gavoss
Nov 27, 2002, 01:00 AM
<blockquote>Welcome to the newest column in the LiftZone online magazine, Thermal Talk. I'm your host, George Voss. It's customary in the first column to give some background information about the author, and this column will follow that tradition.</blockquote>
<p><big>In The Beginning</p></big>
<blockquote>I'm 43 years old and live in Oklahoma City. I've been modeling since I was nine and flying RC sailplanes since I was 13, which give me 33+ years in modeling. I grew up in a suburb of Los Angeles and started with FF (Free Flight) hand launch gliders. Within a year, I advanced to power. My best finishes were a sixth and a second place at the United States Free Flight Championships in 1975 and 1977 respectively. I was fortunate to have some excellent mentors, including Sal and Mike Taibi, Vic Cunningham Junior and Senior, "Red" Johnson, and Randy Secor. Each one of these men taught me a great deal about building, covering, trimming, and competing with FF models. They also taught me how to "pick" air. This knowledge directly transfers to RC (Radio Control) thermal soaring, and thermal soaring is the topic of this column.</blockquote>
<blockquote>My father had no interest in RC, so it appeared I was basically on my own. Fortunately for me, dad had a connection at work that flew RC. This gentleman, Jerry Brown, was willing to teach me how to fly. I purchased my first RC sailplane, a Dumas Evolution 2. The Evolution was a unique airplane since it could be built in a number of different configurations. It could be assembled as a power plane with either a high or a low wing, with landing gear or without, with a variety of spans, or it could be assembled as a sailplane. Since my funds were limited to a paper route salary, fuel was out of the question, so I built the sailplane version.</blockquote>
<blockquote>By today's standards, the Evolution wasn't much of a sailplane. Though I had the ability to build light, the wood in the kit was quite heavy. The airfoil wasn't the best for a sailplane or a power plane for that matter, but I was too inexperienced at the time to know any better. I had managed to save enough money to purchase a brand new Kraft three-channel "brick" radio, which was installed in the Evolution. The brick assembly contained two servos and a receiver in one unit. This made radio installation easy enough that even a 13 year old could do it. I actually did a fairly nice job finishing the Evolution, and Jerry was quite pleased with the finished sailplane.</blockquote>
<blockquote>My dad and I met Jerry one sunny Saturday morning at Cal Poly Pomona for my first soaring lesson. Jerry checked the Evolution for proper control movement and balance. He gave me the "thumbs up" and stated the Evolution was ready for flight. Needless to say, I anxious to see my creation, MY creation soar into the heavens. Jerry then recommended we fly his Ace Nomad first, so I could get comfortable using the transmitter.</blockquote>
<blockquote>The Nomad is a small 36" span single channel "cutie" produced in the 1970's by Ace. It was basically a FF model with a functioning rudder. This limits the operator to direction control only, while the plane basically flies itself. A Cox .020 engine mounted on a pylon provides the launch altitude. The radio, an Ace single channel pulse unit, allowed proportional rudder control via an actuator that pulses from side to side. The actuator has electro-magnets at each end and the radio intermittently applies voltage to these magnets. This causes the actuator arm to pulse from full left to full right. By changing the amount of energy applied to each magnet, via the control stick on the transmitter, you control the amount of rudder applied. The rudder is fully proportional so you could add small amounts of control and the aircraft responded accordingly. The interesting feature of this type of control is that the tail of the aircraft wiggles from side to side as it is flying. Even though you have proportional control, the actuator still flops from side to side, but more to one side or the other depending on the command by the transmitter. (In a future column, I'll have photos of a Nomad. Below is a photo of the Ace Pulse unit.)
