SonexBuilders.net

I'm working on sourcing all the parts for my panel and electrical system, and now I'm picking out switches.

I realized looking at a picture I took of the factory B-model last summer, they didn't use any kind of guarded switches, even for critical systems like ignition (see attached photo). Maybe I'm being overly cautious, but it seems possible that you could reach for the trim, hit some turbulence, and accidentally turn the engine off if your hand bumped those switches down!

Has anyone else thought of this and used guarded or pull-to-unlock switches for stuff like ignition or battery master switches?

Like this:
https://www.mcmaster.com/7337K97

Or even little switch guards like this, which would be cheaper:
https://www.steinair.com/product/switch ... ess-steel/

What do you guys think?

I say whatever helps you sleep. Peace of mind is worth it. On a side note though unless I am mistaken in the pic the master under the flaps is for avionic/electrical system. If wired correctly the engine will run without it you just won’t have any electric stuff if you turned it off by accident.
Mark

Yeah true the engine should run without any electrical power, unless you accidentally hit the mags switch off!

I'm working on my electrics, too, and have thought about switch guards a bit. I spotted a type I hadn't seen before, as in the pic below - the red dealee in the middle. Sorry I don't recall where I found the image, nor have I found that type of guard elsewhere. It seems like something that could be pretty easily made in the shop, though possibly out of something a bit thinner, like some .032" or .040". One for each switch.

Every towplane I've flown had non-guarded ignition switches. I'd vote that this is overkill.

The only guarded switches I've ever seen in airplanes (and they are few and far between) are switches that, if flipped, might do something irreversible. I can't think of a switch in my Waiex that, if flipped, would cause a problem that wouldn't be solved by simply switching it back.

I did not have any guarded switches at all when I began flying my Sonex. While bouncing along one day in the midwestern summer air, I accidentally flipped off the Master. While reaching to turn it back on, I got one of the mags.

No big deal.

I do now have my master switch with a guard that has a hole drilled in it for use on the ground. I put my canopy pin in it to prevent anyone from accidentally turning on the master.

I love putting kids in the airplane, and this is just a feel-good safeguard.

Rynoth wrote:The only guarded switches I've ever seen in airplanes (and they are few and far between) are switches that, if flipped, might do something irreversible. I can't think of a switch in my Waiex that, if flipped, would cause a problem that wouldn't be solved by simply switching it back.

Like weapons. Or hoist cut. You should definitely guard those ones.

If you kill the engine by shutting all the ignition off, like in the pattern, will it fire right back up when you turn everything back on? Will an Aerovee windmill at pattern airspeed? Honest question, I have no idea!

Spaceman wrote:If you kill the engine by shutting all the ignition off, like in the pattern, will it fire right back up when you turn everything back on? Will an Aerovee windmill at pattern airspeed? Honest question, I have no idea!

On mine - yes. It windmills at 70KIAS and does restart. Went up high over the deserted airport while I made that determination!

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My ELT panel switch came guarded.

I put a guard on my Master - but that was more to do with my big hairy left knee having a tendency to flip it on when exiting the aircraft - which was not good for the battery when you left her like that!......