The International Cessna 170 Association

Carbon fiber is great stuff and I have flown my share of Carbon Cubs delivering them from the factory to their new owners. They are built beautifully and fly very nice.

But, my initial concern with carbon fiber is still a major concern to me. Nobody knows how long exposed, non-UV protected carbon fiber will last exposed to sunlight and the weather. Fiberglass boats were cool too when they first came out but if not painted and left out in the sun, will start to disintegrate in a few years. Will carbon fiber do the same thing? Nobody I have asked knows the answer but I bet it will. There is a lot of exposed carbon fiber out there.

Now consider an aluminum C-170. You can leave a bare aluminum 170 out in the sun for 65 years and as long as it is kept clean, it might tarnish some but it is still in one piece and airworthy. I don't think 65 year old carbon fiber will do that. I'm with Arash, give me a stock aluminum 170.

I'm with you on that Richard. The carbon fiber fabric itself should be OK. It's the bonding agent/resin that you don't know how long will last. I can't imagine that it will last anywhere as long as aluminum.

I think the carbon fiber reinforced plastic could last longer than aluminum structure. The weakness will be untreated impact damage shortening the life of CFRP cub components but both construction types suffer when damage is not attended to.
I'd love to own a CC but presently, I 'm more than a few dollars short. I'd love to see a carbon 170, would jump to buy one, although likely I couldn't afford that either. If a new carbon 170 was made, maybe it would help sustain GA for future generations ?
Safety first , always, donning the suit.

Was a 100 year operational life span a design consideration when Cessna decided to use alclad aluminum? Or was it the cost effective solution of the time?

Fiberglass boats from the 70's are still in service today if maintained and they are readily repairable.

I'm sure the same arguments were made over an all aluminum Cessna when they came out.
Are you kidding? All aluminum skin? You have no way to inspect anything! With cotton you get to inspect the whole airframe every five years! Those all aluminum airplanes are a corrosion death trap waiting to rot out of the sky in ten years.

Carbon fiber is an incredible material that has a lifespan that will exceed all of us on this forum.

But, it's not 1940's technology so it shouldn't be used on REAL airplanes.

hilltop170 wrote:...

Now consider an aluminum C-170. You can leave a bare aluminum 170 out in the sun for 65 years and as long as it is kept clean, it might tarnish some but it is still in one piece and airworthy. I don't think 65 year old carbon fiber will do that. I'm with Arash, give me a stock aluminum 170.

Richard, I see your point but... no one leaves an airplane out in the sun for the purpose of keeping it clean. They fly the darn things. And that is why the aluminum cowls CRACK. Vibration and impact hurts everything. I suspect the aluminum is lighter than either carbon or fiberglass.

I sure wish someone would 3-D print up a set of nose-bowls tho' (if Bruce hasn't already.)

How did Cessna form the nosebowls?

Big stamping press? Hydroform? elves with hammers?
The rest of the cowl looks pretty straightforward, though there's some compound curve to the upper surface.

It's my nose bowl that suffers the worst after 67 years in service, sitting out on the shaky end of the plane. Multiple patches. Elongated holes. It really is the weak point in cessnas mid 50's metalwork. They just don't last. No cracked patches yet.

Aluminum would be ideal, but a carbon fiber nose bowl replacement would suit me fine. As long as it looked the same.

Done right, no one would notice.

After about 130 hrs my fiberglass nose cowl started to crack. While a bird strike started it off this cowl the way it was wasn't going to last . I ended up soaking some polypropylene rope in resin and reinforcing the inlet holes with that and then patching up the cracking . So after about 380 hrs I will have to reinforce it again . I can't see carbon fiber inlet working well. However as I have a heap of Kevlar now the repairs will be done in that . It's also the screw attachment holes give trouble also .

I think you guys underestimate a carbon fiber layup. You can't compare it to fiberglass.

bagarre wrote:I think you guys underestimate a carbon fiber layup. You can't compare it to fiberglass.

Preach.

It drives me nuts to hear it called carbon reinforced plastic. Anyone that wants an idea of what the stuff can do needs to Google Rob Holland. No cracks in his airplane and I've seen it torn down every off season for inspection. He broke a motor mount last year and didn't damage any of the carbon parts.

I've been toying with the idea of replacing all the interior trim pieces with carbon reproductions, as well as replacing the floating panel with a carbon plate, if a DER approved. I appreciate all 170s, though it makes me sad to see some of the cobbled-together crap that makes it into them. I consider myself an originality nut, and my mind's eye picture of the perfect 170 is the shot in the documentation library of Jim Beyer's airplane, but I see many places where carbon can improve and enhance these airframes. 56D is a huge part of me and has been my entire life, literally. I want to do whatever I can to ensure she outlives me. If carbon parts are the answer, I dig it.

How well does carbon fiber handle open flame? That might be the biggest issue of using it in the cabin or around the engine.

Ultimately the word "composites" has to come into the conversation.

Yes carbon fiber is in the mix for strength but the technology is still advancing.

See Scaled composites, Burt Rutan , Paul Allen.

Good to see that some C170 fans are thinking carefully about potential applied benefits of technology.

Forever thankful for the invention of Alclad.

This thread is slowly reminding me why I don't post here as often.

It should be re-named the Cessna 170 Purist poo poo if it ain't original Association.

I just spoke to someone today that says there is a guy who installed an TCM IO-360 in his 170B. He lives in California and works for Skunkworks. Story goes he is actively and very close to getting an STC for this discussion of a cowl. I have never heard of the guy before so I cannot verify this yet. Trying to remeber the name. It was mentioned once in the conversation. I will try to get more info. D

Aryana wrote:If your goal is to run all the folks off from here that like original 170's, you should ask yourself why it bothers you so much?

It's the other way around. The folks on this site run off anyone that do anything other than keep them original.

Aryana wrote:

bagarre wrote:This thread is slowly reminding me why I don't post here as often.

It should be re-named the Cessna 170 Purist poo poo if it ain't original Association.

So dramatic. So let me get this straight, I'm supposed to never express my desire to have my 170 appear like it did when I was 10 years old. Got it.

Good luck doubling the value of your 170 with a carbon fiber cowl.

I don't want my airplane to look like it did when I was ten years old.

Mostly because it was in pieces.