A complicated question about LiFePO4 batteries, - and switching.

On Friday, July 27, 2018 at 1:21:41 AM UTC-7, Charlie Quebec wrote:
I use a cheap android phone with xcsoar, kept in the side pocket, fully charged. Powered off it can be going in a minute, and using its own GPS.
I have a mechanical Winter as vario backup. You dont get to go solo here without the ability to do a circuit and land with all instruments covered.
Losing power would little to no inconvenience.
A truly independent backup that costs less than $100.

I have a LxNav S3 with the UPS battery pack, which according to specs should give me 8 hours of vario with audio should I lose ship's main bus, and all those pretty glass instruments. Coupled with a JSW, Super Class, wiz wheel it is just like my first 300 hours of xc flying before I purchased the most modern flight computer made, at the time, the B100. I also have a real sectional(s) for the area I fly, and iGlide loaded on a phone zipped into my pants on flight mode.

On Friday, July 27, 2018 at 8:24:30 AM UTC-7, Jonathan St. Cloud wrote:
On Friday, July 27, 2018 at 1:21:41 AM UTC-7, Charlie Quebec wrote:
I use a cheap android phone with xcsoar, kept in the side pocket, fully charged. Powered off it can be going in a minute, and using its own GPS.
I have a mechanical Winter as vario backup. You dont get to go solo here without the ability to do a circuit and land with all instruments covered..
Losing power would little to no inconvenience.
A truly independent backup that costs less than $100.

I have a LxNav S3 with the UPS battery pack, which according to specs should give me 8 hours of vario with audio should I lose ship's main bus, and all those pretty glass instruments. Coupled with a JSW, Super Class, wiz wheel it is just like my first 300 hours of xc flying before I purchased the most modern flight computer made, at the time, the B100. I also have a real sectional(s) for the area I fly, and iGlide loaded on a phone zipped into my pants on flight mode.

I'm using an iPhone X with iGlide as the primary tactical display. If the avionics battery and everything connected to it fries, iGlide simply switches to internal GPS, barometer and battery. It will give a warning about the charge power going out, if you miss that it is seamless enough that you may fly the rest of the day without noticing. The main thing I notice is no more Flarm targets to leech from.

On the other hand, with a well done installation the chances of the whole panel failing should be quite remote. I'v got two independent batteries with two independent supply paths to the power bus - which is the single point of failure but being a solid piece of copper fairly reliable.