Mooney AML STC for LiFePO4 Batteries - Need info - Firewall forward?

[BrentO2]

Folks:

Does anyone know how I can figure out what Models of M20, and what Serial numbers may have Batteries Firewall forward?  I thought they were all aft area, but looks like that is NOT true. Help!

BrentO2 - FAA DER, Electrical

[carusoam]

Welcome aboard Brent!

There is a Mooney timeline around here, and elsewhere… that lists every change of every model…

The older Mooneys mounted the battery on the firewall…. My 1965 M20C was done that way…

Under the cowling is a crummy environment for the battery… soooo… they moved towards the tail… 

Find the timeline for more details…

 

For comparison…

When your M20K was built… the extra cylinders and turbo system added additional weight on the nose…

A pair of batteries in the tail was used to nicely bring balance back to the force of gravity…. 
 

Private Pilot thoughts only, not an aircraft historian….

best regards,

-a-

[carusoam]

Also Brent…

If you can…

Introduce yourself… add a little more detail…

There is plenty of Mooney knowledge, combined with battery knowledge and other types of knowledge…

That can make your journey more complete…

Best regards,

-a-

[FoxMike]

Models B and C have Battery in the front.  E models and later have rear mounted.

[Andy95W]

35 minutes ago, FoxMike said:

Models B and C have Battery in the front.  E models and later have rear mounted.

We need to check with an M20G owner (maybe, @Utah20Gflyer) to confirm about the G model.

IIRC, the battery move was based on the heavier IO-360 engine, which means all the carbureted models (probably including the M20A) had the battery in the front.

[Utah20Gflyer]

23 minutes ago, Andy95W said:

We need to check with an M20G owner (maybe, @Utah20Gflyer) to confirm about the G model.

IIRC, the battery move was based on the heavier IO-360 engine, which means all the carbureted models (probably including the M20A) had the battery in the front.

G model Mooney's have the battery in the front.  

[A64Pilot]

Before you put too much work into a lightweight battery, investigate its effect on W&B, if you have to add ballast to offset the lighter battery then maybe it wasn’t very effective. I believe however as certain Mooney’s have “charlie” weights ballasting a Mooney would be a simple thing to get approved.

‘Then if you live where it gets real cold, a Lifepo4 may not be the best choice either.

[Hank]

It would be nice to have a lighter battery up on my firewall, to help offset the extra weight from the 3-blade Hartzell . . . .

[BrentO2]

Thanks Gents!  Per a request, more info is on my Website: OlsenTechLLC.com, but I am an Air Force and Navy (Naval Air) Veteran with Masters in Electrical Engineering/Mgt.  I am an FAA DER - Electrical Systems & Equipment in the Denver area.  I have worked these Li Batteries now for over 15 years starting with Aircell/GOGO, and this EarthX is the best and a great life and price point.  The fact it was the first battery to meet TSO-C179b (not older "a") is important as this one passed (well) all the RTCA DO-311A and DO-347 applicable regulations (Consensus standards) to Part 23 series reg's, even 23.2525, etc. Requirements have evolved for sure, but the Nine Special Conditions for Lithium batteries to AC 20-184 were easily met.  This battery is top notch in my review, and based on many years of product development and FAA experience. Life of 6 Years or more is expected if you just take care of them. Special LiFePO4 chargers are important.

One important note for at least one of you is the fact they DO really crank!  Way better than the other lead-acid or gel-cells.  Not to mention the weight, of course. And, after the very first crank they internally heat and work fine down to -20C - for first crank where we tested in Colorado in the winter (with battery cold soak at -20C 3 hours). My experience (and PoH's) do not recommend the crank at those very low temps for a lot of other more important reasons and why we have heaters in Alaska, for instance. After that first crank on the C182P, it cranked very well due to that internal heating.  If less than -20C, then consider a local heat application.  Does not take a lot as the battery is only 5.4Lbs mass. Again, what I see is after that first crank it goes like mad!

On firewall forward, I thank you all for the direction.  I see now that Models A-D are FWF and starting at Model E, SN 470 they transition to AFT installation.  We will exclude (for now) the FWF, but stay tuned.  We soon will have the 28V battery FWF.  Thank again all, appreciate you as I am new to Mooney. Cheers!

BrentO

[David Lloyd]

A some of C models with a 3 blade prop have the battery relocated aft for balance. Same for D and G models. 

[LANCECASPER]

2 hours ago, BrentO2 said:

We soon will have the 28V battery FWF.  Thank again all, appreciate you as I am new to Mooney. Cheers!

BrentO

There are no FWF 28 volt Mooneys. All 28 volt Mooneys have the batteries in the tail.

[Hank]

3 hours ago, David Lloyd said:

A some of C models with a 3 blade prop have the battery relocated aft for balance. Same for D and G models. 

Some. Certainly not mine! That's why a much lighter battery is so interesting!

[carusoam]

Brent,

Thank you for filling in so many details!

Hang out for a bit, check in often… I’m sure more questions and answers will be coming…

The most modern Mooneys are the Long Bodies…

The most weight challenged Mooneys are SOME Mid Bodies that are loaded with options…

Each LB has a pair of batteries in the tail… along with a few other things fighting for space, and weight…

Where these light weight batteries make a lot of sense… is when the Mooney owner is unable to have all the things they want in the back…

Mooneys have the following options back there…

1) Pair of batteries… often, 24V Concorde gel cells that are known to last over 6years, often using a battery specific BatteryMinder (charger).

