Spectra - Spirit??

Well, after sitting up to 2:30am this morning(yawn!) searching Google Groups I've basically come down to these two planes. The Spectra being motorized and the Spirit un-motorized (specs listed below).

Looking at their specs, the Spectra has 50% more wing loading than the Spirit, whch I interpret as being much better for thermaling. But, how are these wing loading specs are arrived at? Are the specs figured with radio equipment included? For example, the Spectra is motorized...is the wing loading figuring with the batteries, motor, and all other electricals included? Is the Spirit which has no electrical equipment installed in ARF kit figured with radio equipment or without radio equipment? I guess what I'm trying to figure out is...is wing loading specs determined/stated for the complete, RTF state of a plane including all hardware and required equipment?

In regards to the Spirit, what would be a good radio setup for it? I'd like at least a 4-channel transmitter, nothing fancy, but something I can use with other/later planes. Would mini or standard servos be best?

Thanks again! Ed (in south Alabama where the buzzards fly!)

Great Planes Spectra: Wingspan: 78.5" (1995mm) Wing loading: 10.6 oz/sq ft(32g/sqdm2) Wing Area: 676 sq in (43.6sq dm2) Aspect Ratio: 9:1 Weight: 3.1 lb (140g) Fuselage Length:37.5" (953mm) Dihedral: 4-3/8"

Great Planes Spirit: Wingspan: 78.5" (1995mm) Wing loading: 7 oz/sq ft(20g/sq dm) Wing Area: 676 sq in (43.6sq dm) Aspect Ratio: 9:1 Weight: 2 lb (910g) Fuselage Length: 39"(1000mm)

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Seems to me, the wing loading is not a 'spec' per se. It is derived by dividing the flying weight by the area of wing to get a quanitzation of weight per unit of wing area. The reason the Spectra has a higher wing loading is because it is heavier -- when you factor in motor, bigger batteries, etc.. From there, logic would indicate the Spirit, because it does not have the load, will be the better 'floater' for riding thermals. The Spectra is a fine airplane. Better than some and not as good as others. I am a glider purist. I don't and never have owned a powered-glider, so I'm not the ultimate authority on ships with spinning things hanging on the front. In your original post, you mentioned a dearth of thermals in your area. I challenge that. Thermal engines are any two adjacent surfaces on the ground of different temperatures. A good example is a tennis court surrounded by grass. The larger the delta-T the more energy in the thermal. The buzzards you mentioned are a good clue. The average turkey buzzard weighs more than 12 pounds. What is your Spectra going to weigh?

Have fun.

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Casey Wilson

Howdy Casey. I think my wording was a little askew in my remark about the wing-loading. I did take it to be that the Spirit would be the better thermal flier, being lighter. I'm somewhat leaning towards the Spirit but getting it up in the air has me concerned. Is a high start difficult to make work for a beginner doing it on his own? Now, I know that the general consensus is to go to a club somewhere and get an instructor, and I can see the wisdom in that, but in my case time is very much at a premium...trying to run a business by myself that my father, brother, and I ran just a very few years ago... Things change quickly. I'm simply looking to grab some time on the weekend, drive across the road to a hay field and (hopefully) fly.

I fly kites some and have sailed some small sailboats in the past...I really like the idea of unpowered flight...just the sound of the wind and air.

The area I have to fly in is about 45 acres of hayfield and it is also the top of a large hill. It's basically in the center of a pine plantation with the southside of the hayfield sloping down. Would you think there's enough difference in temperature between these two surfaces to create thermals in a somewhat consistent manner? The buzzards do seem to like the area.

In regards to the buzzards...it seems I'm on a constant look-out for them here lately!


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"intheswamp00" wrote in message news:40f343b5$1 snipped-for-privacy@news.vic.com...

