Saving some battery weight.

[65eTurbo]

The old Gill died.  Replacement is the same amperage but 12 lbs lighter.  A mounting bracket can be bought with the battery.

Anyone else do this?  

 

[Guest]

41 minutes ago, 65eTurbo said:

The old Gill died.  Replacement is the same amperage but 12 lbs lighter.  A mounting bracket can be bought with the battery.

Anyone else do this?  

 

F Atley Dodge has an STC for this in some Cessna singles.  You might check with them.

Clarence

[A64Pilot]

Run your W&B, you may not want to do it. Either way an IA will be involved, so if you don’t have one in it, might want to talk to them first.

In my J I don’t think I would, moving the CG forward unless it’s needed can be counterproductive

[Raptor05121]

I didn't think they were legal for us. Has that changed?

[A64Pilot]

Anything can be done with a field approval, but getting one is likely to cost way more than it’s worth, so get whoever will seek the approval onboard first, before you spend any money.

Realize when I say anything that’s tongue in cheek, getting multiple DER’s involved in one often makes it cost more than it’s worth. Put one time STC in there with field approval as I think that’s where this might end up.

[smwash02]

Whether you can or not, I wouldn't want to give up half the capacity for a 15lbs and risk being stranded.

The J16 is 15Ah and 15lbs. The RG-35A is 29Ah/29.5 and AXC 33/32.

[carusoam]

Summary…

1) Approval challenge…

2) Weight and balance challenge… mock up the calculations to see how much it moves the Cg… you don’t want to fall out the back… or the front.

3) Capacity challenge…

 

With a single battery like my old M20C…. A cold start was tough on the full capacity battery…. Cutting its capacity in half would not work out very well…

That would work out, if the engine always started on the fourth blade to go by…

Some battery swaps like this end up replacing some of the missing weight with Charlie weights…

Consider it as an opportunity… it might make a nice part of a two battery system… for Mooneys with only one battery…

Two battery systems take some stress out of starting challenges…

 

PP thoughts only, not a mechanic…

Best regards,

-a-

[A64Pilot]

The AH rating isn’t about starting, it’s how much power can be drawn from a battery over time before voltage drops below usually 10 or 10.5 V
Cranking amps is really quite different, it’s how many amps can a battery supply for a very short time frame, due to its very short duration cranking takes very little AH.

Some of these thin plate automotive batteries can have big CCA, but relatively low AH rating.
 

Cold cranking amps is how many amps can a battery supply at 0F for 30 sec. with it dropping to 7.2 V, are aircraft batteries rated in CCA?

Why AH is important is that’s how much power / time you have for your Nav / Comm gear to work if the Alt quits.

If a battery is behind the baggage compt and you lose 12 lbs, sure you gain 12lbs useful, but the forward CG shift will slightly slow you down too, enough maybe to have to carry 12 lbs more gas for your trip maybe?

Edited March 17, 2022 by A64Pilot

[65eTurbo]

My IA suggested it and has the field approval lined up.  We will mount it to the aft of the battery box.  With more work, I could mount to the back of the avionics tray with the CG a foot further aft, if I wanted to maintain CG.

It is STC for Cessna 195 and has rave reviews online and word of mouth.

My E is a little unique in that it has the back seat relocated rearward.  If I want to carry back seat passengers I wind up at the aft CG limit and bags have to be positioned in the back seat.  For example, flying 2 kids to camp or Airventue with camping gear.  This will let me put a bag behind the seat.

For solo flying, I'm going to add an emergency bag tie down in the back corner of the hat rack.  Right now it is back floor of the cabin.  Will push the CG as far back as I can.

I'll report back with results.

[A64Pilot]

Sounds like you have the bases covered, approach aft CG with a little caution, the further aft you go the less stable you are in pitch and control pressures are lighter

[65eTurbo]

2 minutes ago, A64Pilot said:

Sounds like you have the bases covered, approach aft CG with a little caution, the further aft you go the less stable you are in pitch and control pressures are lighter

Yep, she flies best at aft CG.  just don't spin her.

Edited March 18, 2022 by 65eTurbo

[carusoam]

8 hours ago, A64Pilot said:

The AH rating isn’t about starting, it’s how much power can be drawn from a battery over time before voltage drops below usually 10 or 10.5 V
Cranking amps is really quite different, it’s how many amps can a battery supply for a very short time frame, due to its very short duration cranking takes very little AH.

Some of these thin plate automotive batteries can have big CCA, but relatively low AH rating.
 

Cold cranking amps is how many amps can a battery supply at 0F for 30 sec. with it dropping to 7.2 V, are aircraft batteries rated in CCA?

