Categories
All english posts Biplane "Joyrider" Model Flight

Joyrider: Maiden Flight

After the first Center-of-Gravity tests my expectations have been thoroughly adjusted. I have to admit, at the beginning of this project I didn’t waste a thought on a possible failure. Meanwhile, the Maiden flight has become some sort of obstacle to me.

During the last weeks I’ve tried to accomodate weather, family and interested friends while taking patience and easing my doubts. That piled up too high: now or never!

A short remark: My wife thankfully took some video footage. However my PC has quit service, so I can’t postprocess. I will hand in the videos as soon as a new PC is at hand. Meanwhile, some still images will have to do.

Categories
Biplane "Joyrider" Model Flight

Joyrider: Setbacks and Corrections

Finishing the covering was another milestone for me and I was very confident that the maiden flight would turn out just fine.
Then the first complete assembly came along and with it some new challenges. Namely undercarriage and center of gravity.

Categories
All english posts Biplane "Joyrider" Model Flight

Joyrider: Covering

After the details are finished I can finally focus on the covering. Some model builders seem to regard covering as an irksome work and necesarry evil, but I actually enjoy it. To me it’s like a metamorphosis: the bare framing of the aicraft, as pretty as it is, equals a caterpillar, which is yet to become a butterfly.

Nonetheless it’s a lot of work all the more if one wants to get a creases-free result. In the process, I didn’t manage to take a lot of pictures, but I’d like to give an example and point out some crucial points.

Categories
All english posts Biplane "Joyrider" Model Flight

Joyrider: Last Details

By finishing the linkage the out-fitting has come to and end an I can take care of the last details. Those cover two areas: the fuselage and the wings.

The fuselage needs a couple of maintenance hatches in order to easily gain access to the drive unit, and the tailplane’s servos and fixture. The fuselages’ belly needs to get reinforced, too. And last but not least I’d like to add some details to the nose.

The wings need an additional strutting in order to stabilize the lower wings. And it will surely add to the good looks.

Categories
All english posts Biplane "Joyrider" Model Flight

Joyrider: Linkage

As soon as the tailplane’s servos fitting-out was done I busied myself with the linkage. To start off with, I made a few errors which had to be corrected. I will describe those errors as well as the solutions, so perhaps somebody can learn from my mistakes.

Since I’m not too sure what forces I will have to account for, I’m erring on the safe side. At any rate, I reproduced the linkage used with the Easy Glider and chose a combination of 1 mm steel rod, 2-to-1 mm and 3-to-2 mm bowden tubes.

Categories
All english posts Biplane "Joyrider" Model Flight

Joyrider: Fitting the Servos

Fitting the engine has sent my motivation soaring, so to speak. So I launched myself at fiting the servos.

Alas, I soon realized that my “planless” construction made my life a tad more difficult. In order to soundly fit the servos, the fuselage has to be reinforced and strutted. I had partially anticipated this and thus constructed the belly with very few slats. Nevertheless I’ve come to realize that one’s way better off if the servo mounting’s fixture is built into the fuselage from the get-go.

Categories
All english posts Biplane "Joyrider" Model Flight

Joyrider: Fitting the Engine

By assembling the tailplane the construction is finally finished, so now it’s out-fitting the model. As a matter of fact that’s already started since I fitted the aileron servos while building the upper wing.

I’m going to work my way through the fuselage from nose to tail. So today’s topic is set: the engine has to be fitted.

Categories
All english posts Biplane "Joyrider" Model Flight

Joyrider: Tailplane Assembly

Finishing the vertical stabilizer only leaves the tailplane’s assembly. Here, three important objectives have to be met: the horizontal stabilizer must be in parallel to the long axis, so must the vertical stabilizer, and the vertical stabilizer has to be at right angles to the horizontal stabilizer.

The most important contribution to the right angles is provided by clean, perpendicular cuts, which I can achieve easily thanks to my table saw. In order to further stabilize this orientation, I’ve constructed two guides from balsa wood and sanded them into a streamlined shape.

The vertical stabilizer's guide is in progress.
The vertical stabilizer’s guide is in progress.
Categories
All english posts Biplane "Joyrider" Model Flight

Joyrider: Vertical Stabilizer

The structural work is coming to and end: since the horizontal stabilizer has made much progress, it’s the vertical stabilizer’s turn.

Horizontal stabilizer and elevator reinforced.
Horizontal stabilizer and elevator reinforced.

Horizontal stabilizer and elevator reinforced.Even while building the horizontal stabilizer I realized I made a design error: the thin leading and trailing struts have been glued to the tips as butt joints, lacking adhesion area and thus stability. I rectify this by reinforcing the corners with small wedges of balsa wood. And this enlightment directly flows into the vertical stabilizer.

Categories
All english posts Biplane "Joyrider" Model Flight

Joyrider: Horizontal Stabilizer

The landing gear’s completion left only one step to finish the structural work: the tailplane. I copped out for a while to face this step because the tail plane ultimately makes or breaks the aircrafts stearability:

If it’s too small, you can’t control the model aircraft. If it’s too big, the bird responds like a proper boulder. This effect is additionally influenced by the fuselage’s length, as I’ve already mentioned while building the fuselage. That’s why I’m really glad to have found Christian Forrer’s web site, including an excel sheet for calculating model dimensions, before I started constructing my biplane in earnest. Based on the finished parts, I was able to determine the minimum size for the tail plane and get on with it.