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Posted
1 hour ago, Hank said:

I have a gas-powered golf cart, but out in the country, it's not going on any trips. I fill it with avgas, just because car gas goes bad so fast. I probably use ~5 gallons annually,  so the additional cost and trouble are negligible. It usually takes just a couple of minutes to fill up in the driveway. 

I had some extra avgas a long time ago and ended up using it in a lawn mower.  I enjoyed the smell of the burning avgas much more than I expected.  Just something about that smell! 

  • Like 1
Posted
1 hour ago, Utah20Gflyer said:

I had some extra avgas a long time ago and ended up using it in a lawn mower.  I enjoyed the smell of the burning avgas much more than I expected.  Just something about that smell! 

Yea that’s the lead in it. 

Posted

@EarthX Inc I once had a well-intentioned FBO hook up a 24v jump cart to my 12v lead acid battery.  This caused my ancient technology battery to explode, spraying acid all over the inside of the battery box, which then dripped out the drain onto the tarmac.  It fried the master, starter, and aux power solenoids, the starter, the left mag, and the slick start module in the plane. It cost several thousand dollars to fix, and interrupted a family trip, costing several thousand more dollars in airfare.  I was fortunate it didn't also fry anything in my panel, since I had newer avionics that are 12/24v.  I've heard this event (which has happened to others, and I'm sure will happen to others in the future) has destroyed entire panels before.

What would have happened if I'd had an EarthX battery with a built-in battery management system?  Looking at your destruction video, it looks like yours has overcharge protection built in.

Posted
14 hours ago, Shadrach said:

 It’s easy to say that less capacity is adequate on the ground. 

Hi Ross,

Just a clarifying note, the 161 tests over the 5 years take into consideration every conceivable test/scenario you can imagine..... and then more. About the only "ground" test is to start the plane. 

Posted
1 hour ago, EarthX Inc said:

Hi Ross,

Just a clarifying note, the 161 tests over the 5 years take into consideration every conceivable test/scenario you can imagine..... and then more. About the only "ground" test is to start the plane. 

My comment had nothing to do with ground testing. It was simply my observation that what is sufficient in theory is not always sufficient in practice.

Let’s talk testing. Perhaps you can add some perspective. What number was used for average draw of a GA single in cruise.

I suffered charging system failure that resulted in lost comms before I was able to land. This was at least 20 years ago and I admit that I did not catch the failure right away (plane is better instrumented now) but I was only ~1.2hrs into the flight when the comms failed. I had about .5 hours of coms after I noticed the failure and shut down all non essential electronics. That was supposed to be a 23Ah battery.  I landed at Allentown NORDO at dusk. Grateful that my gear are not electric.  

I want to understand worst and best case scenarios. 

 

Posted (edited)
8 hours ago, Z W said:

What would have happened if I'd had an EarthX battery with a built-in battery management system?  Looking at your destruction video, it looks like yours has overcharge protection built in.

Hi Z W,

Sorry to hear that happened to you!  

EarthX does have built in protection for many different "abuses" that can happen with a battery and over voltage is one of them. (This is why Cirrus coined the phrase that is it a "smart" battery). :)  But to answer your question, nothing would have happened to the battery if a FBO used a 24V jump pack on your 12V battery as it protects itself from such an event. However, your other equipment that is 12V would have still been damaged. 

Part of the built in protection features is the battery has a local LED light indicator and it is also remotely mounted on your panel as the battery can annunciate to you with different flashing codes if something is outside of normal and should be investigated. Here is a link to a quick reference on what is being monitored: https://earthxbatteries.com/wp-content/uploads/2023/01/220707-LED-Indicator-Quick-Reference.pdf

It has been said that lead acid batteries do not need anything like this and the built in electronics is something to worry about failing, but as you experienced firsthand, protection would be a welcomed feature if it was possible, but acid does not play well with others, and it is not possible to have built in protection. 

Edited by EarthX Inc
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Posted
2 hours ago, EarthX Inc said:

EarthX does have built in protection for many different "abuses" that can happen with a battery and over voltage is one of them. (This is why Cirrus coined the phrase that is it a "smart" battery). :)  But to answer your question, nothing would have happened if a FBO used a 24V jump pack on your 12V battery as it protects itself from such an event. Your plane and battery would have been fine.

@EarthX Inc

I am curious how your BMS protects the PLANE in the event of an overvoltage due to hooking up 24V to a 12V system.  I can certainly see the BMS protecting the battery but please explain how the plane's other equipment is protected.

Posted
19 hours ago, Will.iam said:

 Same thing happened with manual compared to automatic transmission systems. At first a manual system were faster and more fuel efficient but the double clutch systems soon where able to shift faster than any human could manually and by designing 8, 10 and even 12 gears into the automatic they are now more efficient than the manual system too. They only advantage left in having the manual is the overhaul is much cheaper than the automatics. 

