMEN. Like I said above.....(he says, with his Airmotive re-OH'd Kelly alternator sitting in the nose bay, the 414CC pump in there too).....

Intermittency-->wire? Belt? VR failure? Overvoltage relay?
In the twin I can shut one alternator down one system down and rely on the other to get to a service center, but even then I have all the belt assoc. problems of which you are note.

There is no substitute for getting down and having a look. For this sort of flying, "fly to failure" is a nonstarter.

And if I had a choice, (VFR, no ice, etc) I would choose my "get down" spots to be Des Moines, IA, Olathe KS, Lincoln NB, and if in the Western Plains ---> LBF because UPS flies in there 6 days/wk....but I'd have to be pretty sure I wasn't going to rip out a seal by letting the shaft keek turning. I would not want to have any ice at all, to make the additional leg to a service center. And I really really don't like limping along on one blower when a perfectly serviceable (for landing) runway is within 20 minutes.

It's still cheaper to leave it, and rent a car, than to risk major alternator drive troubles. Sigh.

PS Welcome back.

Note my previous response to the OP, First thing to do is land and determine the problem at the nearest safe spot or secure the engine in a twin if I have gear drive alternators. Once repaired or determined secure and safe. If I can secure it without being able to repair it, I'll take the risk; I don't follow rules written for idiots to the point of silliness, they can pull my ticket.

The problem with continuing even 20 minutes with gear drive alternators (especially the 520/550 with the alternator up front) can cost you a crank and cases and a whole lot more headache and cost.
 
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Note my previous response to the OP, First thing to do is land and determine the problem at the nearest safe spot or secure the engine in a twin if I have gear drive alternators. Once repaired or determined secure and safe. If I can secure it without being able to repair it, I'll take the risk; I don't follow rules written for idiots to the point of silliness, they can pull my ticket.

The problem with continuing even 20 minutes with gear drive alternators (especially the 520/550 with the alternator up front) can cost you a crank and cases and a whole lot more headache and cost.
Do yo think you'd have any difficulty getting a ferry permit for something like this so you could get it where you wanted the maintenance to be done? Would you even bother trying?
 
Do yo think you'd have any difficulty getting a ferry permit for something like this so you could get it where you wanted the maintenance to be done? Would you even bother trying?

If there's no A&P on the field then a ferry permit is a waste of time and effort, besides, they aren't available at 01:00. If a ferry permit with a signature is available, sure.
 
If there's no A&P on the field then a ferry permit is a waste of time and effort, besides, they aren't available at 01:00. If a ferry permit with a signature is available, sure.
I've never had occasion to request a ferry permit. For some reason I thought that simple ones could be gotten telephonically from the FSDO, though, of course, not at 0100. I conclude from this that they require an A&P's evaluation an maybe signature to obtain?
 
I've never had occasion to request a ferry permit. For some reason I thought that simple ones could be gotten telephonically from the FSDO, though, of course, not at 0100. I conclude from this that they require an A&P's evaluation an maybe signature to obtain?
Not "maybe" -- absolutely. A log entry signed by an A&P certifying the aircraft is safe to fly is required before you can fly on a Special Flight ("ferry") permit.
 
The problem with continuing even 20 minutes with gear drive alternators (especially the 520/550 with the alternator up front) can cost you a crank and cases and a whole lot more headache and cost.

Of course, it's good to know one's plane. In my case, the alternator drives have a clutch that will slip when the alternator fails. Not infallible, but I've lost more than one and it wasn't an issue. In the OP's case, I would have done what he did.

One also needs to know the plane's systems. I got an alternator out light once when departing Denver (twin) and I still departed. Because of the manner in which my alternators are wired that can happen with a good alternator and that's exactly what it was. When I took the good alternator off line, the other picked up the load even though the annunciator light showed it wasn't working. I didn't need an A&P to sign off on that.

I've only gotten one ferry permit and it wasn't fun. No A&P wants to sign one of those unless one really has a strong relationship. If all goes well, he gets little reward; if anything goes wrong, his neck is on the line. We let a plane get out of annual once--just mixed up the months--and had to get a permit to fly it to get the annual done. FSDO wouldn't allow it with out an A&P approval.

Best,

Dave
 
Not "maybe" -- absolutely. A log entry signed by an A&P certifying the aircraft is safe to fly is required before you can fly on a Special Flight ("ferry") permit.

