Corrosion pictures - required treatment?

I don't think a borescope would be required to detect this corrosion issue. I can see an inspection hole in picture #3 and the corrosion obviously is going to be visible in a large number of areas with simply a flashlight and eyeball.

As for culpability of the last mechanic who signed off the annual: who is saying that any of this renders the aircraft unairworthy? You certainly can't determine that based on a handful of blurry pictures from a twenty five dollar "borescope" posted on an internet forum.

Maybe he paid too much for the airplane, obviously he got a lousy pre-buy but let's not jump the gun, condemn the aircraft to the scrap heap and string up the nearest A&P. It's quite possible that with proper treatment and some deft renegotiation this deal could turn out okay. Depending on where it now resides the aircraft still might possibly be capable of outliving many of us here.
 
Exact reason I don't care to work on these airplanes.

That aside, there is a shop that advertises high wing Cessna wing disassembly and repairs for $3k in trade a plane. I have no experience with them.
 
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Tom-D said:
As far as the corrosion, There really isn't any thing you can do about it, except treat it, and leave it alone. If you try to remove it you are simply removing metal that may weaken the structure. You are not going to get all of it, so leave it alone.
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Not true, I don't think. The fluffy corrosion byroducts harbor moisture that keeps the process going. If it isn't cleaned out of there, like cancer, it continues to spread. Leaving it alone sounds like wishful thinking.

Those pictures show some serious corrosion. I would be looking at areas where steel meets aluminum for the really dangerous stuff. Anywhere a bolt or steel bracket is in contact with the aluminum, and there are lots of those. There are long steel plates under the floor on the bulkhead between the front doorposts that carry the wing strut loads and spread them across the bulkhead. The bolts at the wing roots and each end of the struts. The bolts that retain the spar blocks in the front spar carrythrough. The bolts that retain the stabilizer and fin. Engine mount bolts. Lots of nasty places. There's also the main spar joint at the wing strut, where laminated aluminum plates get corrosion under them, weakening the spar.

I'd be taking that airplane apart to get pictures to challenge the prebuy or annual inspection, whichever it was.

Dan
 
Can somebody recommend a lawyer who has experience in this field?

I believe the next steps will be to discuss the legal options and to get the plane inspected by an air frame expert, who creates a written report.

This is so disappointing, especially because of the almost worthless pre-buy inspection. With the knowledge I have today, I could have done it better myself. :(

I wonder, how many people get screwed over like this, but never find out about it until a few years later the issue becomes so severe that rivets start to pop. :mad: Sometimes ignorance is bliss - without the inspection camera, I would be a fat and happy guy, putting along in his 172... :redface:
 
Dan Thomas said:
Not true, I don't think. The fluffy corrosion byroducts harbor moisture that keeps the process going. If it isn't cleaned out of there, like cancer, it continues to spread. Leaving it alone sounds like wishful thinking.

Those pictures show some serious corrosion. I would be looking at areas where steel meets aluminum for the really dangerous stuff. Anywhere a bolt or steel bracket is in contact with the aluminum, and there are lots of those. There are long steel plates under the floor on the bulkhead between the front doorposts that carry the wing strut loads and spread them across the bulkhead. The bolts at the wing roots and each end of the struts. The bolts that retain the spar blocks in the front spar carrythrough. The bolts that retain the stabilizer and fin. Engine mount bolts. Lots of nasty places. There's also the main spar joint at the wing strut, where laminated aluminum plates get corrosion under them, weakening the spar.

I'd be taking that airplane apart to get pictures to challenge the prebuy or annual inspection, whichever it was.

Dan
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IOWs you'd scrap the aircraft, because there isn't a early 172 that is worth the cost of doing what you suggest.
 
German guy said:
This is so disappointing, especially because of the almost worthless pre-buy inspection. With the knowledge I have today, I could have done it better myself. :(
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That's is what I've been advocating and advising here for years, but who listens?

get smart prior to buying then do the pre-buy your self.
 
German guy said:
Can somebody recommend a lawyer who has experience in this field?

I believe the next steps will be to discuss the legal options and to get the plane inspected by an air frame expert, who creates a written report.

This is so disappointing, especially because of the almost worthless pre-buy inspection. With the knowledge I have today, I could have done it better myself. :(

I wonder, how many people get screwed over like this, but never find out about it until a few years later the issue becomes so severe that rivets start to pop. :mad: Sometimes ignorance is bliss - without the inspection camera, I would be a fat and happy guy, putting along in his 172... :redface:
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Who paid for the pre buy??? You, or the seller?:dunno:
 
Tom-D said:
That's is what I've been advocating and advising here for years, but who listens?

get smart prior to buying then do the pre-buy your self.
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Actually, this is exactly what I was trying to do. I did lots of research, ordered the FAA stuff and ran a title search. Because of my zero experience with buying / owning airplanes, we (my wife and I) however felt that it is wise to let professionals take care of the inspection of the aircraft.