Why AH is important is that’s how much power / time you have for your Nav / Comm gear to work if the Alt quits.

If a battery is behind the baggage compt and you lose 12 lbs, sure you gain 12lbs useful, but the forward CG shift will slightly slow you down too, enough maybe to have to carry 12 lbs more gas for your trip maybe?

My example is how I ran out of energy trying to get the plane started… 20°F outside in NJ… no pre-heat…

Never ran out of power during ordinary operations… (except that one time in VMC… fried / dead generator)

My O360 got two extended attempts at trying to start… after which, it was pretty well dead… and not coming back.

Do our batteries get a rating for CCAs?

Does this battery magically work better with starting loads?  If yes, how so?

Searching to see how this can work better in the Mooney world…

MSers have so many different use cases…

This light weight option may be good for some…?

Is there more to it… than half the capacity at half the size, (same current, same voltage)?

Best regards,

-a-

[carusoam]

What does the C195 world like about it?

They May like it for some non-Mooney related reason…

Nice that it gets good pireps… but what were they saying about it….?

 

If their prior battery leaked acid all over the place, and this one didn’t… nice, but Mooney batteries don’t leak anymore…

If their prior battery was so large, they couldn’t fit their X-country skis in the back…. Nice, but my skis won’t fit until I get those fancy short shaped skis…

Kind of a technical request for more information…

Best regards,

-a-

[GeeBee]

I had the J16 in my SuperCub with an O-320, 160hp. It worked really good and my IA was always amazed at it. I also had a full glass panel, Aspen, Garmin 430, Lynx Transponder etc. It kept right up with it. 

I have an old one, about 7 years old powering an electric fence charger to keep the squirrels off the bird feeder. The squirrels are still really ticked off, so it must be working.

[carusoam]

Hawker j16 battery website…. 

https://www.enersys.com/en/products/batteries/hawker/?page=1&capacity=0&industries=9&applications=&technologies=&designs=&communicationcapabilities=&voltages=

Couldn’t get to the J16 battery that way….

Same company makes submarine batteries…. 
 

most info available I could find… lots of tech details… including STC purchasing info…

https://www.aircraftspruce.com/catalog/elpages/odysseydry7.php

 

Which leads to a spec sheet…. For the J16 battery used in the telecom industry….

https://www.aircraftspruce.com/catalog/pdf/EngSysBrochure.pdf

 

Gets more interesting by the day… but not if you are a squirrel….

PP thoughts only,

-a-

 

 

[mooniac15u]

15 hours ago, 65eTurbo said:

My E is a little unique in that it has the back seat relocated rearward.  If I want to carry back seat passengers I wind up at the aft CG limit and bags have to be positioned in the back seat.  For example, flying 2 kids to camp or Airventue with camping gear.  This will let me put a bag behind the seat.
 

How do you relocate the rear seats rearward?  The structure below them can't be moved.  Does the front of the seat no longer align with the structure?  Do you have a picture of this?

Edited March 18, 2022 by mooniac15u

[A64Pilot]

Car starting batteries or generally just say starting batteries can get higher cranking amps by having the same amount of lead spread out through more plates, more plates are more surface area and surface area will give you more cranking amps. So it is possible to get a lot of CCA out of a smaller and lighter battery

However as a general rule thin plate batteries are less rugged and poor deep cycle batteries, just remember TANSTAFL. Aircraft batteries, especially Concorde batteries are actually very good deep cycle batteries, they need to be to continue to deliver power until we get on the ground. The Lifeline battery is Concorde’s deep cycle batteries and has essentially the same construction as the Concorde aircraft batteries, they are one of I believe only two AGM “true” deep cycle batteries, I think Rolls makes the other one, they are not aircraft batteries, but sold for sailboats etc.

The 660AH bank in my sailboat were Lifelines, it’s where I really learned about the care and feeding of batteries, they are VERY important to cruisers

https://lifelinebatteries.com.

The Holy grail for aircraft batteries is more power with less weight, for example a flooded aircraft’s batteries acid is stronger acid as evidenced by the specific gravity, it’s done to ge a little more power.

If you could get a large decrease in weight but keep the power, then Concorde would, and they would OWN the aircraft battery business. but they haven’t and it should make you think why not.

BTW Concorde is building LifePO4 batteries for the Military, Lithium is coming, but I don’t have a clue what it will cost or when it will happen.

 

Edited March 18, 2022 by A64Pilot

[65eTurbo]

On 3/18/2022 at 7:55 AM, mooniac15u said:

How do you relocate the rear seats rearward?  The structure below them can't be moved.  Does the front of the seat no longer align with the structure?  Do you have a picture of this?