</blockquote>
<blockquote>Jerry fueled the .020 with K&B 35% nitro fuel, started the engine, and let it fly. Once the engine quit, he handed me the transmitter and gave me instructions on how much and how long to input the control. For whatever reason, I was a natural. I managed to fly the entire flight, up to landing, without any difficulty. Jerry asked for the transmitter so he could make the landing. After the successful flight of the Nomad, he recommended we fly my Evolution.</blockquote>
<blockquote>Again, Jerry checked the control throws for proper amount and direction and we headed for the winch. Jerry hooked the Evolution to the high start and gave it a heave. As I remember, the Evolution launched straight and high. I was stoked! My creation had taken to the air and not only flew, but flew well. After launch, Jerry handed the transmitter to me, and though I didn't catch a thermal, I piloted the plane around the sky again until landing. I flew several more flights with the Evolution, and by the fourth flight, I was allowed to land. The next two flights proved to be both educational and frustrating.</blockquote>
<blockquote>The field was lined with several tall spruce trees, and I managed to clip one of them with the right wing of the Evolution. The impact put it into a flat spin, from which neither Jerry nor I could recover. Fortunately, the Evolution only suffered some torn MonoKote, but it was out of action for the day.</blockquote>
<blockquote>Jerry was pleased with my progress and suggested flying his Olympic 99. Unfortunately, during the launch, someone turned on a transmitter on the same frequency as the Olympic. The plane was near the apex of the launch when it abruptly rotated 180 degrees and sped to its demise into the hard ground. Jerry was furious and I was disappointed. However, I learned several valuable lessons from this first day of soaring. Depth perception is one of the keys to successfully sailplanes, and proper frequency control and conduct is imperative!</blockquote>
<blockquote>Later that year, I managed to hook up with a soaring club, The Silent Few Soaring Society, in Brea. My friends, Brad Litchfield and Pat Cronan, and I would ride our bicycles to the field on Saturday mornings and fly with the club. The club members always accepted us and allowed us to fly with them, without any pressure to join the club. On one Saturday, we arrived at the field to find that the club was having a contest. I told them that was fine, and we would just watch. The contest director however was having none of that. They asked if I was a member of AMA, and I was. I told them I had no money for the entry fee. One kind gentleman opened his wallet and produced a $5 bill, and handed it to the CD and said, "I'll pay his entry fee." I told them I wasn't a club member and another gentleman produced another $5 bill and said, "I'll pay his membership fee." Although I protested and told them I couldn't repay them, they welcomed me as a brother and fellow soaring pilot. I finished second that day, much to everyone's surprise. I flew in several other contests that year and almost always finished in the top five.</blockquote>
<blockquote>The reason I went into so much detail is that I had a tremendous amount of help when I started flying RC sailplanes. I haven't forgotten the assistance I received. I purposed in my heart that I would return the favor to other new comers. This column is one way to help me achieve that goal.</blockquote>
<p><big>What To Expect</p></big>
<blockquote>I feel privileged to have the thermal soaring column, since it includes electric, winch, aero tow and IC (internal combustion) power launch methods, along with slope, scale, hand, or discus launch and other flying disciplines. This certainly gives me many subjects about which to write. After accepting the column, I searched LiftZone for comments on what types of information you want covered. From your comments, I've determined you are interested in not only the high end of soaring and sailplanes, but grass roots, weekend warrior type information for the "average" flyer.</blockquote>
<blockquote>As a reader, I wholeheartedly agree with your wants, and as a columnist, I'll do my best to provide the information you desire. I'll include web addresses, print magazines, books, and other forms of reference materials so we can learn together. RC soaring is a great hobby. It's clean and quite, mentally challenging, physically stimulating (if you chase the winch or hi-start), and it's just plain fun!</blockquote>