My thought is the thermals will be generated by the temperature differences between the hayfield and the piney woods (Texas Talk). If the hill is more than just a knob, like maybe a ridgeback, and if the wind blows mostly into the side of the ridge and not parallel, you might have a good slope soaring chance. Here again, if the winds are just light breezes, the Spirit will work best. On the other hands, if the breezes are enough to fly a stunt kite, the heavier Spectra might be the best. It depends on the energy involved. You can always add ballast to the Spirit. I carry a few Bull Durham bags of lead shot in my kit. I once saw a flyer tape a 12-inch pipe wrench to the bottom of his glider to make it heavy enought to fly off a cliff in California. The answer to the Hi-Start question revolves around your experience. You haven't said anything about that, but your first post hints of some exposure to the hobby. If you don't some experience, the first launch will rapidly fill your bladder. You can expect the ship to bolt almost straight up when you turn loose! Don't get trapped into thinking you'll just pull it back a little bit the first couple of times. Without enough energy in the launch, the hook won't release and a crash is almost inevitable. I know you've done a lot of looking at the Spirit and Spectra and they are fine ships. I have three Spirits (well, one that's flyable, anyway). But have you considered a foamie, an EPP glider? The basic indestructability of a foamie makes it well worth the extra cost of another ship. My grandson ploughed my TG-3 straight in from about 40 feet up. I straighten the wings and launched it a minute later. I've bounced it off hockey goal posts and fence post and a utility pole. It is the ugliest ship at the field, but it still flies. I've seen a lot of discouraged newcomers spend more time repairing gas-bags than flying them. It happened to me. I was ready to quit but my son wouldn't let me. He kept repairing the wings, gluing on the rudders, splicing the horizontal stabilizers and dragging me back to the field. We were doing it alone, without an instructor to help. If we'd had a foamie, we'd have had a lot more fun, a lot quicker. That said, the Spectra will probably suit you better than the Spirit to start with. By the way, the thermals the buzzards are riding are being created up wind from where they are. The higher they are and the stronger the breeze the more the thermal tilts downwind. Go upwind to find the thermal at the ground level.

Have Fun!

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Casey Wilson

I have had my Spectra for 13 years. Never had a Spirit.

The Spectra does thermal although I doubt as good as the Spirit. You can't thermal very good if you can't get the plane up high enough. I've used high starts with gliders and never got a thermal. Can't ge it high enough up. I'm sure better sailplane pilots can. I've had lots and lots of fun with my Spectra. Every time I fly it know it will go up high, real high, and even if I don't find a therma I still get at least a 15 minute glide back down. I've recently upgraded to a Jeti 16/15/4 brushless motor and mor recently to a lipo pack (TP 3s 2100) which saves 5.1 oz. of weight ove the 8 cell 1700 nimih's . This combination basically shoots i straight up, although I don't like to climb straight up so about hal throttle is enough. My plane ready to fly weighs about 48 oz

-- Foamaholi

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Wing loading is just the weight divided by the wing area. All up weight is the only thing that really matters, so it includes an estimate of how much the radio gear/motor, etc. weighs.

Low wing loading make a plane slower, and usually (but not always!) means lower sink rate. Heavier planes are more stable in the wind and will run farther and faster, opening up more days for thermalling. You can always weigh down (ballast) a light plane to make it more appropriate for the days conditions.

There are thermals everywhere, all year, (almost?) every day. You will fly through many, many thermals before you begin to see how the plane reacts to them and learn to ride them. Do not get discouraged. Find a local club and watch someone while they are flying. Ask what the pilot saw when he begins circling in lift. (Finding a club -

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then Charter Club Locator - even the "power" guys probably have a few "outcasts" who run sailplanes sometimes)

I have flown a Spirit many times. They are nice planes when properly balanced and trimmed. Then will float when you need and run better than most think. Just be careful if you fly low and upside down! OOPS.)

Electrics are nice because you do not have to bring out launch equipment, but highstarting an unpowered glider to a 15 minute flight will leave you feeling as high as your glider went. A fellow club member (with bad knees) flies nothing but electric and has a nice Spectra that he regularly puts in the air for half an hour at a time. The downside is that they fly faster and are more difficult to land in tight spots. Important if you have a field like ours.

