Corrosion risk and location history

4RNB

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What planes are at higher risk? I've heard to be cautious of Florida, is that for any where in the state? Any specific rules to follow? Or just use common sense with visual inspections?

Situation is I am reviewing log books on a plane that had work done at Orlando Executive.

Thank you.
 
Work done in FL is not the same as being based there for years.
 
This chart is pretty accurate for aircraft susceptibility to corrosion. There are those that will say “well I live in Florida and my plane doesn’t have corrosion.” That’s great and if they say their aircraft doesn’t have corrosion, it’s either been hangared and well cared for or they’re someone that doesn’t have attention to detail and really know the insides of their aircraft.

In my experience, having lived in Florida, bought cars and an airplane (Velocity) from Florida, corrosion is a definite concern. I bought a Fiero from a dealer in Tampa who told me my car was a 9 out of 10. No, the frame had a whole bunch of rust on it. My DeLorean was bought in Orlando but spent its life in Tampa. Was told “oh this is a car from DMC and we don’t sell rusted cars.” Nope, has plenty of rust on the underside. Not on the epoxy chasis or obviously the stainless steel, but it’s got rust. My Velocity sat on the ramp at Sebastian for a year. Hardware rusted, engine rust. Had to have all that replaced / overhauled within a couple of years. Grandmother’s Honda Civic, her engine was a rusted / corroded mess.

It’s only common sense. Combine heat, humidity, and salt and you have perfect conditions for corrosion. Another reason why is some cases in the military you’ll see a “bird bath” at coastal bases or you’ll see an engine inspections in the flight manual when flying over salt water.

https://numericalmethodsnikhil.blogspot.com/2019/02/factors-affecting-corrosion-in-aircraft.html
 
This chart is pretty accurate for aircraft susceptibility to corrosion. There are those that will say “well I live in Florida and my plane doesn’t have corrosion.” That’s great and if they say their aircraft doesn’t have corrosion, it’s either been hangared and well cared for or they’re someone that doesn’t have attention to detail and really know the insides of their aircraft.

In my experience, having lived in Florida, bought cars and an airplane (Velocity) from Florida, corrosion is a definite concern. I bought a Fiero from a dealer in Tampa who told me my car was a 9 out of 10. No, the frame had a whole bunch of rust on it. My DeLorean was bought in Orlando but spent its life in Tampa. Was told “oh this is a car from DMC and we don’t sell rusted cars.” Nope, has plenty of rust on the underside. Not on the epoxy chasis or obviously the stainless steel, but it’s got rust. My Velocity sat on the ramp at Sebastian for a year. Hardware rusted, engine rust. Had to have all that replaced / overhauled within a couple of years. Grandmother’s Honda Civic, her engine was a rusted / corroded mess.

It’s only common sense. Combine heat, humidity, and salt and you have perfect conditions for corrosion. Another reason why is some cases in the military you’ll see a “bird bath” at coastal bases or you’ll see an engine inspections in the flight manual when flying over salt water.

https://numericalmethodsnikhil.blogspot.com/2019/02/factors-affecting-corrosion-in-aircraft.html

do you know more about that site or from where that figure came from?
 
Florida definitely is cause for concern, but not necessarily a reason for a "no-go" but make sure the inspection is thorough.

I have a friend who bought one site unseen in Florida and he ended up having bought an engine, some old worthless avionics and a pile of scrap aluminum once the wing spar was looked at and was in bad condition. So threat is real, but really all those same things should be looked at even if the bird is sitting in Nebraska....

Especially with the age of most of our birds, it might be for sale in Nebraska but could have lived on a private strip on a 10 acre island off a coast for 30 years before it moved to dry-salt free Nebraska...
 
I flew to an airport near Miami to look at a C-172. It was very bad…so bad I would even consider flying it. The tail was blistered with corrosion. It obviously sat outside. I think if you look at it you’ll be able to tell if it’s a basket case.
 
What planes are at higher risk?
Any aircraft that didn't have some sort of corrosion preventative used on a regular basis would be more susceptible to corrosion.
I've heard to be cautious of Florida, is that for any where in the state?
Basically any state where an aircraft could be based within 50 miles of saltwater. 50 miles is a common distance used by OEMs when discussing these issues. Urban, industrial areas can also have a corrosive affect on bare metal as well.
Any specific rules to follow? Or just use common sense with visual inspections?
Common sense and the understanding of those who look at the aircraft of the importance in checking for corrosion. One of which should be the mechanic you plan use to maintain the aircraft. I've spent my entire career around the GOM and have found that it isn't the specific location that is an issue as it is how that owner and past owners maintained that aircraft is the deciding factor when addressing corrosion issues.
 
