I am getting ready to replace the Concord RG-25 battery with the Odyssey/Hawker SBS J16 battery using a Field Approval on our Husky A-1B-180. The Concord is a 22Ah and the Odyssey/Hawker is a 15 Ah battery. We operate on Wipline 2100a floats. Was wondering if anybody is running the Odyssey battery with the amphibious floats installed and if the 15 Ah battery with be acceptable for the field approval.
Replacing Concord with Odyssey/Hawker battery
- Thread starter jclausen
- Start date
harry harper
Active Member
We did the same w our A-1. Our AME's opinion was that the swap was a log book entry only as the J16 is an approved battery. As always YMMV.
Ak Kurt
Well-Known Member
You should not need a field approval. My local DER and the person he reports to in the FAA says change it out using existing advisory circular guidance. I’m glad I made the switch, using the J16.
I will say though, it is going to move your CG forward, might not be desirable on amphib floats flying solo.
Kurt
I will say though, it is going to move your CG forward, might not be desirable on amphib floats flying solo.
Kurt
Thanks for the replies. I agree that a logbook entry is all that is needed. My main concern was about the electrical load analysis due to the smaller Ah's on the SBS J-16. We are currently not having any starting issues. We are installing an MT prop so hopefully the W&B will equal out by reducing the amount of weight on the nose.
jkalus
Active Member
It has fewer Ah, however I have parked my plane in Afton, in an unheated hangar for 7-8 months over the winter before and when I go to fly it, it starts in a few turns of the prop. The battery does not significantly lose charge over time.
belloypilot
Active Member
Isn’t that slow discharge rate characteristics of all AGM batteries, including the Concord AGMs?
belloypilot
Active Member
The Concords I’m running are their AGM batteries. I’m no battery expert, but I’m pretty sure I’ve read somewhere they discharge at about 1/3 the rate of a flooded cell battery. I think the secret sauce of these Odyssey batteries is AGM + very thin plates resulting in a lower internal resistance, which translates into higher cold cranking amps. Great if you need juice for the starter, but the lower amp-hour capacity is still a limitation. Whether that matters depends on the individual application and what problem one is trying to solve. No question one would have less time in the event of an in-flight alternator failure if packing 15 AH versus 25, or less tolerance for excessive cranking, but how much that matter is up to each of us I guess. Nice to have choices.
Paul Collins
Active Member
I put the Odyssey battery in but placed it on the firewall. That helped the CG - as well as not putting in the battery frame, cables, etc.
I do notice the battery life is not as long as the Concord.
Paul Collins
N337DP
I do notice the battery life is not as long as the Concord.
Paul Collins
N337DP
Flying Dave
Active Member
What’s the average lifespan??
Earth X weighs about 6 lbs, so big weight savings. Get the vented(certified) one and field approval. Cranks like crazy. Can almost taxi with it cranking!
John