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WileEZ

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About WileEZ

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  1. Contact your local FBO that also works on turboprops and light jets. They should be able to at least point you in the right direction if not actually order the engine for you.
  2. Doing a quick Google search, the cheapest I found was just for the tool and no accessories at $209. Most are from over $400 to $800, depending on the model and included accessories. Cutting blades are $60 for a 3 pack. As far as I can tell, there is no "single speed" Fein MultiMaster. There may have been at one time, but Google doesn't show one. Boy, what a racket, make a $40 tool and sell it for $400! Likewise, make a cheap stamped and hardened blade that cost 50 cents to make and sell three for $60. I wonder why Harbor Freight doesn't have a tool like this already? The patent on this expired some 20 years ago.
  3. Reading your post, for some reason I had this mental image of a window in the seat bottom and flashing the tower as one fly by... I need to wash my brain out with soap now...
  4. I'll attempt to answer some of the questions with some reasonably educated answers. Keep in mind that I might be wrong, but the answers is what I understand the issues are. 1. The S.American Cozy with the two engines, why didn't they tie both engines to a single prop. My first guess would be the torsional vibration issues between the two engines. IIRC, they used drive belt and it's very difficult to get both engines to synchronize exactly. The builders also turned one of the engine around so it was much easier to do the contra rotation thing. Keep in mind that they had limited resources and made do with what they could get in Venezuela (where I think they build the plane.) 2. Is contra rotating inline more efficient than say counter rotating, but one on each side of centerline? Yaw issues because one prop craps out not withstanding. Yes, because the rear propeller "straighten out" the airflow from the first propeller, thus improving the thrust. 3. If you need to gear down because of an auto conversion anyway, would it be more efficient to build a contra box with two smaller contra props? This could give a fluff factor for high nose landing/takeoffs. No. The smaller propellers would actually be less effective. The main reason for the contra propellers in the first place has to do with engine power. Engines (both piston and turbine) reached a point where they delivered more power than the propeller could absorb and there's a point where you cannot add any more blades to a propeller, so some genus came up with the "contra propellers" as a way to make use of all that excess power. The engines we use in the canards are not that powerful and all the available power is used by the single propeller. There's not much left to operate the "second propeller". There is also the issue of "blade interference", the pulses from the blades swinging by each others could set up some serious and destructive vibrations. That is why almost all (if not ALL) the contra-rotating propellers have at least five or more blades per propeller to spread out the pulses better. Contra-rotating propellers is also LOUD! Much louder than the "equivalent" single propeller. I've seen helicopter designed with contra rotors. Not my area of expertise, but If I had to guess, I'll say it's easier and probably cheaper to use a single rotor and a tail fan, which is why we don't see too many contra-rotating helicopters. Except for the complexity of the system I can't find the efficiency issues on the net. NASA is your friend here, they have reports and research papers on this issue. Edit: Let me clarify that I can find lots of info on boat props, but air is few and far between. Tho from what I've found, could be a good way to go, for some. Sure, if you have an humongous engine! Or, do like the Venezuela guys and use two engines.
  5. Tomwang, that looks really nice! I see you have one of the most important tools, a "moaning chair!" Keep us posted on your progress.
  6. Great trip report! Keep them coming!
  7. If you know digital electronics you can replace the switches yourself. Do a google search for "BCD switch" and ignore the "business directories". A little hacking and you're done. It doesn't have to be "push button", "thumbwheel" versions works just as well. Drawback is you have to know the encoding pattern (code table) for your particular switches and make sure the replacement match the output pattern. It's easy enough to make up your own "code table" once you remove the switches and find a replacement that match the same coding. This link gives an example of a "BCD code table": http://www.elexp.com/t_bcd.htm. Of course the transponder would no longer be "certified", but if your airplane is an experimental and the transponder output on the correct frequencies (have it tested properly to make sure), I think you may be okay. (Not sure, so check on the "legalities".) Not sure what else I can say, except that if this was mine, I would just replace the "push button" switches with a homebrew electronic display (LED), some logic gates and momentary contact switches.
  8. Is this the guy that's flying a Cozy and is in the process of building a Long-EZ? What did you do to that guy? What if the Wright brothers were "realistic", or Burt was "realistic", or Nate was "realistic". What if they listened to the people that told them not to "waste their time"? Would we even be here? I know you dreamed, and you're building. You did something with your dreams! I've seen the inflatable deicing boots close up, the only thing I could think of was, "it looks a lot like inner tubes stuck in place". "Sophisticated", oh please, a compressor is a compressor when all is said and done. Some air valves and a microcontroller along with a small tank is pretty much it. Sure some custom molding may be needed, but how hard is that? We all (most of us anyway) know how to build custom parts out of fiberglass and foam. No new wing design needed, just some careful thinking. But my interest is not in that direction. (At this point anyway.) Beside, I said "probably"! C'mon, you're better than that! Join the party!