I'd be concerned with the amount of corrosion on an aircraft that spent time along any coast, but the western US desert has its own corrosion issues too. Physical condition is one of the most important factors with an aircraft transaction; I would not pass up an aircraft that has been stored/operated in a coastal or desert environment but it needs to be inspected to know what you're getting.
 
Here's the map from the Cessna SIDs now incorporated into the Service Manuals
 

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Situation is I am reviewing log books on a plane that had work done at Orlando Executive.

You didn't say it was based in FL
 
Just as important is whether the plane was hangared or sitting out on the ramp.
 
A painted exterior is more resistant to corrosion than the bare aluminum interior. A few months ago some fellow posted here about the Cherokee (I think it was) he bought, and at the first annual there was severe corrosion found in the tailcone. And I mean SEVERE. I think he had to get a lawyer, and the airplane was likely junked. It almost looked like it had been submerged in saltwater.

If the paint is blistered, it's likely much worse inside. Hardly worth looking any further. Pop the blister and see what the metal looks like underneath it. Might be shocking.
 
It also depends on whether the entire airframe is corrosion-resistant paint treated or not. There are a lot of Cessnas from the 1970s that don't have internals painted with zinc chromate paint. Those need to be regularly fogged, thoroughly, with Corrosion-X, ACF-50 or similar to mitigate against corrosion.

The map posted with California is misleading. The true "coastal" airports, within just a few miles of the coast, are most susceptible. Once you get 10 miles or more inland the coastal salt influence is greatly reduced.

I once looked a plane based in Carlsbad, CA. It had nice fresh paint, but every single piece of chrome on it (door handles, etc.) was crusted in green corrosion. I moved on, quickly.
 
I'd not buy a Mooney from Florida for any money. The underlying steel can corrode, and it takes quite the inspection to see it, and quite the repair to fix it. Plenty of airplanes from elsewhere.
 
I'd not buy a Mooney from Florida for any money. The underlying steel can corrode, and it takes quite the inspection to see it, and quite the repair to fix it. Plenty of airplanes from elsewhere.
I hear that citrus juice is really corrosive to a Mooney! :eek:
 
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It also depends on whether the entire airframe is corrosion-resistant paint treated or not. There are a lot of Cessnas from the 1970s that don't have internals painted with zinc chromate paint. Those need to be regularly fogged, thoroughly, with Corrosion-X, ACF-50 or similar to mitigate against corrosion.

The map posted with California is misleading. The true "coastal" airports, within just a few miles of the coast, are most susceptible. Once you get 10 miles or more inland the coastal salt influence is greatly reduced.

I once looked a plane based in Carlsbad, CA. It had nice fresh paint, but every single piece of chrome on it (door handles, etc.) was crusted in green corrosion. I moved on, quickly.

Not aviation experience based, but having lived in the SE within about 20 miles or less of the ocean/salt water for about 43 years now in Florida and North Carolina(well <1 of those years was in Atlanta), I'd say that's true everywhere on that map. I know there is some salt affect at say 10 miles it's generally only going to be occasional/conditional and is very slight...nearly just theoretical. I'd offer a guess that the areas on that corrosion map are as much or more to do with typical humidity than anything else...
Just hacking at a guess number, I'd say you generally see the corrosion on home air conditioners and other things within maybe 5 miles of the ocean...and the severe/fast stuff much closer than that
 
Keep in mind its not just where you park the aircraft but where you operate it. Most of those OEM maps are also geared toward operating in the "salt-laden" areas. Simply parking an aircraft in a hangar doesn't protect it from corrosion as it gets more exposure to the elements when flying. So following the recommendations like washing the aircraft with fresh water after each flight, maintaining the corrosion preventatives, keeping the painted areas up to spec, etc. is what is needed to reduce the likelihood of corrosion. There are plenty of anodes and cathodes on an aircraft just waiting for an electrolyte to hook them up. Unfortunately a good number of people prefer to address these issues only at annual time which in some cases is too late.
 
I'd not buy a Mooney from Florida for any money. The underlying steel can corrode, and it takes quite the inspection to see it, and quite the repair to fix it. Plenty of airplanes from elsewhere.
Nonsense.
 
