# Hello from NZ!

Discussion in 'New Member Introductions' started by RCBinChicken, May 20, 2019.

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1. May 20, 2019

### RCBinChicken

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Hi all! I've hurriedly joined this forum, after Google found me a good discussion you guys had on the subject of Scott Winton's Facet Opal.

I'm an engineering student from New Zealand, studying electrical presently but trying to pick up whatever I can in terms of mechanical and other disciplines, with the goal of one day building and flying a homemade, electrically-powered ultralight (and making myself more employable along the way, though I'll freely admit that's a secondary consideration. )

My only aviation experience thus far comes from building and flying RC model aircraft, which I'm aware is no substitute for the real thing but will hopefully give me some overlaps of skill/knowledge areas if I persevere with it diligently.

I have never been a wealthy individual and I see that as unlikely to change drastically throughout my life as I'm a naive, whimsical soul and tend to value time higher than money, so my ultimate goal is to get myself in the air, very, very cheaply; secondary goal, a plane that's easy/cheap to transport and store, so minimal overall dimensions, especially wingspan. I'm really not too concerned with pushing the far edges of the performance envelope - in fact, I'd ideally be flying slowly enough that I'd be unlikely to be crippled/killed in the unfortunate event of a CFIT! I'm also aware of the horrible energy density tradeoffs between lithium-polymer and gas, so range and endurance is also (relatively) out the window.

I'm inspired/made hopeful by the work of Mike Sandlin and his paramotor-powered, 40km/h-cruise Bloop-series "motorfloaters" - http://m-sandlin.info/bloop/bloop.htm - and people like the above Scott Winton and Peter Sripol, just in terms of demonstrating what's achievable with moderate-to-small wingspans and low-output power systems respectively, and overall (with the exception of Mr Winton, obviously) low-tech build materials/methods.

(I feel like from what I've stated goal-wise, a fair few people are going to read it and say "kid, what you want is a paramotor", and while they would be objectively correct in that, paras just don't excite me. I'm a strict fixed-winger at heart.)

I'm not really sure where to start, I have a million billion questions (and an uncomfortable awareness of my own lack of expertise and that accordingly a pretty good majority of them will probably be stupid questions) but if there's anybody on here with an interest in similar craft, or knowledge of similar projects, I'd love to hear from you. Or even if not!

2. May 20, 2019

### akwrencher

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Welcome to the forum!

If you haven't yet, spend some time looking through the different areas of the forum and getting familiar with the threads in progress. You are definitely not alone in wanting simple cheep flight, and there are others active on here that are into electric. Also the stickies are very informative. Some very knowledgeable folks on here that generously share with the rest of us less schooled and experienced.

3. May 20, 2019

### noob8844

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Shalom!

I'm also an engineering student (Aero/Astronautical) from the U.S. and I think we have a lot of overlap in our goals. I'm currently designing an easy to build and disassemble (and thus store/transport) all wood ultralight. I have no experience making RC craft, so I'd love to cooperate with you if you're interested. Somewhere down the line I'm going to need to make the model and see if it can actually fly without crashing horribly, and it would be great if we could cooperate on that. Additionally, I'm still looking into power plants, so I can be persuaded into making this thing fly electric, if you had something in mind. Here is a screenshot of what I have so far

The wingspan is somewhere along the lines of 11 meters, but each wing is split into three sections for disassembly and transport. I was told earlier however that a wood cantilever wing would be too heavy to make, so the design may change... a lot. Let me know if you, or anyone else, is interested. I lack a lot of experience/practical aspects of designing and building planes so I could use the input of other pilots, woodworkers and aircraft technicians.

4. May 20, 2019

### RCBinChicken

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Will do! Even just in the time since I made the above post, I've found several threads that had highly relevant info, and even a few similar examples - I'd never heard of Les King's "Primmer" before today, but its layout is encouragingly similar to what I was imagining. This place is awesome!

5. May 20, 2019

### RCBinChicken

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I have no experience with wood for the model side of things, other than for spars - I'm a foam junkie! - but happy to help where I can on the general idea. Your overall layout, materials aside, looks pretty sensible to me, it should be doable as a model. The more experienced guys here may spot lots of things I can't, though - I'm by no means an expert on the RC side of it, I just know even less about full-scale!

Wood cantilever seems to be tricky, yes - I gather that with a decent wingspan, the spar you need to resist the root bending moments ends up fairly chunky. My own project is currently leaning towards a wooden main spar, but a much shorter total wingspan (6.5m, maybe 7m max) and a taper - basically a cropped delta planform - so the bending moments at root would be greatly reduced. Plus the wing can be made quite thick at the root, so structural strength is easier to achieve (my plan is for the plane to weigh less than the pilot, and I'm not a very large individual myself, so the G-loading requirements on the airframe should be minimal.) A cropped delta planform comes with its own host of problems, though, which I'll just have to grit my teeth and deal with, so a more conventional layout like yours has a better running start I think. There have certainly been all-wood cantilever monoplanes in history!

