Changing battery type

Tom-D

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Tom-D
IAW 21.93
is the change from a wet cell Gill 25 to a 12V dry cell a major or minor alteration.

3 pounds lighter at the datum line of the aircraft, changes the EMPTY weight of a 1250 pound aircraft by 3 pounds.

I do not see it as a major.
What say you ?
 
My opinion is minor, just update the W&B. But I'm not an A&P.
Why would you think it may be otherwise?
 
Does it require the fabrication of a new battery box?
 
"""""
installation of Concorde Aircraft Batteries.

FAA AC No. 23-27 allows the replacement of Gill batteries with FAA-PMA Concorde batteries, on fixed wing, unpressurized, up to 12,500 lbs, with reciprocating engines, or sailplanes TC'd before January 1980, even though those TC's may have been revised after that date (current manufactured aircraft) with only a logbook entry.

FAR 43.3(g) and 43.7(f) allows holders of a private pilot certificate to preform preventative maintenance and APENDIX A (c) Preventitive Maintenance (24) Replacing and servicing batteries.

There now is no need for STC's or Field Approval to install Concorde batteries if their weight is + or- one pound of the battery that was certified as original equipment

Skip Koss
Concorde Battery Corporation 626-813-1234 x 231"""""""
 
I was just going to edit my post to ask if there was any work needed beyond a battery swap.
No new box required, no structure changed, simple slip in.
only difference is it's a rechargeable dry cell, and it is smaller/lighter.
 
What would you use as justification that it’s a major modification?
 
So...what’s the rule bout installations of more or less than (1) pound? :confused:
 
AC43.13-2B chapter 10 covers it. Minor or major? Its up to the mechanic. If an IA wants to do a 337? The instructions are in the opening paragraph of the AC. Want to pitch the old flooded battery and put an Odyssey on the firewall or under the floorboards? You can do that. No field approval required. Been that way for many years.
 
What would you use as justification that it’s a major modification?
As I've said in my first post, I do not see it as a major.

But I do see aircraft that have 337s field approvals for this modification.
 
As I've said in my first post, I do not see it as a major.

But I do see aircraft that have 337s field approvals for this modification.
I ask the question again. What was used to justify it as a major mod?
 
Note that the RG batteries are NOT "dry cells." A dry cell would be something like a NiCad which would not only be illegal to put in as a "minor alteration" but incredibly dangerous.
 
Note that the RG batteries are NOT "dry cells." A dry cell would be something like a NiCad which would not only be illegal to put in as a "minor alteration" but incredibly dangerous.
NiCad is not a dry cell.
 
Note that the RG batteries are NOT "dry cells." A dry cell would be something like a NiCad which would not only be illegal to put in as a "minor alteration" but incredibly dangerous.

NiCad batteries are specifically allowed in 43.13-2B chapter 10. The reference to "dry cell" is usually a slang reference to AGM batteries, which are still lead-acid type and also allowed in 43.13-2B.

EarthX now has TSO approval for their ETX-900vnt battery (lithium ion) and I hear guys are getting field approvals for those. The say STCs are coming soon.
 
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NiCad batteries are specifically allowed in 43.13-2B chapter 10. The reference to "dry cell" is usually a slang reference to AGM batteries, which are still lead-acid type and also allowed in 43.13-2B.
Must be some local slang, because I've never heard of the term MISUSED in that fashion before. Not only are they still lead-acid, they're flooded wet cells, not even gelled electrolyte.
I wasn't challenging that RG batteries couldn't be used.
 
IAW 21.93
21.93 not applicable in this scenario. A major/minor change to type certificate is not the same thing as a major/minor alteration. Major/minor changes to TC are outside the ability of a A&P/IA and are determined at the FSDO/MIDO/FSDO levels. Plenty of guidance docs on this:

"The use of the terms “major” and “minor” are sometimes inappropriately applied or misunderstood. A major change in type design can be approved only by an ACO as an amended type certificate (ATC) or Supplemental Type Certificate (STC). A major alteration requires the use of FAA-approved technical data. Minor alterations only require data that is acceptable to the FAA. During an evaluation, an anticipated major alteration may be subsequently classified as a major change in type design, and thus would require application for an amended TC or STC."
https://www.faa.gov/documentLibrary/media/Order/8300_16_CHG_1.pdf

In your battery example, if the replacement battery is of the same type (25, 35) and weighs the same within a pound you can swap it out as a minor alteration per the above mentioned AC23-27. Unfortunately, the weights are different so the AC would not apply so that would take you back 43 Appx A(a)(vii). However, if your replacement battery is PMA'd as a replacement (plug n play) for your aircraft model then it could also be installed under a logbook entry and an A&P correction of the wt/bal report. Anything short of that would fall under a major alteration.

Where 21.93 (major change) could come into play is if this 12v dry cell has no approval and you apply for a field approval to install. If the FSDO determines it is not a minor change to TC then they would forward your request to the ACO. If the ACO determines it's a major change to TC then you would have to pursue a STC to install it and not a field approval.
 