A decent radio should have at least v-tail mixing available. FM is preferable and most common. The Hitec Eclipse 7 is a nice 7 channel (hear me out) with 7 model memories that will handle most of your needs for a long time at a reasonable price. It comes with full NiCd rechargeable batteries and a receiver and 4 servos. Don't worry about the minis or micros yet. The little weight gain is not going to change it into a slug. I have experience with the Eclipse, but other similar types are worth the extra investment if you stay with us. I also have two Futaba 4 channel Skysport Transmitters gathering dust! They do not progress into complicated models well.

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Thomas Koszuta

Piney woods. Yelp, that's Alabama talk, too...just some folks don't understand it. The difference in temps may actually have a seasonal variance, too. When the grass dies in the winter and lightens it's color the difference in temps of the dark green pines and the dead grass should create a larger difference. ???

Well, the site has the slope to the south, prevailing winds come from the SW. There's a long bottom running in the...bottom. The bottom is aligned a touch SW so the winds do appear to have a channel that they can follow to the small ridge. In flying the stunt kites, the crest of the ridge is the best area for some fun. Good wind there...when there's wind. More wind in spring and fall.

Now, as for as wind goes...it's sporadic here in south Alabama...wouldn't be a good place for RE windpower. This summer has been rather turbulent with the weather systems that we've had...thunderstorms, etc.,. I guess, as far as wind goes, disregarding approaching storms, we have as a rule mostly gentle winds...much lighter than gulf/ocean breezes.

My experience is VERY limited. Last Sunday I flew a "Shun Da Accipiter Badius" that I got off eBay. Not your quality plane, mind you, but it flew! Actually it flew the first time I launched it, but of course not knowing what I was doing it was on the ground pretty quick. I launched several times more and had some minor groundings. It was went I got a bit higher that the problems started.

The first time I pulled the nose out of the ground and got the dirt off the prop I noticed a little compression damage and the canopy had popped off. But, even with the canopy off we launched again. This time I flew it around the field for probably 5 minutes and then started gaining altitude. I was beginning to get the knack of it...yeah boy, you can do it!

About that time I must have got into the upper airstream....musta been at least 30 miles high! But, I hit turbulence and the un-canopied battery jumped out of place and was hanging underneath the plane. Immediately I started hollering MAYDAY MAYDAY ...___... ...___... and though kinda awkward, continued to fly. But, alas, we hit more strong wind...the reknown "Accipiter Badius" bowed it's wing back like a hawk going in for a chipmunk and it was "EJECT EJECT!!!".

Too late...the plane started a semi-spiraled nose dive, just screaming to spear the ground...and it did. Ever notice how a plane sticking nose first into the ground kinda looks like a tombstone cross? Flying was over with my Chinese plane for the day...one of the battery leads had been snatched loose from the battery pack. Got back home, glued some of the styrofoam packing innards back together, resoldered the battery lead, straightened out some of the crumpled fuse, and cleaned the dirt and grass out of the prop. Still need to put some strapping tape on the wings and it'll be ready for the weekend...my kite-flying buddy is dropping in for the weekend! :)

Now why I made you read through all of that, I don't know, I'm a grown man...maybe I've been at work to long. But, that's my flying experience. I think most of my problem was in a newbie over-controlling. I figure I can fly that plane into the ground (that didn't sound good and besides I've already done that a time or two) before I put a nicer one in the air. I guess you could say that I bought this little plane figuring it's finite life expectancy.

I probably should have looked a little further before I bought the Shun Da and looked harder at the foamies, but hopefully the plane will live long enough for me to get the hang of things.

Well, I'm leaning towards the Spectra...it seems more simple than using the high start, but yet the use of the high start sounds interesting, too. Thanks for the tip on using the high-start...I had thought just what you mentioned..."I can pull it back just a little bit to see how it works...". Wow, that would have been rather, er, amusing is not the word I'm looking for, but I think you know what I mean.

