Newbie question about electric vs gas

I'm considering trying to build a plane. Like an earlier poster, I'm definitely a do-it-yourself, crash-and-burn-a-few-times, kind
of person. I'm definitely not interested in joining a club.
I have four questions for you experts out there. I've tried to find answers to some of them, but the world seems to be divided into "electric" and "gas" and I don't see a lot of comparisons between them for the beginner...
First question: for a fairly small plane (maybe 24" wingspan, tops), what are the tradeoffs between gas/electric power? Is it even possible to take a plane designed for gas power and swap in electrics? Seems as if the battery weight forcomparable power would be a killer, but I don't have the information to work out the numbers, and some of you surely have the experience.
Second question: My guess is that electrics tend to fly at lower speeds than gas-powered planes. Can someone give me a guestimate of the speed for a trainer-type plane in both gas/electric? I live in a windy area, and if the plane can't make headway into a 20-knot breeze, it's probably no use to me.
Third question: Are electrics comparatively silent? I'm sure that there's prop noise, but I assume there's no high-pitched whine like with the string-controlled plane I had in 1965. Thoughts?
Fourth: Can someone give me a hint about the duration of flight for some low-end combination of batteries/motor/prop on a trainer-type plane? I *know* that's like asking "how fast does a boat go?", but for sailboats there actually *is* an answer: monohulls tend to go between 3 and 7 knots, with dinghies at the 3-knot end, and 40-footers at the 7-nkot end. An answer that's even as rough as that would make me completely happy. :-)
Thanking you all in advance,
-John Hughes
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Why not? You'll make friends, and flying with somebody definitely beats flying alone. Also, with an instructor, your chances of crashing are greatly decreased.

Gas - cheaper, higher power/weight ratio. Electric - quieter, more convenient. There have been numerous conversions. Usually a gas to electric conversion involves replacing unneeded plywood with balsa and lightening the airframe. Gas engines produce a lot of vibration that requires beefing up the structure.

Not necessarily true. I've seen some very fast electrics. Like gas, it all depends on the type of airframe, the motor and prop you use, and what kind of batteries you have. However, do you really want a fast plane? Fast planes need quick control responses, something you don't have when you have to think about what stick which way gets the plane to do what you want.

Electrics are very quiet compared to the mosquito-on-steroids sound of an unmuffled .049. Usually there is a little noise coming from the motor and prop, but it's much less than glow.

That depends on the motor and battery system you're using, and how you use your power. Typically, you can get 5-8 minutes with NiCd batteries, a bit longer with NiMH, and about 15-20 minutes with the new LiPolys. As they say, your mileage may vary.
I suggest you read up on electrics at www.ezonemag.com and since you want to design your own, a program such as MotoCalc (www.motocalc.com) would be indispensable. MotoCalc can calculate the performance for various combinations of airframes, motors and batteries.

Hope this helps, Morris
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| > Third question: Are electrics comparatively silent? I'm sure | > that there's prop noise, but I assume there's no high-pitched | > whine like with the string-controlled plane I had in 1965. Thoughts? | | Electrics are very quiet compared to the mosquito-on-steroids sound of an | unmuffled .049.
True ... but then again, that unmuffled 0.049 is probably louder than a muffled 0.46 too.
| Usually there is a little noise coming from the motor and prop, but | it's much less than glow.
If it's got a gear box and a larger prop, it's usually very quiet. Sometimes the gear box makes as much noise as the prop -- and that's not very much.
If it's a high performance plane with a direct driven prop, it can be pretty noisy. My flying wing with an Astroflight 020, 3 cell LiPo pack and a 6x3 prop makes a lot a lot of racket -- not quite as much as an 0.46 IC engine, but quite a bit. Of course, it's running at 22K rpm, so that's not unexpected. Of course, I could just throttle back.
(To be fair, an IC engine pushing the same prop at the same speed would make even more noise, because you'd also add the engine noise. But not all electrics are silent.)
--
Doug McLaren, snipped-for-privacy@frenzy.com
Can anyone remember when the times were not hard, and money not scarce?
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I can relate - I approached flying the same way... By the way, I did crash and burn, several times!

It's certainly possible to convert gas to glow, or glow to gas, although that's something that's best done _before_ the plane is built. Electric doesn't demand such a strong airframe, but will benefit from a lighter one (because of the battery weight you mentioned).

