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I share a hangar with John Slade, and have had the pleasure on a number of occasions to ride right-seat with him and experience first-hand what I’m getting at the end of all this labor. On each ride I notice something new, something that changes how I think of the build cycle in terms of the final, flying aircraft. John suggested that I put these thoughts down here, in the hope that other builders might gain some benefit from them. Here goes!

My theme this week is complexity. Flying in a Cozy has changed how I view what’s important and what’s not. I’ve read a recent discussion about switch guards that illustrates this point perfectly. The argument was that it should be made difficult to make mistakes through flipping the wrong switch, and to prevent passengers from doing the same. It’s a perfect topic for me, because I was an adherent – I had all sorts of switch guards and locking toggles in my original panel design.

No.

Way.

The Cozy is SMALL. I’m not talking about Cessna vs. Beech Baron here, I’m talking about Cessna vs. Boeing 747. It’s easy to focus on the width factor, and it’s true that you sit right next to your passenger, legs nearly touching. What you don’t see much talk of, though, is where the panel is. The panel isn’t like a car dashboard – it’s RIGHT in front of you, and it’s not exactly hard to see. You can throw the ‘passengers’ argument out the window immediately (or just throw out the passenger) – if they’re reaching for something, you know it, and you can politely break a finger or two to suggest that they consider another idle-time toy.

As for flipping the wrong switch yourself, most big toggles take a surprising amount of force to actuate, and thus it’s unlikely that you’ll hit the ‘wrong’ switch by simply bumping against it, even due to turbulence. You can’t bump one of these from the side to move it; you have to push it straight up or down.

Switch guards are fine, in principal, but they don’t protect against deliberate actions. Putting one on the arming circuit for a missile is one thing. Putting it on something you flip all the time, like a fuel pump, is a really bad idea. The trouble is, you get USED to flipping it just to manage fuel flow, so after a while the toggle cover becomes just an irritant, not something that makes you think twice. At that point it’s worse than useless. It may even be a hazard, because it may make the pilot clumsy in responding to emergencies, like running a tank dry. That’s not exactly unheard of, and has killed more pilots and planes than hitting the wrong switch ever has.

I think a better answer to address safety concerns is switch segregation.  I plan to put some of the more critical, engine-related switches in front of the pilot’s stick. John has his there, and I’ve discovered that in the Cozy, this is an easily-reached area but also one that is NEVER in a ‘bump into’ zone, because your hand is always on the stick. You would have to either reach across with your right hand and deliberately hit something, or take your hand off the stick – neither action is something that would happen accidentally.

For fuel switches, where you do want rapid access and easy control, I will put them in a group together away from other switches, such as lighting. Beyond that, I think additional time could be better spent in other areas if safety was truly a concern.

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