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Aug 22, 2009, 01:06 AM
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Soaring on Sunday

Is anyone going to be at the sod farm on Sunday with a winch? I may be able to make it up on Sunday to do some flying.

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Aug 22, 2009, 06:22 AM
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I'll be at the sod farm on Sunday with a winch; arrival time will be between 12:30 and 1:00. I hope you can make it.
Bob J.
Aug 31, 2009, 11:44 AM
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Scott and I and The Bruce

Hi All,

Scott and I got back from The Bruce handlaunch contest in KY last night, and it was a good time.

The results are located at The Bruce F3K .

The field was very different from anything we have flown off of before. The field boundaries were smaller and square. Also, the field was surrounded by trees except one end with a plane eating ravine. It was fun to try an event at such a different venue. The lift was sporadic and small across the field due to the tree lines, but you could work the trees for some 'slope' lift. It seemed to me that the best way to find lift was to launch and head out over the trees and work along the tree line until something came along. Although it is common in most contest to see the best pilots head downwind immediately, a lot of them went upwind or to the side due to the different conditions.

The conditions were cool (by Kentucky standards) and calm. I didn't have to pull out the ballast the entire weekend.

If you look at the results, don't be fooled by Scott's placing. He had as much bad luck as a guy could have with his planes. He had to fight with plane problems the entire contest. Considering what he was up against, his placing is quite good. As usual, Scott was his classy self and didn't yell or complain and made the best of it.

I feel satisfied with my results, but I still have a lot to work on. Knowing when to play it safe and knowing when to go for it is a big part of contest flying, and I don't have a good feel for that.

I saw a lot of cool planes at this contest including The Zone from Gerald Taylor (flown by Gerald and Phil Barnes), and some Euro moldies like the Salonit and the Salpeter. More and more people are migrating to the molded DLGs with full fuselages since they are very stiff, so they 'seem' to launch better (among other reasons). I have no personal experience, so I can't say for sure.

It was fun watching people trying to get back to the field boundaries after following lift downwind, since they had to get back across the ravines, and that was VERY turbulent sinky air. They were some that did some great flying at got back, but there were a lot of guys landing short off field (myself included on Saturday).

Overall, worth the trip. Heck, this is a local contest for us, only 8 to 9 hours away.

Ryan Thompson
Sep 18, 2009, 07:43 AM
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Lee's Constellation in the Air Again

Scott and Ryan shuffled the large XC ship to Gordy Stahl a few weeks ago.

Gory wasted no time in modifying it and getting the CG back where it should have been. Here is a video his friend shot.

Sep 22, 2009, 01:35 PM
Scott Zastoupil
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I'll have to watch it when I get home. Did Gordy try a cross country attempt?

We also saw your old "big wing" in Gordy's garage.
Apr 05, 2010, 01:10 AM
Scott Zastoupil
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Some of you may recognize the guys in this thread. A few local guys did their LSF 5, 8 hour slope flight in Platteville this past weekend.
Apr 08, 2010, 12:25 AM
Scott Zastoupil
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Well it was time to step it up a notch. I thought that I'd share my latest project that is finally paying off. A couple of weeks ago the CNC foamcutter project was finally finished and recently made the transition from making packing peanuts to a set of 4 Taboo GT discus launch glider cores. I took some video and plan to take some more and compile it for Youtube to share what it takes on making the machine and a sample of what it can do. Even though it wasn't too complicated in terms of parts, it required attention to detail to get the hardware store components to work in harmony.

As input, I enter the dimensions of the wing planform so it can calculate the tapers and proper speeds at the tip and root along with the airfoil coordinate files for the tip and root.

What is so awesome about the setup is that I've been measuring the final cores within 0.005" (thickness of a regular sheet of paper) of the intended airfoil thickness. The hotwire cutter has a kerf anywhere from 0.040" to 0.070" and cuts by radiant heat not physically touching the foam. It took a lot of calibration cuts at different speeds and measured wire current to develop the kerf relationship. With the cal data entered, the software knows how thick the kerf will be and compensates so you get what you want. The thickest part of the airfoil at the tip of the tip panel I'm holding is 0.140". These highly tapered cores are the most challenging.

