THERMALING 4 BEGINNERS--Help area - Page 13 - RC Groups
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May 29, 2004, 11:38 PM
FlattyFlier's Avatar
Balasting a plane has NOTHING to do with balancing it.

Balancing weight is used to set the CG. Adjusting the CG will not help you much in the wind. Get the plane properlly balanced for normal flight and leave it there. I was flying in 20 MPH winds and I did not move the CG at all. In fact I tried adding 1/4 ounce of nose weight to shift the CG forward a little. The plane did not fly as well.

What I did was add 3, then 4, then 4.5 oz of lead to a box I created right over the CG (right over the launch hooks). This does not change the CG of the plane, it just makes the plane heavier which will allow it to penetrate the wind better by gliding faster.

When you have the motor in your plane, it glides faster than when it is a pure sailplane. However the CG should be in the same spot.

hope that helped. Don't confuse balancing and CG with ballasting. They are different and have different purposes.
I never said it did, did I?
I know the CG has nothing to do with ballasting.
I was moving the CG from the aft position to the forward position for more/better pinitration, but it had no affect(I had balast in @ the time), so I just moved it back to the aft CG.
I dont need a box, i just velcro the battery(aka:tha' ballast) to the battery tray
It moves the CG back about 5mm from a CG thats in the middle rang of the CG spectrum. That gives me the aft CG recomended by the manuel.
My CG is always i nthe same spot. Motor or not...
The plane never wanted to speed up to glide. It stayed the same speed(down trim or not) as if the motor was on. Yes, it is about 5-10mph faster than w/o the motor, but the glide ratio shouldn't be as bad as it is compared to the glide ratio with the motor becasue is shoudl just speed up to get about the same ratio as without the motor. But it doesnt.(this has nothing to do with ballast...i tested this in no wind conditions)
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May 29, 2004, 11:45 PM
Proud member of LISF and ESL
OK, I miss understood your post.
May 30, 2004, 09:35 AM
FlattyFlier's Avatar
Thats just fine

No worrys.
Jun 02, 2004, 09:36 AM
FlattyFlier's Avatar
I have decided to make it a full time glider. The 6cell packs my LHS carrys just dont want to pull it anymore and its not realy worth the work even if i could find a 7s pack.
Should a make a nose block out of hard wood or soft? Should it be in the shape of a spinner or something else?
How big/long shoul dthe Nose Block be?
Thank you
Jun 02, 2004, 09:57 AM
Proud member of LISF and ESL
The Aspire and the Spirit are similar class planes with a fuse of about the same size. These photos of my crash damage showing the nose block separated from the fuse as well as the finished repairs may be helpful.

I would make it out of a modeling hardwood, perhaps basswood. Something you can buy as a block at the hobby store and sand/carve to shape. It is going to take some abuse, so balsa will be too soft and will deform too easily.

If you want to get creative you could make it out of some EPP type foam (not styrofoam) so that if you take a nose hit, the nose will absorb some of the shock. Attach it with screws or dowels so you can replace it easily.

Just a thought.

It should be rounded in some fashion to create a smooth air stream and avoid hard points that would be easily broken.

You also want to estimate its impact on balance. Too heavy and you will have to add weight to the tail.

When I fixed my spirit I embedded about 1 ounce of lead into the nose to help balance it. It puts it out farther from the CG making it more effective without adding more weight.

The other photos show my interior component arrangemetns, if that is of any help.

Hope these are helpful.
Jun 02, 2004, 10:12 AM
FlattyFlier's Avatar
Thanks a lot! That last pick realy helps.
My interior is basicly the same, but I have everything moved up about 1inch compared with yours becasue of me not having a weighted nose block.
Im hopein' to get started on it today, but I lost my GWS Corsair in some 4th tall weeds and have to find it first b4 the rain blows in overnight.
Jun 02, 2004, 10:46 AM
Proud member of LISF and ESL
Tell me about losing planes in tall grass. Our field is 800X1600 - Huge. The county has not cut it so far this year. Grass is 3-4 ft everywhere

I landed my 3M (10 foot) sailplane across the field. Turned to comment to someone and when I looked back I took the wrong spot to head for. 30 minutes later someone else found it 150 feet to my left. 10 FEET! I had just started to get more organized in my search pattern. The plane has a locator/beeper in it so when I turn the transmitter off it beeps, but the grass was muffleing it.

