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Old Oct 21, 2003, 06:26 PM
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Brian,

You are right, it can be challenging to get the plane level. Using the gradual method I covered above, I hoped that the slow build up of tension would help people get that part right, but I still go off level at times.

A second issue is that people let the hi-start pull the plane out of their hands. If there is a good breeze, this works, but if there is not, the plane stalls before it gets up to speed and will usually drop off to one side or the other.

Hopefully it reaches speed BEFORE it hits the gound. Is it possible that you are not giving the plane enough of a push/throw when you are launching and that it is stalling on you?
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Old Oct 21, 2003, 06:31 PM
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Going from hi-start to winch

While this thread is about hi-starts, winchs are the next logical progression. I have been trying to master a winch launch. I am part of a sailplane club and we have 4 winches. The club contests are all based on winch launches so I have to learn to do this if I am going to enter the contests.

Weeeeellllllllll, I had two sorta ok launches one day. So I was feeling that I had the hang of it. The next time I went out, I approached the winch with confidence. MISTAKE.

I don't think I threw the plane hard enough and it stalled before it got up to speed. Splat on the left wing.
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Old Oct 21, 2003, 06:32 PM
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This is the left wing, after I removed the covering. I think I can rebuild it, but it will take some work.
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Old Oct 21, 2003, 09:40 PM
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Quote:
Originally posted by aeajr
Is it possible that you are not giving the plane enough of a push/throw when you are launching and that it is stalling on you?
It's possible. I was having trouble holding on to the plane with the full tension of the hi-start pulling on it. Next time I go out I'll try stretching it a bit less. Maybe I'll get more altitude by keeping the tension low enough that I can throw the plane more effectively.
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Old Oct 21, 2003, 10:58 PM
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Brian,

You should stick to planes with wing loadings of under eight ounces per square foot and use mandrel formed rubber for the histart. The mandrel formed rubber will stretch more and store more energy with less tension than extruded surgical tubing. The combination of a good rubber and light wing loading will allow you to get full height launches with less tension and less strain throwing the model properly. Such a model will accelerate to flying speed quicker because its stalling speed will be lower. If the tow hook isn't too far back it won't veer on launch. You can get mandrel formed rubber from Aerofoam.

The model that starts to veer on launch should be given a touch of down elevator and the down held to get the plane out of a stall during launch.
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Old Oct 21, 2003, 11:29 PM
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Thanks for the tips Ollie. I'm going to try to live with my current plane and highstart until the winter "building season" arrives, which I suspect will be within the next month or so. I may have a lighter glider and/or better highstart next year. Having said that, I know at least part of the problem is my technique since I have had two really good straight launches out of ten so far.

I have been using down elevator along with rudder to get it under control when it veers off to the side. Definitely helps to prevent pop-offs during the high-g turn.
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Old Oct 22, 2003, 01:15 AM
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Ollie brings up one very good point. Your tow hook should be in the most forward hole. My spirit came from the factory with the hook in the middle hole. I had to open the front hole.

The more foreward position will give you excellent launches with the greatest stability. As you go further back, the launchs may get higher, but the launch gets less stable.

Frankly, with the hook all the way up front I am launching about as high as my hi-start will go and get a good zoom off the end.
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Old Oct 22, 2003, 08:09 AM
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My tow hook is in the middle hole as that is where it was when I got the plane (used). I will try moving it up front before flying it again.
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Old Oct 22, 2003, 09:28 AM
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You will find the front position much easier to control.
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Old Oct 23, 2003, 10:38 PM
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Quote:
Originally posted by BrianRickman
My tow hook is in the middle hole as that is where it was when I got the plane (used). I will try moving it up front before flying it again.
Have you had a chance to try the front setting? I am dying to hear your results.
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Old Oct 23, 2003, 10:50 PM
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Not yet. I'm going to try again this Saturday if the weather is decent. It snowed today .
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Old Oct 25, 2003, 06:24 PM
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Flew the Spirit again today. The forward towhook was a big help. Did two good winch launches, one with a more experienced pilot on the pedal, and one on my own. The winch really gets it high! I even caught a little lift. Didn't climb much, but I was able to stay up longer then usual. Later there was a mechanical problem with the winch so it was packed up and I used my hi-start for a while. Got in three nice launches with that as well. Then it happened...

