Bad battery?

We don’t plan on the battery lasting more than 3 years. Regular summer temperatures well into the 100teens.
 
Aircraft batteries should never be jumped. You need 30 minutes of reserve power for avionics if the alternator gives out. You've gotten all the life you probably can from that battery.
 
Never get jumped? You must have never been stranded with a dead battery. How about hand-propping? Is that a bad idea, too? I've done both more than once.
 
Stewartb said:
Never get jumped? You must have never been stranded with a dead battery. How about hand-propping? Is that a bad idea, too? I've done both more than once.
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If you're stuck out somewhere then of course. But I've seen too many guys milk a near dead battery on their own Field for many months. If battery's strong and was drained due to some accessory left on, charging is a good idea. I just think it's unsafe to fly without any reserve power on board to run the avionics should the alternator fail.
 
Starting an engine requires a lot of power. Running radios on a low-ish battery is not a big deal. Running pitot heat and old-school incandescent lights? That's a battery killer. Turn off the lights and run the radios. They'll probably outlast the fuel duration.
 
A friend lent his 140 to a another friend who left the master on (not sure how long), which killed the battery. They jump started it and the friend immediately turned everything on. The field CB popped; he pushed it back in and something else popped. No juice. After flying it home with no power, we discovered the 40 amp breaker had blown apart, due to the excessive load of trying to charge a completely dead battery. The battery was slow charged over night with an appropriate charger (not cheap either) and it is still fine.

Had they used the jumpers to charge the battery for 30 or so minutes, all would have been fine. I agree with others that you only jump start in an emergency situation and try not to put yourself in that situation by attempting to extend the life of an old battery.

Desulfating chargers are the only way to get more life from your battery. Hook it up at annual and let it do its thing.

If/when EarthX every gets an STC for their batteries, drop one in, get more cranking amps, longer life and save 15-20 lbs.
 
We had a battery on our field explode when jump started in a plane. The local flight school had large picture of that battery on display as a lesson to students regarding the risks of jump starting.

Most new avionics also stop working when the voltage is ~4 volts lower then specified. The notion that a 430 will out run the fuel tanks on a low non-charging is a myth.

The current NALL report states 74% of aviation accidents are pilot error. Departing with a battery in sufficient charge to last 30 minutes is adding unnecessary risk. Pilots are welcome to take the chances they want to take, but for me deferring an eventual $350 battery purchase is not worth it.
 
I'd always wondered what happens when a battery is completely discharching.

disch-600x563.png
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NordicDave said:
We had a battery on our field explode when jump started in a plane. The local flight school had large picture of that battery on display as a lesson to students regarding the risks of jump starting.

Most new avionics also stop working when the voltage is ~4 volts lower then specified. The notion that a 430 will out run the fuel tanks on a low non-charging is a myth.

The current NALL report states 74% of aviation accidents are pilot error. Departing with a battery in sufficient charge to last 30 minutes is adding unnecessary risk. Pilots are welcome to take the chances they want to take, but for me deferring an eventual $350 battery purchase is not worth it.
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A dead starting battery is usually defined as 12.0v or lower. A typical size starting battery at 12.0 won’t spin your engine to start but it’ll run electronics for a long time. That’s a pirep from my couple of years with an intermittent charging system. Even with a little Odyssey battery my radios never failed me.
 
DesertNomad said:
Update... it started fine, had good readings on the ammeter and volt meter. New battery being ordered.
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Why? Suppose, just suppose when you shut it down you had it 90% of the way up on the compression stroke. You've got what? Maybe 150-160 psi on a 5" piston. And maybe the battery is getting just a little bit old. But next morning when it started just fine that cylinder had leaked down overnight to zero psi. Sure it started fine. Next time it happens, pull the prop through WITH THE MIXTURE PULLED AND THE MAGS ABSOLUTELY OFF through about two or three compression strokes. THEN try and start it. You are probably spending money on a battery that has a year or two left in it.

Jim
 
NordicDave said:
Aircraft batteries should never be jumped. You need 30 minutes of reserve power for avionics if the alternator gives out. You've gotten all the life you probably can from that battery.
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From a pure regulatory stand point, you are bang on.

