rhofacker

Does anyone know if there is a Cozy or Long-eze data available for X-plane? I thought I saw one someplace but now I can't locate it.

Are the wings and canard for the E-racer the same (area, airfoil, sweep, twist,etc.) as the Long EZE?

I was just re-reading the CAFE report on the Cozy. He talks about a 3000 ft landing roll. I assume without any braking. What landing distances do you see in common operations? What field lengths are you comfortable flying into and out of? and at what field elevations?

Ron,

 

Congrats on ordering your plans. I am tickled pink. I hope you will invite me over to check it out once you get started. You are welcome to come over and check out my project anytime....even if it is a Velo .

 

You know, we all feel sorry for ya having to suffer in your Bonaza with that throw over yoke . Remember, the Velo has a yoke option....which is what I have, so more room in the center and you can fly left handed from the left seat).

 

Also, FYI, EAA Chapter 12 finally voted to move its monthly meeting to Ellington. We meet the second Wednesday of the month at 7:30 pm at Southwest Services FBO second floor conferance room. However, this month we are suppossed to meet at the Collins Foundation for a tour of the various planes they have (B-25 etc). I want to personaly invite you to come on out (fly in from Polly Ranch would be REALLY kewl). I was the PITA instigator of the move from Houston Southwest to Ellington, so every new member will help reduce the possibility of egg on my face <g>. Now that you are a builder it should be a nice fit.

 

Ellington has a number of builders. I met a new Chapter 12 member yesterday who called me and invited me over to check out his new "ViperJet" kit. Wow! 450 kts and it is a kit. He may even offer part of his new "big" hanger for EAA use (of course, you have a hanger behind your house, but good for the chapter anyway)

 

All the best,

 

Chris

Way cool! We'll try to make it to the chapter meetings. I'm very intrested in your Velocity. As I said it has a LOT going for it and a lot of things I may copy (like the door.. ). I'm really intrested in your Wankle rotary engine. It's a long way done the road but I'm really thinking of going that way myself unless something better pops up in the next few years.

...actually the throw over yoke has some very real benifits: it gives you a lot more room for the navigator. Which ever seat he/she might be in... :

and a lot better visibility of the panel space often obscured by the second yoke.

I wonder if I could get a Viper in and out of Polly Ranch if I won the lottery...

Well it's official: I'got plans serial number 1299

The debate on Cozy Vs Velocity will no doubt go on for ever

There have been a number if threads about it on this forum and in the e-mails flying around.

To me the bottom line is: Velocity: larger, roomier (4 real people), easier ingress/egress and kit built (larger initial outlay of $$$). If you ever get the chance to try out the Velocity gullwing doors, you'll be spoiled for life. It really is a major comfort factor. No climbing under or crawling over anything. It beats the snot out of anything else out there: commercial built or homebuilt for a "cross country" type airplane.

Cozy: smaller (2+2) seating...(really a nice 2 place with lots of baggage room)

possibly faster, possibly "better" ("better" being a very relative term: quicker? lighter?) handling. The center stick is a non issue to me. I've flown several older homebuilts with center sticks - no problem. I also fly a '51 Bonanza with the "throw over yoke - no problem, no sweat.

I chose Cozy (plans are on order) because it is plans built and therefore I can lay out the money in smaller chunks (there are other ways to deal with the cash flow issues: a loan for example while interest rates are low...) and I can deal with the other preferential short comings (mine will have doors of some sort - no climbing over the canopy rail for me even if it costs me payload. Even if it's not a "Cozy" any more). After lots of discussions with the wife, lots of spread sheets trying to prioritize and rate features, lots of soul searching the "plans built" was the real deciding factor.

If you want a true 4 place or if you don't want to "deal" with converting "plans" into an airplane go with the Velocity. If you want to make any preferential changes (like a door on the cozy) then plans built is the only way to go...

Has any body compiled and/or posted the cost of a complete rotary installation? All the mods, the PSRU, the ignition changes, overhaul costs on used engine if that's the starting point?

If you've gotten as far as putting a rotary in your project, what did it cost? What did you buy and what did you build?

I've tried to add up the costs and it looks like the initial installation is not cheaper than a certified engine like the XP-360 or the Franklin. Cost savings would be at overhaul time...

I've got a composit learner's kit on order from Aircraft Spruce. I was actually thinking about making two of the desrtuctive test samples Burt tells how to make in his book that I got with my veri eze plans. Make one with and one without the peel ply/plastic routine. weigh them both and break them both. I'd sure like to be confident in a process used throughout the project

weighing the peel ply before and after should tell me how much resin I pulled off...