N801BH said:
Who paid for the pre buy??? You, or the seller?:dunno:
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We did. We also consciously chose the Cessna Center in Daytona Beach, because we thought that they should have the most experience and training with Cessnas, including structural repairs. Well.... :rolleyes2: :rolleyes:

Another thing they did not find during the pre-buy was the inop compass. It was discovered 'accidentally' only a few days before we picked up the plane. On one hand not that big of a deal, on the other hand this and the other pretty obvious issues they did not find, besides of the corrosion, speak volumes about the quality of their work.

We did certainly not expect a like new plane. But we wanted a report with all the glitches, especially if they are expensive to fix, so that we could make an educated decision. This is what pre-buy inspections are there for, right?
 
Okay so before we grounded this Cessna and begin the process of scrapping it and determining how bad it is, get an A&P to look at it. I think you'd be hard pressed to find an airplane thats older than 15 years old, that doesnt have some corrosion in it. Your A&P may take a look, give a laugh, and tell you to get it treated for corrosion. My 1956 has corrosion as well.

Cant expect an older plane to not have some flaws. Anything you post on here is going to result in doom and gloom if its maintenance related. Hell, there's a 3+ page thread on the legality of LED lights of all things. I'm not doubting any credentials here but none of the e-experts here can give an 100% reliable opinion. Get someone to give it a look who is qualified and I bet you'll get something like "Yeah youve got some corrosion, you should get it treated but I wouldnt worry about it too much".

Now to the fact that it was missed during a pre-buy and the compass was also missed.... if it was a Cessna service center, maybe you can raise the issue somewhere, get some of your money back or something, but I wouldnt call it a mistake to buy yet.

Now, in my opinion, you should go apologize to her for being unfaithful and take her up flying for a bit. I bet you'll find she still flies okay.
 
bnt83 said:
http://www.pilotsofamerica.com/forum/showthread.php?t=81494&highlight=prebuy
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Yep, I remember this thread and understand that some A&Ps might not find pre-buys worth the potential trouble.

Then again, the Cessna Center accepted to do the pre-buy, specifically confirmed that they will look for corrosion, but did not even find the corrosion directly next to the inspection holes?

I am not complaining about a tire loosing air 3 years after the pre-buy inspection, but about quite obvious corrosion and a pre-buy inspection which was completed on 04/01/2015.
 
German guy said:
Yep, I remember this thread and understand that some A&Ps might not find pre-buys worth the potential trouble.

Then again, the Cessna Center accepted to do the pre-buy, specifically confirmed that they will look for corrosion, but did not even find the corrosion directly next to the inspection holes?

I am not complaining about a tire loosing air 3 years after the pre-buy inspection, but about quite obvious corrosion and a pre-buy inspection which was completed on 04/01/2015.
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I think you have valid concerns and hope you come away happy in the end.
 
German guy said:
Yep, I remember this thread and understand that some A&Ps might not find pre-buys worth the potential trouble.

Then again, the Cessna Center accepted to do the pre-buy, specifically confirmed that they will look for corrosion, but did not even find the corrosion directly next to the inspection holes?

I am not complaining about a tire loosing air 3 years after the pre-buy inspection, but about quite obvious corrosion and a pre-buy inspection which was completed on 04/01/2015.
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I personally think you have a valid concern and legal arguement....

The Daytona Cessna Service Center has some serious explaining to do... Or they can buy the plane from you and add it to their inventory...
 
gitmo234 said:
...get an A&P to look at it...
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I agree. Posting some blurry pictures on an internet forum is a recipe for a stomach ache. It seems fairly apparent that you got burned on the pre-buy but don't let that sour you on all professionals in the industry, there are good people out there.

BTW - had to run out to the back yard just now as a B-24 flew over my house at 800 feet. Probably headed for KCCR, must be some sort on Memorial Day thing going on.
 
German guy said:
Actually, this is exactly what I was trying to do. I did lots of research, ordered the FAA stuff and ran a title search. Because of my zero experience with buying / owning airplanes, we (my wife and I) however felt that it is wise to let professionals take care of the inspection of the aircraft.









We did. We also consciously chose the Cessna Center in Daytona Beach, because we thought that they should have the most experience and training with Cessnas, including structural repairs. Well.... :rolleyes2: :rolleyes:



Another thing they did not find during the pre-buy was the inop compass. It was discovered 'accidentally' only a few days before we picked up the plane. On one hand not that big of a deal, on the other hand this and the other pretty obvious issues they did not find, besides of the corrosion, speak volumes about the quality of their work.