I wouldn't sign a ferry permit in this case before I removed the alternator and placed a blank off plate on the hole.

If I were going to do that I rather fix the aircraft.
 
Not "maybe" -- absolutely. A log entry signed by an A&P certifying the aircraft is safe to fly is required before you can fly on a Special Flight ("ferry") permit.

I wouldn't sign a ferry permit in this case before I removed the alternator and placed a blank off plate on the hole.

If I were going to do that I rather fix the aircraft.
Thanks. There's book learning, then there's real world learning! For the private, it was always "contact the FSDO for the ferry permit."
 
Alternator on the older 182s is belt-driven. Ditto all the comments regarding the desire not to continue if that thing is flailing around up there.

As some have eluded to, moisture in the old can-style voltage regulators can cause havoc.

CPA recommends making sure they're good and dry and sealing the bottom of the can. They have a tech tip on it with photos.

Better solution someone else mentioned is to go to the solid state variety. They're very reliable. They're also already on a lot of the fleet since they're the commonly used replacement for an original failed one.

Often the thing that gives up first in the system with wild voltage spikes is the 50 amp breaker feeding the main buss.

Unless there's an airport immediately below, I'm not resetting a popped 50 amp breaker in-flight. If it failed for a real short circuit, that's a lot of current. Good way to start a fire. Especially if you have the non-pullable variety and can't turn it back off.

Someone mentioned setting their Garmin for a low-voltage warning. That's smart but maybe... not necessary in a mid-year 182. Belt and suspenders, perhaps.

Lots of folks don't realize that the High Voltage light on the panel actually comes on for High Voltage, Low Voltage or a non-energized field circuit in a properly working 182 voltage regulator. 3 ways to illuminate a poorly labeled light. It should just read "Electrical Malfunction" really.

The HV light can be tested by switching off the Alternator field circuit side of the split master switch at idle. Discharge on the Ammeter, HV light illuminated. That's all that half of the split master controls... the Alternator field wire. The other half controls the circuit that closes the battery relay. (High current doesn't flow through the split master switch at all.)

Other 182 electrical system gotchas include that the ground power plug bypasses the battery completely. People think they can charge or "jump start" a dead battery via the ground power plug. Nope. You'll hear a relay clunk and the battery side of the master becomes a switch for connecting ground power to the starter and avionics.

With no battery inline to act as a big capacitor, if you have an Avionics Master, make sure it's off during ground power starts until the plug is removed. Big spikes and/or dirty ground power is a dumb way to blow up an avionics stack.

And there's a diode in the ground power circuit that if it's failed, will immediately cause the starter to crank when you plug in ground power. Rare but a highly dangerous design problem.

The plug is WAY too close to the prop to utilize it safely unless you've fully briefed the person plugging in the ground power plug that the prop only a foot away *could* start turning the moment they turn the power on to the plug, or if they plug it in "hot", right then.

It's good to read your circuit diagrams and know them. The "sneak" circuit if that diode is failed has scared the crap out of more than one person using the 182 ground power port when the engine starts cranking without a key in the ignition switch. It can also lie in wait for years since the plug is rarely used.

Best to just remove the battery and recharge it somewhere well-ventilated anyway, if it's dead.
 
Thanks. There's book learning, then there's real world learning! For the private, it was always "contact the FSDO for the ferry permit."

The ferry permit can only be applied for by the owner, by phone or e-mail to the A&P's PMI. it can be fax'ed to you by FSDO.

But as Ron has pointed out, the aircraft must be inspected and the log book entry made certifying the aircraft is safe to make this flight.

Not many A&Ps want to do very permits because they earn money by repairing the aircraft.

plus the FSDO will not issue a ferry permit to any aircraft that can be repaired where it is. they do not care if you must get home on time.
 
One of our favored shops at our home base did a Ferry Permit for us to fly the aircraft across town to the usual shop for the Annual last year (or was that the year before? Time flies...)

But he'd just gotten through putting a new bladder tank in the left wing which is what umm... Somewhat delayed getting the aircraft across town before it turned into a pumpkin.

Both shops got plenty of $$$ that year. ;)
 
plus the FSDO will not issue a ferry permit to any aircraft that can be repaired where it is. they do not care if you must get home on time.

