I finally saw what happens when you skip the bonding strip on composite panels

Worked on a Gulfstream GIV last month where the previous shop left out the bonding jumpers on three composite access panels, and I had to track down static discharge issues for two days straight. The difference in static buildup between those panels and the properly bonded ones was night and day, even just sitting on the ramp. How often do you guys actually see corrosion under those bonding tabs when they skip the prep work?

3 comments

3 Comments

alice892mo ago

That night and day difference" really stuck with me. Reminds me of this time I was helping a buddy with his experimental RV-8 and we couldn't figure out why his comms were buzzing like crazy. Turned out he used stainless steel screws on a magnesium oil pan without any anti-seize or isolation, and we spent a whole weekend chasing what we thought was a radio problem. It wasn't until we pulled the pan off and saw the galvanic corrosion eating through the magnesium that it clicked. Have you ever seen that kind of corrosion spread so fast it actually compromised a structural flange?

sullivan.spencer2mo ago

Yeah, magnesium doesn't mess around. Stainless steel's the fast track to a hole in your wallet.

felix_hayes641mo ago

Jump in on that RV-8 story, but I gotta say the oil pan on those is usually aluminum, not magnesium. The difference matters because aluminum and stainless steel still have a big galvanic gap but not as crazy as magnesium would be. You sure it wasn't just the combo of stainless screws and no isolation that did the damage, or was it actually a magnesium pan swap?