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Geoff_Gino
12-08-2005, 02:49 PM
Hi All

I have aquired a Thunder Tiger Soaring Star.

2 metre wings
4 channels (ailerons - on seperate channels for spoilers when needed)
40 amp ESC from Cape Sailplanes
540 brushed motor - direct drive
2S1P 2,2 amp LiPo

Which direction do I set the ailerons to get added lift when in a thermal?

Geoff

Elfwreck
12-08-2005, 05:26 PM
Hey now,
You may not want to change the ailerons at all, some airfoils don't work anybetter with camber or reflex.
That said, to gain a little extra, if it helps at all, two or three degrees camber (aileron droop) would be the way. You may need a click or two of down elevator to comensate for any pitch changes that go with it.

Now your prolly better off just adding some up elevator (a few clicks) when you enter thermals. Most motor sailers are set up for powered flight and that leaves them a bit nose down for gliding. They have to comensate for the lift added by the extra speed...
good luck.
RobII

Geoff_Gino
12-09-2005, 05:49 AM
Hi Rob

Thanks for the info. I would like to try the droop or I suppose properly termed "flaps" and my intention was to go for a max of 3 degrees.

Thanks
Geoff

Elfwreck
12-09-2005, 05:06 PM
Hey Geoff,
The propper term for the droop is "camber", if you were to raise them it would be called "reflex". "Flaps" are a seperate control surface all together. Some gliders have four servos in the wings, two on each side.
And what would be the ailerons are cut to half their length, the outside half is the aileron and the inside half is the flap.

If you have the four servo wing you can do many more nifty things like; "snap flaps" where the flaps move opposite to the elevator. This allows you to turn much tighter without losing as much speed.

"crow" where the ailerons go up a few degrees increasing washout, and the flaps drop ninty degrees as airbrakes, and the elevator adds a little down to keep the model from ballooning up. You can slow the model down to about four mph and do very presise spot landings this way.

You can also vary the "camber" and "reflex" so you don't get as much change on the out board section, helps keep it stable.

Sorry, I do run on sometimes... Anyway, yeah try to camber about three degrees, but also try adding a tiny bit of up elevator after motor shutdown, that could make the most difference.
RobII

kepople
12-09-2005, 08:12 PM
If ailerons do not go full span, camber will do very little for you. If they do, 2 degrees may help. Keep in mind that some sailplane wings have camber already built in.

Kirby

Elfwreck
12-09-2005, 08:56 PM
Hey now,
Well I get a dope slap for foregetting that one don't I?
Oh well...
Still I get the feeling that the basic trouble is the Geoff isn't getting the lift from thermals he's expecting. So cambering the wing is prolly a secondary issue. Most (all?) motor sailers are set up for powered flight.
If everything is trimmed so that it flies level power on it's going to have the nose too far down for good s*l*o*w thermal flight. Either adding some "up" trim, *or* rebalancing it so it glides well but needs down trim (one of the common "mixes" in most computor radios) for powered flight. would be the first thing to try. With my competition thermal ships I don't often use camber in thermals unless I'm really scratching for lift and I don't see a lot of the other guys using it much either.
RobII

Geoff_Gino
12-12-2005, 06:32 AM
If ailerons do not go full span, camber will do very little for you. If they do, 2 degrees may help. Keep in mind that some sailplane wings have camber already built in.

Kirby

Hi Kirby and Rob

Thanks for both your answers. First the good news, went out Saturday and with no-one else in sight (maybe a good thing :o ) put my heart in my mouth and being mode 1, opened the throttle with my mouth (heart got in the way :D ) and threw. WOW :eek: it went up at a gentle angle, straight and true with very little input, did a few ccts and WOW :D landed without breaking it.

This made me so brave I "threw" it again a had a repeat performance :D .

Rob you say you go on a bit - don't get me started (as you can see from the above ramblings) but I was really excited. Now the bad bit - somebody PLEASE teach me to fly this beautiful bird as I find it very different. I do have a computer radio so I'll be using your mixes as suggested and what you have both said makes sense - when I cut power I am only using a little up elevator and wiil put that mix in. Found that the rudder was very ineffective and had to turn with ailerons which are very, very sensitive (guess I'll have to go for dual rates seeing as I don't favour Exponential.)