Sorry - I've not flown any glow powered planes to make a comparison (I've seen a very few flying). My electric Piper is pretty quick though, and a little heavy (it's my "high wind" plane). It may do around 20mph?

Comparatively, yes. Direct drive planes are very quiet - with geared motors you can get a little gearbox noise. The noise goes up with size - I have a 48" GeeBee Z that may be as loud as a glow plane.

I have two small foamies - I fly the Piper on NiMH for 20 minutes on a battery (and the batteries are cheap enough to buy two), and a Bearcat I fly on Lithium-Polymers. Some days I can't fly long enough to hit the end of that one...

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On 5/14/2004 7:08 AM Ted shuffled out of his cave and grunted these great (and sometimes not so great) words of knowledge:

First, The E-Zone http://www.ezonemag.com/ has a lot of VERY GOOD information.

Electric is quieter than glo. Because the noise level is substantially lower, they can be flown in areas that would normally not allow flying. The plane is clean after flying and less peripheral equipment for the field is needed. Unless you use brushless motors, power is usually limited. Electrics can be substantially more expensive than glo.
Is it even possible to take a plane designed for gas

It is possible and there are MANY glow to electric conversions. It is easier to do with a kit than an ARF, since you will need to lighten the airframe by removing pieces that aren't needed and/or substituting lighter wood in areas that do not need it due to the lack of vibration from electric motors compared to glo. The big thing to watch out for is the wing loading - how many oz of weight per square inch. The lighter the better, especially for electrics.

MOST electric trainers and park flyers have difficulty in winds over 5 mph. Electric trainers USUALLY have a top speed of about 15 mph and cruise at a slightly faster than walking speed.
MOST 40 size glow trainers have little if any difficulty in 10 mph winds, however, they USUALLY take off and land at ABOUT 25 mph, cruise at ABOUT 40 mph.
The simple answer to your question is: If you have 20 knot AVERAGE winds, learn on a 40 or 60 size glo plane. They will USUALLY have a 50 - 70 inch wingspan and weigh 5 - 7 lbs ready to fly. Because of the heavier weight they can handle the wind much better and their larger size makes them easier to see and see what they are doing.
The down side to them is: You need a substantially larger area to fly them in. A football field is way to small. They are louder than electric and you will have to spend about 5 minutes at the end of the day to clean them (no biggie - some paper towels and Windex). You will need more peripheral equipment at the field to fly them. You will most likely have to travel further to get to a flying field.

Electrics are USUALLY substantially quieter than glo. A good percentage (maybe 25%) of the noise is from the prop. More efficient props are a lot quieter. I have reduced the noise level about 8db on my 40 size planes just by switching to a more efficient prop.

THE MAJORITY of low end trainers/park flyers using BRUSHED MOTORS and a NiCAD/NiMH battery have a flight duration of about 5 - 7 minutes. With PROPER THROTTLE MANAGEMENT, that can be extended. Using brushless motors ($$$) and a LiPo battery ($$$$$$$), 30 minute flights are common.
Whether you want to learn how to fly using electric or glo I HIGHLY RECOMMEND the following: Find a club, and get an instructor.
It is possible to teach yourself how to fly, there are people who have done it. Teaching yourself to fly though, is a VERY STEEP learning curve and quite frustrating (not to mention expensive). The USUAL first flight for someone teaching themselves to fly is UNDER 30 SECONDS and USUALLY results in "rekitting" of the plane.
Remember, you have a prop turning at several thousand rpm, not to mention the force of the plane itself if it hits someone.
Hope this helps.

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| MOST electric trainers and park flyers have difficulty in winds over 5 | mph. Electric trainers USUALLY have a top speed of about 15 mph and | cruise at a slightly faster than walking speed.
`Electric trainer' is pretty vague, but even for most park fliers, your speed estimates are pretty slow.
Unless you're talking about a bonafide glider, even most mark fliers have a hard time flying under 10 mph. The Pico Moth is slower than most, and it stalls at 7 mph with a tiny battery pack. It's top speed is probably around 25 mph -- and most park fliers can go faster than it can.
| MOST 40 size glow trainers have little if any difficulty in 10 mph | winds, however, they USUALLY take off and land at ABOUT 25 mph, cruise | at ABOUT 40 mph.
That's probably pretty accurate ...
| The simple answer to your question is: If you have 20 knot AVERAGE | winds, learn on a 40 or 60 size glo plane.
Reasonable advice. Though if the winds really do average that high, and you have some sutiable slopes near by, I'd suggest Zagi-like slope flyer instead. They're almost indestructable, and a good deal cheaper as well.
--
Doug McLaren, snipped-for-privacy@frenzy.com
"I believe we are on an irreversible trend toward more freedom and
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Ted Campanelli wrote:

