The little 10gram RC flyers

18 October 2021

And now a Britten-Norman BN-2 Islander?

Expanded polystyrene foam throughout.

1/2" for fuselage, sliced to two sides, held apart with foam spacers, glued together at nose and tail, sand nose to shape.

Glue tube to nose with nose gear temporary inserted.

Cut tail from thin sliced foam or 2mm extruded foam sheets.

Cover.

Hotwire airfoil to wing, add ply dihedral (real one has no dihedral, the ply dihedral is T-shaped so it can be glued in a slot on the fuselage)

1/2" for nacelles, gouge for motors, insert wires to slits in wings.

Cover with tissue.

Glue tubes to nacelles with main landing gear temporary inserted.

Glue RC gear in fuselage and make access slot for 1s cell.

Insert nosegear and main landing gear to tubes. 

Use paper template to trace front shield, windows, door and other outlines.

Acrylic paint is good choice.

18 October 2021

How about a RSAF Skyvan?

Fuselage from 2mm foam sheets

Sides

Top and bottom spacers T-section

Wings from 2mm foam sheets

Whole planform

Balsa 1/8 sq leading edge

Balsa 1/8 sq spar capped with 10mm wide foam strip

No ribs except for roots and ends

Sand to shape.

Since fuselage is wide, can use V-section as dihedral brace with wings glued atop and then V-section brace inserted into fuselage and glued.

Tail

All from 2mm thick foam.

Sand to shape.

Nacelles

Rolled foam or thick foam

Lift Struts, Landing gear support, wheels, RC gear supports

Made from various thickness of foam

 Cover with tissue

22 September 2021

Make a biplane or just extend the wing tips? Maybe it will fly even slower?

Making it to a biplane seems a bit of work although the flying speed might reduce to almost half.

I could extend with paper wing tips stuck on with double side tape? Maybe another 2 inches on each tip? 7+4 = 11". Paper should be strong enough to cantilever 2 inches. 11x2.5 = 27.5 sq in, 27.5/17.5 = 1.57, almost 60% more area. Maybe I get to reduce the flying speed by 25%?

10 September 2021

The 1s 50mah cells dies too easily. I have the plane and controller but no usable cell. So I had to buy another because I saw Eachine has a similar one with 3 batteries. Price increased, but I had no choice. And today I noticed they dropped their price! haiz....

This is what I bought.

Apart from the decoration on the model and the controller (this controller has EACHINE silkscreened), it is the same. The 3 supplied cells are 75mah though (the 1 cell that KF606 was supplied with was only 50mah), I hope the 75mah cells will last and will not die off within a month. Included in the bag is 1 extra cell clip. The previous KF606 did not come with spare.

Use the components for a twin engine plane?

21 August 2019

I bought this from Banggood.

It is a 2 channel indoor flyer.

Wingspan of 7", chord of 2.5".

Without deducting the radiused wingtip, Wing area is 17.5sq inches.

How about using the components to build a Whitehead 21?

I printed the previous Whitehead drawing in A4 and compared it with the Banggood model. The wing area and propellers' diameter looks about right, but the tail area is much smaller than the Banggood model. The  fuselage is too small to accept the single cell of 50mAh and electronic unit. If I enlarge it to A3, there would be no problem for the cell and electronic but the propeller would be so small. I don't know if there will be sufficient thrust to overcome the drag.

If I were to make one flyable model:

1. Wings are constructed from tissue, preformed on mold. Each wing has a curved leading edge and 2 curved spars to occupy the 1st, 5th and 9th positions glued on top of the preformed tissue. Spars at the 2nd, 3rd, 4th, 6th, 7th and 8th are representations, e.g. with strips of paper for a bit of stiffness to the tissue surfaces.
2. Photos of the original shows cambered horizontal tail but I will choose to make it flat for down pressure to increase dynamic stability. Ideally, the CG should be like a flying wing, but because of the camber in the wings, this would be too instable, so the CG has to be brought further forward and the horizontal tail at a negative incidence. Construction would be 2 leading spars, separated and stabilized by one spar. The other spars will be represented again on tissue before the spars are glued on.
3. For the fuselage. I want rolling wheels and easy access to the single cell and control unit. I don't know how I want to do that. Block of polystyrene covered with tissue? Paper is weight and will crumple easily.

28 October 2015

There's dihedral but no vertical fin/rudder. If I were to make one flyable model, the wing could be cut from 3mm foam sheet, linked by a pair of wire joiners to form the dihedral. The horizontal tail is similarly cut from 3mm foam but seperated to form a single elevator. A vertical tail and rudder can take the shape of half the horizontal tail. The wing and tail are glued to a box fuselage. A beam for the two 7 mm motors and hubsan propellers, wired up to a single plug that fits the WL929 939 board, should be glued onto the box fuselage and the battery goes under the receiver board, into the box fuselage. 2 pushrods are then connected to the controllable tail surfaces and the exposed servo horns. Finish up with bamboo bow and mast, complete with strings and wheels and a standing pilot with a hand holding onto the mast.