I will appreciate any input from you guys and if you like PM me so as not to clutter up this forum.

Thanks for the advice and looking forward to more.
Geoff

Sky Sharkster
12-12-2005, 01:34 PM
Hi Goeff, welcome to the wonderful (and frustrating) world of E-Powered gliders!
It sounds like you've gotten some pretty good info so far. I have a couple more suggestions;
Instead of trimming "up" for the glide, if your TX permits it, have a "power" trim. Couple the throttle to a bit (maybe 2 clicks) of "down" elevator, a bit of "right" rudder to counteract torque and after you get used to flying the ship, a click of reflex-up spoilers-this last doesn't always help, it depends on the airfoil and climb speed. Now your "default" or netural trim will be "Glide", that is, when you close the throttle you'll be in glide trim.
Second, you may want two glide trims. A slow, almost to the stall point "thermal" glide mode (pretty easy to trim in) and a "cruise" trim, this would be about 1-2 clicks of "down" and perhaps 1 click of spoiler reflex ("up" spoiler) to allow the model to cover airspace quickly, get out of downdrafts, return back upwind, search for lift, etc.
After these you can program "crow" or "landing approach" modes, flaps, etc. in a way that makes sense to you on your TX. I also fly Mode 1 (lefty) or mode 3, so I put the "cruise" mode on left-hand upper switch for my thumb, "landing" on the right-hand thumb switch so it's near the throttle. If you have to go around again it's handy to have the "of/on landing" switch near the power control.
Anyway, good luck and find some thermals! Ron

Geoff_Gino
12-12-2005, 01:49 PM
Hi Ron

Have printed all the instructions and the only BAD thing is - I have to wait for Saturday to try these tricks. They all make a lot of sense and to start I think I'll go with "glide" mode being level flight with no power applied and climb out with 2 or 3 clicks of up. I have a JR2610 (your JR6210) and will be able to mix those in with the mix modes.

Shall read the manual tonight and get it set up for Saturday, and also the spoiler up for the go around. Noticed I was landing deep and now I know why.

Thanks
Geoff

Elfwreck
12-12-2005, 06:20 PM
Hey Geoff,
"cluttering up the list" is exactly why we're here. The thread isn't just for you, as much as it is about that, it's also for the other guys that may be having the same troubles but don't want to ask directly.
So let's just keep it here.
Ron said some good things about this too, some paralleled what I said, 'though it may have been buried in my posts. Setting up different "flight modes" is very helpful, my "pure" gliders all have several "flight modes"; launch (flaps down four degrees, ailerons slightly up for stability, and a touch of up elevator), thermal (that hanging at the edge of stall thing), speed (to get out of sink fast! Nose down, slight reflex), and landing (I use "crow" flaps down, ailerons up and elevator slightly down).

You can't do "crow" per se, having only ailerons, but you could raise the ailerons for landings i.e. "spoilerons", raise them about thirty degrees and *maybe* add a couple of degrees down elevator, try it high first and see how the model reacts, some will "balloon" that is, jump up quite a bit, others will dive fast so you'll need to check which your model does to know how much elevator to add, and in which direction.

Um, for help learning to fly the thing well. I'd be happy to teach you in person, but you'd have to come to the San Fransisco Ca. USA area, cause I'm not getting to africa anytime soon, too bad for me, I really enjoyed my time there...
RobII

Geoff_Gino
12-13-2005, 05:44 AM
Hi Rob

Yeah thought about the PM thing and you are quite right, why keep it to myself :o . I like what everyone has said and will definitely start off with 1 glide mode i.e. trimmed for 0% throttle with level flight and a gentle climb with 80% throttle. That way I figure on climb out at 100% throttle I won't have to worry to much with the elevator and can concentrate on keeping the wing level and getting into my first turn.