"...would not be putting loads on the centersection spar..." erm yeah, that's what I said...

 

More than anything the idea of TWO independant retraction systems gives me the horrors. Both down for landing, both up for flying, one up one down for parking. The odds against reliably picking the right arrangement seem insuperable.

That reminds me of a true story about a wealthy Doc. at the little airport where I learned to fly. This gentleman went out and bought a Lake anphibian and proceeded to land gear up on the runway at my little town. He had the airplane repaired and then landed gear down in the water at the local sea plane port. Contender for a Darwin award? Well, it didn't kill him but still, how would like to have this guy operate on you?

"check gear down and locked" should be a prominant landing check list item

IMHO, retracts are NOT worth the effort. I admit, they look "cool" . But the speed benefit, 15 - 20 mph more.... Not worth it. I am assuming that there is a weight penalty as well. Plus, you carry less fuel right.

+20 kts is a good thing and truth be told in the final analysis the coolness factor is going to play a BIG role. The rest of it is rationalization. There is a long list of issues: time to build, weight, $$$, etc., etc. But when all is said and done are you gonna say to yourself "wish I'd spent the extra time and $$$ to go that last little step"? Not everybody is going to want to put the extra time and money into it. (any problem can be solved with enough time and money )

I suspect you don't have to sacrifice total fuel volume. just put it somwhere else. The "Ifninity" web page addresses this. but let's assume you're willing to pay the price in terms of $$$, and usefull load. I'm trying to think through the installation precess, and see what all gets hit by the "domino" effect. You know: you change one little thing and a dozen others need to be changed also. Some of them unexpected. For example, I had been thinking that the E-Racer style gear would be simpler untill it was pointed out about the unknown (at this point) impact to the design/installation of the rear seat (and that one should have been obvious ). The great benifit of talking about it on a forum like this one is all the different people looking and thinking about it. and, yes, even throwing rocks at the idea.

I have plans for a retractable gear from long, long ago for a CA-65. It's totally mechanical (or electro-mechanical) and built with "off the shelf" gears, springs and 4130 tube. So, I'm still mulling that one over too.

...uuhhmm... I think the E-racer style would not be putting loads on the centersection spar since it's hard points are in the fuselage...

But, you're certainly right about unknown changes to the rear seat back.

The E-racer retract mechanism occupies a space from the firewall to roughly14" (guessing from looking at sketches/pictures of the E-Racer) forward. Some of that is also occupied by the wing centersection spar. What's the distance between the firewall and the Cozy seat back at the top of the center section spar and the distance at the bottom of the seat back?

With the understanding the the Cozy is a cross country machine not an aerobatic one. what are your opinions about the flying qualities in general and roll rate and pitch/roll control harmony? Do you find the roll rate satisfactory (marginal, excellent, perfect)? and do roll stick forces match pitch stick forces? What GA airplanes would you compare it to? This was discussed in the CAFE report but I don't have it handy and I've heard some criticism of the roll rate/roll authority at low (landing) airspeeds. I'd like to hear opinions from folks with longer actual experience in the plane. How long are you comfortable letting the plane fly "hands-off" in moderate turbulence (while folding maps, getting a drink of water, looking for the pen you just dropped, etc., etc.)?

I've used a similar technique on "stich-and-glue" boats. Basically you cut a series of pannels from plywood, stich them together along the edges with safety wire, flox the inside corner and put fiberglass tape over that. Let cure. Remove all the wires and cover the out side of the boat with fiberglass cloth and epoxy. Sanding as needed, of course . Now, the peelply and plastic works very, very well over the flat and/or simple curves of plywood and I would expect it to work as well on flat (like bulkheads), or simple curves (like the wing) surfaces. But how do you do it on compound curves or concave surfaces? the plastic wrinkles around the compound curves and in the concave corners

OK, Let's assume for a moment that you have decided to commit to retractable main gear. There appear to be two basic systems: 1) the "Infinity" style with the gear attached to the main wing spar and swing inwards to the fuselage and 2) the "E-Racer" style with the gear mounted in the fuselage and swing outward into the wing. What are the "pros" and "cons" of each?

Here are a few I thought of:

"Infinity" style frees up volume in the fuselage for a fuel sump to recover and/or add to any fuel volume displaced in the strake by the gearwell. "Infinity" style has potentially <slightly> "cleaner" installation: does not have the "bulge" or "blister" covering the wheel that does quite fit completely into the wing/strake. "Infinity" is more complex - oleo strut vs. composite strut. Possible structural considerations in wing spar. $$$? does anybody know the cost of the E-racer gear? Weight? does anybody know the realtive weights of the two systems? Other considerations or thoughts? Other possible system configurations?

