Goldberg Freedom 20 EP

[joe yap]

Many years ago, a friend of mine , Samuel aka 'Muah', bought his first high-wing plane kit from Carl Goldberg, the Freedom 20 which flew superbly on small 2 stroke engines. I was also one of the best looking trainer plane kit in the market in those days and costs only $90 back then. Although I was already flying pattern plane then, I was so impressed with the look and performance and I bought and built one for sport flying.

Mine flew extremely well with an old ENYA 25 size plain bearing engine and I had a lot of fun with it. It also looked so good that I hung it up on the ceiling as decoration when I invited my relatives and friends to my place on the day I registered for marriage.

Unfortunately, the messy fuel residue and engine vibration quickly causes cracks on the plastic cowling and wheel pants and ruin the finishing after hours and hours of flight. I gave it to another friend later when he needed something to learn to fly.

When the electric era kicked in, I was wandering whether I should build an electric version of it asthe modern equipment has since shrunk in size and weight. I obatined the plan from Samuel sometime back and is only recently, I started to redesign the airframe for electric.

This is what the original kit looks like.

[joe yap]

I've since made some changes from the original design. First of all, the entire fuselage was die-cut light plywood, but I'll use balsa instead, together with very thin plywood doublers. The wing ribs were 1/16" balsa but I do not have 1/16" balsa which is hard enough to be used as ribs. So I use 3/32" instead. Since I'm going to use thicker ribs, I reduce the total number of ribs and spaced out the rest accordinly.

To have more fun, I broadened wing control surfaces and divided them into 2 per wing. The inner surfaces will be used seperately as flaps and the outboard surfaces will be used as ailerons. This can greatly reduce the take-off and landing distances and steepen the landing approach which is useful for places like Punggol.

I'm designing the airrame for my AXI 2820/10 but I would think that it may to overpowered. Anyway, for the design purpose, I'll stick to that but I may want to change the power system later on.

I spent some time these 2 days to come to this far. The wing basic structure and sheetings are done. Left cap stripping, wingtips and flight controls to be cut free. The fuselage balsa side panels are fabricated and doubled with 1/64" plywood where the stresses are concentrated.

[edmond22]

Ok subscribing to Joe's poison again

[VinCopter]

Subscribed

[plug&fly]

Joe

Build this leh..

[mave]

Ya, build this one...

Build this leh..

[protyne]

Build this leh..

Vote 3 - Build Christen Eagle! Woohoo!

[leonlio]

Joe's Style

Joe's got his own STYLE... That's why he is called "DA MAN"...

The word? Smoooooth flying... and that's the work of the wings, not the motor, unlike what we're used to in our playground.

Finesse, the fine line between the master and the padawan.

The Christen Eagle? nah... too much like us.



Cheers,
Leon


(thread subscribed)

[muah]

nice =)

[joe yap]

Yesterday, I spent some sleepy hours making the fuselage formers. Instead of solid balsa or plywood sheet formers, I made them from 1/64" plywood/balsa laminates, which gives good strength and saves weight. The only solid balsa former is the one at the aft fuselage which I added to give additional fuselage stiffness and flexible pushrod supports.

I made the fuselage centre crutch with balsa/ply laminate as well and after that, it's building time. The parts matches well and the basic fuselage quickly takes up the shape. I have partially sheeted the rear fuselage and leave the rest for later, to give access for the pushrods installation.

The wings are mostly done up but I leave the servo mounts and flight controls till later, as I wanted to get all the major parts build up first.

[plug&fly]

Actually I was drooling over a picture of the Goldberg Freedom 20 in RC modeller magazine more than 15 years ago. It looked cool man, very handsome looking trainer. But at that time couldn't afford it.

[BullTerrier]

Build this leh..

This one also swee... da baby is based in nearby Senai. When it does the loops and spins your lunch quickly come up in your lap - jia lat...

[joe yap]

This one also swee... da baby is based in nearby Senai. When it does the loops and spins your lunch quickly come up in your lap - jia lat...

Senai? VH is Australian registered civil aircraft.

[Blackite207]

Hey Joe,
The freedom brings back memories for me too. It was my first plane...however I totaled it on approach and hit a crane

[joe yap]

Hey Joe,
The freedom brings back memories for me too. It was my first plane...however I totaled it on approach and hit a crane

Yah. It was like a yesteryear 'Parkflyer' to me. This one will relive the good old memories.