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"Petite Dreaming 850"ARF kit by Kyosho |
| Wingspan | 890mm (35") |
| Wing Loading | 45gm/dm 2 (15 oz/sqft) |
| Flying Weight | 560gm (20oz) |
| CG (percent of MAC) | 34% |
| Motor | Johnson RE380 (equiv. Speed 400 6V) |
| Propeller | Gunther 5"x4.3" |
| Speed Control | 10A with BEC and brake |
| Battery | 6 x Sanyo KR600AE NiCad (7.2V) |
| Receiver | Hitec HS-04Mi |
| Servos | 2 x Cirrus CS20 |
| Controls | Ailerons, Elevator, Motor |
| Construction | ARF (prebuilt balsa wing, blow-moulded plastic body) |
This was my first electric-powered model plane (a present for my 42nd birthday on Nov 1st, 1999 - thanks Ian!). It was quite easy to assemble (as might be expected from an ARF design), despite Japanese-only instructions. I installed an old 29MHz AM radio that I had lying around, but with very light sub-micro servos in place of the suggested standard units.
As I had not flown an R/C plane since the early 1980's, I was quite nervous about flying it. For its maiden flight I went out to the local park, with my brother Peter assisting while my friend Wayne recorded the event on film. Prelaunch checks indicated that I had the aileron servo linkages backwards, but I was too impatient and decided to fly anyway!
At first I tried ROG, which failed due to lack of a rudder (controls were ailerons and elevator only). Instead of taking off it simply groundlooped. So we decided to handlauch, with me controlling the transmitter while my brother launched the plane. He threw it, softly - whereapon it rapidly entered an attitude of 45 degrees downwards! OK, so now it didn't have an undercarriage anymore...
My next plan was to swap roles. I would launch the model while my brother held the transmitter, then he could hand me the Tx once the plane was aloft. We tried this several times, but I always 'lost the plot' shortly after taking control. Eventually the plane was too broken to continue flying.
A few days later, after repairing the motor and undercarriage, patching up cracks in the body and reversing the aileron linkages, I was ready for another go. Thus started a familiar ritual of fix-fly-bust, and my goal became to see if I could keep it in the air long enough for the motor cutout to activate (just over 1 minute!).
This plane flies alarmingly fast for a beginner, and I never seemed to get very far out before losing control. Eventually I found out why. When doing a moter-on range check(!) I discovered that my old AM receiver was picking up noise from the motor brushes, reducing effective range to only 50 Metres. So I bought a new Hitec 'Flash 4' FM radio set, which solved the interference problem. Finally I was able to control the thing properly, and started to gain some confidence and improve my flying skills.
I also made a few other improvements, including a graupner 6" x 3" folding prop and a proportional speed controller. The supplied 5 cell battery pack was not achieving expected capacity (I suspect this kit had sat on the dealer's shelf for several years), so I built new battery packs with Sanyo KR600AE cells. This increased motor run-time from 1 minute to 3 minutes!
Even with these better batteries, flight performance was still marginal.
Motorcalc indicated that Kyosho's AP-29 motor was too big for this plane. Apon
replacing the motor with a Johnson 380 (equivalent to a 6 Volt Speed-400), a 6
cell battery pack and a Gunther 5" x 4.3" prop, flight time increased to 6
minutes. Despite the less powerful motor, climb rate actually improved
slightly. I also made up a 7 cell battery pack, which makes flights more
lively, but reduces motor run-time to just over 5 minutes.