fibreglass breaks down

[floats]

No reply for FD USA nor FD Germany yet. So I shall try to remove it to see more and also assess the bumps on the stabilizers. As the plane is far from home I want to be sure I take the right tool. It seems to be a hexagonal screw from what I can see on google after searching ISO 7380 M5 x 16. Will regular hex wrench do or it takes extra long

[floats]

Got reply from FD :

Hi Rene,

 

What I see here is not un-common if you use the wrong type of cleaners. In older CT's the foam was susceptible to a PH level found in household cleaners.

 

You must use a PH neutral cleaner to avoid this.

 

We can offer you a 50% discount on replacement parts. Please check your maintenance manual or our website for further care of the plane.

 

 

Sincerely,

 

Dave Armando

 

Director of Maintenance

Flight Design USA

The thing is that I do not use any chemical cleaner .I have only used twice the Neutral PH Composiclean provided by Flight Design with the plane. Besides that I clean the plane early in the morning with the mist that has accumulated on the surfaces and this is perfect as it also removes all the bugs.

[floats]

FD admits it s really bad but seem to put the onus on me or the weather. Does this mean that CT should never stay outside ?

Hi Rene

Please investigate, it's the worst I've seen. Other contaminates can get introduced thru acid rain, etc. In Pennsylvania with the coal plants we've seen some damage.

The Underfin is $ 1,927.50 so to you plus shipping $ 963.75.

The fin is not structural so if the inside is firm you can finish it like any fiberglas part. Be sure to weigh the fin before and after. A 1 pound change is not a concern.

If you'd like anything else please ask.

Sincerely,

 

Dave Armando

Director of Maintenance

[Roger Lee]

Quote:

"The fin is not structural so if the inside is firm you can finish it like any fiberglass part. Be sure to weigh the fin before and after. A 1 pound change is not a concern."

 

 

Remember I said these are carbon fiber on the inside. Fiberglass is too heavy. It isn't structural, but needed for correct flight characteristics. Most people just repair the underfin instead of buying one. The carbon fiber inside should be unaffected and when re-finished you can't ever tell it was done. I use a 6" Tee handle Allen wrench to remove the screws. Be careful not to drop the last 1-2 screws on re-assembly or you have to remove it again to retrieve the screw. Put a little sticky substance on the screw head so it won't fall off.

[floats]

New pictures from the outside and the inside after dismantling the fin. It seems that the gel coat lifted from the fiberglass but as it did not crack it is hard do know if the outside or the inside moved. The picture of the inside shows that the fiberglass has also taken some bumpy shape. I also noticed that one of the attachment screw is not the official M5 x 16 but a Philips head screw and the attachment has been patched up by FD before delivery.

[Roger Lee]

This is the worst case I have ever seen.

[floats]

Flight Design Germany has decided that it was damage from using alkaline material (I only used composiclean twice) and it was my problem.

[Philip Welsch]

I think FD needs to refine its composite technology before it tries to certify an airplane under Part 23. EAA is not going to think kindly of certified aircraft structures (ailerons, stabilators, ventral fins) that deform under normal atmospheric or maintenance conditions. Diamond and Cirrus aircraft don't appear to have these issues. Diamond Aircraft uses aluminum sheet for ventral fins. Does anyone know what the ventral fin on the FD MC is made of? It is also a good thing FD isn't going to use Neuform props on their proposed certified aircraft since that prop dose not tolerate sun light (uv) well.

 

PRW

[Roger Lee]

I believe FD made those changes a while back.

I think FD missed the boat here. If you used a solution bad enough on the under fin most would have used it on the rest of the plane. Yet this is the only area affected. Makes their diagnoses a little suspicious.

I have a couple issues here. First Composiclean washes bugs and dusty dirt just fine, but its garbage for greasy oily dirt. Its PH neutral. It takes a base or alkali solution to desolve grease. Most of our soaps or solvents that clean oily dirt is a base, just like your dish soap. If you don't believe it just buy some PH paper and test your oil and grease cleaners. Thats why we used to hear about the red dish pan hands. an alkali soap cuts grease on the dishes. I use Oil Eater and have been since my CTSW was new to wipe oily areas. I do not wash it with this, I wipe oil or grease of with a rag. The 6 CTSW guys at my field do to and that has been for 6 years. I would bet the majority of the CT owners use some type of cleaner that is an alkali solution. The amount of damage to your under fin is a total loss that would need to bathed or soak it in some way. I have seen rain accumulate and do this same thing. There have been FD foam collapse on other planes over the years that had nothing to do with alkali cleaners. Are there some PH neutral solutions that cuts grease well, maybe, but not most that we would use.

 

 

If something that nasty caused this then why isn't there more damage other places.