Not where I'm at. We don't care who or where the owner wants to have the maintenance performed. If the owner request a ferry permit, we send it and request the A&P sign it along with the logbook and they're good to go.
 
To the OP: You did it right.

Continuing another 4.5 hours without an operating alternator would be three things:
1. Stupid
2. Stupid
3. Stupid
Guess who the NTSB report of the smoking hole you left would assign the blame?
Guess who's family would sue your wife?
And did you actually have daylight left for another 4.5 hours plus turn around on the other end? (rhetorical question - answer not required)

Remember the physics equation you should have learned in ground school:
Bold Pilot /= Old Pilot

denny-o
 
ref SFP's - I notice my insurer now requires preapproval for such flights, I bet mine is not the only one.
 
Personally I would call the enroute center and thank them for their actions... It was beyond the call of duty but made your alternator failure and your friends position alot easier to get through.....

Cheers to the controllers.. :cheers:

Ben.

Yes, it was nice for them to do that, but really still part of the job (service). I was an FAA controller for over 30 years and this type of thing used to be just a normal part of the job. I still appreciate him making the call and thanked him accordingly.
 
Oh yeah, here's the kicker. After I landed I tried the alternator again and it came back on line without further issue :mad2:. Most likely there is a loose wire or something. Regardless, it didn't work during the flight. By the way, my friend was able to get ground transport home......eventually. Thanks for the input.

If you get a momentary over voltage, the alternator will go off line. To restart the alternator, you have to reset the over voltage relay. Tell ATC you have an alternator problem and that you will be off line for a minute or so to see if you can reset it. Then turn off the avionics master, then both sides of the split battery alternator switch, then both back on. Hopefully the alternator will come back on as this is likely what happened after you shut down. A very low battery voltage will also have the effect of resetting the over voltage relay once the voltage drops enough as you drain the battery down. I used to own a flight school and it was not uncommon for the over-voltage to kick the alternator off immediately after starting the engine. This was rarely noticed by the customer until the radios started to fade, usually after a half hour or less. This can be part of the runup check list. Ideally with a voltmeter, but if one isn't available, turn on a high load such as a landing light and the alternator should pick up the slack. If it shows a continuous discharge, use the procedure described above.
 
To the OP: You did it right.

Continuing another 4.5 hours without an operating alternator would be three things:
1. Stupid
2. Stupid
3. Stupid
Guess who the NTSB report of the smoking hole you left would assign the blame?
Guess who's family would sue your wife?
And did you actually have daylight left for another 4.5 hours plus turn around on the other end? (rhetorical question - answer not required)

Remember the physics equation you should have learned in ground school:
Bold Pilot /= Old Pilot

denny-o

Whoa there cowboy! Maybe you failed to note a few things here. First, severe VFR. Second, and I might be mistaken here, for VFR flight I don't know of anything that makes the alternator a required piece of equipment. Lord knows there are lots of airplanes flying without electrical system. Third, why in the world would a failed alternator lead to a "smoking hole in the ground"? Fourth, screw the lawyers. Fifth, yes there was plenty of daylight. Sixth, I did turn around and head for home so hopefully in your eyes I wasn't "stupid, stupid, stupid."
 
I was on an IFR flight plan, although the weather was CAVU and was about an hour and a half into a three hour flight when the alternator failed.

Continuing another 4.5 hours without an operating alternator would be

I understood that he was 1/2 way to his destination when he turned around. He didn't know if maintenance was available at the destination, but knew there was at home. For that reason, I agree with the decision. He also reasoned that it's better to "strand" 1 person than 2+ an airplane.

Safety of flight alone is not the legal standard -- airworthiness is, and being in a safe condition for flight is only half of the airworthiness equation. Henning may choose otherwise, but before you follow his path, consider the consequences if it comes to the attention of the FAA. An enforcement action for deliberately choosing to fly an unairworthy aircraft is likely to result in a big suspension or even revocation. Also, if the end result involves injury to another or damage to another's property, the only question before the court will be how much you have to pay, not whether you have to pay (see "negligence per se" in any legal text).

While on the ground the pilot can pull the cowling and look for the mechanical failure suspected as mentioned in several posts. I agree that it would be irresponsible to fly with a belt flailing around the cowling, but if it's a regulator or some other component that would not start a fire, I have to agree with Henning. Besides, as I said above, he has as much risk continuing to destination as going back home, being 1/2 way through the flight.
 