From a practical one, jumping and hand propping happens all the time. As long as the fan is running and the magenta line is there, pilots are happy. "Get the mission done". And when it comes to getting out of isolated areas, why not. But it gets used way too often flying from big centers, in flight schools, etc.
 
The Concorde battery maintenance manual has a very nice description of how to do a capacity test and if it fails that, how to do a conditioning charge, and then run another capacity test, then if it fails it's time for a replacement. http://www.concordebattery.com/main_air_tech.php

I need to test mine as it's acting a little suspect, I have the gear for the conditioning charge, but I'm going to have to fudge the capacity test a bit as I don't have anything that can do a constant C1 discharge, but I do have an integrating meter that can measure the capacity if I can get it close enough with a resistive load.
 
It did it again today, but managed to start. It had flown 2 hours and had been shut down for 20min. I knocked out my CPL Solo XC today.

The plane is in annual now so they'll figure it out. Could be the starter.
 
DesertNomad said:
It did it again today, but managed to start. It had flown 2 hours and had been shut down for 20min. I knocked out my CPL Solo XC today.

The plane is in annual now so they'll figure it out. Could be the starter.
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Next they'll replace the starter. Then it will do it again and they'll finally check those old master and starter contactors.
 
Dan Thomas said:
Next they'll replace the starter. Then it will do it again and they'll finally check those old master and starter contactors.
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1 or two annuals ago they replaced the old (aluminum?) starter cable with copper so while that could be it, it seems unlikely.
 
Cables aren't contactors. The contactors (solenoids) are mostly ignored or overlooked when troubleshooting. They are big switches, and most of us know that switches get old and wear out. Yet we'll replace stuff---spend money---instead of taking a few measurements.
 
Dan Thomas said:
Cables aren't contactors. The contactors (solenoids) are mostly ignored or overlooked when troubleshooting. They are big switches, and most of us know that switches get old and wear out. Yet we'll replace stuff---spend money---instead of taking a few measurements.
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You are right on the button. I detest mechanics that take the shotgun approach to troubleshooting.

JIm
 
Hey guys, I thought I'd ask here so I would not start yet another topic. I am a student pilot, flying 172. I was pre-flying it and let the master on (I know, I know...). Gas truck came to top it off and I stepped out (with master still on). When I came back and try to start it it would not even crank. The battery was dead. All together master was on for about 30 min. We tried to charge the battery but it did not work (while charging amps would go to 28, but as soon it was out it would go down to 19 or so). I wonder if this 30 min could kill the battery, what are your thoughts?
 
weirdjim said:
You are right on the button. I detest mechanics that take the shotgun approach to troubleshooting.

JIm
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The ability to accurately diagnose is what makes a good mechanic. For cars, aircraft or really any mechanical device.
 
beretta said:
Hey guys, I thought I'd ask here so I would not start yet another topic. I am a student pilot, flying 172. I was pre-flying it and let the master on (I know, I know...). Gas truck came to top it off and I stepped out (with master still on). When I came back and try to start it it would not even crank. The battery was dead. All together master was on for about 30 min. We tried to charge the battery but it did not work (while charging amps would go to 28, but as soon it was out it would go down to 19 or so). I wonder if this 30 min could kill the battery, what are your thoughts?
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Unless everything in the plane was left on, 30 minutes should not kill a serviceable battery. With all the radios turned off, pretty much all you are running is the electric gyros and maybe some engine gauges, only a few amps. If you left the whole avionics stack on, and the flashing beacon, maybe. To properly charge a flat battery will take many hours.
 
chemgeek said:
Unless everything in the plane was left on, 30 minutes should not kill a serviceable battery. With all the radios turned off, pretty much all you are running is the electric gyros and maybe some engine gauges, only a few amps. If you left the whole avionics stack on, and the flashing beacon, maybe. To properly charge a flat battery will take many hours.
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Thank you, makes sense. I left lights and pitoh heat on, beacon was not working :(
 
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