EarthX Battery Box

[howelldw]

Hello,

Has anyone got a field approval on a EarthX battery box yet? If so, do you have a 337 example of what all had to be included to get it approved? The battery will get a STC approval in the near future, but the battery box isn't included in the STC. So, it will need a field approval. I think it can be done, but we are trying to figure out what all the FAA will want as far as drawings, specifications, and etc. Again, the box (particularly their thermal protected box), isn't STC'd or PMA'd. Any tips?

[GAHorn]

Are you trying to market it or use it in commercial (Pt 135) service..? or are you wanting this in your Pt 91 aircraft…?

If the latter, why not visit with your A&P/IA and discuss it as a possible minor alteration.

[howelldw]

It's a part 91 aircraft.

For the alternation to be approved at the FSDO level, we are seeking guidance of how to write it up.

I'm in A&P School and me and the IA are seeking some guidance on it since it is a non approved part.

I figured some of the tech types on here may have some input of to accomplish this.

I think this is one of these things we'd have to submit, get approved, then do the work.

[cessnut]

I wish I had a nickel for every time I've heard that an STC approval is coming soon.
My 2 cents: don't waste time on this until the STC is actually approved with your aircraft on the AML. At that point work with your IA to determine whether a battery box actually constitutes a major alteration, as George suggested to you.

[howelldw]

This post is only concerning a non approved battery box, not the battery. If there are any A&P/IA Types on here, I'd appreciate the feedback as to how to submit it for approval.

[Bruce Fenstermacher]

Dustin, I'm an A&P IA, but I haven't done a battery box mod, so I can't tell you how I've successfully done one.

You haven't given enough information about what you hope to accomplish with this battery box mod for us to determine if what you want in the battery box changes, is a major alteration. You've only indicated that you hope it holds a EarthX battery. If the box mods don't meet the requirement of a major alteration, then it is a minor alteration. Major alterations require approved data or a one time approval from the FAA and all work is documented on a form 337. If it is a minor alteration consistent with acceptable standards and practices, it is recorded in a log entry and no more approvals are necessary. (note: rewrote paragraph for clarity)

Off the top of my head, I'd say a battery box mod, by itself, is likely a minor alteration.

Who decides if it is a major or minor alteration? Your A&P with a review of Appendix A to Part 43. Of course the FAA might take exception to your A&Ps decision and that is one reason your A&P would be consulting with the Fed. Your A&P doesn't need close FAA over site going forward. Of course the next person who might take exception to your A&Ps decision is any A&P IA down the road who is tasked to complete an annual inspection who doesn't agree and won't sign off on the aircraft.

[cessnut]

Bruce summed it up pretty well, but since you insinuated that I am not an A&P/IA, allow me to clarify my statement above.
The EarthX thermal battery box is designed for an EarthX battery. The assumption is that you intend to obtain approval for the installation of the battery box in order to install an EarthX battery, since the box in question will not work with a lead acid for a couple reasons. That being said, my interpretation of Appendix A is that this battery would be a major alteration as it is a change to the basic design of the electrical system, hence you wait for the STC. If a STC is imminent for the battery, it most likely will contain some form of acceptable data that could be helpful in obtaining a field approval for the box.
To answer your question, there is not a cut and dried formula for obtaining a field approval. There are a couple ACs that discuss the requirements but it ultimately depends on the situation, what data you have available, and your relationship with the ASI. I usually discuss the proposal with my PMI before I start to put together a paperwork package. This can save you some unnecessary antics if it is something they are familiar with.

[GAHorn]

When I looked at the EarthX website..they indicate they make boxes for most common aircraft batteries.

If all that is desired is to provide a box for an already-approved aircraft battery…. this strikes me as a simple “minor alteration”…a logbook entry….and FSDO doesn’t need to be involved at all. I hope that clarifies my earlier post.

If, in the future, another A&P/IA sees that prior-approval (the minor alteration)…I doubt it would be re-visited or questioned. However, there are never any “guarantees” as to what some future inspector might question. (But he might need to have a wheelbarrow to carry his cojones in.) They might also question an STC’d product due to a myriad of issues as well.

<edit> Referring back to the original question: It appears that lownslow is asking us to reveal what FAA will require to STC a Battery box on a battery which Itself is not-yet STC’d. It’s not likely any of us will be able to speak for whatever FAA office is queried… that question will have to be directed to FAA, which should be able to provide the data they will require, and the EarthX folks should be capable of demonstrating their box (and expected STC’d-battery) will meet those requirements. Hope that helps.

[n2582d]

I’m with Cessnut on this; one needs to talk with your PMI for guidance here. On the one hand, this is a CAR 3 certified aircraft so one might think that as long as the battery box meets the requirements of CAR 3.682, 3.683 and 3.684 you’re legal. A rather low bar as protection against acid and proper venting were the main concerns with lead acid batteries. But on page 9 in Appendix A of the AML for the 12 volt EarthX battery, STC Certification Basis indicates that Part 23 fire proof requirements need to be meet. (Actually, in this appendix, it says that the battery box should withstand 20,000 F — twice the temperature of the sun’s surface — for 15 minutes but that’s a typo — the last zero should be a degree mark — 2000°F).

IMG_1346.jpeg

Stainless steel melts at a temperature above 2500°F while our aluminum battery boxes will turn to a molten puddle at around 1220° F.

Study FAA Order 8110.48A and AC 21.101-1B for further information on why you can’t just refer to CAR 3 requirements here. Also see AC 20-184 “Guidance on Testing and Installation of Rechargeable Lithium Battery and Battery Systems on Aircraft”.

What I don’t understand is how EarthX was able to get their battery approved in the C-172 using the existing aluminum battery box and a foam insert as seen here. I’ve asked them to chime in. Hopefully they’ll clear this up.

[GAHorn]

I’ll suggest that exposing ANY PART of the aircraft to 2,000 degrees for Ten Minutes will likely “result in hazard” to the airplane. The Peak Exhaust Gas Temps don’t reach that high. Doh.

Pls note I edited my prior comment, … as I reconsidered what I would probably do if it were my airplane and felt my previous comment did not reflect reality.

[n2582d]

Are you trying to market it or use it in commercial (Pt 135) service..? or are you wanting this in your Pt 91 aircraft…?

If the latter, why not visit with your A&P/IA and discuss it as a possible minor alteration.

George, I’m not familiar with the answer to a major/minor alteration question being different for part 91 and part 135 aircraft. Could you enlighten me? Perhaps you’re thinking of TSO requirements?

[GAHorn]

Are you trying to market it or use it in commercial (Pt 135) service..? or are you wanting this in your Pt 91 aircraft…?

If the latter, why not visit with your A&P/IA and discuss it as a possible minor alteration.

George, I’m not familiar with the answer to a major/minor alteration question being different for part 91 and part 135 aircraft. Could you enlighten me? Perhaps you’re thinking of TSO requirements?

I was referring, in general, to the increased mx/documentation/overhaul req’s of commercial service, Pt 135 being one. I’m not certain that the solution I was suggesting could qualify in/on a Pt 135 operation, was my only point.

[ghostflyer]

I have been using an Earth X battery now for 2 years and totally amazed at its performance and it sits in a standard cessna battery box mounted on the firewall with foam to keep it secure . The original bottom vent in the battery box now has air blown through it from the slip stream. I went to our local authorities [australia] for guidance [ ] and because I have a stainless fire wall they didn’t have any issues with the installation.