Not a great analogy.  The DCT for racing are typically not an automatic transmission with planetary gears.  They are more similar to a manual transmission that is automatically shifted by the electronics and hydraulics.

I have a 2002 BMW M3 SMG.  One of the early systems to shift the transmission.  In that case, the transmission is EXACTLY the same one as in the manual version.  As is the clutch/pressure plate/flywheel.  They just added the hydraulics and intelligence to shift it.  It is capable of doing an upshift in 80 ms.

Later version improved the system by ordering the gears for better performance, but in such a way, it could not be manually shifted in the proper order.

DCT is basically two manual transmissions with two clutches.  When you shift, the second transmission already has the proper gear selected, so are you are doing is disengaging one clutch and engaging the other.

Posted

I would love a lithium battery in my plane.

But again, I am concerned about the lower capacity.  And while the lower weight is good, there is the issue of having an aft mounted battery means my CG shifts forward.  And that can lead to being at or beyond the forward limit as well as the lower speed due to the forward CG.

A battery of 50% more or double the capacity and weight would sway my decision.

  • Like 1
Posted
1 hour ago, MikeOH said:

@EarthX Inc

I am curious how your BMS protects the PLANE in the event of an overvoltage due to hooking up 24V to a 12V system.  I can certainly see the BMS protecting the battery but please explain how the plane's other equipment is protected.

Hi Mike,

I apologize, I focused on the part of the post that said "spraying acid all over the inside of the battery box, which then dripped out the drain onto the tarmac" as that clearly would not happen to the plane if it was a lithium battery.  In the scenario of someone using a 24V jump on a 12V battery, the BMS protects the battery only, the BMS does not protect the other equipment on the plane. 

  • Thanks 1
Posted
2 hours ago, Pinecone said:

 there is the issue of having an aft mounted battery means my CG shifts forward.  And that can lead to being at or beyond the forward limit as well as the lower speed due to the forward CG.

 

Hi Pinecone, just an FYI, I have a M20K with the ETX900-TSO installed and it did change our CG forward 1/2 inch. We use the storage shelf above the battery to hold our spare oil and tools now.  

  • Like 1
Posted
4 hours ago, Shadrach said:

I suffered charging system failure that resulted in lost comms before I was able to land. This was at least 20 years ago and I admit that I did not catch the failure right away (plane is better instrumented now) but I was only ~1.2hrs into the flight when the comms failed. I had about .5 hours of coms after I noticed the failure and shut down all non essential electronics. That was supposed to be a 23Ah battery.

 

Hi Ross,

I totally get what you're saying and your concerns after having something like this happen to you and having a lower capacity battery makes you uncomfortable, whether it meets requirements or not.  I get it. 

The EarthX battery is designed with purpose and intent.  We did not design the battery to have double the capacity for a reason. The more capacity, the more cranking power, the more cost. It would have way too much cranking power for your system at around 760CCA.  The 15.6 Ah did exceed what has been determined as the safe capacity for a pilot who follows their POH and engineered to have a 150% margin with nighttime flying IFR conditions.  

The capacity testing requirements are performed to ASTM F2490-20 for electrical load shedding from cruise to emergency conditions if you find yourself in flight without an alternator. It does assume the pilot follows procedures in their POH and begin shedding their load. 

If you have critical equipment, you must have a backup power source. 

In the event of an alternator failure, there are many ways your plane alerts you to this situation and this can be different depending on the equipment you have installed. The ETX900-TSO also has a required LED to be installed on your panel and alerts you with a flashing LED light when you have drained the battery to 70% of its capacity.  

All certified products are tested to what is not only sufficient in practice, but also built in margins of error.  They are not designed to theory.

 

 

 

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Posted

For those concerned about battery backup capacity for running electronics what about a battery pack you could plug into your cigarette lighter to back feed power into the system?   I don’t think this would require any approval or certification and would offer cheap capacity.  
 

I built a power box for ice fishing that would work.  It’s a small plastic ammo can that I can put two 6.5 AH 40v  lawn mower batteries into and is converted to 40ah @12v.  
 

If anyone is interested in seeing it let me know and I’ll post a picture.  It’s a nice set up.  I actually used to power my icy breeze cooler with it but then I made a set up where I just slide the battery directly into a battery dock on the cooler and it powers it directly - less wiring that way.  
 

I don’t think I’d need something like that unless I was doing something crazy like crossing the Atlantic.  But a good thought exercise.  

Posted
22 hours ago, EricJ said:

Yup.   I used to do those demonstrations for a driving school I was involved with and it wasn't hard to teach the students how to out-brake the ABS, and it was a big confidence builder for them to learn it (this was for teenagers, some of whom had little driving experience).    The table started turning at least a decade ago when the factory ABS systems just got a lot better.   I was demonstrating the difference (attempting to, anyway) in a pretty new Mercedes GLK, and slammed on the pedal to get deep into the ABS and it just stopped, very quickly, with no drama whatsoever, in a very short distance.   For the first time I thought, I'm not going to be able to out-brake that.    I'd been warned by friends who were test drivers at some of the factory tracks around here that the new ABS systems were the shizzle, but that was the first time I'd actually enountered it.