  9. Okay I can discuss the details now. I discovered that my "idea" is already being used as a deicer on the MD80. http://www.azom.com/details.asp?ArticleID=1624 In my case, this started when I bought a new electric blanket, and noticed how much faster it heated up than my old worn out electric blanket. On inspection, I noted that the new blanket used much lower voltage (24 volts) than my old blanket. A quick search reveled that the blanket used carbon fiber heating elements instead of the nickle chrome (I think) wires my old blanket used. I noticed that even when I'm sitting outside in my balcony in cold weather (upper 20 degrees f, ~-3 degrees c), the blanket apparently did not have any trouble keeping me warm. In fact, I had to keep turning down the control to keep from "cooking"! According to Wikipedia (http://en.wikipedia.org/wiki/Electric_blanket) "Modern electric blankets have carbon fibre wires that are barely noticeable and produce heat on the far infra-red part of the spectrum, penetrating through other clothes and making a better use of every watt." Implementation of this would be simply run thin carbon fiber strands or perhaps very light woven carbon fiber tapes, perhaps in "zones" in the flying surfaces, between the foam and the top fiberglass skins. along with cheap sensors to monitor the temperatures. A cheap microcontroller can be used to monitor and control the heating elements, using PWM to deliver the currents. Since running the carbon fibers strands is easy, one can also heat up winglets and other critical areas. The power can come from a dedicated, modified cheap alternator of sufficient rating, coupled to the engine via an electric clutch. An advantage of carbon fiber tape (1" to 3" wide) over single roving is that a break in a single strand would not render the zone inoperative. A positive aspect of this system is that it would not get hot enough to cause problems to the foam and fiberglass, yet deliver enough heat to maintain a desired minimum surface temperature when flying in minus 40 degree air. A way to insure this would be to limit the maximum current to the zone. What need to be researched is optimum layout, minimum temperature needed to prevent ice formation, just how much current is needed to run this and if it's even practical to begin with. Also need to determine if normal carbon fiber roving will do the job, or if a special formulated carbon fiber is needed. An idea regarding propeller deicing. Instead of using a brush arrangement to deliver current to the propeller deicer, use a "motorcycle" type alternator, with the coils mounted in the hub and the magnets attached to the non-rotating part. There's some issues with this concept, I'll admit. The brush method would probably be better as there appears to be the same level of complicity involved. Regarding ice flinging into the propeller, I think it may be best to prevent ice buildup past the "trace" stage than to try to get rid of the ice after it accumulate. To address the concern of ice melt running aft and freezing again. Part of this can be addressed by heating the entire wing, but my reading seems to indicate that the ice melt would sublime into gas rather than remain in liquid form. Most in-flight, non-liquid, deicing system seems to focus on the leading edges and the airfoil "hump" rather than on the entire wing as a whole. But I'm still reading and researching this. It appears the main concern about ice build up is not just on the leading edges, but also on the area just behind the "hump" of the wing (maximum thickness) where ice build up destroy the airflow and reduce lift available. I wonder if a reflective material can be placed under the heaters without causing delamination issues. More research needed. Still need the ideal minimum temperature.
  10. Actually, I did! Most of them apparently use the exhaust or bleed-off from the engine/turbine to provide the heat. Unfortunately, nothing about the freezing points, only about the working temperatures. One interesting system used the coolant from a liquid cooled engine to heat the leading edges, it's actually part of the "radiator" setup. (IICR, I read this in one of the innumerable NASA reports.) I don't know if this was ever used outside of test planes. I haven't found any that used electric heat so far. Technical information other than NASA is kinda hard to find. Still looking. NASA is full of interesting and useful reports! It's real easy to get sidetracked!
  11. Sorry, but when I'm in a technical frame of mind, I tend to take things literally. Buddhism at those times tend to be the furthest thing from my mind. Instead of thinking in Buddhism terms, I'm thinking that's a pretty useless and pointless answer. I asked a technical question, and expect a technical answer. I'm not asking a "Buddha question", although it can be said I'm looking for enlightenment, I prefer it in the form of a direct and useful answer. If someone ask me "what is the sound of one hand clapping", I'll reply "clap" "clap" "clap". That's the sound of my hand clapping against my leg. Else it's just a hand waving in the air and doesn't meet the definition of clapping. That's how my mind work when I'm in a technical frame. BTW, thanks for the link, it's an interesting article.
