THERMALING 4 BEGINNERS--Help area - Page 19 - RC Groups
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Jun 24, 2004, 10:43 AM
Think Thermals!!!!
SoCalGliderFlyr's Avatar
As the Aspire has a fixed horz stab and an elevator the incidence is set in the positions the wing and stab are mounted to the fuse. Thus you may not be able to move the balance point back as far as the aerodynamic platform will let you. Still the aerodynamics dictate how far the tow hook can be moved back. Between the two you have to find the sweat spot.

I use the designers/builders/flyers settings as a guide then push them to my liking. In many cases a half ounce of nose weight can make or break a balance.

I tend to design and built with full flying stabs as I don't like having the incidence restrained. Still the airfoil on the stab can be somewhat critical.
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Jun 24, 2004, 12:41 PM
FlattyFlier's Avatar
I think I have found my "sweat spot". Th ehook needs to be @ the forward CG of 3.5" when the CG is set to 3 3/4" back from the LE. That gives me the 1/4" distance infount of the CG of the hook that aeajr was talking about for his Spirit. I think this is the best spot for my Aspire, even in higher winds(witch I had to deal with today ).
Thanx anyway!
And thank you, aeajr, for your suggestion
Jun 29, 2004, 05:44 AM
Registered User

New to thermals..!

hey guys,
I live in a country called New Zealand where the range of RC products aint that great. However i would like to start thermal gliding!!!
I do have flying experience as i have been flying a slope soarer (epp) for about six months and i can manage it quite well. I live in a part of the country where it is quite hilly and i could only find an acre of flat ground where i think is suitable for thermal flying.
I would appreciated if some one could help me choose a suitable glider.
At the moment my options are quite restricted, ive been fishing around web sites of LHS and only to manged to find the following planes.

Bird of Time (probaly too big)
Daydream from dynaflite
butterfly from dynaflite
Piece o-cake also from dynaflite
The spirit series (from great models i think)
Im open to other sugestions as well!!
However i will try to hunt down some more planes that are on sale here. Because of the small size of the field (a little bigger than an acre) what type of histart or up-start i should use? I could make a "homemade" one if i was givin some instructions and list of materials that i might need.

Sorry for the long post, but any help would be greatly appreciated
Thanks guys....
Jun 29, 2004, 06:47 AM
Proud member of LISF and ESL

Welcome to RC flying. Glad you are doing so well with slope soaring. I have the opposite problem, I have a great thermal flying field here on Long Island, New York, but there is very little in the way of suitable slope sites. Here is a pictue of our flying field:
Long Island Silent Flyers Field

There are lots of good starter planes.

You mentioned the Spirit Series. I started with the Great Planes Spirit 2M and recommend it highly. In the US it is available as a kit, ARF or a ready to fly packge called the Spirit Select.

The Gentle Lady has a wonderful reputation as a starter plane and is available as a kit or an ARF.

Since you have been flying an EPP plane, you might check out the Gentle Foamy from mountain Toys. This is a kit, but because it is an EPP foam plane it is closer to an ARF in its construction, I believe.

These articles may be helpful.

Getting Started in Sailplanes

Learning to make and use a hi-start

Sailplanes are Wonderful

Also, chat with guys at the Cantebury Sailplanes Forum in NZ. I post there from time to time. They can give you local insights.
Jun 29, 2004, 07:14 AM
The Airplane Gremlin
Seared Ice's Avatar
As long as you have enough space to strech out a highstart, you've got yourself a thermal field! Even if there isn't enough space for that, you can modify your plane for electric power or even a .049 glow engine. I have a Gentle Lady glider and its great! I have the added weight of the electric setup in mine but boy does it still thermal well!

I've got the same problem as aeajr...plenty of large fields (This side of the US was at one time, 1000s of farms...) but no slope soaring hills. I've got plenty of hills in PA (foothills of the Poconos) but as the name of Pennsylvania suggests (Pennsylvania means Penn's Woods), they're all covered in trees! And like aeajr, I also post every now and then in the Canterbury Sailplanes forum...they are very very nice people with tons of info to share with you!