RE: electric power, I think whether it's worth pursuing or not would depend on what you want out of your aircraft. My goal is fixed-wing flight, above ground effect, in something self-designed and very cheap - I don't care if I'm pootling around at a slower speed than a decent moped, or if my flight time is less than 20min. (Plus at the lighter/low performance end of the scale, I can stick a fair few batteries in by capitalizing on the weight difference between gas and electric powerplants, which offsets the horrible energy density of LiPos vs gasoline just a little.) But if you want any kind of endurance, without spending most of your monetary AND weight budgets on batteries, gas may just be easier.

As said: take all of above with a grain of salt, I'm also a noob. Feel free to post some more details on your design if you feel so inclined, and I'll have a hunt around my drawings and see if I have anything up-to-date of my own design that I can post here - unsurprisingly, it gets a redesign every time I learn a new principle. >.>;;

6. May 20, 2019

### Victor Bravo

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RCBinChicken WELCOME to the place where you're never alone in wanting to discuss inexpensive or clever solutions to getting in the air. Even those of us who have "normal" airplanes are still greatly interested in brainstorming about new ideas, less expensive ways to fly, etc.

On behalf of the many many old model airplane builders on this forum, believe me when I say that ALL of the experience and effort you have put into models is 100% valid and useful. It certainly does not substitute for formal engineering education, but an engineering degree doesn't substitute for the thought process and hands-on experience of models either. There is a time and place where each of those things is the right tool for the job. So do NOT ever think that your experience with models is irrelevant or "secondary", but also don't ever think that what is designed correctly for a model is good enough to be safe on a full size aircraft either

Also understand that building an aircraft and flying an aircraft are two separate hobbies, two separate skills, and two separate rewards. Building is not the cheapest way into the air when you actually put real-world numbers down on paper. In many cases, the costs of building an airplane can be spread out over a long period, and make it easier to afford. But in almost all cases it will have cost more (in money and time) than buying a used aircraft.

7. May 20, 2019

### Dana

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I've always said that I learned far more about real world engineering in the basement building R/C models that I did earning an engineering degree.

As a long time fixed wing pilot I was unimpressed with paramotors, too... until the third or fourth time I saw one, then something clicked... they're a hoot! Flew 'em for 5 years or so, then drifted back to airplanes.

8. May 20, 2019

### Dillpickle

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9. May 21, 2019

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Model builder here too. The big thing that stands out to me is the much higher construction density of full size aircraft compared to the models. Models typically use very light structures with lower wing loadings and much higher thrust to weight. This makes things like spars etc in full size, need an order of magnitude higher strength.

10. May 21, 2019

### RCBinChicken

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Thanks VB! These were things I'd suspected, but good to hear them confirmed by someone who's walked the walk. I've built plenty of awful models that I could get to fly by "brute force" (excessive power-to-weight, maneuverability and constantly riding the sticks) that I'm sure would have killed me instantly (and likely a few innocent bystanders) if scaled up to human-size. >.>;

And my time in the hobby so far gave me a good parallel and boot-camp of your second point, too: I've never bought a ready-to-fly or a kit/ARF, and only even built from plans once, the rest have been self-designed scratchbuilds, and the only way it worked out cost-effective (over the regular RCer who buys their models) was if I assigned NO monetary value to my time! If I had to pay myself even half NZ's minimum hourly wage, I'd be waaaaayyy further out-of-pocket than the poor goofs who buy a $700 scale warbird for their first RC model and tip-stall it into a million pieces on the maiden. I expect the same holds true for the real thing, and then some. I've seen very basic, bit-of-work-needed-to-fly second-hand microlights go for less than NZ$2k - I know that anything I try to build will likely be double that just for batteries.

On a more specific note, I saw some of your posts about the Pelican plank-flying-wing in the Facet Opal thread, and while I'm not looking to copy it exactly - the design aspect seems to be what my brain finds the most fun - it's similar enough in layout to what I had in mind to serve as a really good comparison/baseline, as is the Opal itself (though I'm NOT going for high speed/performance, don't worry!I intend to fly at speeds where crashes will damage my ego less than my aircraft.) I got the feeling that the Pelican's a bit of a favourite of yours, so if you feel like having a good ramble about it, I'm an eager audience!

11. May 21, 2019

### RCBinChicken

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That's a very good point, I may yet be seduced by their flapping, rubbery appeal... which is just one more thing that's great about Mike Sandlin's setups, because if I have a good e-paramotor rig, I won't have to choose, I'll just swap the powerplant from one craft to the other. (Which appeals to me as a habitual cheapskate, as I already do that with my RC builds. I buy a couple of good-ish motors and make quick-swappable mounts, rather than have to buy a motor for every plane.)

