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My Model Flying History (1961)

1961: So far I had assembled my models on the kitchen table. In the meantime we had cleared our corrugated iron garage so that we could use it as a workshop. We didn’t have a car back then. The next project was the free flight model “Donald Duck” of class A1 from Graupner. Unfortunately, we had made a mistake during construction: The trailing edge strip of the wing was not raised at the front but laid flat on the building board (as we knew it from the “Little UHU”). Therefore, the airfoil was incorrect and the flight performance was correspondingly poor. The model already had curve control and a thermal brake. We coped well with that and made a lot of flights. A fuse was used to trigger the thermal brake.

Next, a larger free-flight model was needed. It was a “Geier” of class A2 (now F1A) published by the Robbe company. It promised to be a competitive contest model. There was no kit available, just a blueprint. So we built everything completely from raw material. The model had a two piece wing and we got to know a tongue and box attachment. This time the airfoil was built correctly and the flight performance was impressive. We gained a lot of experience with this model.

One day, while browsing the Vietzke model shop, I discovered the book “Funkfernsteuerung fuer den Modellbauer”. It was a translation by H. Bruss and Hans-A. Pfeil of the English title “Simple Radio-Control” by H. G. Hundleby. I absolutely had to read that. I literally soaked up the content and that was my first contact with radio technology. I still have this book and I still like to look inside. It’s very tattered now.

From time to time we went to Hamburg, the next big city, for shopping. On one of these occasions we also visited the large model making department of “Spielzeug Rasch”. That was of course not to be compared with the small shop in Elmshorn. Our eyes widened more and more when we saw the many model kits and radio control sets that were on display. However, everything was so expensive that we couldn’t afford it. After all, we bought a few copies of the “Modell” magazine that we found there. I read all of them from cover to cover and was thrilled by all the new information. I was able to persuade my parents to subscribe to this magazine.

At the end of the summer we visited a model air show at the Hartenholm airfield near Bad Segeberg. What impressed me most was a biplane called “Captain”, which was flown by radio control. The model performed wild capers in the sky and hardly ever flew straight. It only had a 1-channel system with a rubber powered escapement. Today I know that the pilot probably had problems calming the model down with the right commands. Only when the engine finally stopped the flight became straight and the landing succeeded rather smoothly.

Some model shops exhibited their products along the site. One of them was the Carl Leonhardt company from Bad Segeberg. I was particularly interested in the new 3-channel radio control system produced by Metz. It seemed to be comparable to the Graupner “Bellaphon” system that we knew from the magazines, but was much cheaper. We took some handouts and leaflets with us, to study them thoroughly at home. I still have them.

My father had worked overtime and saved some money. We therefore decided to order the Metz 3-channel system at the Vietzke model shop. After a few weeks it actually arrived and we were able to pick it up. Of course, it had to be officially registered with the Federal Post Office and a monthly fee of 10 DM had to be payed every year. I still have the certificate.

Now of course we needed a new model for it. Although it would have been more sensible to build another glider, it now had to be a model with an internal combustion engine. The “Satellite” model was particularly recommended for this purpose in the Graupner catalog. This was a replica of the American model “Live Wire” by Harold De Bolt. But the kit was very expensive. You could get the new “Piper Tri Pacer” for much less money, and it looked even nicer. So we decided on this model. We later realized that this was a mistake.

My father built the model almost alone because it was to complicated for me. Of course, only the “Taifun Hurrican” Diesel engine was considered as the drive. It had to be broken in first. Back then, you could run an engine in the garden without a silencer without being scolded by your neighbors. During the working days, my father took the compression lever with him so that his son would not be able to run the engine while he was away. He knew me!

Eventually, the “Piper” was ready to go and we made our first attempts on the grassfield near Wittenberger Strasse. However, we found that the “Piper” did not want to roll properly in the tall grass to gain enough speed for takeoff. We had, of course, attached the beautiful wheel pants. So we found a tarmaced field path nearby for our next trials. But the model always only rolled a few meters, broke out to the side and stuck in the high grass aside of the road. It didn’t want to take off.

We came to the conclusion that the engine was to weak. So we needed a bigger one. This time it should be a glow plug engine. The OS-MAX 15. Of course, new accessories were needed. A glow plug clamp, a starter battery and a different fuel. After breaking in, the engine was installed in the “Piper”. But the following attempts to start were just as unsuccessful as before. The model didn’t want to take off. We could have tried to start the model directly from our hands but didn’t dare to do this.

Out of desperation, we contacted my father’s colleague Gerd Mix again and met him in Kollmar at the Elbe. He was a very experienced model pilot and took a close look at our “Piper”. He found no serious flaws and thought the model should definitely fly. We should try to start it directly from our hands . Together we went to the beach and started the engine. Gerd Mix took the model and threw it firmly into the wind. The model stalled immediately, turned on her back and crashed into the ground. Almost everything was broken and looked beyond repair. We never found the reason for this failure. For us this was the end of the “Piper” experiment.