Jun 29, 2004, 07:50 AM
FlattyFlier's Avatar
Let me welsome you to my/our thread!
Im very glad you posted here, we'll help you everyway we know how!
So you have about 1 acher, that is too small for much of anything but a mini-up-start, witch you use with HLGs. Contrary to aeajr's suggestion for the spirit(witch is a GREAT plane!)im going to recomend a hand launched glider(HLG). You can get upto 100ft launches from a simple "Javilin thow" or you can use the mini up/high-start witch will give you the same, if not about 50ft more with minimal effort! An HLG or DLG woudl be a great choice for a small field! + there very fn and give you lots of exercise
From dynaflite I would tell you to go with teh Skeeter, but ONLY if your conftorble with wood/balsa kits!
If not, goto and search for GreatPlanes "Fling" HLG. Its a very good looking ARF witch also has a great price of 65 U.S. dollers! And the best part is that it comes with it's own mini up-start!! Just install you excisting radio gear(if its mini or micro servoe gear) and goto that field! You can use it as a HLG or with a slight mod it can become a decent DLG! This is a VERY nice plane and if you dont mind the violet color, prbably the best plane for you!
Let us know on your decition

What are the surroundings around the field and whats' the field look like?
Also, whats the weather like?
Last edited by FlattyFlier; Jun 29, 2004 at 09:46 AM.
Jun 29, 2004, 09:21 AM
Proud member of LISF and ESL
Jake makes an excellent suggestion in a hand launched glider or a discus launched glider. On a small field, these could be great.

Even at our large field, more and more of the pilots are starting to explore discus launched gliders or hand launched using mini-hi-starts. They are very light and will rise on the lightest lift.

The one that was at the field last week was about 1.3 meters, a full house 6 servo DLG that was under 12 ounces. Amazing and beautiful.

I don't know if the conditions are very windy in your area. These planes my not be very good in strong winds. Others may be able to comment

On the other hand, if you have an acre, which is 200 feet by 200 feet, depending on the actual shape and size of the field, you can use a strong up-start to get good launches.

Typically a 2M sailplane would be launched with 3/16 to 5/16 inch surgical tubing which you would stretch 2-4 times its length. You get 6-10 pounds of pull on one of these.

My practice upstart is based on 25 feet of 7/16" rubber, which is very strong so I don't pull it as far. I get about 13 pounds of pull at 40 feet of stretch. It gives a very strong launch to my 2 meter planes. I have 150 feet of line so I can use it in about 200 to 225 feet of space and get 150 to 200 foot launches with my 2M Spirit or Sagitta. I have launched 3M planes on 100 feet of line with success as well. It is described in the article posted above on learning to use a hi-start.

The smaller rubber gives a softer launch but you need more space. My planes handle the strong launch with the heavier rubber with no problems.

If the lift is reasonable, that is high enough to catch thermals even with a 2 meter plane.
Jun 30, 2004, 12:29 AM
Registered User
Wow thanks for all the reply guys!
I sorry to mislead you that the field is 1 acre but its actually 1 and hectare and a bit. its also a squarish field with surrounding trees and some buildings and only one side leads to another padock. Once my mate came down from auckland and did some thermaling and he caught one straight after he launched! However he is now out of the country and cant contact him regularly.
anyways the wind here is not that strong in summer but could be quite gusty in winter. Im still researching for a plane here nut im not neccacarly going to go with the dynaflite range, as i will also look into HLG more as well.

