Twin EZ

Did you ever get the brake problem fixed? What was the problem?

The full flying canard was just an "IDEA" At no point did I say that I was going to do it. But it would look nice. So....that idea has been officially scrapped.

Still going foward with designing a twin though

yep but but pushing it around the compas rose on the ground (gear down) to compare the real headings with your compass and then fly with the gear up and some steel closer to the magnetic sensor will get you different readings, still confused?

 

I guess that my thought would be to adjust it on the ground (out of true), so that when flying it would be true.

Wildbird,

Went through your pics. Looks like you are doing a great job. Keep up the work and you will be flying in no time.

, I ended up installing it under the frontseat, works good, you only have to compensate with the gear up.

 

Wolf.

Confused??? Isn't that most of the time when flying???

for $550, thats pretty hard to go wrong. Hopefully whoever won the bid, will be diligent and get her flying....one more backwards flyer in the air

I have to agree with everything that you have said. And these are issues that I have been going through. That being said, I could build a fixed canard, keeping the center of lift in the same place, but if indeed we are looking at a decrease in efficiency, for a tappered look, then forget it. The end result needs to work better, not worse.

Im still going foward with the twin idea though:D

full flying is just that, the whole surface will move. I have not run the numbers yet. But I see no reason to have to extend the nose. the sensitivity is controlled by the amount the control surface moves in relation to the stick movment, and the amount of force applied by the anti-servo tab on the trailing edge. This is only a theoretical idea here...nothing concrete.

Back tot he origin of this post:

Attached is a pic of he full flying canard idea. But who knows, maybe its just fancy-full thinking. But then again, that is what this section is about

NOPE. They are engines for aircraft. (not motorcycle, auto, marine, etc)

I think that Bowden started out with a good idea, and I would love to chat with the guy to get some specific details since I was not able to see his plane in person. His engine choice was pretty good, although I plan on using something else (I'm keeping that part a secret forthe time being). But I do agree with keeping the engines in the 80-90 hp range. I feel that his aero-dynamics for the cowlings were terriblly wrong. We cant afford to put to engines in the breeze and use a boxy cowling that he did with what appears to be holes drilled in the top (cooling issues maybe????). It is imperitive that the cowling and ducting shapes be done in such a way so as to reduce the parasitic as much as possible, otherwise forget it. I have no plans on flying a plane with a top speed of130 kts burning 6-7 gph. What would be the point in that?? Also, looking at his pro choice limited his performance. If we look at the amount of pitch the prop needs to get the kind of cruise speeds in a LE, how in the world can 80 hp spin it on take off. I would imagine that either he had relatively fine picthed props or he would never get of the ground. On a singlke engine, there is more horsepower to push a course pitch prop. I think that it will be necessary to run adjustable props to make this work. Unfortunately that does add complexity, but a necessary evil to the design. Bowdens engine placement seems to be pretty good (approx 5' apart). I can not tell the distance from the prop to the trailing edge. If was to close, there are some efficiency losses occuring there as well.

To the best of my knowledge, there are no problems with the existing canard design. (especiall the Ronzc design). My point wasnt to "solve" a problem, but rather to explore other possibilities. On conventional aircraft, you can get away with a small surface area on a stabilator vs convetntional stabilizer/elevator combination. (albiet, the forces are in the opposite direction). If indeed, the same reduction could be possible in the canard confiuration, we could achieve the same required lift, with the appropriate stall characteristics, while reducing the surface area, which in turn could reduce the induced drag. That was my thought anyways.

Twin you may want to look around on this site (or in the CSA newsletters)... I beleive there was a LE that was built with 2 80hp Jabiru engines. The owner decided to convert back to one because of the observation made previously (not enough power to maintain altitude on one engine)...

 

If you were to have red this thread from the beginning, you would have noticed that I have commented on Bowden's LE a couple of times.

That's very hard to believe. I'm not calling you a liar, but 75 a/c from SCRATCH! In one lifetime...? Sorry, but this is pegginig my B.S. meter.

 

Can you prove this statement?

 

I can't even fathom someone building 75 from kits, let alone 75 from scratch...