It was ait was a 337 by the previous owner of LASAR.  Back seat back is narrowed and  moved rearward.  Seat bottom winds up longer.  Seat back is made removable and flip fold.  Also front sear backs are doglegged to move Seat bottoms forward relative to the back to create toe room.

I'll try to dig up pictures.

[65eTurbo]

6 minutes ago, 65eTurbo said:

It was ait was a 337 by the previous owner of LASAR.  Back seat back is narrowed and  moved rearward.  Seat bottom winds up longer.  Seat back is made removable and flip fold.  Also front sear backs are doglegged to move Seat bottoms forward relative to the back to create toe room.

I'll try to dig up pictures.

[47U]

Interesting concept…

[65eTurbo]

20 hours ago, 47U said:

Interesting concept…

I've had 4 guys 6 feet or more in comfortably.  Range then is the issue.  Nice to be able to remove the seat too.

[larrynimmo]

On 3/17/2022 at 10:03 PM, carusoam said:

What does the C195 world like about it?

They May like it for some non-Mooney related reason…

Nice that it gets good pireps… but what were they saying about it….?

 

If their prior battery leaked acid all over the place, and this one didn’t… nice, but Mooney batteries don’t leak anymore…

If their prior battery was so large, they couldn’t fit their X-country skis in the back…. Nice, but my skis won’t fit until I get those fancy short shaped skis…

Kind of a technical request for more information…

Best regards,

-a-

That’s why I got rid of my 195 alpine skis and downsized to 169…much better fit in the plane…much easier to skid turn, not so great for stopping though

[65eTurbo]

On 3/18/2022 at 3:07 PM, A64Pilot said:

Car starting batteries or generally just say starting batteries can get higher cranking amps by having the same amount of lead spread out through more plates, more plates are more surface area and surface area will give you more cranking amps. So it is possible to get a lot of CCA out of a smaller and lighter battery

However as a general rule thin plate batteries are less rugged and poor deep cycle batteries, just remember TANSTAFL. Aircraft batteries, especially Concorde batteries are actually very good deep cycle batteries, they need to be to continue to deliver power until we get on the ground. The Lifeline battery is Concorde’s deep cycle batteries and has essentially the same construction as the Concorde aircraft batteries, they are one of I believe only two AGM “true” deep cycle batteries, I think Rolls makes the other one, they are not aircraft batteries, but sold for sailboats etc.

The 660AH bank in my sailboat were Lifelines, it’s where I really learned about the care and feeding of batteries, they are VERY important to cruisers

https://lifelinebatteries.com.

The Holy grail for aircraft batteries is more power with less weight, for example a flooded aircraft’s batteries acid is stronger acid as evidenced by the specific gravity, it’s done to ge a little more power.

If you could get a large decrease in weight but keep the power, then Concorde would, and they would OWN the aircraft battery business. but they haven’t and it should make you think why not.

BTW Concorde is building LifePO4 batteries for the Military, Lithium is coming, but I don’t have a clue what it will cost or when it will happen.

 

I believe deep.cycle is a question of durability for multiple deep discharges which is not the design requirement for aircraft alternator failure, right?  One hopes.  

If it starts reliably and runs the panel for an hour, I'll give it a shot.

My IA has been installing variants of lightweight batteries in jets.  Eyewatering costs.

As for Lithium, the FAA won't field approve the available batteries because of crash worthiness issues and post impact fire. (We tried). I've seen them for race cars.  Astonishingly light.

[A64Pilot]

All that really matters is if your battery meets or exceeds the AH requirement, so that you have the reserve capacity, if it does then in my opinion it’s fine. it has to start the engine of course, but if it meets the AH requirement, then surely it will

It’s pretty much a given that deep cycle batteries have more AH capacity, but less cranking amps per pound of battery.

FAA is stuck in the past, LifePO4 is really, honestly safer than lead acid. It will happen, just takes time, Concorde is manufacturing LifePO4 batteries for the Military and that’s where a lot if not most of our standards originate.

https://www.concordebattery.com/about/us-navy-lithium-ion-contract-ch-53k.html

 Most don’t understand the huge difference in Lithium chemistries, Li-ion is dangerous and there are many different chemistries of it, Li-Po is the same really as Li-Ion, just it’s pouch cells and not in a can., much easier to fit in a phone or Ipad or whatever.

But LifePo4 is very different, it’s much safer, but as there is no free lunch, it’s only about half as energy dense as Li-Ion or Li-Po

https://www.batterystuff.com/kb/articles/battery-articles/lithium-battery-overview.html

Having said that if you live in a cold place, then Lithium of any chemistry is probably not a good choice, they don’t like real cold Wx.

Edited March 29, 2022 by A64Pilot