12. May 21, 2019

### RCBinChicken

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Nice! Yes, that's the direction I'm most leaning toward, at my current knowledge level - wood for vital structure, foam for shape/everything else. (A million options abound for what I'd cover the foam with, though. I'll need to do more research in that area!)

13. May 21, 2019

### RCBinChicken

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Absolutely, the square-cube laws out-muscle us, as surely as an ant out-muscles an elephant relative to respective size. Every time I look out of the RC foxhole into the full scale one, I think "yeesh, we have it easy, I'd better not get complacent!" Another reason why I'm wanting to go for a low-AR delta with its bonus of higher allowable wing thickness... though deltas seem to bring another difficulty to the table with them, for every one they take away.

14. May 21, 2019

### pwood66889

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" as surely as an ant out-muscles an elephant relative to respective size. "
Mammal muscle is a bit stronger, ounce for ounce, than insect muscle I have heard. Problem is getting an ounce worth of ant!
But belay that. Welcome aboard. This is the place for ones who strive. I came up through General Aviation via the US Air Force, and think you will become a valued contributor. We tend to discount new thinking sometimes over much.
All the Best = Percy in NW FL, USA

15. May 21, 2019

### Victor Bravo

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I saw Les King's "Primer" fly in person several years ago. So did BobK (I believe), and probably a few other HBA'ers. Murry Rozansky, a new HBA participant but also the president of the ESA, also might have been there when Les flew it that day, at the SHA/ESA workshop in Tehachapi.

Les built it as a proof of concept, with no concern whatsoever for flight performance or anything resembling soarability. He was experimenting with methods and materials and build time and cost. It was also completely disposable, with no effort put in to making an airframe that would last any longer than a handful of test flights. Peter Sripol's foam biplane has a DC-3 airframe service life compared to the Primer.

The glider flew safely enough (with a combat veteran pilot at the controls), but it flew somewhat poorly in terms of it being suitable for any sort of fun flying. I would not suggest holding the Primer up as an example of a successful design, and that is coming from someone who really admired Les and considered him a good friend.

The Mike Sandlin approach (Bloop, Bug, Floyd's E-Goat, etc.) would serve you far far better in terms of getting a usable flying machine that lasts a while.

I am indeed thinking and scheming and plotting and sketching about building a version of the Pelican. Not an original Pelican either, but a sheet metal version for a more robust airframe (I have a good safety margin against malnutrition). It may not meet the Ultralight or Microlight weight restrictions in any given country, but I have a regular pilot's license and medical so it is a non-issue for me. But my idea to build a "tin" Pelican means nothing, my mind and my circumstances change on what appears to be a daily basis.

16. May 21, 2019

### mcrae0104

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If you like foam, you might also want to check out the Rutan composite video and the Mike Arnold videos that are on YouTube.

17. May 21, 2019

### RCBinChicken

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Thanks! I'll do my best to live up to that! And you're likely right on the muscles... ant strength is just often held up as an applied example of the square-cube law, which I guess is all the more impressive if their muscles are less chemically efficient than us larger-meats.

18. May 21, 2019

### RCBinChicken

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Warning taken RE: the Primer. Thanks! To be honest (and shallow) I just liked the shape of it from the couple photos I saw (and would likely have deviated from that a fair bit too.) Yes, Mike Sandlin's setups seem like the clear winner for most of the qualities I want in a plane. Again, the idea of exactly replicating one doesn't excite me - ditto for bipes in general, sadly - but I'll be trying to find as much overlap as I can between what I want and what worked for him.

My sympathies on Pelican-related indecision - my mind changes daily on what RC build to pursue next, and the constant back-and-forth weighing of pros and cons is realistically my main obstacle to actually building anything. I'm hoping that the exponentially higher monetary and time investments required by full-scale will force me to commit and stick to things, but it may just prove a similar-but-far-more-expensive dithering addiction. But suffice to say, if you do commence a tin Pelican one day, I'll be watching avidly! It's a fine looker.

19. May 21, 2019

### RCBinChicken

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YES! I learned about Mike Arnold's work recently and watched a couple of his videos, was blown away - especially his simple, matter-of-fact explanation about adverse pressure gradients as "nozzles". Amazing guy! Haven't watched the Rutan one yet but I've long admired Rutan's work (who hasn't, I guess) especially the VariViggen, which got me all excited because it was coincidentally similar to one of my first few RC models. Indeed, the design I'm sort of flirting with currently would be cosmetically similar to the VariViggen, but canard-less, a lot more wing area and much lighter weight, intended to occupy a similar ecological niche to the Bloop in terms of low power and low wing-loading. (Disclaimer: I have gathered that a delta is likely a HORRIBLE choice for that flight regime, so a lot of the work I'll be doing over the next few years - with study, quizzing smarter folks, and building increasingly large/heavily loaded RC scale models of concepts - is finding out if there are any usable gaps in that lump of horrible. I love deltas too much to give up on them.)

20. May 21, 2019

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