cruiserflyer Posted December 18 Report Posted December 18 OK folks, what does this switch do? I was poking around in the avionics bay trying to figure out why my altitude hold does not work and found this switch. I tried following the wires by tugging on them, but I lost track of what they go to. Any suggestions are welcome. I have B5 Brittain auto pilot which will follow a heading so that part is working. I was able to confirm it will throw the altitude hold solenoid by checking with a meter, but it does not appear to work in flight. I thought this switch might have something to do with it but when looking over the manual I could find no such switch. So I guess it is for something else, maybe a GPS annunciator but also not sure. The "BC" written on the side also defies my explanation at the moment. Also this connector next to it is also a mystery.ch for?
N201MKTurbo Posted December 18 Report Posted December 18 Well, it is not factory. The soldering is not up to snuff and the factory wouldn’t use a DPDT switch when a SPST switch would do. So, it is a field mod done by somebody for some reason. So, you need to find the one who did it.
Slick Nick Posted December 18 Report Posted December 18 What do the labels on the wires say? Try and cross reference with the wiring diagram.
Utah20Gflyer Posted December 18 Report Posted December 18 Looks like a self destruct switch, but the only way to find out for sure is……………
DCarlton Posted December 18 Report Posted December 18 My Brittain system has a small toggle switch and a light to turn the DG heading track function on and off.
cliffy Posted December 18 Report Posted December 18 Pure guess but- Back Course switch? You have to follow the wires to see where they go. Maybe no where and part of an old install not removed. Also part of my guess Happens all the time.
skykrawler Posted December 18 Report Posted December 18 Usually there is a hint that can be found in a log entry or a 337 describing an installation. Nobody here has a clue about what's in your panel.
TaildraggerPilot Posted December 18 Report Posted December 18 A back course switch has some traction here. Some old and simple autopilots need the course polarity (+\-) switched from the CDI to properly track. As for the connector, a picture of what it looks like from the front would b helpful. 1
Echo Posted December 18 Report Posted December 18 That’s the Berry Manilow music switch. No longer needed. 1
gwav8or Posted December 18 Report Posted December 18 Could it be for the ejection seat or the parachute? /s
N201MKTurbo Posted December 18 Report Posted December 18 The switch has heat shrink on the wires to keep them from shorting to each other or to other things like ground. Yet with the switch in its pictured position, the center conductor is connected to the uninsulated terminal on the right. So be careful where you put that switch.
Slick Nick Posted December 18 Report Posted December 18 the switch looks like it has "PC" written on it? Maybe that's a toggle switch and light for the old positive control system, as opposed to having a momentary pushbutton.
cruiserflyer Posted December 18 Author Report Posted December 18 2 minutes ago, Slick Nick said: the switch looks like it has "PC" written on it? Maybe that's a toggle switch and light for the old positive control system, as opposed to having a momentary pushbutton. When I was holding it in my hand, it looks to me like "BC", but interesting thought.
cruiserflyer Posted December 18 Author Report Posted December 18 39 minutes ago, TaildraggerPilot said: A back course switch has some traction here. Some old and simple autopilots need the course polarity (+\-) switched from the CDI to properly track. As for the connector, a picture of what it looks like from the front would b helpful. I think you're right. And I'll get another pic but it looks like some kind of DC connecter, with a center pin.
Echo Posted December 18 Report Posted December 18 Igor is currently selling the electric PC disconnect on Mooney space. It is an electric solenoid and generally had a toggle switch on the new style yolk but could've been in the panel. It could've been for that but I don't think so as the part on the other end is wonky looking? The suspense is killing me lol. I gots to know. (Dirty Harry quote)
Jackk Posted December 18 Report Posted December 18 Could be a kill switch fo mags or something? On most planes I’ve seen a hidden switch it was to prevent folks in places like Mexico for stealing it 1
kortopates Posted December 19 Report Posted December 19 Have you tried looking through the logbook for its installation or asking the previous owner? It can’t be factory and if it’s not logged I’d be pulling it.It can’t be for anything you would need while flying, like backcourse switch or PC switch, or it wouldn’t be installed in the avionics bay.Sent from my iPhone using Tapatalk 1
kortopates Posted December 19 Report Posted December 19 Could be a kill switch fo mags or something? On most planes I’ve seen a hidden switch it was to prevent folks in places like Mexico for stealing it Very true, but only big Cessna’s get stolen south of the border but i do know of a C182 that was stolen as a consolation prize after they couldn’t figure out how to start a C210 with such a switch they took the 182 parked next to it.But i don’t think the cartel has ever had a need for a Mooney!Sent from my iPhone using Tapatalk
cruiserflyer Posted December 19 Author Report Posted December 19 13 minutes ago, kortopates said: Have you tried looking through the logbook for its installation or asking the previous owner? It can’t be factory and if it’s not logged I’d be pulling it. It can’t be for anything you would need while flying, like backcourse switch or PC switch, or it wouldn’t be installed in the avionics bay. Sent from my iPhone using Tapatalk Hey Paul! All my previous logbook sweeps were looking for other things, I'll have to do a deep dive looking for this. The previous owner, while a great guy, hasn't proven very knowledge about these things. If I can't find an entry, I'll remove it with my A&P. I have to figure out why the altitude hold isn't working so I've got more rolling up my sleeves to do anyway. 1
cruiserflyer Posted December 19 Author Report Posted December 19 Well Mooneys scare even cartel pilots.... Cool. 6 minutes ago, kortopates said: Very true, but only big Cessna’s get stolen south of the border but i do know of a C182 that was stolen as a consolation prize after they couldn’t figure out how to start a C210 with such a switch they took the 182 parked next to it. But i don’t think the cartel has ever had a need for a Mooney! Sent from my iPhone using Tapatalk Well Mooneys scare even cartel pilots.... Cool. 1 1
Fly Boomer Posted December 19 Report Posted December 19 53 minutes ago, kortopates said: It can’t be for anything you would need while flying, like backcourse switch or PC switch, or it wouldn’t be installed in the avionics bay. I think there may be some confusion regarding what the OP is calling the "avionics bay". I suspect that you and I would think of the area behind the baggage compartment, but there may be another interpretation, that allows that switch to be accessed from the cabin.
cruiserflyer Posted December 19 Author Report Posted December 19 Just now, Fly Boomer said: I think there may be some confusion regarding what the OP is calling the "avionics bay". I suspect that you and I would think of the area behind the baggage compartment, but there may be another interpretation, that allows that switch to be accessed from the cabin. Sorry, I mean in front of the windshield. 1
Fly Boomer Posted December 19 Report Posted December 19 Just now, cruiserflyer said: Sorry, I mean in front of the windshield. I thought that might be the case. Let's see what @kortopates says.
kortopates Posted December 20 Report Posted December 20 I thought that might be the case. Let's see what [mention=7862]kortopates[/mention] says.indeed, not what i was thinking. So that doesn’t eliminate it as having been associated with the panel at some point.I can’t tell what model or year from Tapatalk browser.Sent from my iPhone using Tapatalk 1
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