Electrolite

FIRST PARAGRAPHS OF BUILD ARTICLE:

"Somewhere in England, it's late November - flat calm, 20°C a perfect day for Radio Control flying! Who are you kidding? Of course, we are indoors! With the rapid increase in leisure centres, indoor model flying activity has enjoyed an upsurge in popularity most, however, has been free flight. On the continent quite a lot of indoor R/C takes place, however, the cost of their 'super micro' gear is high at the moment. So after a hectic, though quite successful venture at the ME exhibition last year I felt it should be possible to design a practical model using existing micro gear.

After an intensive 12 month development period, which has provided a wealth of data on low speed flight, my first really successful model was produced, this used an 'ITP 02' with motor, rudder, elevator control giving a duration of 10-11 minutes. On analysis I felt it should be possible to use a KP 01 motor/gear unit - with the subsequent reduction in current consumption and, despite the doubts of Derek Knight of 'KP', the outcome presented here far exceeded my expectations.

DESIGN PHILOSOPHY: I favoured the pusher layout for two reasons, in it is safer both for humans and other models and the prop wash acting directly on the rudder gives the rapid response necessary at indoor venues. To save the weight of a servo I threw one out, or as they say up North- What ain't there can't weigh nowt! Height control would be by motor control. I incorporated an elevator in the design so that if unsuccessful I could add an extra servo at a later date, also I made up a simple 'pull' linkage to give up elevator in the turns to maintain altitude. For the first flights this was not connected and as expected made flying a little tricky at times, so I connected up the linkage and flying is a delight. By adjusting the horn length elevator effect can be fine tuned and, mostimportantly, it means only two channels are used. There are some very small 2 channel Rx's available bringing down the cost dramatically. I chose polystyrene foam material because of the speed of construction, and its resilience to crash damage. if you break it, with the right adhesive it's repaired in seconds.

ADHESIVES: Foam intensely dislikes solvent based glues - balsa cement, Evostick and normal cyanos - so use White PVA (rapid types most useful) or 5 minute epoxies (use only a smear). Special cyanos (Zap 'O' or similar). For the more flexible joints, such as laminating balsa to foam as when edging the fin and tailplane, or for instant repairs, 'Bison Col' is excellent. NOTE only 'Bison Col' in the ORANGE pack. Use this as a contact adhesive - smear each part, wait a minute, then join.

CONSTRUCTION: I shall not go into elaborate details, as anyone who has cut foam before will have no problems, if you haven't you will have fun learning and be able to use your new skills in other projects. I cut all parts single-handed (well, using two actually!) don't worry about the odd ridge, simply sand it out. Make up fuselage bottom pan first, add 1/16 balsa (use only light but stiff stock) add servo bearers, then add rear deck, wing mount, balsa gussets etc. Reinforce all stress points (undercarriage mounts) with small 'washers' of 0.4mm ply. Think 'weight' at all times, use glue sparingly - excess does not increase the strength at all, especially with foam. All the flying surfaces are simply 'hot wire' jobs. The main strength is in the leading edge, again use only best quality wood - light but firm - I used PVA Sellotaping until set. The trailing edge can be super-light wood as it is only there to stop foam from 'dinging' and to maintain shape, the same goes for the tail surfaces. Don't forget the pilot, it's quite easy if you cheat, like me, and fit him with a helmet - a profile pilot is an alternative. With 250 mah cells an all up weight of 8 oz is possible, but it will fly at a little over this. Use only first grade 'Virgin' foam as 'builders' foam often has been reconstituted, making it considerably heavier. Yellow Pages will reveal a suitable supplier under `Insulation Services' they will cut you the blanks to size from blocks of foam.

FLYING: With balance as shown test glide, only a gentle push, no `Javelin' efforts. Glide should be really good, long and slow. Have Tx on and see what response is like. Adjust glide trim by raising or lowering elevators and by rudder trim. With motor at 1/2 to 3/4 revs, launch gently - it's up to you now. It will ROG no problem and ground handling is excellent. It is really easy to fly and rewarding, requiring a bit of thought with rudder only control. Play with kick-up elevator to get level turns. Please experiment with it, this is an exciting and very pleasurable branch of the hobby, in ideal conditions!"