Note that the RG batteries are NOT "dry cells." A dry cell would be something like a NiCad which would not only be illegal to put in as a "minor alteration" but incredibly dangerous.
I agree a NiCAD cell probably isn't a minor alteration, but NiCad batteries have been, and still are, used on commercial and business aircraft. I'm not sure why you consider it dangerous.
NiCad is not a dry cell.
@Tom-D has it correct here, for aviation uses. There have been dry cell type NiCad batteries for many years, before being supplanted by NiMH and LIon batteries, but these aren't used for main batteries on aircraft.
 
EarthX now has TSO approval for their ETX-900vnt battery (lithium ion) and I hear guys are getting field approvals for those. The say STCs are coming soon.
MidContinent's 'True Blue Power' is doing STC for their Lithium-ion as well, they have one for the Bonanza for only $7,700.
 
21.93 not applicable in this scenario. A major/minor change to type certificate is not the same thing as a major/minor alteration. Major/minor changes to TC are outside the ability of a A&P/IA and are determined at the FSDO/MIDO/FSDO levels. Plenty of guidance docs on this:

"The use of the terms “major” and “minor” are sometimes inappropriately applied or misunderstood. A major change in type design can be approved only by an ACO as an amended type certificate (ATC) or Supplemental Type Certificate (STC). A major alteration requires the use of FAA-approved technical data. Minor alterations only require data that is acceptable to the FAA. During an evaluation, an anticipated major alteration may be subsequently classified as a major change in type design, and thus would require application for an amended TC or STC."
https://www.faa.gov/documentLibrary/media/Order/8300_16_CHG_1.pdf

In your battery example, if the replacement battery is of the same type (25, 35) and weighs the same within a pound you can swap it out as a minor alteration per the above mentioned AC23-27. Unfortunately, the weights are different so the AC would not apply so that would take you back 43 Appx A(a)(vii). However, if your replacement battery is PMA'd as a replacement (plug n play) for your aircraft model then it could also be installed under a logbook entry and an A&P correction of the wt/bal report. Anything short of that would fall under a major alteration.

Where 21.93 (major change) could come into play is if this 12v dry cell has no approval and you apply for a field approval to install. If the FSDO determines it is not a minor change to TC then they would forward your request to the ACO. If the ACO determines it's a major change to TC then you would have to pursue a STC to install it and not a field approval.

Lots of info. but I don't believe it applies.
read
https://www.batterymart.com/p-hawke...MIwfbf6rXz4gIVELvsCh2RbQW2EAAYAiAAEgKZLfD_BwE

when you notice that there are STC and several apporvals all ready on record.
AS per my PMI, at most would require a deviation to any STC that applies to this particular battery, to install in any aircraft not on the application list.
 
to install in any aircraft not on the application list.
Must have missed battery link earlier. Since it's already approved (STC/PMA) contact the STC holder and inquire on adding the aircraft you need to the list instead of using a "deviation." The holder can add an aircraft to the approved AML with a stroke of the pen and then you'll have the STC and/or possibly a PMA to use.
 
I agree a NiCAD cell probably isn't a minor alteration, but NiCad batteries have been, and still are, used on commercial and business aircraft. I'm not sure why you consider it dangerous.
Because those aircraft are designed for them. NiCads have a very different mode of charging and also have a very low internal resistance. Both of these will likely result in a FIRE if you just subsitute a NiCad in a circuit expecting a Lead-Acid battery. The new LiOn car batteries incorporate their own builtin charging/regulation circuit to make them appear to behave like a lead acid battery
 
NiCad batteries are specifically allowed in 43.13-2B chapter 10. .
BullPoop. It doesn't say you can put a NiCad battery in as a replacement for a Lead Acid. It talks about servicing/replacing NiCad batteries in aircraft (commonly small jets) that were certified for them.
 
Because those aircraft are designed for them. NiCads have a very different mode of charging and also have a very low internal resistance. Both of these will likely result in a FIRE if you just subsitute a NiCad in a circuit expecting a Lead-Acid battery. The new LiOn car batteries incorporate their own builtin charging/regulation circuit to make them appear to behave like a lead acid battery
Actually, the charging circuits are designed for them, hence my comment about it no longer being a minor alteration. There are also ventilation considerations. There are replacement lead-acid batteries for those aircraft. In any case, the NiCAD is being phased out due to the cadmium.
 
Actually, the charging circuits are designed for them, hence my comment about it no longer being a minor alteration. There are also ventilation considerations. There are replacement lead-acid batteries for those aircraft. In any case, the NiCAD is being phased out due to the cadmium.
I suspect you're agreeing wth me. You can't just hook up a NiCad on a system expecting a lead acid.
 
Can we stop the NiCad BS it has no place here. this is a simple "DRY CELL"
 
3 pounds lighter at the datum line of the aircraft, changes the EMPTY weight of a 1250 pound aircraft by 3 pounds.

Only 3#? I saved 10# by switching from a Concorde to an Odyssey.

But my plane's experimental, so all I had to do was note it in the log and update the W&B. It's not a "major change" because it "has no appreciable effect on the weight, balance, structural strength, reliability, operational characteristics, or other characteristics affecting the airworthiness of the product."
 
Can we stop the NiCad BS it has no place here. this is a simple "DRY CELL"
But it isn't. An RG is not a dry cell (nor does it contain dry cells).

And three pounds lighter ANYWHERE (doesn't matter where it is with respect to the datum) is three pounds lighter empty weight.
 
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