Control Surface Bonding

[az_gila]

Originally Posted by aerhed

Well, it is connected to the static wicks, in that it provides a path TO the wicks (if installed). .....

It's connected by physics, but apparently not by FAA regulation...

[Flying Scotsman]

So are the physics for an RV different than a Piper?

Seriously...why would some planes have a) bonding straps and/or b) static wicks, and others not?

All of these planes are in the same general class of operating range...all-metal, 125-175 kt range (hopefully a little higher for ours ), electrical system, maybe a mix of vacuum and electronic instrumentation, operating similar environments (VFR, light to moderate IFR)...

[danceskater]

Well, obviously, static wicks strip off a negative charge (electrons) on the aircraft and if the wick is on, say, the elevator, then that elevator would now have a positive charge, would tend to pull electrons off the fusegage and, without bonding, that current flow would be through the rod ends. But, having said that, a requirement for bonding and wicks does not necessarily need to be concurrent and probably is not. Backing up a bit, big picture, it does not seems right to me to have a big piece of metal prowling around the sky with the various parts not securely connected together electrically. The perfect, although extreme, example would be a lightning strike. Without bonding I would expect some welded rod ends. I don't think I want to demonstrate this though. In my field, electronics (not avionics), a less dramatic example, I would think, would be the strange things that avionics might tend to exhibit with stray currents running around through interfaces with some small amount of resistance - such as a rod end. This would not necessarily need to be in a adverse weather situation in order to cause problems. Shipboard (big gray things) installations go to extreme measures to insure that all electrical and electronic equipment is securely bonded to the hull. It is second nature to me.

[az_gila]

Originally Posted by Flying Scotsman

So are the physics for an RV different than a Piper?

Seriously...why would some planes have a) bonding straps and/or b) static wicks, and others not?

All of these planes are in the same general class of operating range...all-metal, 125-175 kt range (hopefully a little higher for ours ), electrical system, maybe a mix of vacuum and electronic instrumentation, operating similar environments (VFR, light to moderate IFR)...

As I noted earlier - they all have bonding straps once FAR part 23 required them for certification.

The wicks are optional...

Even my German fiberglass sailplane (1977 vintage) has every piece of metal in it bonded together - I presume to stop control bearings from welding together in case of a large electric cross potential as mentioned above.