Cessna 120-140 Association

6643 wrote: ↑Sat Jun 09, 2018 6:41 pm A 337 is only required for a major repair or major alteration. Ask him to show you where it says changing brands of batteries is a major alteration.

Our PMI was also the inspector for our part 147 school. He always remarked about how many unnecessary 337s were filed. I guess the A&Ps look at it as CYA.

I suppose since Concorde has an STC, and STCs are approved data for major modifications, you could argue that a 337 is required... OTOH, if Concorde had a PMA for that battery to replace the original battery, then a log book entry would be sufficient.

His argument centered around the increased weight making not original equipment equivalent.

8233 wrote: ↑Sat Jun 09, 2018 9:51 pmHis argument centered around the increased weight making not original equipment equivalent.

Well, the Concorde weighs in at 23.5 lbs and item 302 on the aircraft specification is listed at 24 lbs... (so you'll go faster with the original! )

6643 wrote: ↑Sun Jun 10, 2018 6:50 am

8233 wrote: ↑Sat Jun 09, 2018 9:51 pmHis argument centered around the increased weight making not original equipment equivalent.

Well, the Concorde weighs in at 23.5 lbs and item 302 on the aircraft specification is listed at 24 lbs... (so you'll go faster with the original! )

LOL, that's awesome. I should have looked there. I'm going to pull some log information together for him since the battery before the currently installed Gill was a Concorde RG25.

But here is another question for you John. On the Odyssey battery option, clearly you get some useful load back but how does that battery compare performance wise against the RG25-XC?

Thanks

The Concord battery is approved under PMA and TSO for C120/140. See:

http://www.concordebattery.com/otherpdf/finalfaapma.pdf

Even without that, the TCDS is pretty loose regarding the battery, See item 302 of the type certificate - 12V, 24 amp hr.

Larry Lowenkron, A&P
C140A N5641C

8233 wrote: ↑Sun Jun 10, 2018 9:08 am how does that battery compare performance wise against the RG25-XC?

Greater cranking capacity. Less reserve capacity. Weight savings of about 8 lbs.

The reserve capacity of the Odyssey battery does not specify a rate, but the one hour rate is a common measure. The Concorde battery does specify the one hour rate. Assuming both are spec'd at the same rate, the Concord can deliver 24 amps for one hour whereas the Odyssey can deliver 15 amps for one hour. If you're flying hard IFR at night, advantage Concorde.

8175 wrote: ↑Sun Jun 10, 2018 5:38 pm The Concord battery is approved under PMA and TSO for C120/140. See:

http://www.concordebattery.com/otherpdf/finalfaapma.pdf

Even without that, the TCDS is pretty loose regarding the battery, See item 302 of the type certificate - 12V, 24 amp hr.

Larry Lowenkron, A&P
C140A N5641C

Thanks Larry, I sent that over to my IA as well. All I can do is lay out my case and see what he wants to do. I also sent him the example 337 for the Odyssey option that's posted in the library. Either way, I need to get the battery replaced. The Gill installed is shot. I flew the other night and even with all LEDs, etc, by the time I was ready to take off, the radio was making all kinds of weird sounds. Turns out, it was due to the battery. Once I throttled up to a high enough RPM, the generator was generating enough power. I'm also going to get an alternator conversion later this month.

Thanks

6643 wrote: ↑Sun Jun 10, 2018 6:35 pm

8233 wrote: ↑Sun Jun 10, 2018 9:08 am how does that battery compare performance wise against the RG25-XC?

Greater cranking capacity. Less reserve capacity. Weight savings of about 8 lbs.

The reserve capacity of the Odyssey battery does not specify a rate, but the one hour rate is a common measure. The Concorde battery does specify the one hour rate. Assuming both are spec'd at the same rate, the Concord can deliver 24 amps for one hour whereas the Odyssey can deliver 15 amps for one hour. If you're flying hard IFR at night, advantage Concorde.

So basically nothing over and beyond when I did a stare and compare against the specs for both. I see most people say they get quite of bit of lifespan out of the Concordes. Does the Odyssey have similar or could I be replacing it more frequently? I just don't know much about their longevity but i do like the lighter aspect of it. I'm trying to put the bird on a diet anyway.

I installed an Odyssey battery, model PC 625, in a Citabria 7GCBC, during the annual, in 2013. Installed the same model PC 625 in a Cessna 120 in 2014. Made a mounting assembly in the original battery location in the 7GCBC. The Cessna 120 battery box was a good fit with two wood blocks for positioning. Completed 337s for each installation, forwarded them to OK City, and they are on file there. No problems. The 2013 battery was replaced this annual in May. Still held a charge, but the owner wanted it changed. Over the years I've seen lawn tractor batteries, motorcycle batteries, car batteries, etc., installed in different planes. I've never had a Gill 12v battery last more than 3 tears. A Concorde RG-25 is in my Cessna 140. Been in there for 6 years.

My Odyssey is about 5 years old. (Logs not handy). Once, when it sat for a few days with the master on, I thought I'd done it in. After several hours on the charger, it was still stone dead and not taking any current. Turns out they like a slightly higher charging voltage (something to consider; an adjustable voltage regulator might help). Anyhow, after a couple of days on the charger all is well again.

Another advantage to the Odyssey, if you have long periods of inactivity, The Odyssey is much less prone to self discharge.

Oh, yeah, and the Concorde is now stupid expensive...

(Avoid the lawn tractor batteries; they are not spill proof!)

If you can run the engine RPM up enough to get the reverse current relay to close, you'll have better luck with the radios while taxiing. Of course, the alternator conversion will solve that problem, too. Which one are you looking at?

6643 wrote: ↑Mon Jun 11, 2018 5:40 am Oh, yeah, and the Concorde is now stupid expensive...

(Avoid the lawn tractor batteries; they are not spill proof!)

If you can run the engine RPM up enough to get the reverse current relay to close, you'll have better luck with the radios while taxiing. Of course, the alternator conversion will solve that problem, too. Which one are you looking at?

Agreed on the price and the lawn tractor batteries. I'm looking at the Plane-Power option for alternator conversion.