I'm looking at a few all-metal kit LSA's, and I'm wondering about corrosion treatment for operating in a maritime environment. I live on the coast of northern Norway, and I think it'd be nice to be able to put the thing on floats and operate it from the ocean. Any tips for corrosion treatment during the build that adds the least amount of weight? Or do I skip it and just make sure to rinse it off well?

If it matters, the most likely candidate is the ICP Savannah S. Iit does everything I need it to and is very well known over here in Norway.

This is one area where weight for corrosion treatment would be the least of my concerns. Make sure you use the best available, don't worry about the weight, worry about coverage.

Kurt

I detest chasing corrosion. Dinitrol is the product I hear about most when talking to a company here in Alberta that prepares Twin Otters for service in the Caribbean and Maldives. ACF-50 and Corrosion X are also well known.

As a builder, I’m sure you’ll want to start by applying primer to all the parts before they go to final assembly. You’ll want primer in every lap between parts. I can make an inquiry as to what they use here on the Twin Otters, but I can nearly guarantee it’s not going to be a waterborne, single part, self etching variety. It’s going to be a detailed process to get it right. You need expert advise. Someone here will know.

Then, you still need to wash it after every day of flying. Kenmore Air Harbour pulls their Beavers out every night and rinses them with a fire hose. They don’t pull the Otters out. Probably too heavy, but they still get a rinse.

After priming, corrosion coatings, and diligent washing, you’re still going to find corrosion from time to time that will require cleaning, coating, treatment, and monitoring. Once you’ve monitored it for a while you’ll almost certainly end up having to change some parts, skins, or worse.

If I really wanted to land in the ocean, I’d be looking for a composite design. It would be amphibious to make it easiest to get on dry land and wash it. Also to be able to store it inland away from salt air. Alternative is keeping it on a fresh water lake.

Good luck! I highly recommend float flying. I’d like to fly the west coast of BC and Alaska, landing where I please, but I doubt I have the diligence to keep my airplane clean enough, and finding corrosion would break my heart.

You'll want to spray parts before assembly with a chromium based epoxy primer. Epoxy primers are not porous as most others. Some porous primers can actually help speed up corrosion. Chromium based epoxies are not readily available in some States here in the US. I'm not sure if it's any easier to get over there. DuPont makes a good one. Last time I purchased some it was from a supplier called Blue Ridge Paint 816-737-2600.

Pinecone wrote:If I really wanted to land in the ocean, I’d be looking for a composite design.

I'm a very green pilot, and it would probably take a while before I get my permission to fly float/seaplane. And since I'm just flying for fun, and at the mercy of my family, it's very likely my first plane would also be my last... I'd like to do it properly then, and know it's ready for what I would want to do in the future. It's also more likely I'd put it on skis before floats, that, combined with the usually high cost of flying boat-type planes is why I'm looking at the all metal ICP Savannah S. It's also very well known in Norway, so there's a bunch of people to ask for advice.

But I came here, because the few people I've talked to who operate their planes from the ocean have not added any kind of treatment to their planes. It might sound weird because of me apparently being clueless, but I am the head of collections at the national aviation museum of norway, and I've seen what a maritime climate can do to aircraft.

EDIT: I say weird, because there are people in aviation who expects me to be an aircraft expert when I'm an academic and my field is museology, and I'm more responsible for administering both the conservateurs and the real aicraft experts.

I am a believer in ACF-50. It is messy but will get in all the nooks and crannies of a plane. The stuff is still weeping through where the skins lap on my Cessna 180 and collects dust. That is good in my opinion.

@Halestorm

That guy would know how to handle this.

180Marty wrote:I am a believer in ACF-50. It is messy but will get in all the nooks and crannies of a plane. The stuff is still weeping through where the skins lap on my Cessna 180 and collects dust. That is good in my opinion.

I agree with you on that. It seems to last the longest.

I’m not a float pilot, my experience is with the corrosive environment we work ag planes in. I’m a fan of CRC products, I started with SP400 but am trying their marine corrosion inhibitor this season. The marine version seems a little thicker than the SP400. I spray every exposed piece of bare metal, stainless camlocs, all hardware, etc. with at least 2 thick coatings. I’ll fog it inside the engine cowling, belly, under the dash, and all wiring. All the circuit breakers and wire ends get a good coating. Any pulleys, hinges, moving parts get sprayed with Permetex white lithium grease. Any steel showing signs of rust in the season gets a coating of rust converter, I think Prevent or something like that is the name brand. Any corrosion on panels during the season is sanded down and sprayed with SEM zinc chromate primer. I don’t like the products like ACF50 because they never dry and remain fluid and tacky, that makes it easy for chemical residue to bond with and travel deep into every crevice. The CRC dries with a waxy surface, and the metal underneath remains clean.

Both of my airframes are 47 years old with 10,000+ hrs and remain in good shape. They’re not the prettiest with brown streaks of corrosion inhibitors all over them, but I’m happy with the results of my effort to keep them clean.

A lot of good stuff here, thanks a lot!

But when buildling, anything else but taking care with priming? And do you apply AC-50 or SP-400 in the inside of the tail cone? That seems like a tricky space to apply anything in a meaningful way. Same goes for the wing. Or does any of the products fog up well enough to reach all the cavities?

I just learned some things from CenterHill. Here is some more info about ACF-50 and how it can be fogged into wings etc.

http://www.acf-50.co.uk/aviation.htm

Topical: Australian Airworthiness Bulletin 02-042, Corrosion Inhibiting Compounds and Effects on Aircraft Structural Joints
https://www.casa.gov.au/file/78206

(URL edited to remove auto-generated download token)

CenterHillAg wrote:.... Both of my airframes are 47 years old with 10,000+ hrs and remain in good shape. They’re not the prettiest with brown streaks of corrosion inhibitors all over them, but I’m happy with the results of my effort to keep them clean.

Off topic, but I'm curious what you're flying?

Ag Cats. One is a turbine and the other is R985 powered.