 

My Model Flying History (1960)

1960: In a Mickey Mouse issue I found the instructions for building a chuck glider including a blueprint of the plan and all the information for the  material required. When I showed the plan to my father, he didn’t really believe that I would be able to build the plane. However, he agreed with my mother that we should buy the material. There was a small model shop close to the harbor of Elmshorn. It was operated by a couple named Vietzke. He was a passionate hunter and mainly sold rifles. His wife took care of the model making department.

To our horror, we found that balsa wood was only sold in whole sheets measuring 100 by 10 cm. We had to buy three sheets in three different thicknesses. Plus a tube of UHU-Hart. All together, that made around 5 DM. A lot of money for us in those days! When my father came home in the evening he said: “Well, then start building! If it actually flies, I will buy you a larger model.” Of course that was a huge incentive for me.

I assembled the model according to the plan. But since I had no practice in gluing the parts together exactly, the end product looked rather crooked. Nevertheless, I made my first flight attempts in our garden and in the “Zeppelinplatz” grassland. The model never flew straight but made loops and rolls depending on how hard it was thrown. I thought that was okay and was thrilled.

Fortunately, I was able to transfer my enthusiasm to my parents. So, a few weeks later, we went back to the model shop and had a look at the kits that were available. Fortunately, Mrs. Vietzke advised us very well and recommended a small free flight model, called “Little UHU” from Graupner. We also bought the necessary accessories: trim lead, pore filler, dope, towline. The tissue paper was already included with the kit.

I assembled the model with the help of my father. Since my father was a painter by profession, the tissue covering and painting job was no problem and the result looked really nice. We needed a larger grassfield for the test flights. We found it between Weidenstrasse, Waldweg and Wittenberger Strasse. Today this field is also completely covered with single-family houses. Back then there was a lot of space and you could climb up the dam of Wittenberger Strasse to start the model from an elevated position. We did not use the full line length for the high start, but limited it to approx. 30 meters. The “UHU” had no automatic steering and always flew straight ahead. It had to be recovered from an adjacent hedge almost each time. In any case, we had a lot of fun and were very motivated to continue.

 

My Model Flying History (1959)

1959: Our family had moved to a new location in Elmshorn. The name of the street was Langenmoor. I glued together some plastic kits for small fighter planes (ME-109 etc.) produced by the Revell company. I could only let them fly in my imagination adding the engine noise with my mouth.

I also built kites out of hemp twine, paper and pine strips. A carpenter in Goethestrasse sawed these strips for little money. I was able to fly the kites on a grassland between Langenmoor and Danziger Straße. That was a lot of fun. Today, this field is completely covered with apartment buildings and is now called Zeppelinplatz.

 

My Model Flying History (1956)

1956: It all started when I became 6 years old. My father had a colleague, Gerd Mix from Kollmar at the Elbe river, who was an experienced  model flyer. So my dad asked him if he could build us a small flying model that I should be given as a birthday present. It was a rubber powered model of very light construction with tissue covering. We had it fly in the garden behind our house in the Goethestraße in Elmshorn. Since we did not get enough turns into the rubber, the flights were very short. But I was fascinated and became hooked.

 

My Riser V-Tail

Here I want to show you my version of the SIG-Riser model sailplane.

This year, the idea came up in our club, to organize a competition of the R.E.S. class. R.E.S. stands for “Rudder Elevator Spoiler”. This class for simple 2-meter model sailplanes has become extremely popular in Germany. As I wanted to participate in this contest, I had to build an appropriate model. My choice was the “Riser” offered by the SIG company. One reasson for this was the extremely low price for the kit.

The building instruction was straight foreward, so I put the plane together in very short time. When it was time to build the vertical and horizontal stabilizers, I decided to make a change. I was convinced that the normal cross tail would be to heavy. So I changed it to a V-tail. I set the opening angle between the two sides to 120 degrees and  extended their length by 15 percent to get enough area in the vertical projection. I hoped that nevertheless enough controllability was given. The maiden flight should show it.

The plans for the model included an extra sheet for the installation of spoilers. Unfortunately, the material for this was not included in the kit. As I wanted to use two separate servos for the two wing sides, I had to think about a different way how to control the spoilers. Now they are hinged at the front edge with plastic tape and pushed up directly by the servo horns. Small magnets hold them down in the retracted position.

I covered the wing and the tail feathers with transparent OraLight. White on the top and red and blue on the bottom. The fuselage was just painted with clear lacquer. Despite of the lighter tail, a lot of ballast was still needed in the nose of the model to put the center of gravity in the right position. I decided to use a 2-cell LiPo of 2000 mAh combined with a UBEC-device. Now, the total flight weight came out at 630 g (~22 oz). So, this model seems to be more suitable for stronger winds.

For the high start a special rubber is required, which is extended with a fishing line. For this I made a wooden drum from a kit which was provided by Modellbau Claus Thiele.

Varioprop Conversion

Here I want to show you, how I converted an old Graupner Varioprop transmitter to 2.4 GHz.

I didn’t want to have another transmitter with all kinds of bells and whistles. My intention was, to make an old transmitter usable again that was laying around in my cupboard. I have other radios that can do everything. On the other hand, I wanted to improve my programming skills for the Arduino microcontrollers.