Thanks for all the help and support
Jun 30, 2004, 07:25 PM
FlattyFlier's Avatar
Don't mention it!
Thats what Lift Zone is here for, Help!
Im not fermilior with the metric system in mearusers over meters, so could you clarify what a Hectare(hehe, "and a bit" ) is, please?
He might have got lucky, but if there is a few houses with dark roofs on them you can get some lift(small lift, but strong enough for the small HLGs) off the roofs and maybe the streets. If I had the field all to my self, If I were you I would cut the grass as short as posible on about 1/2 of the field(the average upwind side) so that the grass dies and creats a big brown spot that is much darker than the rest of the field would be. That woudl give your great lift on even humid days, as long as its sunny.
Sounds like you have a good weather situation! Nice thermaling in the summer(thermal's peck time) and slopeing in the winter. Nice situation as long as you dont mind a lil' cold air
You can also look into !
They have very nice and easely built HLGs and DLGs that are VERY light on a wallet
They are also very nice and very trust worthy, but on a couple HLGs you woudl need to brace up the balsa ply tail feathers with a CA bath or some epoxy soaked CF strips on the leading edges for extra insurace. Ive herd nothing but great news from these models and I, myself, am getting the COLIBRI-V HLG or maybe the BOBOLINK 1M DLG! If these are available to you, I would jump on them, but only if the GreatPlanes "Fling" HLG isn't available to you. I would get the Fling, but I already have a up-start that I can use with it, so I dont need another specialy for it, so im going with the Art Hobby birds.
Continue searching around on Lift Zone, and posibly E-zone, and where ever else you need/ want to.
Also! Try Hoby-Lobby! They have good small type sailplanes and im pritty sure they can ship to you no prob.

Have fun with it!

Jul 01, 2004, 02:04 AM
Registered User
hey again,
One hectare is 100m by 100m by which is about 2.5 acres the "a bit" is around 100feet plus 100 feet extra...if u know what im saying . so intotal prbaly around 2.8 acres (if my maths is correct). Unfortunately the roof of the shearing shed is orange.
However im moving to auck at the end of the year so i probaly could join a club and have a lot more space to fly around so im going to stick to the spirit 2m. Unless some other suitable plane comes into my attention, but i still dont have all the money i need yet and im still saving up.....just a few more weeks (hard beeing a teenager....sigh).
but untill then i guess i just have to find some extra work but no body wants a 14 year old breaking the dishess, hehe...
Last edited by silentfly; Jul 01, 2004 at 02:17 AM.
Jul 01, 2004, 05:45 AM
Proud member of LISF and ESL
The Spirit is a great plane. You should enjoy it. If you have a three channel radio, the built in spoilers can really be helpful in landing the plane in smaller areas.

If you enjoy building kits, then the Spirit kit is a pretty easy build.

Prices will vary for you as compared to the US, but if you add up the cost of the kit, the covering and other things, the ARF costs about the same as building a kit. However if you end up breaking something then you will end up buying some covering. Also, having the plans and the punched out wood as templates for replacement parts can come in handy.

I started with the RTF version that comes all built with all the electronics installed.

Ask away, we are very happy to help!
Jul 01, 2004, 07:58 AM
The Airplane Gremlin
Seared Ice's Avatar teenagers have $ trouble...I'm 16 and looking for a job. In order to get all my planes flying, I'll need to get 8 servos, 2 receivers, 1 rx batterypack, 1 lipo pack, one .40 glow engine, one electric motor, and much more! Will come out to around $250. If I get a job, that will be about one week's salary so...I really want a job!

About thermals: they don't have to come from the same field you're flying in! Most will come from surrounding areas. The good ones have had some time to form and drift to you from somewhere upwind. Next time I see some good thermal clouds, I'll take a picture. I'm thinking about waiting for a really good thermalling day and take a picture every 30 minutes or hour to show how the sky changes throughout the day.

