AFAIK control surface bonding is as much to do with lightning protection as to stop static buildup. Without bonding a lightning strike could weld control surface hinges solid.
My airframe is similar to the TB20 but all control surfaces have bonding straps.
Ted.P wrote:
Without bonding a lightning strike could weld control surface hinges solid.
Never heard of that actually happening – but, if it did, it would surely ruin your whole day ..
Gliders have crashed after control linkages got melted by lighting.
But the radio is more likely affected. People flying “plastic” planes are fairly commonly chasing poor radio range issues. Especially homebuilts.
From here
Peter wrote:
and with a “plastic plane” one pretty well has to
I asked Elixir how they planned to get IFR certification given the carbon fibre construction and the risk of lightning strikes. They said there are two routes, embed something into the carbon fibre that provides lightning protection, or have onboard equipment, such as a stormscope, to allow one to stay away from lightning.
The said the first option was not practical for them, as it would add too much weight, so they were planning to go with the second option.
I presume, but don’t know for sure, that Cirrus and Diamond went for the first route.
derek wrote:
I asked Elixir how they planned to get IFR certification given the carbon fibre construction and the risk of lightning strikes.
In my experience, carbon fiber is very conductive. Found this out the hard way, long story.
Yes; carbon fibre is static “dissipative” but the conductivity is far too low to work for lightning.
The method which gives you both is a metal mesh in the composite. It’s not heavy but it is an extra step in the lay-up of the composite layers, and you have to make sure that contact can be made to it in the finished component. Just having a mesh in a fibreglass (or carbon) panel, which doesn’t connect to anything, is no good.
Peter wrote:
Yes; carbon fibre is static “dissipative”
Is it sufficiently “dissipative” that you don’t need other anti-static measures for the comms?
Probably – if all panels are interconnected, and the connection is continuous all the way to the static wicks.
I would expect an antenna to still need a metal ground plane.