On alternator failure that doesn't reset I land as soon as possible. If it's a belt drive, I want to get the belt clear before it gets behind the crank flange and tears up the nose seal on a Lyc, or just pop it on/replace on a belt drive Continental. On a gear drive Continental I want to be on the ground quick, and if I'm in a twin, I'll feather that engine to stop it turning. If you loose the alternator due to a known problematic drive system you lunch an engine. *Ownership Tip* If this failure happens to you, you can typically get the insurance company to buy everything except the alternator and drive assembly. Since they are considered accessories rather than components they can serve as the failure origin and the crank and case 'proximate damage'.

What provision of an insurance policy would cover engine damage caused by an alternator failure?
 
Not where I'm at. We don't care who or where the owner wants to have the maintenance performed. If the owner request a ferry permit, we send it and request the A&P sign it along with the logbook and they're good to go.

If that is the attitude where you are, then just give each A&P a few copies and let them issue the permits.

I get asked every time "why can't the aircraft be repaired where it is".
 
An aside on the alternator reset...sometimes you just need to wait a couple of minutes before resetting the master switch, if you try and reset it immediately, it usually will not stay back online. It came back online when you landed either due to a loose connection reconnected, as you stated, or the thermal protection in the master had cooled down enough to allow the reset to stay online. I don't recall if you mentioned whether or not the alt or field breakers popped?

As for entering the class D...well just before you go in, turn on the comms, and announce your position, intent and situation to the controller, get expedited handling to land, and you're golden. BTDT They may ask you to leave a 7600 code in the transponder, and then shut down all the nav-comms so you can be tracked inbound.
 
If that is the attitude where you are, then just give each A&P a few copies and let them issue the permits.

Are you advocating the government tell an owner where and who will repair his aircraft? Personally I feel that's up to the owner, as it should be.

On a related note, now many commercial operators (135/121) actually carry ferry permits onboard the aircraft and have a blanket approval to use them as required.


I get asked every time "why can't the aircraft be repaired where it is".

Just ask them back to please show in guidance where they are required to have repairs made at a particular facility. ;)
 
If you get a momentary over voltage, the alternator will go off line. To restart the alternator, you have to reset the over voltage relay. Tell ATC you have an alternator problem and that you will be off line for a minute or so to see if you can reset it. Then turn off the avionics master, then both sides of the split battery alternator switch, then both back on. Hopefully the alternator will come back on as this is likely what happened after you shut down. A very low battery voltage will also have the effect of resetting the over voltage relay once the voltage drops enough as you drain the battery down.

Thanks, but I think if you read my original post, that is exactly what I did....multiple times. The alternator would not come back online, ATC was advised, and I returned to my home base. Since I was flying into 45 knot headwinds, the trip home was a lot shorter.
 
What provision of an insurance policy would cover engine damage caused by an alternator failure?

Because the engines are part of the aircraft and are insured. The only part that is not insured in a failure related claim is the initial point of failure; that you are responsible for as a normal wear and tear issue. Since the alternator is considered an accessory to the engine rather than a component of the engine assembly, damage caused to the engine by a failure of the alternator is covered.
 
An aside on the alternator reset...sometimes you just need to wait a couple of minutes before resetting the master switch, if you try and reset it immediately, it usually will not stay back online. It came back online when you landed either due to a loose connection reconnected, as you stated, or the thermal protection in the master had cooled down enough to allow the reset to stay online. I don't recall if you mentioned whether or not the alt or field breakers popped?

As for entering the class D...well just before you go in, turn on the comms, and announce your position, intent and situation to the controller, get expedited handling to land, and you're golden. BTDT They may ask you to leave a 7600 code in the transponder, and then shut down all the nav-comms so you can be tracked inbound.

Yes, after the first few attempts to get it back on line I waited 10 minutes or so with everything shut down before I tried again. No luck. I cancelled IFR, shut everything down and only turned the transponder and radio back on when I needed it for the Class B. The only time 7600 would be appropriate was if I had been receiving radar service and had lost my radio. I had not. It was all pretty much a non event. I'm still waiting for someone to tell me how long I could expect a good battery to last while operating radio and transponder. Thanks for your input.
 
Define "good battery".... If the battery is new but has a small amp hour capacity then you can expect a given time frame for running the comm and transponder.... If the battery has a rather large amp hour rating then you can maintain a longer "in contact" time... IMHO.

ben.
 
