Arcfyre
Elite member
I am 34 years old, and I've been into flying RC planes now for the last several years. I have always built and flown FT designs out of foamboard. My father was into RC as well, back in the mid 1970's to early 1980's, before I was even in the cards. At the time, he was a college student living in Germany. There was no dollar tree foam board around back then, his models were made of balsa and plywood. Somehow, luckily, a few of his models have survived in storage to this day. I always thought it would be interesting to bring one of those old planes down and get it flying again, but other projects always got in the way. Last week, he and I decided to finally tackle it and see what we could get accomplished.
The plane we picked was built in 1979, by him, in Schweinfurt, Germany. It is a low wing monoplane with a nitro motor. Wingspan is about 50", and its covered in a yellow monokote. He named it "Esel", which is German for Donkey. The registration decoration on the side is still visible, D-ESEL. Here is how the plane looked when we took it out of storage:
The original motor was a nitro machine of which the displacement is unknown to me. It was completely seized, and despite disassembly and a long soak in mineral spirits, we could not get the thing to spin again (Anyone with experience with 40 year old nitro motors, feel free to chime in). While that was happening, We went through and tested all of the servos. All four servos worked, and with a little soldering, were converted over to modern female connectors instead of the old school male pin connectors. This makes the servos usable with modern 2.4 GHz radio systems, an upgrade we decided to make in the name of safety and reliability.
In the meantime, I decided to undertake a little scratch build to see how I would like a plane of this size. The lines on it reminded me in many ways of the FT scout, with some changes in dimensions. The horizontal stabilizer is a slightly different shape, but the vertical stabilizer and even the wing tips are just about dead on for the FT simple scout. So that is what I did. I scratch built a slightly larger FT scout. I stretched the wingspan to 60" and lengthened the fuselage by 5". I dropped the wing to the bottom of the fuselage instead of using the mid-wing scout design. As the original was called ESEL, I decided to name this one Ubungsesel, which translated means "practice donkey".
UE is a superb flyer. Floats like a glider, but still retains the scout's maneuverability. I may make a separate post describing that plane but suffice it to say it turned out really well. I even ended up painting it to emulate the original.
My father and I played pass the transmitter with the practice donkey for a few days. We were both impressed with its forgiving nature and its gentle characteristics. It was definitely a good plane to get him back into the flying scene again. It also showed him what modern electric planes are like, and after those few days, he decided to allow me to convert the original ESEL to electric, on the condition that I don't make any permanent changes so that nitro flight would still be possible.
The original ESEL is a fairly heavy airplane, as the majority of the parts are plywood, not balsa. I planned to fly it on 3S, so it was going to need a decent sized motor and prop to get airborne. I stole the power system out of another plane, a 40 amp ESC and a 3542-1135kv Turnigy Aerodrive motor, and worked on installing it on ESEL. It fit remarkably well, and I didn't even have to trim the frame rails that held the nitro motor. Yes I know it looks a little unconventional, but oh well.
I removed the fuel tank, and in its place, installed the ESC. The motor wires for the monstrous motor fit easily through the holes for the fuel lines, and after that installation was complete, I added a shelf of sorts to hold the battery.
C of G as always is key, and after trying a few different battery sizes, it turns out that a 2200 3S in the nose balances it out quite nicely.
So after all that was done, the only thing left to do was take it for a flight!
We took it up to our local flying area and set it all up. I was extremely nervous. My father gave me the transmitter for the maiden flight, which didn't help my anxiety at all. Just looking at this thing I couldn't believe that I was about to fly a 41 year old RC airplane.
I gave her some juice, and she took off sweetly. Flew like she was on rails, I was (and still am) blown away by how nicely this airplane flies. If I had to describe it, I would almost call it "slippery". The speed is incredible, and even with the throttle chopped, it just won't slow down. The monster motor up front is spinning an 11x8 prop like its nothing, and the plane just flies like its on rails. One thing that is very different is that the servos are significantly slower than the modern ones I'm used to. You give a control input, and the plane doesn't respond right away. It almost feels like a lag, but its just because those old servos take time to move. I blasted through the sky for a few minutes while my dad took some pictures of his old plane. I set up for a long landing approach, and to my immense satisfaction (and relief) I landed D-ESEL without any damage. It was an amazing experience.
