Mystery Circuit Breakers?

[NAC]

Hello All,

We have 1965 Turbo Twin that is coming out of its first annual with our shop. Since the plane is going to be used in a part 141 school, we need to know the ins and outs of everything on the plane. There are two CB's that are still a mystery to us and our shop doesn't have a good answer either. The first is a CB labeled Emerg AV PWR. Obviously it is an emergency power circuit for the Avionics, but my question is why is there a circuit breaker there that you pull to energize a system? It is located in the floor CB panel and is the bottom row all the way to the right.

There is also a CB that is on the "Radio Bus" of the floor panel that is bottom row third one from the left labeled "Radio" and has no amperage on it. We can't figure out what it goes to as it doesn't seem to turn anything off when pulled.

Any ideas/information would be greatly appreciated!

Also, thanks to all those who put together the KPDT program it was great to learn more about our Twin!

Thanks

[Eastern]

Shawn,

Can't offer much help on your CB question. The Emerg AV PWR CB is not original. You'll have to look for a wiring diagram from who ever modified the electrical system. Originally that bottom row, far right location is a fuse holder for the clock and ammeter.

Same for your "Radio" CB. Don't know what to tell you. But, pulling up that whole CB panel is not too difficult. It is held in place by 2 screws on the left edge and then rotates upward rather easily (normally). Then you can see if anything goes to the "Radio" CB.

Ain't "vintage" airplanes fun?

George