choices, choices

[rhofacker]

Ok folks, I'd really like to hear your comments. I'm considering two aircraft for my homebuilt project: The Cozy and the Dyke Delta. Both are completely plans built, both are 4 palce, both have (I think) roughly the same useful load, and both have a high "cool" factor

 

I've built one rag and tube aircraft. They are easy to build and go together quickly. I've also discovered that I'm alergic to some of the old popular composit materials (a concern ). The Cozy wins hands down in the speed department. I think the Dyke Delta has more cockpit space. I would certainly mod the Dyke Delta for side-by-side seating for the pilot and copilot (I've already worked the CG numbers, etc.).

 

What "pros" and "cons" can y'all think of?

 

What were the considerations when you made your choice? What was most important to you?

[Jon Matcho]

Ron, you know my vote. I'll leave you to decide the quantitative factors, but I must say that the Cozy is 38 units more cool than the Dyke Delta in my book.

 

Popularity

Next to RVs and Lancairs, I believe the Rutan canard design to be the most popular and widely supported out there. This link at the Airventure site had this to say about the 2003 attendance:

 

 

It should be no surprise that the omnipresent Van’s RV series, from the single-place RV-3 to the prototype four-place RV-10, led the list, accounting for 36 percent of the homebuilts in attendance! Second were the designs of Burt Rutan—from a single VariViggen to to 57 Long-EZs kneeling in the Oshkosh grass.

Builder Support & Community

With the Cozy, you have several support sources competing for your attention. For the Dyke Delta, you might have trouble finding another person at or near the same stage you'll be at. Even if Aircraft Spruce shut down, you'd be able to finish the plane.

 

Time-tested Metrics

With the Cozy, you have an excellent reference from many existing builders and flyers for how long things take, what options exist, and what they would do differently (if anything).

 

Composite Material Allergy

Regardless of the plane you decide, you do want to be careful as both use fiberglass. I do think that the community, as a whole, has become much wiser in the ways of preventative measures. I have 4 different types of gloves and 2 different respirators. You can put yourself in a bubble if need be -- one of those white Tyvek suits. If you can't handle epoxy, foam, and fiberglass, consider an RV-10 (but I hope you'll manage).

 

Individuality

There are so many proven and half-baked ideas out there that you can turn into your own -- the Hofacker Cozy Mk IV. Some of these designs have virtually become unofficial "stock" options.

 

 

What was most important to you?

I recall these factors at the time:

• Nat Puffer is alive and well (now 'Aircraft Spruce is a solid business')
• ACS&S AND WICKs are providing "kits"
• A fairly robust aftermarket exists
• www.cozybuilders.org
• the COZY e-mail list and the Canard Zone Forums (this forum)
• Builder Web sites
• Other forums and e-mail lists

Now that I'm building, I'd move the items relating to builder sites and community lists/forums higher up in importance.

 

Hope this helps. Here's another thread on this forum discussing the RV-10 vs. the Cozy Mk IV that might also help.

[rhofacker]

Thanks Jon,

 

You make very good points.

 

The Cozy builder community is a major, major plus!

Indeed, in the final analysis it may be SAF (Spouce Approval Factor) , the builder community, and the cruise performance that become the deciding factors. In that order.

 

I was leaning toward the Cozy anyway. And as you said in another thread, "Which plane do you LOVE, 50,000 rivets, 400 yards of cloth. Hours is Hours." I my case it would be many feet of steel tube, or yards of cloth...

I LOVE them both

 

Both airplanes have a high SAF. Although my wife is not too keen on the Cozy "as designed" ingress/egress. But, I'm willing to take the time and get the engineering assistance to put doors on in place of climbing over the canopy rail. So that is a resolvable issue. We'd still have to deal with the "climb over the canopy rail" for the back seaters in the Cozy.

 

My biggest "worry factor" had been (is?): allergies to the materials - probably less of an issue with more modern materials and the recognition of the problem. With the awareness comes the proper preventative actions. To make a long story short: on a previous airplane project I developed a serious reaction to Imron paint even though I was wearing a positive pressure paint hood, I got enough paint on my skin to make me really sick for a loooonnng time. I'd sure hate to get part way through a project and have to give it up because of allergies.