An aside on the alternator reset...sometimes you just need to wait a couple of minutes before resetting the master switch, if you try and reset it immediately, it usually will not stay back online. It came back online when you landed either due to a loose connection reconnected, as you stated, or the thermal protection in the master had cooled down enough to allow the reset to stay online. I don't recall if you mentioned whether or not the alt or field breakers popped?

There is no thermal protection in the master switch. The breakers are usually thermal devices and need a bit of cooldown time, especially the larger sizes. The alternator output breaker is an example of that; the alternator field breaker does nothing but power the tiny relay in the regulator; the field current itself comes from the alternator's "A" terminal which is also connected to the bus via the output breaker.

Tripping offline for no good reason is often due to a bad ground connection for the overvolt sensor. It loses its reference and goes nuts and shuts off the regulator. If the field breaker is old its contacts might be corroded or oxidized and it will also trip the system offline. Old airplanes (like 1970s) are famous for oxidized breakers. Newer airplanes often have electronic regulators with the overvolt sensor built in, and those things are hypersensitive to stray RF that leaks into the aircraft's wiring via a corroded or loose Comm antenna cable connection. The cable shielding can't control the leakage if it has a dirty bayonet. Commonly found in the ceiling at the antenna itself, where condensation collects on the inside of the skin.


That said, most alternator hassles are due to worn field brushes. A 500-hour inspection catches that before it's a problem, and alternator failures become almost unknown.

Dan
 
Thanks. There's book learning, then there's real world learning! For the private, it was always "contact the FSDO for the ferry permit."
That's a good answer in that context, but realize that the first thing they'll ask is if you got an A&P to sign a "safe for flight" entry in the logbook.
 
I understood that he was 1/2 way to his destination when he turned around. He didn't know if maintenance was available at the destination, but knew there was at home. For that reason, I agree with the decision. He also reasoned that it's better to "strand" 1 person than 2+ an airplane.
The FAA has fried pilots for not landing at the first suitable airport when an unairworthy condition occurs in flight -- without regard for convenience.
...we have interpreted section 91.7(b) as requiring -- upon the occurrence of an unairworthy condition -- a landing "at the first available point consistent with the safe operation of that aircraft." Administrator v. Genereaux, 4 NTSB 1245, 1247 (1984), (quoting the law judge's initial decision); Administrator v. Halbert, NTSB Order No. EA-3628 at 5 (1992).
While on the ground the pilot can pull the cowling and look for the mechanical failure suspected as mentioned in several posts. I agree that it would be irresponsible to fly with a belt flailing around the cowling, but if it's a regulator or some other component that would not start a fire, I have to agree with Henning. Besides, as I said above, he has as much risk continuing to destination as going back home, being 1/2 way through the flight.
One more time -- the fact that you think it's safe to operate the aircraft does not change the fact that it is legally unairworthy on the basis of not being in conformance with its type certificate and having an unrepaired problem.

I've been reading Henning's posts for years, and he has an extremely high risk tolerance, especially when it comes to the rules. Don't take his advice on this matter unless you don't mind losing your pilot certificate if caught doing what he suggests.
 
Are you advocating the government tell an owner where and who will repair his aircraft? Personally I feel that's up to the owner, as it should be.
I've never heard of a FSDO refusing a ferry permit solely on the grounds that the aircraft could be repaired in situ.

OTOH, I have seen FSDO Airworthiness personnel refuse to sign off on a ferry permit even after the A&P signed it as "safe for flight" until the congnizant Aircraft Certification Office was consulted to convince the Inspector involved that it was OK to fly the plane in its existing condition. The case in point was a leaky fuel tank on a Grumman Traveler, and despite the lack of any lateral fuel imbalance restrictions in the POH or TCDS, the local Inspector said that unless we could prove it was safe to fly with one tank full and the leaky tank empty, we couldn't have the permit. Eventually, the ACO told the Inspector it really was legal to fly an AA-5 with one tank full and the other empty, but it delayed the ferry 24 hours which added to the owner's expenses.
 
The FAA has fried pilots for not landing at the first suitable airport when an unairworthy condition occurs in flight -- without regard for convenience.
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what's airworthy? What's safe to fly? Who's decision is that ? 91.3

In this case, is the failure of an alternators an emergency?
 
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