Good luck! Put a plane finder in your plane! I have them in ALL my planes!
Jun 02, 2004, 12:17 PM
FlattyFlier's Avatar
I found it, thanks
Took my lil' sister's 4-wheeler out and looked for about 15min. It was about 20yards down wind of where I had been looking this morning. It being a foamy, a bird or something had nibbled off a chunck of aileron But thats easly fixed
Jun 02, 2004, 11:37 PM
Proud member of LISF and ESL
This is what I use in my Spirit Sailplane and my Electrajet park flyer. It is
called a Digi-Alarm

It hooks to any channel or it can share a channel with one of your servos. It
has the connector to pass through to the servo. This will work in any plane
with a 72 MHZ receiver. I had a Hobbico Air Alert but I did not like it.

Low Voltage Watch

In addition to helping me find the plane, the Digi Alarm also monitors my
battery pack voltage and sounds an alarm if the pack voltage gets below a safe
level. This is especially valuable on my glider. If I catch a good thermal,
I could be in the air for over an hour, so a pack that tested good on the
ground could run low during the flight. The digi-alarm would warn me during
the flight.

Channel Conflict Test!

As a test to make sure no one is flying on my channel I turn on the receiver
only. If the device does not go into lost plane mode then someone else is on
my frequency. I may have just saved my plane, or someone else's.
Jun 03, 2004, 12:30 PM
FlattyFlier's Avatar
That sounds like a very handy devise
I'll try and look into it. Thanx.

Do you know anything about DLGs and HLGs?
I took my old SS and made a V-tailed DLG/HLG per manuel instructions and some pics from Matt Chester. (I can get you thoughs pix if you wan to see them.) His plane is VERY nice and flies well.
Mine does well, but I think the high undercambered airfoil decreases it's performace.
It does have a very good 10:1(drops 1 foot for every 10feet it glides-on av.)glide ratio. But I can only get Discus launches of only about 15ft. I tryed normal hand launching(strait out) but only got to 10foot before it stalled and came back down to about 4ft I also try high start launching it from a normal high start with about 20 or so feet of string and streched to about 15 paces. I had some TE wing flutter, but it didnt hurt it. But Thoughs weren't worth the effort.
How do I get higher launches? And how do I detect thermals if there is NO wind and NO bugs or birds. The only way I can get into a thermal with 15ft DLes is to launch strait into it and hope it takes me up before it breaks off.
The plane is very light(only heavyer than my GWS Pico- Tiger Moth) so it will go right up on light lift, but I have to find that lift first.
I tryed looking out just above the ground to see the heat rising, saw some, but it wasn't thermatic. Tryed feeling the wind, but no luck there.
Jun 03, 2004, 01:25 PM
Proud member of LISF and ESL
The slow stick might be a good hand launched glider for tossing around but I would doubt it would make a good discusss launch and don't think you are going to get it very high with a hi-start.

Use it with the motor as an e-glider, get it up there and turn the motor off. Lots of people thermal them, but because it is fairly small, you can't get it too high or you will lose sight of it.

I just published an article on launching sailplanes. You might find some good tips. There is also a link ot a video on how to do a discus launch.\

Find the article here:
Jun 03, 2004, 02:21 PM
FlattyFlier's Avatar
Kool. I'll read it.
As I said, the DLs are atleast 5-10ft higher and they dont stall NEAR as bad. I realy wish there was a decent slope around here, but not that I've found.
I dont need it to be an EP because I got my second SS up and running today. I just figured I woudl make something out of the old SS parts I had lying around. High start launches are good, but I get concernd about the wing flutter and it slowing it down. But I cant do highstarts in my field anymore. Too many THICK(!) weeds.
But I can test further when I goto my Band practices this sommer @ the school(im 1st solo trumpet this year! ) in the soccer fields.
Do you think covering the bottom of the wing would help?
Jun 03, 2004, 02:33 PM
FlattyFlier's Avatar
I read the 1st 2 pages, but the video, i coudlnt find. I clicked on the link, bot no vid. Oh well, I learned how to from Hobby-Lobby's DLG vids.
I think I will try a tow line with my lil' bro. Wish us luck
Jun 03, 2004, 03:16 PM
Proud member of LISF and ESL
IF the video didn't work, copy the link into your browser. I let them know there was a problem with the video.

The wing of the slow stick was made for, da!, slow flight. So a high speed hi-start launch is going to stress those wings. Covering the bottom to create a flat bottom airfoil would make a big difference. Try packing tape as a first attempt before you do something more permanent.

The field where I fly has grass 3 feet tall right now. I hi-start all the time! Should be cut this week, I hope!
Jun 03, 2004, 03:55 PM
FlattyFlier's Avatar
Ok. Will do

My field is VERY thick in big weeds. I bogged down my 4 wheeler in it looking for my Cors'! You can barly walk in it. Its not grass. It used to be a corn field, but not fo rthe past 3-4years. Too thick to high start.

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