So following the recommendations like washing the aircraft with fresh water after each flight

I lived in Florida, Daytona Beach, did time at ERAU. Not one of their AC was ever washed after each flight. Been to lots of airports in FL, never seen this done.

My BD was on the West Coast (CA, WA) since the late 70's and the bare metal is fine.

I'm sure if you submerge Al in salt water for a few days it will do bad things.
 
I live in Tampa. My airplane is hangared. My boat, which is operated exclusively in salt water, sits on a trailer at my house. My motorcycles stay in the garage. My truck sits in the driveway. All of my vehicles, to include my plane sit 24/7 less than 1 mile from salt water even when I’m at work.. From my experience, the Florida sun is waaaayyy more of a threat (heat and UV) to any vehicle than salt. Hangaring (a good cover in the case of my boat) is huge for eliminating any sun related issues. Frequent operation and routine preventative maintenance will keep most corrosion issues at bay.

Side note: I do rinse and flush the boat after every outing but I might wash the plane with water maybe once a year.
 
Been to lots of airports in FL, never seen this done.
As I said a good number don't know the recommendations or don't care. I know of over 100 aircraft right now that get washed with freshwater after each day of flight in salt air whether it was 30 minutes or 8 hours strictly for corrosion control. Perhaps if more people in FL did follow those recommendations they could ditch the bad rep when it comes to corrosion and aircraft as shown in this thread. A little bit goes a long way.;)
 
Nonsense.
Sorry Salty, but that is complete BS. You have to take apart the whole interior and get off all the side panels to see any of it. The spar caps can't be repaired, they have to be replaced, spar cap corrosion is a Mooney killer just like you. If other members of the still understructure are corroded the skins have to be removed in order for the steel to be replaced, again big-time repair. Perpurchase inspections usually don't include pulling the whole interior out, heck my mechanic doesn't even do that at annual.
 
I'd not buy a Mooney from Florida for any money. The underlying steel can corrode, and it takes quite the inspection to see it, and quite the repair to fix it. Plenty of airplanes from elsewhere.

Mainly a problem with older models. And it is from water leaking and soaking the insulation, not necessarily salt related.
 
Sorry Salty, but that is complete BS. You have to take apart the whole interior and get off all the side panels to see any of it. The spar caps can't be repaired, they have to be replaced, spar cap corrosion is a Mooney killer just like you. If other members of the still understructure are corroded the skins have to be removed in order for the steel to be replaced, again big-time repair. Perpurchase inspections usually don't include pulling the whole interior out, heck my mechanic doesn't even do that at annual.

And there is a Service Bulletin requiring this inspection on the susceptible models.
 
Significant is not only where it IS; but where it WAS.

Inland regions don’t get a free pass. Some of the worst I’ve seen was in the
Niagara Falls area in the ‘70’s. Wonder why?

Chemical plants, Love Canal, Bell rocket fuel haze drifting across the ramp?

Maybe?

And we haven’t even mentioned mice!
 
Sorry Salty, but that is complete BS. You have to take apart the whole interior and get off all the side panels to see any of it. The spar caps can't be repaired, they have to be replaced, spar cap corrosion is a Mooney killer just like you. If other members of the still understructure are corroded the skins have to be removed in order for the steel to be replaced, again big-time repair. Perpurchase inspections usually don't include pulling the whole interior out, heck my mechanic doesn't even do that at annual.
Yup. Someone sold a Mooney to the flight school, and the steel frame was found to be rotted right out of it. Off to the salvage yard it went.

We bought a Seneca II. One of the mechanics went to climb into it and the step, aft of the right wing and riveted to the aluminum structure, tore right off the airplane. The step was a welded steel assembly, and being against the aluminum for many years resulted in serious, hidden galvanic corrosion.
 
Seems to me the bottom line is get a good inspection and if it's in a corrosion prone area pay the pre-buy guy to go the extra mile.
 
Yup. Someone sold a Mooney to the flight school, and the steel frame was found to be rotted right out of it. Off to the salvage yard it went.

I looked at a Mooney I called "eyesore", the paint was just that bad. Ran OK, even took a flight in it. Panel and interior were basic, nothing to write home about, but functional and clean. But I thought if it looked that rough on the outside, what did it look like on the inside? I saw a couple years later that it had been condemned due to corrosion.

Corrosion isn't limited to the coasts, and whoever said that the insulation was a big culprit had it right. But I'd still look at a coastal Mooney, especially a Florida one, with a very jaundiced eye.
 
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