No, that is true of PARKFLKYERS, not electrictrainers in general.
I have a speed 400 trainer that lands at 15mph, and cruises in teh 30mph range. Well able to cope with wind SPEED, but the smaller size and weight means it does flip about in turbulence.
Even parkflyers generally can achivew 20-25 mph, but its a struggle flying in even a breeze.
I have a overpowered spepd 480- plane that lands about 16mph, and is capable of at least 60mph on the flat. Its flyable in winds, but I tend not not because winds = clouds, and clouds=low light and the darned thing is a dot before I can wiggle the sticks to brng it round :)

If yoi can., however a recent poll of most of the electric flyers on the ezone revealed that the majority of them were self taught.
I tried teh glo/club/instructor route, but it was totally unsatisfactory. I ended up crash and burning my way through a few electric models and G2 flight sim,. and now can more or less fly a model adeqyuately enough to get it down in one piece most of the time :-)

Thats where G2 flight sim is teh bees knees. Unrtil you can reliably fly a plane on that, don't try flying anything other than a cheap parkflyer.
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The biggesst tradeoff I see is money!!!!! I bought a 3 phase electric motor with gears and a speed controller, whiz bang battery charger $$$, special prop and adapter/spinner,battery pack, .... it may not stop here....many $$$$ involved and that doesnt include the airplane nor radio. Probably 500 $$$ so far. I could have bought a real nice glow engine for that. 4 stroke.
John F. Hughes wrote:

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Thats true, but kinda 'apples & oranges' A 'stock' electric drivetrain costs squat, and performs adequately in most cases. Ive 3 GWS planes and all seem to have enough power for normal bashing about. A 'stock' .40 isnt that expensive either.
A brushless Razor with a fat lipo pack and all related goodies for the flyer looking to break the 75mph mark is kinda along the same lines as saito 4stroke or a pylon racing engine with pipe. Entirely unnecessary for us average shmucks.
to the original poster: Your situation almost eliminates the "self-teaching" route. If it wasnt so windy it'd be easy to suggest a Slowstick (electric) or maybe a Nextar (.40 glow) and have a go at it. But the 'Stick wont fly at all in 10+mph wind and the (any for that matter) glow plane really is kind of a handful for a total newbie. Add wind and your chances for success dwindle.
I self taught on a slowstick (in 3-5 mph winds) and it was maybe 15 flights - each progressively longer - before i finished out full battery before crashing. Took maybe 2 months to get the hang of it - mostly because GWS spare parts are hard to come by these days. I graduated to a high wing aileron electric trainer (GWS Estarter), and then a beat up ol' .40 trainer. Both are not exactly easy to fly, but ive only ever crashed them due to mechanical failures. If i hadnt trained my thumbs properly first on the slowstick, they would be very difficult.

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[lots of useful stuff, from this poster and others, deleted]
I'd like to say "thanks" to all the folks who took the trouble to answer my naive questions. The answers -- even when they disagreed with each other -- were very helpful, and I appreciate the time you all took.
A couple of folks asked "Why don't you join a club?" and the answer there is simple: I know myself, and I don't do well in clubs. If clubs are, indeed, the only way to go, then I'll take a pass and keep messing about with my (too many other) hobbies. But it sounds as if I *might* get the fun I'm looking for from a small park-flyer, self trained.
Wind conditions *are* a big issue where I live -- almost every summer afternoon there's a 20-knot breeze from the SW over Narragansett Bay. Of course, I could go with early-morning flights, or fly only on godawfully cold and still winter days, but somehow that doesn't seem ideal. :-) I *could* imagine that this hobby might make a nice compliment to iceboating, though, where I often go out in winter *looking* for a breeze and find none and stand out there on the ice praying and stamping my feet.
---John Hughes
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John F. Hughes wrote:

John, no you have added the extra information, I can make a couple of recommendations to you.
(i) Get realflight G2 flight simulator. Its hours of practice for the cost of one plane, and you can crash and be up again in seconds. It will alow you to get aome feel for wndy conditions as well.
(ii) Consider a slope soarer or electric sailplane. There are many that, with a bit of down trim, will fly extremely fast. Yet still be sufficiently sedate to land safely for a beginner.