There is some minor tweaking to be done. The horizontal stabilizer needs a little glue, and the elevator pushrod is a little sloppy, but the goal here to is take it up flying again tomorrow. If everything goes well, this plane will still be around when my son is ready to take over the sticks.
The plane we picked was built in 1979, by him, in Schweinfurt, Germany. It is a low wing monoplane with a nitro motor. Wingspan is about 50", and its covered in a yellow monokote. He named it "Esel", which is German for Donkey. The registration decoration on the side is still visible, D-ESEL. Here is how the plane looked when we took it out of storage:
The original motor was a nitro machine of which the displacement is unknown to me. It was completely seized, and despite disassembly and a long soak in mineral spirits, we could not get the thing to spin again (Anyone with experience with 40 year old nitro motors, feel free to chime in). While that was happening, We went through and tested all of the servos. All four servos worked, and with a little soldering, were converted over to modern female connectors instead of the old school male pin connectors. This makes the servos usable with modern 2.4 GHz radio systems, an upgrade we decided to make in the name of safety and reliability.
In the meantime, I decided to undertake a little scratch build to see how I would like a plane of this size. The lines on it reminded me in many ways of the FT scout, with some changes in dimensions. The horizontal stabilizer is a slightly different shape, but the vertical stabilizer and even the wing tips are just about dead on for the FT simple scout. So that is what I did. I scratch built a slightly larger FT scout. I stretched the wingspan to 60" and lengthened the fuselage by 5". I dropped the wing to the bottom of the fuselage instead of using the mid-wing scout design. As the original was called ESEL, I decided to name this one Ubungsesel, which translated means "practice donkey".
UE is a superb flyer. Floats like a glider, but still retains the scout's maneuverability. I may make a separate post describing that plane but suffice it to say it turned out really well. I even ended up painting it to emulate the original.
My father and I played pass the transmitter with the practice donkey for a few days. We were both impressed with its forgiving nature and its gentle characteristics. It was definitely a good plane to get him back into the flying scene again. It also showed him what modern electric planes are like, and after those few days, he decided to allow me to convert the original ESEL to electric, on the condition that I don't make any permanent changes so that nitro flight would still be possible.
The original ESEL is a fairly heavy airplane, as the majority of the parts are plywood, not balsa. I planned to fly it on 3S, so it was going to need a decent sized motor and prop to get airborne. I stole the power system out of another plane, a 40 amp ESC and a 3542-1135kv Turnigy Aerodrive motor, and worked on installing it on ESEL. It fit remarkably well, and I didn't even have to trim the frame rails that held the nitro motor. Yes I know it looks a little unconventional, but oh well.
I removed the fuel tank, and in its place, installed the ESC. The motor wires for the monstrous motor fit easily through the holes for the fuel lines, and after that installation was complete, I added a shelf of sorts to hold the battery.
C of G as always is key, and after trying a few different battery sizes, it turns out that a 2200 3S in the nose balances it out quite nicely.
So after all that was done, the only thing left to do was take it for a flight!
We took it up to our local flying area and set it all up. I was extremely nervous. My father gave me the transmitter for the maiden flight, which didn't help my anxiety at all. Just looking at this thing I couldn't believe that I was about to fly a 41 year old RC airplane.
I gave her some juice, and she took off sweetly. Flew like she was on rails, I was (and still am) blown away by how nicely this airplane flies. If I had to describe it, I would almost call it "slippery". The speed is incredible, and even with the throttle chopped, it just won't slow down. The monster motor up front is spinning an 11x8 prop like its nothing, and the plane just flies like its on rails. One thing that is very different is that the servos are significantly slower than the modern ones I'm used to. You give a control input, and the plane doesn't respond right away. It almost feels like a lag, but its just because those old servos take time to move. I blasted through the sky for a few minutes while my dad took some pictures of his old plane. I set up for a long landing approach, and to my immense satisfaction (and relief) I landed D-ESEL without any damage. It was an amazing experience.
There is some minor tweaking to be done. The horizontal stabilizer needs a little glue, and the elevator pushrod is a little sloppy, but the goal here to is take it up flying again tomorrow. If everything goes well, this plane will still be around when my son is ready to take over the sticks.
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