Sounds like you've got a good son...and one that definitely wanted to keep Dad interested! :)

I think your right on your thoughts about the Spectra suiting me better. I can start out easy with powered flight figuring out manuvering and then start working on my gliding and chasing thermals. Yelp, I've about come to the same conclusion.

Thanks a lot for the tip on the thermals tilting...I hadn't thought about that.

Now comes the question of....

With the Spectra what type of radio/servo system would be best? Standard or mini servos? Best places to buy the electronics at? I really wouldn't mind getting a fairly good radio...4-5 channel in case I decide to use it with other planes down the road, but nothing extravagant. For now, I'm figuring on the ARF.

Thanks, Ed (the crumpled accipter will fly again!)

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Great report, Ed, and a great beginning. That's what most of it is all about. Keep having fun 'cause the minute you take yourself serious... well.... Tell my you did a dozen or so hand tosses and balanced the plane on its spec CG before you ever pushed the throttle forward and made the prop spin. You did, didn't you?

Truth is, I don't think you should start with the best, basic is what you want to start with. Most of us have more than a couple of transmitters. In that department, I suggest starting with a basic 4-channel, maybe even on the upper price side. It's a good idea to get one with a 'buddy' connector. That way you can practice on your PC with any of several flight simulators. When you step up the line in aircraft, then step up to the Xmitters with bells and whistles. I always look for a receiver that will operate all the functions in my airplane and no more. That receiver will generally live in that ship for as long as it or the ship lasts. It will be a long time, a really long time, before your flying skills become so good and consistent that the negligible weight difference between good inexpensive servos and micro-hitorque will make a difference. I am a great proponent of the KISS principle. I'll get flamed for saying this, but Tower online is a good source -- presuming you don't have a local hobby shop within ten miles. If you do, then shop there. It may cost more, but the response and future service will be worth it.

Reply to
Casey Wilson

Yelp, Casey, I had fun. The tinkering around with it before flying was fun and then the "figuring out what I was doing" was fun. I love to tinker with things...though I haven't operated in a while I'm a General class ham radio operator...KF4KRV. Lately I've been tinkering with alternative energy for a remote cabin we're building. The ham radio is for fun, the AE...well it's kind of a necessity for the cabin, but I enjoy it. You mean there's folks that actually work with RC planes "not for fun"???

I must honestly report that I didn't do any unpowered hand tosses. I gave a little power to begin with and the plane flew suprisingly well (straight line). I did check the little Chinese plane for the center of gravity and made sure it was where I'd read the standard location was for it...1/3 behind the leading edge...the instructions stated nothing about CG. I basically I rested the wings on the tips of my fingers at the plane's "assumed" CGI and it looked to be balanced pretty good. I also checked the control surfaces and trimmed them out using the clevises on the the control rods.

Well, this weekend after a day in the swamp (building a small cabin down there), my brother-in-law, nephew, and myself took the Chinese plane out to the hayfield. Basically crashed and crashed. This appears to be a plane that can't take much wind at all. When it'd fly into the wind it'd take on the "hawk attack" attitude by folding it's wings backwards, it would thenbegin an out of control descent. I'm going to do some gluing and straightening, solder in a new on/off switch that came apart and take it back out at a *calm* time and see what happens. I'm beginning to wonder if using the transmitter might be harmful to my future flying....the controls are: elevator=left stick, rudder=right stick, and a little up/down switch located on the back of the righthand side runs the throttle/power. Not exactly a regular transmitter.

Posting a new question to the group about transmitters. Basically looking at the JR XF421EX and looking for opinions on it. In one setup it comes with four 537 servos and the 610 receiver. In another setup it comes with two 241 servos (micro) and a 610M receiver. The 2-servo setup runs about $20 less than the 4-servo. What do you think?

Thanks, Ed




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