 

Durability is long since proven by the numbers of planes around

 

Inspectability - still concerns me a little bit: there's lots of structure I can't see or touch...). Again probably not a real issue (see durability above ) and I'm gaining confidence in the inspection techniques as I learn more about them. Oh, by the way, this is a subject I'd like to pursue in more detail. Maybe on another thread.

 

Rag and tube is familiar and easy. I guess I should go ahead and do the introductory/educational part of the plans (I have E-racer plans right now but will get Cozy plans in the near future...) and see how it works out Do you think the "classes/demonstrations" are a good thing to do? or is this something you can easily teach yourself? Time and money well spent?

[Jon Matcho]

And as you said in another thread, "Which plane do you LOVE, 50,000 rivets, 400 yards of cloth. Hours is Hours."

It was Dust that said that.

 

 

Although my wife is not too keen on the Cozy "as designed" ingress/egress. But, I'm willing to take the time and get the engineering assistance to put doors on in place of climbing over the canopy rail.

So let's get to designing our doors. This can be done, in exchange for some weight. In the meantime, highlight all the safety features to further increase your SAF metric. You could explain that the cabin was modeled after the same technology used in many of the Niagra Fall's barrel successes.

 

 

We'd still have to deal with the "climb over the canopy rail" for the back seaters in the Cozy.

Nah, throw them in the back like ballast. I personally don't think back seat access should be a major concern.

 

 

...I developed a serious reaction to Imron paint even though I was wearing a positive pressure paint hood, I got enough paint on my skin to make me really sick for a loooonnng time.

If that's your entire history on the subject, chances are you'll be fine -- just take all the possible precautions -- gloves, no exposed skin, and good masks.

 

 

Durability is long since proven by the numbers of planes around

Inspectability - still concerns me a little bit: there's lots of structure I can't see or touch...).

The data shows these planes last very long. This would be a good question to ask on the C-A list. No/little wood is good -- no rot, as well as little metal to oxidize. The structure is actually the last thing I'm worried about failing.

 

 

Do you think the "classes/demonstrations" are a good thing to do? or is this something you can easily teach yourself? Time and money well spent?

If they're nearby and convenient, then "why not?" I chose to visit builder projects at a few citys I happened to be traveling to, which is great even if you just look around. Call ahead and you can offer to help someone already underway -- I would have easily taken an epoxy mixer. Finally, order the practice kit from Wicks or ACS&S and you'll see firsthand how EZ it really is. Either visits, classes, the practice kit, or Chapter 3 in the plans is all you really need to get going. "Just do it."

[CBarber]

I did take the composite class that SprotAir/EAA offered when they made their yearly trek to Dallas two years ago. I found it worth my time. It gave me a sense of comfort to have had some hands on experience. The class was the only real composite work I had when I started my Velocity project. Now that I am two years into the project (well as of June 9) I am very comfortable with working with glass and epoxy.

 

I too am a fan of project visits and I have had several folks visit my hanger/garage, but I did appreciate the more formal class enviroment the the SprotAir class allowed. Also, I liked the fact that I REALLY was not bothering another builders progress, nor learning another builders bad habits <g>. That is true even though I enjoy it when folks visit me (and picking up my bad habits) and, as those who have come by can attest, I LOVE to talk about the project <g>. I agree the class may not bee absolutely needed, but it did move me past the base fear factor of starting a project untill I became comfortable with the process. FWIW.

 

All the best,

 

Chris

[Spodman]

I would agree the Dyke Delta is a striking looking machine, but I wonder if its a terribly practical aircraft? I've read a scathing flight report yonks ago in a US magazine, the handling was ok but the climb performance dangerously bad. This may have been fixed with the O-360 people that come up with a google have fitted. Can't find any sites that brag about the performance.

 

Without the skin. This shows rear seat room possibly even worse than the Cozy! Though the seatbacks are straighter so less room needed maybe. The structure seems to have a similar sill height to the Cozy and no sign of doors in it, but I bet you can't fit an electric noselift to the Delta. This option is an authorised change to the plans and makes entry MUCH more practical to the plastic beast.