Anyway, here's some photos of the operation. A couple of soaring guys helped me through email correspondence and was told it would take about one 4 x 8ft sheet of foam to get it down. I didn't believe them at first, but I ended up eating close to a sheet. The wood platform between the towers is a hollow perforated box used a vacuum chuck hold down with finished cores on the table. The second photo is pure bliss for me. That little indent is intended and not an imperfection. It's a kink in the airfoil meant for full wing cambering for speed, cruise, and launch modes. As is, the wing tip is in reflex. The back 0.25" of the trailing edge gets cut off.

I'm glad I did it. It was a lot of work and is taking a lot of practice. It's probably a wash in terms of time to cut compared to a manual gravity arm cutter, but the reproducibility is spot on. Speeding up the stepper motors will be a future modification...I hope.
Last edited by szastoupil; Apr 08, 2010 at 01:00 AM.
Apr 08, 2010, 03:21 PM
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Great work Scott. So when are you taking orders? LOL I mean all that time and effort needs a return..right? Do we get a discount for being local guys who bring beer when we pick up our parts?

Apr 14, 2010, 01:50 PM
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I'm disappointed about my Radian going down today and wanted to compare notes with the rest of the VAM fleet of Radians. The model was up about 1,000 feet and about 1/4" out. I had it this far away before. The model went into a dive and it made no difference if I used full up or full down. Nothing seemed to alter the vertical dive.

The TRX was using dry batteries and the middle green light was lit. I had used the TRX batteries about 3.5 hours. The TRX pack voltage was 5.6 Volts. The lithium pack was 11.5 volts. The radio worked when I got to the crash site. On the first flight I had a few seconds when it did the same thing but it recovered in a few seconds.

What do you guys think happened? Did this happen to anyone else?

Apr 14, 2010, 01:56 PM
Scott Zastoupil
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Which transmitter and receiver are you using? I don't have any first hand experience with spread spectrum stuff, but the "recovering" you mentioned sounds like a wait time for binding the TX/RX to occur.
Apr 14, 2010, 02:01 PM
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I didn't mention this was the DX 7e Transmitter that comes with the plug and play model.
Apr 14, 2010, 02:04 PM
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The receiver is the one which comes with it - the AR500. Thanks for the quick response, Scott.

Apr 14, 2010, 03:36 PM
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I've had my Radian spec'd out a couple of times but don't know the exact height as I don't have a real good feel for that. I've never had any issues with my Spektrum stuff although I fly it only in a parkflyer and the Radian.

I do know that I haven't flown the lipo down very far nor the Tx battery. You probably know that there are multiple threads where people are complaining about losing planes on Spektrum receivers. The one I've been following is in the Handlaunch forum and involves the AR6250 Rx specifically.

From what I've read, it seems like people get "holds" that are noted by a flashing red light on the receiver. That's not a case where the rx and tx have to rebind. If it occurs at a high enough altitude, sometimes the rx reaquires the signal. At low altitude, the plane almost always goes in. Being at 1000 feet, I would have thought that would be plenty of time to reestablish the signal.

That's a drag, Lee. There seems to be some weird stuff happening with the Spektrum stuff.
Apr 14, 2010, 04:45 PM
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I assume the 5.6 volts was no load voltage? Were the dry cells alkaline? Some of the non alkaline cells have poor current output capability and when the servo needs a slug of current the voltage can drop significantly for a short time (think mS time scale) which may be long enough to trip the brown out detection and reset the Rx.

Apr 14, 2010, 09:47 PM
Sorry to hear about your Radian, Lee. I think Jason may be on to something. I purchased the plug and play version of the Radian and added the AR500 receiver, 1350 mAh 3 cell li-po battery and a DX7 transmitter which has a 1500 mAh 8 cell rechargeable NMHd battery which generally runs at around 10.5 volts at the field and flew it a lot last summer and have never experienced any brown outs.

Sunday, I was flying the Radian which I just programmed into a JR 9503 transmitter with a similar battery in thermals to the limit of visibility with no problems.

I believe that if there was an onboard problem with your plane it would have gone into a failsafe condition of low throttle with no signal going to the servos and putting them in a neutral position. Your plane may have flown away in a thermal but it shouldn't have gone into a dive.

If the transmitter failed because of Jason's suggestion about the weak batteries then it is possible that the dive could have occurred.

It would be interesting to know if your plane could pass a ground check with the current transmitter batteries.

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