[Ed Cesnalis]

...If something that nasty caused this then why isn't there more damage other places.

 

Just guessing; What if #1 the drain hole was plugged and #2 the fin filled with water sourced by acid rain? This could explain why the fin had damage while the rest of the plane didn't

 

Remember that guy from Pennsylvania, 5-6 years ago, he was an instructor and owned an airport and flight school. He had countless posts that CTs flew very badly and couldn't be controlled. I think his issue was water in the fin moving his CG aft. Point is the fin can fill up and the photos are consistent with the damage originating from the interior.

[floats]

Are those spots of bulging fiberglass on different parts of the plane also alkaline related. Dos that compromise the safety of the plane

[Runtoeat]

Collection of water in the fin is not uncommon and this is normally caused by a plugged drain hole. My FBO had a CTSW come in with a deformed under-fin. A plugged drain hole was to blame. This plane also could not be trimmed for pitch. A siginificant amount of water was drained from the fin. I believe that new CTLS' no longer have the large hole on the top side, under the stabilator, in an effort to prevent water from entering the fin. To limit water ingress into my fin, bolus tape has been applied to close off this large hole on the topside of my fin and the drain hole is regularly checked to insure that it remains open.

 

I am currently using Turtle Wax Ice detailer and wax on my CT. It cleans and shines and protects and can be used in sun or shade and on all surfaces, including glass. I've asked for the PH for this product and will report this.

[Roger Lee]

I would advise all to enlarge the small hole on the under fin to drain water if you leave the plane out in the rain. This could happen on a cross country trip. If no hole is there make one. Opening or drilling a hole at the under fin's low point won't hurt a thing.

[Runtoeat]

Turtlewax has responded to my request for Ice pH level.

 

Dick,

Neither Ice Detailer or Ice Wax products are alkaline. I will request MSDS information be emailed to you. (FYI Ice Detailer is about a pH of 5-6. Ice paste wax is oil based and has no pH in water. Ice Liquid wax is a neutral pH.)

Regards,

Mike

 

Michael A Schultz

Sr. V.P. Product Development

Turtle Wax Inc.

 

[Roger Lee]

His damage is so extensive I think it came from the inside. To get that kind of total failure , you would almost have to soak the outside. With just a wipe down, I just don't see it.

[Runtoeat]

Roger, the deformed fin I am familiar with had been holding water for months. This is the ony fin I personally have seen deformed but it is my understanding that this condition is sometimes found in CT's that have trapped water due to a plugged fin drain hole. Agree with your comments about the cause not due to just surface cleaning.

 

The one thing that may be involved here is that this plane is amphibious and has been exposed to Canadian lake water. The lake I have a cottage on here in Michigan will irritate my hands if I have been working on my dock or boat and expose my hands to the lake water for an extended time. Water testing shows our water to have elevated alkalinity. Depending where one is located in this region, calcium carbonate based rocks, such as limestone, can be abundant and can raise the pH of a lake that receives the runoff from these surrounding rock strata. I'm just wondering if long exposure to the spray and wash from amphibious landings on a Canadian lake that may have elevated alkalinity may be the cause for this major degradation?

[Roger Lee]

Hi Dick,

 

So that's where the US shipped all its polluted water, Canada, who would have guessed.

 

I do agree with the water being an issue inside the underfin. It has happened to more than one and a clogged drain hole has happened to several too. It could be just while you are traveling and it rains. I have advised many to drill those holes out bigger to prevent any drainage restrictions.

[Runtoeat]

Hi Roger. Hmmm, how could Canada have such good beer but have bad water?? Good idea to drill out the drain hole. I think a 1/2" hole is the way to go. I'll still check it when I do my prefilight.

[Roger Lee]

Maybe that's why the beer taste good. :lol: :lol:

[floats]

After the fin becoming soft like a piece of cloth, bubbles are now appearing on the tail boom where the tie down provide by FD is attached (the black strap). Has anyone seen something similar on their fiberglass. You need to open the picture in a new tab to see the bubbles on the tail boom above the fin.

[Znurtdog]

Hopefully just the paint??

[Roger Lee]

I'm not sure what this is, but wouldn't surprise me that it is water caused. H2O between the carbon fiber and the gelcoat/paint.

[floats]

After the fin and the tail boom, it is now the vertical stabilizer that is delaminating. The plane has not yet 100 hours and is hangared all winter. As it is on the top of the stabilizer, FD cannot say it is accumulation of water. It is not washing products either as to clean the plane I just wipe the accumulation of humidity early in the morning as all bugs and dust are fully softened by the night humidity. No products required and it leaves the plane sparkling.

[FlyingMonkey]

Wow, this is getting disturbing.

[WmInce]

Not good.

Please keep us posted on the status.