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.

SWMBO

SWMBO???

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?

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?

It does make me appreciate the marvellous support available for the Cozy. The Aircar yahoo group has virtually no traffic and the distributor of the plans is MIA.

The four biggest reasons I'm seriously looking at building a Cozy:1) completely plans built (no vendor to go out of business half way through your project ), 2) great builder support, 3) The excellent performance and, 4) four place (well 2+2 OK?)

So Marc, the Zeit part is easy, but the 'in' with the long 'i' is confusing for me. Is it like 'site' + 'line'? Zeitline?

 

Confused in Jersey.

What I wanna know how to pronounce is "RONCZ"

I'd like to add that the pressure distribution looks like I would have expected as a layman with the exception of the blue high pressure on the very aft protion of the fuselage. I would have expected a low pressure area (red) infront of the prop as air is accellerated into the prop... What am I missing here?

I remember there being a lot of discussion about boat tail drag and poor airflow into the prop on the original Veri Eze. Also, I think, at one time Shril Dickey talked about less than expected performance from his E-Racer early on due to poor airflow into the prop. In his case he trace the problem to the location of the engine exhaust as I recall. Have we done all we can in this area?

Cool

I'll go have a few more cocktails to get some more cocktail napkins for drawing on.

Try to post the sketches here

then put on my flak jacket and watch for "incoming"

I absolutely, utterly, completely, agree Dust. I'm now to the point where I wonder why so few have tried turbocharging.

As for the Oxygen mask, it is not such a simple leap of faith, going hypoxic is very dangerous indeed. A few business jets have experienced un detected de-pressurisations, and simply fly on until they run out of fuel. Who was that golfer? Was it Payne Stewart?

Plus I hear you can get the bends, and severely damage your eyesight up at those pressure levels.

The air might be -40'C, but being very thin cooling can be marginal, but I think the higher TAS may compensate with proper ducting.

 

However the reduction in drag is a major bonus, you sit high above all the terrain and cr@ppy weather and icing, and with a 100 knot tail wind you might see the GPS reading 400 mph.

 

I think if my calculations are correct, 300 mph True requires 200hp continuos at 25,000 feet with an Indicated airspeed of 200 mph in a Cozy MkIV, at standard weight.

 

How about turbo charging, retracts, and O2?

That makes sense. I mean tying drag and L/D into the question of "best" trade-off.

Operationally it wouldn't necessarily be a penelty to have higher drag at Cl max. Just like high drag/high lift flaps on a conventional airplane is not undesirable for the landing configuration. A good L/D in the climb configuration would be a good thing and low drag in cruise would be a good thing. What I don't understand yet is how (or what part of) the aircraft performance envelope would be improved by the GU airfoil...

Low drag at cruise is good - score one for the Roncz airfoil

Better L/D at climb Cl is good - score one more for the Roncz airfoil

Low drag at Cl max is not necessarily good - call it a draw

Higher Cl max may not be good if it is achieved at a higher AOA and cannot be utalized due to other limitations of the design (like main wing stall on a canard configuratiion). Usually a higher Cl max achieved by increased camber also moves the minimum drag AOA up. It does occur to me that this might be desirable if the canard airplane is nose heavy But that's not usually the case in practice. So, I'm gonna call this one "score one more for the Roncz airfoil for the Long eze/Cozy application. Other applications may reach different conclusions

Also, I'm still a little bit dubious (I'm an old flight tester: math models are good, wind tunnels are better, but the proof of the pudding is in flight )about the comparisons at Cl max: Xfoil and other math models do work well at low to moderate angles of attack they do not always agree well with measured performance at high angles of attack. Also, Rutan specifically recommended against retrofitting the Roncz airfoil on the Veri Eze because of it's "higher lift". I'll have to go look for the specific CP news letter... So, the higher Cl max may not be "real" and if it is real it may not be "good" or usable.

And WRT the external trim tab: I'll go look at my Veri Eze plans tonight but I'm certain the original Veri Eze that I saw at Edwards AFB and got a brief ride in way back in the '70s had a small external airfoiled tab on the elevator to reduce the pitch control force

Somewhere on this forum I saw a couple of pictiures of a Long Eze showing pressure (or velocity?) distribution over the surfaces. Red for low pressure regions and blue for high pressure regions. I have a paper copy, but I have lost track of the electronic version. Does anybody know the original source for this? and the simulated conditions? It looks like it might be "high speed" and possibly with out simulated prop thrust. Is there any other information like this available?