As I wanted to use this transmitter especially for my new SFC-Stick, I limited the number of controls to four (throttle, rudder, elevator, ailerons). The two extra potentiometers in the center were not yet connected to the controller and the 3-position switch was not used in the program.

First, I removed all the electronic components, the antenna socket and the battery until only the mechanical parts (sticks) remained. Then an RF Module from FrSky (V8HT) was inserted. The new antenna socket was glued in with epoxy. Also, a new charging socket and a new on-off-switch were necessary. The battery is a 2-cell LiPo of 800 mAh which is absolutely sufficient. The transmitter now has a very low weight (670g ~23.6 oz).

 

The PPM signal is provided by an Arduino Pro Mini.

You can find my sketch here: rc_encoder_sfc_stick

There is no display or keypad in the transmitter. If I want to change the program, I have to connect the Arduino to my PC and upload a modified sketch.

I use this transmitter specifically for my SFC-Stick model, which I have presented in another post.

 

My SFC-Stick

Here I want to show you my version of the Ugly Stick (SFC stands for Sport Flying Club). It was designed by a fellow club member more than twenty years ago as a project for our youth group. He provided some drawings the wing ribs and fuselage frames as milled parts and a stack of balsa wood for the remaining components. At that time, I obtained such a stack of material but never found the time to build the model.

Last year a new competition was devised in our club. We called it the “Fun Cup”. The rules: Within four minutes, as many rounds as possible had to be flown around two turnstiles 40 meters (~131′) apart. Within each round a “touch and go” had to be done in a landing field of 10 meters (~33′) in length. You got additional points for the final landing.

I really wanted to take part in this competition. But until that time, I had only flown gliders and did not have a single model with landing gear. What could I do? In February this year I discovered the material for the Stick in my cellar and started building immediately.

Originally, the wingspan should be 140 cm (~55″), but I decided to reduce it to 112 cm (~44″). The total length of the fuselage is also 112 cm. The wing was covered with transparent OraLight, white on the top and red on the bottom. The fuselage and the tail feathers were just painted with clear lacquer. The model is powered by an electric motor (DYMOND GTX-3546 (910kV)) and a LiPo battery (3s1p, 3300 mAh). The prop size is 11×7. The total flying weight is 1400 g (~50 oz).

 

The model flew very well. Since I had little time to train the “touch and go” part, my participation in the competition was not so successful. But most importantly, the model is still intact!

The following picture shows me holding the model after the end of the competition.

The model is controlled by an old Varioprop transmitter that I converted to 2.4 GHz.

 

My Chuck Gliders

At the age of ten I found the plan for a small chuck glider in a Mickey Mouse magazine. I asked my mother if she would buy me the necessary balsa wood. She did and my father promised to buy me a kit for a larger model, if I managed to finish the chuckie and bring it to fly. He did not seem very convinced.

The instructions in the magazine were quite detailed and although I did not build the plane very well, it eventually flew.

The model shown in the picture is a new one that was built when I led the youth group of the club. Wingspan: 380mm (15″), weight: 43g (1½ oz).

The next glider is a little bigger but lighter. Wingspan: 475mm (18¾”) weight: 36g (1¼ oz). It was made as a study model for a bigger RC version that I want to build.

Also as a study model for a bigger RC version I built a tailless chuckie. Wingspan: 500mm (20″), weight: 21g (¾ oz).

All of my chuckies are a little damaged from the test flights in my garden.

My School Project

In the last year of my junior high school I had to prepare a final year project. The subject was free. So I decided to build an RC sailplane and write about it. At that time, at the age of 15,  I had only built models from kits. But now I wanted to design this one on my own. As I had read a lot of articles written by Werner Thies and Karl-Heinz Denzin in the German “Mechanikus” and “modell” magazines, I had pretty clear ideas about the size and the shape of the model. The picture shows me holding the finished product.

I’m sorry that I can’t show a drawing of this plane, but it was lost. Also the model doesn’t exist any more. So I can only describe it from memory:

Wingspan: 1800mm (~71″)
Root chord: 200mm (~8″)
Tip chord: 150mm (~6″)
Wing section: Goettingen 613
Stab section: Flat bottom, 10% thickness
Stab area: 25% of wing area
Weight: 1200g (~42oz)

The fully sheeted wings were fixed to the fuselage with tongue and box. The elevator was initially covered with tissue. 

But after the first crash it was fully sheeted for greater stability.

We already had a 3 channel Metz Mecatron radio. But the original receiver was damaged. So I built a new 2-channel RX from a kit created and sold  by “Reuter”. This gave me perfect rudder control. The picture shows the radio installation: A 6 volt DEAC accumulator in the front, followed by the receiver and the Bellamatic servo. There was no elevator control.

The model flew very well and I had a lot of fun with it. At that time my father was a member of the FAG Kaltenkirchen and so I made most of my flights on their Moorkaten airfield. For high start we used 200m of fishing line. The high weight of the model was an advantage in the windy weather conditions of northern Germany.

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