  12. Heat's not the only way, it's just where this one particular train of thought is taking me. As to inflatable boots, you probably can do the same thing on the cheap by using bicycle or motorcycle inner tubes and cut until you end up with a long flat piece. Glue or fasten appropriately and use a 12 volts inflator type compressor to inflate to however many pounds needed to break the ice and deflate. Those inner tubes hold up well to freezing conditions, although UV damage will be an issue to address. Likewise, liquid deicing, take copper or aluminum tubes to a laser place. Have them "drill" a series of really small holes. Embed at or just above leading edges. Pump warmed glycol solution... Keeping them holes clean and clear is gonna be a bugger though. Yes I know the prop is still behind me, one thing at a time...
  13. No not heat tapes, not enough heat transfer. Beside, this apparently has been done and was proven unsuitable (using heat tapes). Yes separate electrical system, dedicated just to the deice system, alternator coupled to the engine via an electric clutch and a very small 12 volts battery. Aluminum strips apparently is not such a great idea, yes heats up faster and and more evenly, but it also cools off faster in free air, thus requiring quite a bit more power. Yes this idea is along the same lines as the heat tape idea, but a bit different. Need to research, build and test. NASA reports, while useful and informative, still did not give the critical temperature point(s) needed to prevent/melt ice while in flight. I may have missed a report or two as there's a lot of research that NASA has done on this subject and I haven't read them all yet. I'm still reading and searching for more reports (not only NASA, but whatever I can find via web search.) I've already accounted for composite integrity and part of the planned testing will be for just this issue. I'm still mulling this over and thinking this through. Just need to find the minimum temperature point and move on from there. This whole thing may prove to be unworkable, then again, it may not. I'm willing to build some test panels/foils and test and document the concept if the paper design and calculations works out. I do plan to share the information whether it works or not. Even if this doesn't pan out, the information gathered hopefully would be useful enough that an entirely different, cheap and safe deice system could be worked out. I know that many airframe manufacturers have done this same thing, but they, for some reasons, are reluctance to share with "outsiders". Thank you for your useful and relevant post.
  14. Yes what? I have been reviewing what was done in the past regarding deicing. So far no answer to the question: What is the minimum temperature needed to prevent/get rid of ice buildup? I'm aware of the surface area issue. I just need to know the minimum temperature required. I know it's somewhere above the freezing point and I'll rather not have to figure this out the hard, long, expensive way if someone have that answer or can point me to the appropriate resources that's relating to the temperature and not just deicing in general. But if I need to, I will. It'll just take far longer. Once I know what minimum temperature I need to be at, I can calculate the rest. At this point, it's an intellectual exercise. And yes, I know it's more than just getting to the proper temperature, I also need to calculate the heat transfer rate and so on. If this turns out to be unworkable for whatever reasons, I'll post and say so. I just need the minimum temperatures and not some arbitrary numbers so I can move on with the rest of the calculations. Obviously, the lower the required temperature that will do the job, the less power required. Humor me if you will, if you know the answer or can point me to the right places, please give. If not, well...
  15. Okay, Point made and acknowledged! Get out of IMC or better, don't fly into IMC or best, don't fly if you know there's unavoidable IMC on your route/leg. BUT what if one got caught for whatever reasons, would heating the flying surfaces be enough to at least get the plane into a condition where you can at least have more options to extract your plane safely out of the IMC? The way I'm looking at this is the "heating system" would be switched on if you know you cannot avoid the IMC at that moment and once safely out of icing conditions and a quick check to make sure there's no ice left, switch it off. Yes I know there's the problem of ice debris hitting various part of the airframe, but at least you would still have some lift and ability to fly out of IMC in a direction other than "straight down". Think of this as "cheap insurance" and I do mean "cheap". I looked at the TKS technology and while I'm sure it's a good system, it add 80 to 100 pounds to the airframe, not to mention the $$$. The idea I'm mulling over is a lot cheaper and very light. Maybe at most add 20 lbs. Still doing a bit of research on this, but so far seems sound. This is not really intended to let one fly into IMC with impunity, although it may help prevent ice from accumulating/building up in the first place. This can be extended to cover the winglets and/or fuse as well if desired. If I can prove this as a sound concept, I intend to release this idea as a "freebie". In other words, I have no intention of trying to set up a company and market this. Especially since all of the components can be obtained locally and cheaply by the builder for incorporation into the build. This concept can also be used on other composite airframes. Drawbacks might be in the time required to heat up the flying surfaces (checking into this) and requiring somewhere between 5 to 10 HP while in operation. Deicing propellers is another whole issue, but one worth thinking about. What I really need to know is what would be the minimum temperature(s) needed to prevent and/or get rid of the ice?
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