Jul 01, 2004, 10:25 AM
FlattyFlier's Avatar
Originally Posted by silentfly
hey again,
One hectare is 100m by 100m by which is about 2.5 acres the "a bit" is around 100feet plus 100 feet extra...if u know what im saying . so intotal prbaly around 2.8 acres (if my maths is correct). Unfortunately the roof of the shearing shed is orange.
However im moving to auck at the end of the year so i probaly could join a club and have a lot more space to fly around so im going to stick to the spirit 2m. Unless some other suitable plane comes into my attention, but i still dont have all the money i need yet and im still saving up.....just a few more weeks (hard beeing a teenager....sigh).
but untill then i guess i just have to find some extra work but no body wants a 14 year old breaking the dishess, hehe...
Im a teen too, Jason 16, like John I know how it feels to be broke most of the time, lol. I have plinty of money, but thats for my car insurance! lol, Makes me mad that I have $300+ and cant use a bit of it when all I need is a 10x8 prop, lmao. But life goes on
You will like the Spirit in a field of that size! Especialy with the spoilers! If you cant get many thermals out of your field or from surrounding areas(like me) you can get a big black tarp(as im looking into) about 150ft x150ft or to about 300x300ft. Then you will have one area in the field that you can get thermals off of ALL day as long as teh sun is out! You can practice circling in light lift and waiting for the thermal to build and practice cucling in the core sence you would have a much better adea of where it is! And countless things that coudl be practiced on sence you woudl know where the thermal is! Its a good deal if you ask me, but aeajr might say different.
I have a job, but only when they need me, lol. But its $200 a weekfor a full weeks work, but they havent called in about 1 1/2 weeks. I might have to start looking for another, lmao, but its all koo
As for what aeajr has suggested with the timplate from the kit, I would strongly suggest that! But if I were you I would go with the RTF so I wouldn't have to switch out electronics and change trims on a Tx(as I do with my park flyers). It gets to be a hastle, even though you get good @ it, lol. But yeah, I woudl go with the RTF so you coudl have 2 planes(atleast) right there ready to fly as soon as you feel the need
Have fun, what ever you do!! Because in the words of a great man: " 'Cause its tha thang ta' do!"
Jul 01, 2004, 10:32 AM
Proud member of LISF and ESL
If you check this link on 7/2 you will find an article there on searching for lift, both slope and thermal.

Finding lift

As far as stretching your dollars.

Have you have ever looked at e-bay?

You can get some great deals, IF you know what you are looking for and what things cost at the store or on the internet. For example, I just purchased 3 brand new Hitec micro 555 receivers for $35 each from a hobby store in Canada. $8 for shipping and insurance for all three. One for myself and two for guys in the club. That reciever sells for $60 at Tower hobbies.

Servos that are $30 at the local hobby store and $20 at servo city I have been buying for $15 new.

I picked up, used, for $55 shipped, a 4 channel Futaba radio, 4 ball bearing servos and an 8 channel receiver. I would not have gone that high for a used reciever but I will use the rest of it. All I really wanted was the receiver, but I will use the radio as a buddy box on my Futaba 9C, and I can always use extra servos. He says all is in good shape. So, if the radio is warn but working well, if one servo has to be thrown out and the receiver checks out good, I think I will be all set and have a good deal.

With used stuff you ALWAYS take a chance, but after a year and dozens of purchases I have only had one problem, and the guy admitted he had listed it incorrectly by mistake. We came to a comfortable agreement.

You have to watch what is being sold and put in your bids. You have to know how to bid and when to raise, but you learn after a while. New stuff I try to get at least 20-25% off of regular sources. Used I want to save 50%

If I make 5 purchases and one has to be thrown away, I am way ahead. And many people will accept postal money orders, so you don't have to have a charge card.

Just some thoughts on how to stretch your $$. New is ALWAYS better, but that doesn't mean that used is bad. A lot is being sold by people who tried the hobby and did not like it. Some is part of estates. A flyer passes away. these guys buy the whle shop for a low price and sell the stuff off on e-bay.

There are a lot of regular hobby stores that sell on e-bay, like the one that sold me the receivers. I purchased new servos from them last year based on an e-bay bid.
Last edited by aeajr; Jul 01, 2004 at 10:46 AM.
Jul 01, 2004, 10:43 AM
FlattyFlier's Avatar
I didnt see anything from that link on tha page Only the 2 articles of Miniature engines, and How to used a Hi-Start to launch sailplanes. Nothing on lift at all, am I missing something ?