<blockquote>Just before finishing this column, I've been notified that Marc Webster will head the new DLG (discus launch glider) column, which will kick off in another month or so. Until then, he will be imparting his wisdom and knowledge here in Thermal Talk. Our schedules aren't nailed in stone yet, but it looks like we'll have alternating articles. Personally, I think this is a great idea. Marc and I don't live in the same state and we have very different flying conditions to deal with. We also have slightly different interests as far as soaring goes, which means you get differing viewpoints from the writers. When we get our schedules worked out, we'll let you know.</blockquote>
<p><big>Next Issue</p></big>
<blockquote>In my next column, I'll show you how to transform the Great Plane's Spirit Elite ARF from a good sailplane into a great one! We'll put it on a diet and save close to one-half of a pound in weight, give it better handling without breaking the sailplane or your wallet. We'll make it easer to see, launch higher, and stay up longer.</blockquote>
<p><big>Closing</p></big>
<blockquote>I need your help making this column a success, so send your photos, questions, and comments to my email address at the beginning of this column. I'll do my best to get them in this column as quickly as possible.</blockquote>
<blockquote>Finally, I'd be remiss if I didn't say a hearty thank you to the one person who got me started building and flying model airplanes. So this column is dedicated to my dad, Ron Voss. Thanks dad for taking the time and energy to teach me how to build, covers, trim, and fly. I'll always treasure the times we spent together flying.</blockquote>
<p align="center"><a href="/articles/liftzone/2002/nov/thermal/pulseradio1.jpg"><img src="http://static.rcgroups.com/articles/liftzone/2002/nov/thermal/pulseradio1_t.jpg" border="2"></a></p>
<blockquote>Here is the entire Ace Pulse unit. Left to right, clock wise, we have the transmitter, a receiver, and a servo (actuator). A 9V battery powers the transmitter and two NiCad cells power the flight pack. This radio operates on the 27 MHz band, so it's more susceptible to interference than today's radios.</blockquote>
<p align="center"><a href="/articles/liftzone/2002/nov/thermal/pulseradio2.jpg"><img src="http://static.rcgroups.com/articles/liftzone/2002/nov/thermal/pulseradio2_t.jpg" border="2"></a></p>
<blockquote>This photo shows the actuator next to a modern day servo. The actuator is heavier than a micro servo, which would be considered a direct replacement. The actuator arm flops back and forth, which drive a pushrod to move the control surface. I'll have more info on how this unit works in my next month column.</blockquote>
<p><big>In The Beginning</p></big>
<blockquote>I'm 43 years old and live in Oklahoma City. I've been modeling since I was nine and flying RC sailplanes since I was 13, which give me 33+ years in modeling. I grew up in a suburb of Los Angeles and started with FF (Free Flight) hand launch gliders. Within a year, I advanced to power. My best finishes were a sixth and a second place at the United States Free Flight Championships in 1975 and 1977 respectively. I was fortunate to have some excellent mentors, including Sal and Mike Taibi, Vic Cunningham Junior and Senior, "Red" Johnson, and Randy Secor. Each one of these men taught me a great deal about building, covering, trimming, and competing with FF models. They also taught me how to "pick" air. This knowledge directly transfers to RC (Radio Control) thermal soaring, and thermal soaring is the topic of this column.</blockquote>
<blockquote>My father had no interest in RC, so it appeared I was basically on my own. Fortunately for me, dad had a connection at work that flew RC. This gentleman, Jerry Brown, was willing to teach me how to fly. I purchased my first RC sailplane, a Dumas Evolution 2. The Evolution was a unique airplane since it could be built in a number of different configurations. It could be assembled as a power plane with either a high or a low wing, with landing gear or without, with a variety of spans, or it could be assembled as a sailplane. Since my funds were limited to a paper route salary, fuel was out of the question, so I built the sailplane version.</blockquote>
<blockquote>By today's standards, the Evolution wasn't much of a sailplane. Though I had the ability to build light, the wood in the kit was quite heavy. The airfoil wasn't the best for a sailplane or a power plane for that matter, but I was too inexperienced at the time to know any better. I had managed to save enough money to purchase a brand new Kraft three-channel "brick" radio, which was installed in the Evolution. The brick assembly contained two servos and a receiver in one unit. This made radio installation easy enough that even a 13 year old could do it. I actually did a fairly nice job finishing the Evolution, and Jerry was quite pleased with the finished sailplane.</blockquote>
