PA-18 Under Rear seat battery field approval

I currently have the stock battery mounted aft of cabin. I also have the rear under seat storage compartment. I’d like to switch to a lightweight battery and given I already have the rear seat storage compartment I’d like to utilize it for the battery mount. Has anyone done this and received a 337 for it? If so, any chance you would be willing to share a copy? If so, please email to andymeyer50@icloud.com. Thanks!

no field approval needed...(anymore)

look in the second half of 43.13... it covers battery installations ...

mike mcs repair said:

no field approval needed...(anymore)

look in the second half of 43.13... it covers battery installations ...

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Ahhh... thanks for the heads up. Any chance anyone has a pic of their installation?

I really like the Willow Mountain STC that puts the battery between my feet. Your feet don't bounce around as much, you have the shortest cable runs, 16 oz bottle holder on top, and more weight forward for heavy aft loads.

Andy, Why do you want to move it?

Before you move it, check your weight and balance for your normal loaded flight operations. 150+ hp Cubs tend to be nose heavy. Moving the battery forward moves the CG further forward. Overall performance is better with the CG towards the rear.

skywagon8a said:

Andy, Why do you want to move it?

Before you move it, check your weight and balance for your normal loaded flight operations. 150+ hp Cubs tend to be nose heavy. Moving the battery forward moves the CG further forward. Overall performance is better with the CG towards the rear.

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I have a PA-18-95 with the original pull type starter, generator, and battery. I’m considering getting rid of the starter for a lightweight sky tech. If so, I may consider a light weight alternator and battery just to simply reduce my empty weight a bit and gain some useful load. Furthermore, I may consider deleting the generator/alternator all together and just going with a battery tender between flights. All the while, I already have the under rear seat storage compartment (under utilized) that can hold a battery and would be very convenient for charging if I delete the gen/alt.

I would agree, I don’t want a nose heavy cub and therefore why I’d like to also keep it under the rear seat. A pic of someone’s install would be great! Thanks!

Worse thing we ever did was move the battery on a 90 hp Super Cub with light weight starter. Didn't have the elevator authority when flying solo which was 90% of the time. Put an SBJ16 battery in the stock location but be my best advice.

Yep, leave it where it is and just replace with a lightweight battery. Most people's advice on here pertains so 150+hp cubs where weight/CG is moving fore/aft a lot more. On your PA-18-95 it's pretty well balanced from the factory (probably the most balanced cub out there) so don't mess with it too much.