Even with the older systems many racers (like me) kept the ABS just to keep from flat-spotting expensive tires.   If you weren't screwing up it didn't get in the way, and if you were it saved you a ton of money.

When I was in A&P school we had a Lear 23 that had a Goodyear analog electronic ABS system that was being put on certified airplanes in 1963.   I got to take that all apart, including the computer, and see how it worked, and it was brilliant in its functional simplicity.   Airplanes have had ABS for a long time, but it had a slightly different job than it does in cars.

Eric,

I always wondered about this even years ago. Year was 1995ish and a car show on a TV tested Mitsubishi Eclipse turbo that year ago I considered buying; bought a  Ford Probe GT, also with ABS.

Anyway, they demonstrated the ABS capabilities and driver was Emerson Fittipaldi. Test was not braking in line but with changing lanes, in a wet. ABS won!!

It was pretty impressive, IIRC and it wasn't advertisement for the car. No idea how my car would compare but I liked it better anyway.

Some years later I was telling this to a friend racer who thought for S. Barber and J. Bell and he was somewhat skeptical. He was saying they demonstrated regularly that drivers could outperform ABS but then they were not all equal anyway.

I always loved Emmo form his McLaren days and in my book if he couldn't outperform ABS, I certainly couldn't. :) 

 

Posted
24 minutes ago, Igor_U said:

Eric,

I always wondered about this even years ago. Year was 1995ish and a car show on a TV tested Mitsubishi Eclipse turbo that year ago I considered buying; bought a  Ford Probe GT, also with ABS.

Anyway, they demonstrated the ABS capabilities and driver was Emerson Fittipaldi. Test was not braking in line but with changing lanes, in a wet. ABS won!!

It was pretty impressive, IIRC and it wasn't advertisement for the car. No idea how my car would compare but I liked it better anyway.

Some years later I was telling this to a friend racer who thought for S. Barber and J. Bell and he was somewhat skeptical. He was saying they demonstrated regularly that drivers could outperform ABS but then they were not all equal anyway.

I always loved Emmo form his McLaren days and in my book if he couldn't outperform ABS, I certainly couldn't. :) 

 

The early ABS systems were mainly there to prevent loss of control due to lockup in the steering wheels.   So even if braking distance was increased, it was considered a success just to keep the front wheels turning so they could steer, and the rears from locking and causing a skid/spin.   From that standpoint they weren't optimized for performance, just for maintenance of control, which simplified the sensors and actuators since they could be a bit more crude and still work.   They worked mosty by fully releasing an individual locked-up brake just long enough to get the wheel turning again, and then allow re-application of brake pressure once the wheel was turning.   In some systems this results in some fairly violent vibrations in the brake pedal, but it worked.    It was also fairly inefficient from the perspective of optimizing grip, since it functioned by fully releasing the brakes momentarily, which does restore control, but doesn't help slow you down.

It isn't too hard to teach how to sense impending lockup in a tire, both from the sound and feel of what the tires are doing.   Very good drivers learn to be aware of what each tire is doing individually, and how to manage grip in each by management of the steering wheel, brake pedal, and sometimes throttle.   If you got even reasonably good at it, you'd be better than the older ABS systems which fully released the brakes periodically to keep the wheels turning.   In other words, it sounded gnarly to say you could out-brake or out-perform ABS, but it was mostly just possible because the ABS systems just weren't optimized for performance, just maintenance of control.   

The newer systems just evolved to do it better and started optimizing for broader performance, enabled by better sensors and actuators and more computer processing power, and man, they've gotten good.   It's been cool to see the evolution of the systems and the benefits they bring.

Posted
1 hour ago, EarthX Inc said:

We did not design the battery to have double the capacity for a reason. The more capacity, the more cranking power, the more cost. It would have way too much cranking power for your system at around 760CCA.  The 15.6 Ah did exceed what has been determined as the safe capacity for a pilot who follows their POH and engineered to have a 150% margin with nighttime flying IFR conditions.  

Thank you for taking the time to explain in detail. I am warming to the idea. In truth, I’ve spent most of my flying days not having much confidence that any aviation battery would function for long as a reliable backup. I am on my second Concorde AGM and they have been far better than the Gill G35s I used up until 10 years ago. When this one is due for replacement, I will consider an EarthX. Look forward to pireps from those who’ve already switched.