 

Phil bought this and has 39hrs on it. Looks lovely, but with 100hr up It's for sale with this to say "...the rear spar of the center section has rust that will require it to be replaced. Getting access to it will be labor intensive but possible." Crivens! Did he park it in a rock-pool? Cozy built of plastic, don't rust.... erm. Except for the crush plates???

 

An accident report on a stalled (modified) Delta says about the standard design: "The designer of the original prototype described a fully developed stall in this airplane as a mushing characteristic, resulting in a high sink rate and temporary loss of control." (My emphasis) A nastier concept than a fully controlled nod, nod, nod you get with a canard.

 

I still can't find anything about the performance so nobody's bragging, but the landing speed looks more reasonable than the Cozy, reports that make me worry say if you get off the runway you:

 

a) Still may not get out of ground effect

b) Still might skip along the runway for a bit!

 

I think Buck Rogers would have had a hard time picking between the two

[Marc Zeitlin]

I still can't find anything about the performance so nobody's bragging....

Ernest Christley, who's building a DD, has specs on his web page at:

 

http://www.ernest.isa-geek.org/intro.html

[Jon Matcho]

Additional specs can be found at the Dyke Builders Network, which are slightly more conservative. I think this is where the community factor comes into play. With the Cozy, you have so many more information sources to choose from that it's much easier to gain a level of confidence on such things.

 

Personally I don't get the same tingle-up-my-spine feeling with this plane as I do when I see a canard shape in the air, on the ground, on the Web, in print, or in my dreams.

 

Still, a very interesting feature of the Delta is that the wings can be stowed on top of itself and trailored home by car -- without a trailer.

 

 

I think Buck Rogers would have had a hard time picking between the two

That might be true, but we all know that Duck Dodgers, Spaceman Spiff, and Marvin the Martian would all pick the Cozy.

[Pilot E]

How much time do you want to spend?

 

They might take the same time, to plans, but you are already modifying the DD in a major way. That means lots of mods to the underlying tubing, no? And perhaps the controls... etc etc.

 

Sure its an experimental - so go ahead! But if SWMBO won't sit in the back, I'd look for a different design. Get in the air.

 

So I write before asking a major mod question!

[rhofacker]

SWMBO

SWMBO???

[rhofacker]

Just curious This may be a little off the original specific question but as I read other forum posts about choices I wonder if the more general question might be posed to any builder is: What were your considerations for deciding what project to build, and what was the relative priorty of those considerations?

 

Was the construction material a major concern? (you can learn anything that can be learned)

 

Was cruise performance a major concern? (there are several high performance chioces these days)

 

Was number of seats a major concern? (relatively few with 4, many with 2, many with 1)

 

Or was this (what ever your choice) just the "coolest" airplane you ever saw? (and thats all that really mattered - all the rest was only justification)

 

What other things did you consider?

 

The building has got to be as important as the flying (At least it is to me... ). After all you can get a 50 year old flying spam can for the about the same $$$ that carries 4 people at 150 Kts safely and comfortably and be flying instead of building. I know some people make "snap decisions" and never complete the project or just sell it when they're done. Others ponder for ever and never even get started. The hunt for the "right" project is fun too. But, I do plan to get building. We've got "the hunt", "the build", and the flying". There is lots and lots of interesting stuff here about building and flying. But what about the hunt? Come on folks, tell the truth now. Lets us know how you chose.

[CBarber]

First, SWMBO = "She who MUST be obeyed". (Jana really hates this expression.....so, I obey her and don't use it......when she is around)

 

As to why I chose my project......Because the Velocity is the KEWLEST bird I have seen and I fell in love with it way back when I first saw it advertised....I think in college or grad school. Oh, and (time to justify), I can use it on business to go visit clients around the GSOT AND write it off, AND it has four seats (so, seating for two, plus pups....not kids, real dogs, and other stuff) AND it is pretty dang fast AND I can work on it myself AND the pride of building it myself AND being able to be smug around Bonaza owner/pilots ......oh, did I mention it is kewl looking.

 

All the best,

 

Chris