I'll introduce "spoilerons" for landings and thanks for the heads up on the 30%, I would have gone for less which might have landed me in trouble. As for getting out of a thermal, I'll have to take my chances at first as for the moment I wouldn't know one if I fell over it. :eek:

Can't wait for Friday as we have a holiday and so far the long distance forecast is for good weather. :)

Thanks again
Geoff

Elfwreck
12-13-2005, 04:01 PM
Hey Geoff,
Just remember to check the spoilerons at altitude first, if the setting is off a bit and you try them too low there'll be no second chance:eek:
Thermals will be easy to spot, at least the big ones. Your model will start going up (and up, and up...) just circle towards the wingtip that raises to "core" the thermal. To get out of one that's too big to just turn out of, or if you just get too high, just chop the throttle (of course it should be off anyway at this point) and peg the elevator and rudder (hard up and right works for me) and the glider will stall and tumble down slow enough that you won't exceed maximum speed. Other wise just diving out could rip your wings off (ouch!). Good luck.
RobII

TeslaWinger
12-16-2005, 06:34 PM
Congratulation, Geoff!

You have chosen a complex aircraft to start with but the payoff is in flexibility and capability. Every question you ask is read by a hundred guys with the same questions who didnt quite understand the problem enough to ask.

You will never see the sky in the same way again. A parking lot upwind will be baking in the sun and releasing lift, deflected upward by a hillside and treeline, making friends with vultures, poring over soaring literature- all of which is directly relevant, whether about fullsize sailplanes, hang gliders or soaring birds, all using the ultimate use of solar energy- thermal soaring! The very sight of a sky full of fluffy cumulus clouds will raise your spirits and beckon you with the promise of lift. A dustdevil will cause you to pull alongside the road and gawk. All these technical terms and glider configs will become second nature and your intuition and observation will bring you an apreciation and understanding of things most people never even notice. Welcome.
TW

PS- As for your mouth throttle technique and heartrate- it reminds me of my knees shaking every time I flew at first- it was hard to stand at times on those first few outings.

Geoff_Gino
12-19-2005, 11:04 AM
Hi TeslaWinger

Your statements are entirely true. Had a holiday Friday and as luck would have it my Instructor was at the club. Had a long discussion about the various set ups and settled for 3 to start with.

Power (or climb out) mode with just enough up elevator to not have to worry about the elevator after launch and a glide mode with enough elevator to keep level flight with the throttle off. Assigned the lower right switch on my JR radio for this and it worked a treat.

Also introduced "spoilers" with up elevator when deployed and in my instructor's (Chris) expert hands landings looked pretty easy and with no more deep landings.

Had to do more than a couple of launches to get the settings we needed.
Once set up Chris found a thermal pretty quickly and was a little despondent when I asked "may I fly for a while".

All that is needed now is to get the dual rate settings for smooth flight, find that I am bit jerky with full rate.

Must admit that even though I wasn't flying it was an awesome sight to see the "bird" rising with little or no input from the radio.

Looking forward to my solo flights after the Christmas week end.

Geoff

TeslaWinger
12-19-2005, 01:30 PM
Congratulations, Geoff!

I think of it as like playing a musical instrument- ya gotta practice! Sure it is a technical device with many physical considerations but at some point in your progress it suddenly all sinks in and you find music pouring from within you without regard to all the technical challenges that at first seemed so daunting.

You are well on your way, my friend. Make a conscious effort to relax your hands and mind- I use a strap to support the TX, which helps- and the smoothness will come naturally. The more subtle your control inputs, the better it will fly.

Give some thought and study to the speeds- Minimum Sink Speed- and Best Glide and their use, as well as everything you can find on thermal theory and soaring and learn to see what cannot be seen- soaring intuition.

Many safe and inspiring flights,
TW

Geoff_Gino
12-19-2005, 01:47 PM
Congratulations, Geoff!

I think of it as like playing a musical instrument- ya gotta practice! TW

Thanks TW

Yeah practice there will be - and lots of it, only been flying since April and I know that "stick time" is the only way.

Cheers
Geoff