2) A stack of Charlie weights… (the opposite of usable weight). The CWs get replaced when other useful pieces of hardware get installed…

3) Air conditioning…

4) FIKI anti-icing systems…

5) Built in Oxygen system…

6) Remote Avionics…

 

So… a light weight battery is not for every Mooney TODAY…

But, when it is time to swap in new hardware like a different prop, or AC… the Battery is often selected to either add weight or subtract weight…

XC or extra capacity batteries may be used to balance the extra weight of a heavier prop put on the nose…

Comparisons of the new type batteries to the latest Concorde gel cel are interesting…

I would have to get at least three heavy options to be able to throw out the Charlie Weights and want to go to a lighter battery…

We were recently discussing battery heaters just a few days ago… an MSer had one, because his plane came from a colder climate… pics recently posted…

PP thoughts only, not a mechanic…

Best regards,

-a-

[A64Pilot]

Being a little nose heavy on many aircraft isn’t often a bad thing as it’s real difficult to load to where you get out of fwd CG. Because the CG is close to the spar and most places where you can fit stuff is behind that its often not too hard to load out or close to aft CG, plus fwd CG is more stable and if you do a lot of hand flying IFR it’s easier to hold altitude, it’s slightly slower but not by much at all. Everything is a trade off.

The 12 lbs the three blade added to the nose of my Maule made it capable of carrying more stuff as aft CG was the real limit of what it could carry.

On my J model there is no conceivable load that can get me close to fwd CG, not even two 300lb people in front and everything else empty so I could probably take a lighter battery, but I suspect that’s not true for many Mooney’s 

Edited April 21, 2022 by A64Pilot

[BrentO2]

Thanks again folks!  The MEC (Model Evaluation Checklist) in the IMM is key as there are limitations (Such as Over Voltage Protection and Alternator 80A or less).  As a pilot and aircraft owner/builder myself, CG is watched closely, but as you all point out, many factors are at play.  Interesting to hear about the forward CG.

Every Model serial number is different based on STC's installed or Mod's done on any given airplane.  It is a must to run the checklist to ensure your model is eligible.  Unfortunately, the FAA is rather slow right now, so we are sorry this is taking so long.  Stay tuned, the 28V may be a good deal for many of you as it will also be FWF qualified.  Cheers!

Brent G. Olsen, P.E. (FAA DER)

[Hank]

11 minutes ago, BrentO2 said:

Every Model serial number is different based on STC's installed or Mod's done on any given airplane.  It is a must to run the checklist to ensure your model is eligible.  Unfortunately, the FAA is rather slow right now, so we are sorry this is taking so long.  Stay tuned, the 28V may be a good deal for many of you as it will also be FWF qualified.  Cheers!

Brent G. Olsen, P.E. (FAA DER)

Brent--

The only Mooneys with FWF batteries are 12 V. The 28V ships all carry their battery in the avionics bay, and some carry two batteries in the tail.

My M20-C has it's 12V battery on the engine side of the firewall, and a battery weight reduction would be beneficial for me, to offset some of the extra weight from my 3-blade propeller.

[BrentO2]

Hank, we will be getting there on 14V, Firewall Forward, just not this round of AML STC. Thanks a lot for the info on the 12V (14V Elec System) it is good to know all are 12 Volt Batteries.  Looks like 28 V came later in the M20 Series.  I can see that one easily, the issue I have is I thought the FW Aft started at M20E (470E), but one member says G too.  So ":More Research" is needed...  I appreciate your response.

 

[BrentO2]

M20 Folks:

Does anyone have an idea where I can get ALL the Parts Catalogs for the M20 Series?  I have one, but it does not cover the entire series.  I only need up to M20K to Serial 0999, as it looks like 24V Battery starts at 25-1000.

BrentO

[Hank]

Yes, 12V FWF are on M20-A, B, C, D and G (all have O-360 engines). Apparently the battery was moved to the avionics bay when the IO-360 was introduced on the M20-E, F and J.

Not sure when the 12V->23V conversion was made. I think some Js are 28 V.

Some later Mooneys have two.batteries in the ta--M20-R comes to mind.

[Fly Boomer]

Others are more knowledgeable, but I suspect the answer is your favorite MSC (Mooney Service Center).  Mooney web site shows where they are.

[BrentO2]

Got it!  Thanks.  I do have a couple of messages into support at Mooney.  Looks like we exclude M20G then, will adjust the list. Thanks again.

[A64Pilot]

What is it your trying to do? STC? which battery will you use?

[BrentO2]

A64Pilot:

EarthX ETX900-TSO Battery AML STC SA01005DE. 5.4 Lbs, meets all the latest FAA Requirements (TSO-C179b) including all 9 Special Conditions of AC 20-184 for installations.  We are adding to the AML.

BrentO

 

[A64Pilot]

AML / STC?

Do you have an estimate as to cost for STC?

[BrentO2]

A64Pilot:

There is NO cost for the STC per se, as you buy a TSO Battery and STC Install Kit.  All Data will be on the Website your A&P can access.  The install kit includes the LED Caution Light, a Placard, and misc. parts such as Teflon vent tubing and connections. Here is the DRAFT install kit.  See the Website for more EarthX info, such as the IMM, I am the Consultant DER for them, not a FT employee.

BrentO

Palm Harbor, FL

Loveland, CO

ETX900-TSO-35-M20-KIT 35Ah Battery Install Parts Kit.pdf