 

Its not that hard, when that is what you did for a living for 8 years. So, yes I can prove it. Thanks for the attitude, gives me that warm and fuzzy feeling all over.

Make no mistake about it, my goals are to design it so that it will maintain on one engine at 80% power. My calculations show that running at 1300 lbs, it will maintain altitude on one engine, holding the speed at 100 knots. You may be refering to my take-off emergency senario. I wanted to simple point out that a twin is not a placebo. It can not be the savior in every situation. But 99% of the time, it can save your bacon. In the end, the proof will be when it is actually flying. I am confident that a Twin LE can be done, reliably with some amazing performace results.

Sometimes we all take a break, but then one little spark lights a fire inside, and we start cranking away. Keep up the motivation and dont quit:cool:

I wont be doing any work until I am satisfied with the design. And of course there are financials...I was forced to close down my business about 6 months ago..that hurt. But I will definately keep everyone up to date.

Eveyone has an opinion and knows what they are comfortable with. And thats ok. I am not here to "convince" anyone that a twin is better than a single engine aircraft. It is simpy my preference for my next plane. Lets face it, if everyone wanted the same plane, same paint, same engine, same guages, same interior.....BLAH..what would be the point. I am a firm believer in going from the "know" to the "un-known" slowly. Taking baby steps along the way to make it right.

Anybody remember why Lindberg decided on only one engine?

If I remember correctly, he couldnt afford the windshield, I would guess that the second engine reasoning was along the same guidelines.

There is no doubt about it that there will always be a situation where the 2nd engine may not help out. I have gotten that same response several times, "what happnens if one quits on take off"? Well, I ask this, on a single engine LE, ....same question. Gues what? same answer: fly the plane as best you can and hope there aint a tree or house in your way. Ont he other hand, my calculations show that the LE can sustain altitude with 80-85% power on one engine. There are significant variable involved such as weight and how well the engines are cowled. I believe that properly done, the drag can be quite minimal. I think that one of the biggest problems that Mike Bowden had wat the design of the engine cowls. We cant just expect to cover an engine and call that good. A lot of time must go into minimizing the drag around the cowling and engine and maintain proper cooling. Putting all of the technical babble aside,lets face it...It would be SERIUOSLY COOL

I will continue to rifine my ideas, continually trying to fix any possible problems. I welcome any opinions that are given, but I am not easily diswayed. I think that if the drag stays low, the aircraft stays light, than this can work.

BTW, my fuel burn will be a total of 5GPH at cruise... not bad.

Sounds interesting, I've got two questions though:

160 HP total or per engine?

What's the configuration? (Defiant style or other)

Two 80 hp for a total of 160. If someone were foolish enough to put 2 -160 hp engines on, it would be a disaster waiting to happen. Way too heavy, and if one engine went out, there would be FAR TOO much thrust on one side to keep the aircraft in control. If the power were pulled back to prevent spinning, the aircraft would be be so heavy, it wouldnt maintain altitude.

The engine configuration would have both engines in the rear. Not feasable to put one up front, and why ruin the beautiful looks of the LE and the visibility would be compromised.

Yes I have a twin, but that is not what my name is about. I have be working on designing a twin LE. I know that it has been done before (once by Bowden), and I know that there has been a lot of skepticism about that around here, so I have not made any mention of it. Justt for the record, I have built over 75 aircraft from scratch, using everything from Rotax 277 - 912, subarus and 1 turbo charged honda civic engine. I am not an engineer (admitting that there is more that I don't know than I do know), but I have always loved a challenge. I think that a viable twin is possible with the right engines, and keeping the weight DOWN!!! My planned design has a finished weight of about 975# with 160 HP. Why is it that I feel I have just opened myself up for a bunch of bantering???

In the process of designing my "perfect" Long ez, I was considering building a full flying canard (vs fixed with elevator). Has anyone ever tried it? Are there specific reasons not to do it on a canard? On Convention AC, they work great. I had stabilators on both of my planes.

try going to PhotoBucket. open an account. there you can download your pics (and videos). Once there, each pic will get assigned a URL. Paste that URL at the bottom of your text, and that should do it.

I would be interested in seeing your project.

I agree, try to keep the shorter instrument towards the outside and longer ones toward the center