<blockquote>My dad and I met Jerry one sunny Saturday morning at Cal Poly Pomona for my first soaring lesson. Jerry checked the Evolution for proper control movement and balance. He gave me the "thumbs up" and stated the Evolution was ready for flight. Needless to say, I anxious to see my creation, MY creation soar into the heavens. Jerry then recommended we fly his Ace Nomad first, so I could get comfortable using the transmitter.</blockquote>
<blockquote>The Nomad is a small 36" span single channel "cutie" produced in the 1970's by Ace. It was basically a FF model with a functioning rudder. This limits the operator to direction control only, while the plane basically flies itself. A Cox .020 engine mounted on a pylon provides the launch altitude. The radio, an Ace single channel pulse unit, allowed proportional rudder control via an actuator that pulses from side to side. The actuator has electro-magnets at each end and the radio intermittently applies voltage to these magnets. This causes the actuator arm to pulse from full left to full right. By changing the amount of energy applied to each magnet, via the control stick on the transmitter, you control the amount of rudder applied. The rudder is fully proportional so you could add small amounts of control and the aircraft responded accordingly. The interesting feature of this type of control is that the tail of the aircraft wiggles from side to side as it is flying. Even though you have proportional control, the actuator still flops from side to side, but more to one side or the other depending on the command by the transmitter. (In a future column, I'll have photos of a Nomad. Below is a photo of the Ace Pulse unit.)
</blockquote>
<blockquote>Jerry fueled the .020 with K&B 35% nitro fuel, started the engine, and let it fly. Once the engine quit, he handed me the transmitter and gave me instructions on how much and how long to input the control. For whatever reason, I was a natural. I managed to fly the entire flight, up to landing, without any difficulty. Jerry asked for the transmitter so he could make the landing. After the successful flight of the Nomad, he recommended we fly my Evolution.</blockquote>
<blockquote>Again, Jerry checked the control throws for proper amount and direction and we headed for the winch. Jerry hooked the Evolution to the high start and gave it a heave. As I remember, the Evolution launched straight and high. I was stoked! My creation had taken to the air and not only flew, but flew well. After launch, Jerry handed the transmitter to me, and though I didn't catch a thermal, I piloted the plane around the sky again until landing. I flew several more flights with the Evolution, and by the fourth flight, I was allowed to land. The next two flights proved to be both educational and frustrating.</blockquote>
<blockquote>The field was lined with several tall spruce trees, and I managed to clip one of them with the right wing of the Evolution. The impact put it into a flat spin, from which neither Jerry nor I could recover. Fortunately, the Evolution only suffered some torn MonoKote, but it was out of action for the day.</blockquote>
<blockquote>Jerry was pleased with my progress and suggested flying his Olympic 99. Unfortunately, during the launch, someone turned on a transmitter on the same frequency as the Olympic. The plane was near the apex of the launch when it abruptly rotated 180 degrees and sped to its demise into the hard ground. Jerry was furious and I was disappointed. However, I learned several valuable lessons from this first day of soaring. Depth perception is one of the keys to successfully sailplanes, and proper frequency control and conduct is imperative!</blockquote>
<blockquote>Later that year, I managed to hook up with a soaring club, The Silent Few Soaring Society, in Brea. My friends, Brad Litchfield and Pat Cronan, and I would ride our bicycles to the field on Saturday mornings and fly with the club. The club members always accepted us and allowed us to fly with them, without any pressure to join the club. On one Saturday, we arrived at the field to find that the club was having a contest. I told them that was fine, and we would just watch. The contest director however was having none of that. They asked if I was a member of AMA, and I was. I told them I had no money for the entry fee. One kind gentleman opened his wallet and produced a $5 bill, and handed it to the CD and said, "I'll pay his entry fee." I told them I wasn't a club member and another gentleman produced another $5 bill and said, "I'll pay his membership fee." Although I protested and told them I couldn't repay them, they welcomed me as a brother and fellow soaring pilot. I finished second that day, much to everyone's surprise. I flew in several other contests that year and almost always finished in the top five.</blockquote>
