Control surface bonding

Flying Scotsman · #1 03-04-2012, 01:06 AM

Several threads recently about grounding straps or bonding straps to the control surfaces to prevent issues in IMC or otherwise have led me to ponder...they're not on the plans, nor do the assembly instructions mention them. How many people are doing this, and if they are, why? (Or, has anyone ever had or heard of any issues *without* them)?

Just trying to get a handle on the whole issue...I'm pretty sure a lot of the certificated planes I've flown *didn't* have them, but some did. Why or why not?

#2 03-04-2012, 07:55 AM

High speed airplanes (jets) have them. never seen them on small aircraft. Suspect speed = static build up. Plus they are more likely to spend time in the soup where a static charge exists.

flyboykelly · #3 03-04-2012, 11:59 AM

A major reason for bonding straps on control surfaces is to provide a safe path for electricity to flow during a lightning strike. If the surface isn't bonded there is a risk of the hinges welding together due to arcing from the strike. I had a lightning strike on a crj several years ago and the hs tail tip wasn't bonded properly. It blew clean off the airplane during the event.
You will typically see these straps on single engine cessnas along with static wicks.

Flying Scotsman · #4 03-04-2012, 09:35 PM

So RV's are fairly (by GA standards) high speed, and a number of them are IFR capable and presumably spend time in the clouds.

But so far, only 4% have these straps. Interesting...