Posted
4 minutes ago, Shadrach said:

Thank you for taking the time to explain in detail. I am warming to the idea. In truth, I’ve spent most of my flying days not having much confidence that any aviation battery would function for long as a reliable backup. I am on my second Concorde AGM and they have been far better than the Gill G35s I used up until 10 years ago. When this one is due for replacement, I will consider an EarthX. Look forward to pireps from those who’ve already switched.

Curious as to your reasoning.  Is it that you believe that the Concorde only really has 1/2 its stated 33Ahr capacity, or that you really don't need that much time; i.e. half the capacity/half the time is sufficient for your needs?

Posted
On 1/25/2024 at 8:19 PM, Utah20Gflyer said:

Granted 20 lbs isn’t a huge gain but if you get a lightweight starter, switch to electronic instruments, remove the vacuum system, etc you can start making a significant difference in useful load.  As a general principle I try to strip weight out of the plane whenever possible.  I’m up 26 lbs so far, another 20 would be a big jump.  
 

The G model has the lowest gross weight of all the Mooneys other than maybe A models (50 lbs lower than a C).  If someone has an F with over 1k GW I get that they are unlikely to care about 20 pounds but I’m trying to get my gross to over 900 lbs.  I started at 849 lbs.  to each their own though.  

I’m a fan of lighter weight planes but I don’t skimp on batteries, starters, alternators, or magnetos.  Compromise elsewhere. 

  • Like 2
Posted
14 hours ago, MikeOH said:

Curious as to your reasoning.  Is it that you believe that the Concorde only really has 1/2 its stated 33Ahr capacity, or that you really don't need that much time; i.e. half the capacity/half the time is sufficient for your needs?

My reasoning is that my airplane’s electrical needs are trending downward and that I have had a single charging system failure in the last 20 years.  If the EarthX offers an honest 1 hr of operation, the delta between that and my RG35 is what, 15-20 mins at best?  In exchange 24lbs of UL. It’s worth considering.  I still think a dual battery with a switch would be ideal
 

 

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Posted

@Shadrach

Is your RG35 rated at less than 33Ahr; I'm struggling to understand how twice the capacity yields you only an additional 15-20 mins?  I'd think if EarthX's 15.6 Ahr gives 1 hour then 33 Ahr would give you at least 2 hours.

The two battery solution with switchover does sound appealing

Posted
5 minutes ago, MikeOH said:

@Shadrach

Is your RG35 rated at less than 33Ahr; I'm struggling to understand how twice the capacity yields you only an additional 15-20 mins?  I'd think if EarthX's 15.6 Ahr gives 1 hour then 33 Ahr would give you at least 2 hours.

As lead batteries age, their capacity decreases--that's why we do a capacity test every year. So what is the capacity of your battery right now? Nobody knows, especially not you when you are in the clouds.

Posted

We had an alternator failure on the way to Oshkosh this year. Somehow, the damn shot that did the last annual didn’t inspect the output wire of the alternator, all all that well and the wire arch and burned off of the end of the terminal which killed the alternator.  We flew about 18 more minutes and landed.  But anyway, here’s the deal. Its electrical load  is about 17 A in cruise and you can load shed it down to about 13. Now in that configuration  you could fly it probably almost 3 hours. And not so with the Earthx. So when we got to Chicago executive,  I took a Uber to the harbor freight and got a ring terminal and a hydraulic crimper and I stripped the wire and I fixed the airplane, or at least I think I did. I wasn’t really sure. But Oshkosh is an hour and 15 minutes away and my battery was  probably about 80% charged. So I got the cowl back on, one man style, and I went inside and washed up and then the line guy is like I’ll walk you out. He said well if you start up and it’s charging what are you gonna do and I said I’m going to Oshkosh. He said if you start up and it’s not charging what are you gonna do, I said I’m going to Oshkosh. I cranked it up, it’s charging, I went. But VFR you can go a long  way to someplace more conducive to get some repairs than Chicago PWK executive signature at 5 PM on a Sunday. 
 

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Posted
1 minute ago, Hank said:

As lead batteries age, their capacity decreases--that's why we do a capacity test every year. So what is the capacity of your battery right now? Nobody knows, especially not you when you are in the clouds.

I know what mine is, it’s about 95% of 33 amp hours. We test them all every year. 

Posted
5 minutes ago, jetdriven said:

I know what mine is, it’s about 95% of 33 amp hours. We test them all every year. 

I believe that's what it was when you tested it, but you don't know what it is right now.

Aren't we required to test battery capacity during annual?

Posted

The annual was about six weeks ago and we have flown it about 25 hours since then, so I bet it’s still 95%. And yes, we’re required to test them at annual according to Concorde, but all the pre-buys and all the logs and all the previous owners and all the planes I’ve worked on I’ve almost never seen a capacity test written down in the book. And all the talk of the airport restaurant is the guy was flying along and the alternator off light popped on, and then four minutes later everything in the plane went dark and they cranked the gear down. But it does not have to be that way.

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