<blockquote>The reason I went into so much detail is that I had a tremendous amount of help when I started flying RC sailplanes. I haven't forgotten the assistance I received. I purposed in my heart that I would return the favor to other new comers. This column is one way to help me achieve that goal.</blockquote>
<p><big>What To Expect</p></big>
<blockquote>I feel privileged to have the thermal soaring column, since it includes electric, winch, aero tow and IC (internal combustion) power launch methods, along with slope, scale, hand, or discus launch and other flying disciplines. This certainly gives me many subjects about which to write. After accepting the column, I searched LiftZone for comments on what types of information you want covered. From your comments, I've determined you are interested in not only the high end of soaring and sailplanes, but grass roots, weekend warrior type information for the "average" flyer.</blockquote>
<blockquote>As a reader, I wholeheartedly agree with your wants, and as a columnist, I'll do my best to provide the information you desire. I'll include web addresses, print magazines, books, and other forms of reference materials so we can learn together. RC soaring is a great hobby. It's clean and quite, mentally challenging, physically stimulating (if you chase the winch or hi-start), and it's just plain fun!</blockquote>
<blockquote>Just before finishing this column, I've been notified that Marc Webster will head the new DLG (discus launch glider) column, which will kick off in another month or so. Until then, he will be imparting his wisdom and knowledge here in Thermal Talk. Our schedules aren't nailed in stone yet, but it looks like we'll have alternating articles. Personally, I think this is a great idea. Marc and I don't live in the same state and we have very different flying conditions to deal with. We also have slightly different interests as far as soaring goes, which means you get differing viewpoints from the writers. When we get our schedules worked out, we'll let you know.</blockquote>
<p><big>Next Issue</p></big>
<blockquote>In my next column, I'll show you how to transform the Great Plane's Spirit Elite ARF from a good sailplane into a great one! We'll put it on a diet and save close to one-half of a pound in weight, give it better handling without breaking the sailplane or your wallet. We'll make it easer to see, launch higher, and stay up longer.</blockquote>
<p><big>Closing</p></big>
<blockquote>I need your help making this column a success, so send your photos, questions, and comments to my email address at the beginning of this column. I'll do my best to get them in this column as quickly as possible.</blockquote>
<blockquote>Finally, I'd be remiss if I didn't say a hearty thank you to the one person who got me started building and flying model airplanes. So this column is dedicated to my dad, Ron Voss. Thanks dad for taking the time and energy to teach me how to build, covers, trim, and fly. I'll always treasure the times we spent together flying.</blockquote>
<p align="center"><a href="/articles/liftzone/2002/nov/thermal/pulseradio1.jpg"><img src="http://static.rcgroups.com/articles/liftzone/2002/nov/thermal/pulseradio1_t.jpg" border="2"></a></p>
<blockquote>Here is the entire Ace Pulse unit. Left to right, clock wise, we have the transmitter, a receiver, and a servo (actuator). A 9V battery powers the transmitter and two NiCad cells power the flight pack. This radio operates on the 27 MHz band, so it's more susceptible to interference than today's radios.</blockquote>
<p align="center"><a href="/articles/liftzone/2002/nov/thermal/pulseradio2.jpg"><img src="http://static.rcgroups.com/articles/liftzone/2002/nov/thermal/pulseradio2_t.jpg" border="2"></a></p>
<blockquote>This photo shows the actuator next to a modern day servo. The actuator is heavier than a micro servo, which would be considered a direct replacement. The actuator arm flops back and forth, which drive a pushrod to move the control surface. I'll have more info on how this unit works in my next month column.</blockquote>