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"Nitestik"Scratch-built indoor flyer |
| Wingspan | 800mm (31.5") |
| Wing Loading | 13gm/dm 2 (4.3oz/sqft) |
| Flying Weight | 160gm (5.6 oz) with 110mAh battery |
| CG (percent of MAC) | 30% |
| Motor | GWS 'A' motor and 8:1 gearbox |
| Propeller | GWS slowfly prop 230x120 (9" x 4.7") |
| Speed Control | Kontronics Micro10 |
| Battery | 6 x Sanyo N110 or N150 NiCads (7.2V) |
| Receiver | GWS 4P |
| Servos | 2 x Hitec HS50 |
| Controls | Rudder, Elevator, Motor |
| Construction | Foam wing, carbon fuselage, balsa tail covered with Doculam |
This is my 3rd scratch-built design. It uses a standard GWS 'Litestik' powerplant, with lightweight GWS wheels, a carbon fibre boom and undercarriage, and a built-up tail structure covered in clear Doculam. The servos are coupled to rudder and elevator with nylon fishing line. The wing mount is formed by two separated layers of 1/16th inch balsa sheet, which also holds the Rx and servos.
Originally I built an entirely balsa wing with laminated ribs and leading/trailing edge spars, covered topside only with 1/32 inch sheeting. This was slightly lighter than a foam wing, but difficult to build and not very rigid. Somehow it ended up with washin on both wingtips, which introduced a nasty stall characteristic. The exposed framework also caused a lot of drag. The left side of the wing was heavier because I forgot to match sheet densities, but I balanced it out by running the Rx aerial down the right wing. Due to a combination of washin, too little dihedral and a small tail, the plane was hard control at low speed. Glitching problems at long range didn't help either...
After a sneaky tree jumped out at my plane in the dark, the wing needed extensive repairs. This was a good opportunity to consider an alternative. My friend Heather had a 'spare' (ie. broken) foam wing on offer. With some white glue to fix the break, and a redesigned mount, it fitted my plane nicely. This hot-wire cut foam wing has much better aerodynamics, so the model now can fly slower for longer, and is more maneouvreable.
I designed the Nitestik for flying indoors, but as yet we don't have a suitable local venue. Therefore I was tempted to try flying it in the park. The best time for flying is at dusk, when the wind usually dies down enough to allow enjoyable flights. To make this practicable I installed four colors of 'Super-bright' LEDs, angled to illuminate the bottom of the wing. This works quite well unless the model banks into a position where the lights can't be seen (I will add more LED's on the wintips and tail). Flying in pitch darkness against a fresh breeze is quite 'interesting' :-)