We did certainly not expect a like new plane. But we wanted a report with all the glitches, especially if they are expensive to fix, so that we could make an educated decision. This is what pre-buy inspections are there for, right?
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Out of curiosity, did you ask them to do a 'pre-buy' or ask for an annual inspection as a pre-purchase inspection?
 
gitmo234 said:
Okay so before we grounded this Cessna and begin the process of scrapping it and determining how bad it is, get an A&P to look at it. I think you'd be hard pressed to find an airplane thats older than 15 years old, that doesnt have some corrosion in it. Your A&P may take a look, give a laugh, and tell you to get it treated for corrosion.

[...]

Cant expect an older plane to not have some flaws. Anything you post on here is going to result in doom and gloom if its maintenance related.

[...]

Get someone to give it a look who is qualified and I bet you'll get something like "Yeah youve got some corrosion, you should get it treated but I wouldnt worry about it too much".

Now to the fact that it was missed during a pre-buy and the compass was also missed.... if it was a Cessna service center, maybe you can raise the issue somewhere, get some of your money back or something, [...]
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As I said - I certainly do not expect an almost 50 year old plane to be completely flawless. But I would have expected to find at least the bigger issues in the pre-buy report. We also simply replaced the torque link bushings, without asking the Cessna center for a reimbursement. Still though, something so obvious and common should have been found by them.

Regarding doom and gloom, e-experts and local A&Ps. On one hand I agree with you that sometimes things get blown of proportion here at PoA. On the other hand some of the people on PoA and also here in this thread have quite a history of valuable contributions to the forum in which they showcased their experience. Why should a local A&P, of whom I do not now much more other than a few local pilots seem to be happy with him and that he claims to have lots of experience, necessarily provide more valuable advice than somebody on PoA? Would it be wise to ignore the advise of somebody, who has a track record with the repair of older aircraft, only because he sits on the other side of the screen, but to follow the recommendation of a local A&P who never did any major work on airframes? As I said - one of our local A&Ps suggested yesterday, that we shouldn't worry, as the corrosion is only on the surface, but that we should treat it with CorrosionX. While this would have indeed be the most pleasant solution to our problem, I wanted to become more educated on this issue.

The Cessna Center suggested that we should install a 180 hp engine, because the O-300 is crap and a poor design and that this would be absolutely worthhile because the plane is in such a good condition. Sounds like great 'real world' advice... :rolleyes2:

Also - if we want to have at least a slight chance to make the Cessna Center buy our plane or to send us a check, we will have to act now. The longer we wait, the more questionable will it be whether the condition already existed when they did the pre-buy. In a year or two, it will be too late.

What I usually do is to speak with somebody local, search / ask PoA, do my own research and then make up my own minds. Often this is an iterative process. I always take opinions with a grain of salt, but usually take them into consideration or use them as a stimulus for further research. I get regularly surprised to learn about things of which I don't even know that I don't know about them. :redface:

I learned so many thing about aviation here on PoA, that I wonder how people can do without. Sometimes it is something as simple as that somebody posts a link to an interesting article.
 
Fearless Tower said:
Out of curiosity, did you ask them to do a 'pre-buy' or ask for an annual inspection as a pre-purchase inspection?
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Yes, I asked them to do a pre-buy inspection.
This was also the topic of all of our e-mails, what they said in their e-mail 'Prebuy is complete. Attached are the results.' and what was stated in the report itself 'Action Taken: Performed a pre-buy inspection.'


Before we take her up again, I'll inspect, together with an A&P, the really important bolts, as suggested by Dan Thomas.
 
I'm not saying dont seek a remedy from the Cessna Center at all, but I advocate an in-person look. You're going to have a regular A&P anyway, right? Sounds like a chance for him to get to know the airplane.

Why? because they can put hands on, see the full picture and do a full assessment. There are some good contributions here, but none of them will ever replace an in person look. If you wouldnt buy an airplane based on the online advice here, you shouldnt make big decisions based on them alone either.

About half of the online posts said my plane was worthless when I was going through the pre-buy, so I got a second...and a third...and a fourth opinion (at my expense) on the results. To this day I continue to get comments on how good of a deal it was and how good the condition is.

As to the upgrade to the engine...that sounds like a sales pitch. My O-300 seems to be just fine. They have their "unique" points, but I have no complaints. People either swear by them or hate them....

Until you've got someone with hands and eyes on, you cant take stuff here as much more than speculation.

Financially speaking, I think you'd spend more time and money on a lawyer than what you'd get back.
 
Actually... now that I'm thinking about it... You may be better off complaining a bit to Cessna or the service center itself and trying to get a free corrosion treatment out of it as well as the compass fixed.
 