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wrote:

John, To really get you started in flight sims you could download FMS. http://n.ethz.ch/student/mmoeller/fms/index_e.html
Though I don't think it has the same setup for wind conditions or is as acurate as sims such as realflight, you will probably catch the flying bug even sooner. ;-)
-- "Don't call me a mindless philosopher" Max Gaming and Brown Paper kite site http://www.mis.net.au/max
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I think you might be surprised at the variety of people in most clubs. Flying clubs are probably the most un-club atmosphere you could imagine.
-- Paul McIntosh http://www.rc-bearings.com
wrote:

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Paul McIntosh wrote:

I certainly was, when a box of crystals vanished from the top of my flight box, never to be seen again.
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wrote:

I think you're missing the point - there are those of us who simply dislike being around a bunch of other people, no matter how nice they may be. Personally, I taught myself to fly using a Slow Stick in a fairly short time. I had considering joining a club, but when I look at things like their meeting minutes, it pretty much just turns me off. OK, fine, 4 guys showed off their newly-built models - but personally, I don't really care what other people are building, or how nicely they did it. I didn't want to be learning how to fly while surrounded by bunches of people, etc. I'm generally not interested in watching other people fly - I fly because *I* like it - and the only reason I would have to watch someone else is to learn something new. In the few times I've stopped by local fly-ins, well, the most charitable thing I can say is that I didn't see anything worth emulating.
I suspect there are a lot of people like me out there, but we refuse to take surveys, too. ;-)
- Rich
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No, I think YOU are missing the point. Your involvement with the club is determined by you. If you don't like the meetings, don't go. There are days at most club sites that have no one around for hours. There are days when it is far too crowded. You can't uderestimate the power of one good instruction session!
-- Paul McIntosh http://www.rc-bearings.com
wrote:

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wrote:

You also can't overestimate the damage of one bad instruction lesson. ;-)
Personally, at least when it comes to park flyers/electrics, I honestly don't see what the big deal is in regards to learning how to fly by yourself. A Slow Stick is nigh-unto impossible to break. Spend a few hours building some muscle memory for handling control reversal, get a cheap aileron trainer for the next step, and the next thing you know you're buying a Tantrum. :-)
- Rich
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Ok, you are right all clubs are universally bad so we should all avoid them on the off chance that everything isn't perfect.
-- Paul McIntosh http://www.rc-bearings.com
wrote:

is
days
good
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Paul McIntosh wrote:

Don't be more stupid than you have to be, Paul.
Did you learn to drive a car by going to a go-kart track?
Do you inmediatelt yearn to take your car to a crowded motorway to drive it?
Or to an empty country road?
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Excellent point. It really strikes me as odd how much the whole "You can't learn how to fly without an instructor/Join a club or you'll never learn" crowd keeps trumpeting their message. And then when someone says, "Well, I taught myself", the response is quite often "But yeah, that's very unusual" or "OK, but you probably only THINK you know how to fly well", etc.
Seriously, it just *isn't that hard* to learn with a slow, forgiving airplane. It's like having a bike with training wheels. And, last time I checked, airfoils and control surfaces obey the same laws of physics on a park flyer as they do on a gas-powered scale model, and your skills ( once you've acquired them ), are just as valid on either machine. Sure you're going to bust up a few planes. But it seems to me that I read about an awful lot of experienced pilots busting up their planes here - not just the newbies.
Personally, I have to wonder if the attitude stems from some need to pretend that the hobby is harder than it actually is, so people can make themselves feel important.
Now, granted, it's very useful to go into the whole learning process knowing a little bit of aerodynamics, but personally, I found that the most difficult part was just developing the muscle memory to move the sticks correctly, no matter the orientation of the airplane. And that's something that ONLY you can do - an instructor can't learn it for you.
- Rich
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