On my fourth and final launch something went terribly wrong. I think maybe there was a strong gust of wind from the side, or maybe I just dumb-thumbed it, not really sure. Anyway, it got up about 15 feet and then fliped over so the nose was pointing down. I tried to save it but just couldn't turn it over fast enough. There was a loud bang and a shower of balsa wood. The wing was a total loss. The rubber bands cut through the center section, and the tips shattered. Amazingly enough, the fuse and tail look fine. Would not have believed that was possible with a balsa plane. I have not tested the radio gear yet, though I'm hoping it all survived as well.

I ordered a "Gentle Foamy" a couple days ago, just in case something like this was to happen, so I'll be back in the air again soon.

Maybe after I've flown the foamy for a while I'll build a new wing for the Spirit. Or maybe not. I only paid $35 for this one, and it came with two standard servos. I think I got $35 worth of value from it as I have found out that I really enjoy flying sailplanes.
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Old Oct 25, 2003, 06:40 PM
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Sorry to hear of your loss. I to smashed up my Spirit, but I did it on a bad winch launch.

How did you get a side gust. You are supposed to be launching into the wind!

One of the things I like about the hi-start is that I can move around as the wind moves. so, if it moves off to my right a little bit, I just walk left with the plane hooked up until the ribbon on my radio antena is straight.

Here are a few ideas.

I hope you gathered up everything at the field. I thought my wings were totaled as well. Two weeks later I put them on the table and stripped off the covering. They were no where near as bad as I thought. I am fixing them now

Watch e-bay for low priced spirit kits or ARF sailplanes.

This link goes to an ARF Cirrus which is almost a clone of a spirit. Currently it is going for $38. It will probably go final at abround $55.

http://cgi.ebay.com/ws/eBayISAPI.dll...gory=2563&rd=1

At tower Hobbies, a spirit kit $47, a wing set is $60 and a Spirit ARF is $95. A spirit RTF, including the radio, receiver and servos is $139 RTF. I got a kit on e-bay for $20+10 shipping. I am using the plans from that to help me fix the one I have been flying.

My launches off the hi-start are as high as the winch, so my only reason to go to the winch is to enter competitions where the winch is required.

Now, tell me more about this foamie. Can you hi-start launch it????
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Old Oct 25, 2003, 07:10 PM
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The wind was quite variable. All of my successful launches were into the wind. Guess I just wasn't paying enough attention on that last launch.

Here's a link to the home page for the foamy:
http://www.isthmusmodels.com/mtntoy/gentle.html
It's supposed to be OK to winch launch it.

My hi-start is a bungie type, so it only takes the plane 1/2 as high as the winch, but it's still plenty high enough for sport flying.

I saved the fuse, but left the wing parts in the trash. Just didn't seem like it would be worth the trouble to fix it. I'll keep an eye out for Spirit kits on e-bay for when I feel ready to rebuild it.
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Old Oct 26, 2003, 12:01 AM
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BrianRickman

You don't mention the size or length of the bungee elastic, but I know that a 5/16 Dynaflite heavy Duty hi-start with 100' of elastic and 350' of line gives a great launch to a two meter Spirit. It will will take the plane up very high with a gentle launch. www.towerhobbies.com $60

If you plan to move on to larger sailplanes some day, you might select the NE Sailplanes Standard hi-start. Mine has 1/2" rubber and will take a 3 meter plane up to full height. My Spirit goes up very agressively, nothing soft about the launch. Since I don't pull it back as far as I would on the Dynaflite, I don't need as much room. If there is a breeze I could probably add another 50-100 feet taking it to 500' of line + 100' of tubing.

Just some thoughts. If you are commited to and have full access to a winch, then you probably don't care about hi-start alternatives.
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