@gitmo234:

Ahh, OK. I must have misunderstood you. Sorry.
Yes, I will of course also look over it with a local A&P and not only rely on this discussion. Still, this discussion will help me to ask the right questions. We will at least check the bolts which hold the wings and the stabilizers attached. Regarding the 'surface corrosion', I am however leaning towards using an airframe shop or to at least search for an A&P with proven experience in this field.
 
No worries here. You sound a lot like me though. I spent over a year looking for what was wrong. I just couldnt believe nothing was wrong. I did find small things here and there...or some things that to me didnt seem right. The old timers and the A&Ps would tell me its fine but I couldnt believe it. I still catch myself doing that.

Lets hope thats more of the case than anything else.
 
bnt83 said:
More corrosion in cessnas

https://m.youtube.com/watch?v=Tat9gpqlUwg
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Best part of building an experimental is to be able to introduce anti corrosion coatings to mating surfaces.....

On my plane.... EVERY joint got treated by Zinc Chromate products on ALL surfaces before they were fastened together.... Sure it took a bit longer, but it will outlast me, the next owner and the one after that...

Production aircraft just slap it together, call it good enough and silently hope it corrodes so they can sell you another plane in 20 years.....:mad2::mad:..
 
German guy said:
Before we take her up again, I'll inspect, together with an A&P, the really important bolts, as suggested by Dan Thomas.
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The really important stuff is the large rivets that holds the top of the door posts to the wing spar carry thru.

they located above and behind and outboard of the visors.

The last ones I replaced the bill was 35k. Wings must be removed, top cabin skin must come off, the carry thru replaced as well as the door posts.
 
N801BH said:
Best part of building an experimental is to be able to introduce anti corrosion coatings to mating surfaces..... [...]
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...and so many things more. I really like experimentals.
Btw.: I watched your videos, as well as the one by Backcountrypilot about your 801 on Youtube. Very nice. :yes:

Tom-D said:
The really important stuff is the large rivets that holds the top of the door posts to the wing spar carry thru.

they located above and behind and outboard of the visors. [...]
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Thank you. I just learned that a very respected A&P of our EAA chapter has also quite some experience with corrosion and its treatment. He also owned multiple older 172s.
We will meet tomorrow and inspect the areas I found, as well as the bolts and rivets which are critical to keeping the wings / tail feathers attached.
 
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Tom-D said:
IOWs you'd scrap the aircraft, because there isn't a early 172 that is worth the cost of doing what you suggest.
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Well, when there's so much obvious evidence of serious corrosion, what do you do? More than one 172 (and many other airplanes) has been scrapped when this sort of thing turns out to be an expensive mess. The alternative, for a mechanic, is to sign it off and let it fly away and lay awake at night wondering when some part of that thing is going to let go. As the fleet ages, it's bound to start happening.

The restart Cessnas ('96 and on) are primed inside and out before assembly. They'll last much longer. Good primer, too, not the stuff found in older floatplane airframes that flakes off with age.

Dan
 
German guy said:
...and so many things more. I really like experimentals.
Btw.: I watched your videos, as well as the one by Backcountrypilot about your 801 on Youtube. Very nice. :yes:



Thank you. I just learned that a very respected A&P in our EAA chapter has also quite some experience with corrosion and its treatment. He also owned multiple older 172s.
We will meet tomorrow and inspect the areas I found, as well as the bolts and rivets which are critical to keeping the wings / tail feathers attached.
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Look for rusty bolts with corrosion on the aluminum around them. The aluminum suffers far more than the bolt, and can end up thin and rotten from the electrolysis that has been happening. The bolt might hold, but the surrounding aluminum can't take the loads.

While you have the stabilizer/fin fairings off, look at the forward stab spar. There's a large lightening hole in the center, through which the trim cables pass, and that hole gets cracks radiating outward from it, caused by excessive flexing when people push down on the stab to raise the nosewheel to turn the airplane. It puts way more load on that spar than it was designed to handle; the stab's loads are centered closer to its aft spar, which is far heavier. Cessna forbids pushing down on that stab.

See page 2: http://www.faa.gov/aircraft/safety/alerts/aviation_maintenance/media/2004/2004_11_Alert.pdf

Dan
 
Stewartb said:
Reports like this one give merit the the Cessna SID. Oliver should read it for general knowledge if nothing else.

https://support.cessna.com/custsupt/dynamic/dynamic.jsp?dynVal=240
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Thank you, very interesting, albeit a little bit terrifying. I could however not access the presentation through the link you posted, as an account was required, but found a direct link in an AOPA article: http://textron.vo.llnwd.net/o25/CES/releases/CessnaSID.zip

Hard to believe that all those crappy flight training / time building planes get regularly inspected in accordance with these requirements recommendations and that appropriate action will be taken, if something is found. :dunno:
 
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