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'Streaker' appeared as a plan and article in the October 2002 issue of Flying Models (the plan reference is CD179 if you are interested). I liked the look of the model but, what really caught my eye, was the arrangement of the elevator control. The design utilised a GRP arrowshaft as a tailboom with the elevator control being via a nyrod running through the shaft. The clever part was that the receiver aerial ran through the nyrod! A rather neat way of keeping the aerial out of the way of the pusher prop.

I had a 'Speed 400' looking for a home so began work immediately. The wing is flat and 36" span using all straight wood. The ailerons looked a little small (well, very small in fact) for an electric model, but the slow speed performance was claimed to be excellent. The wing construction appealed to me because it was intended to be built 'in the hand' with the webbed spar being assembled first and the ribs inserted. Curiously, the wing section was very similar to that invented by Phil Kraft for his various 'Ugly Stik' designs and having a flat bottom behind the spar so it could be built flat on the plan!

I dispensed with the removable canopy and inserted the battery via the wing opening. I also used one aileron servo instead of the two on the plan, with pushrods and bellcranks. If you look closely at the photos accompanying the article, you can see that the original also used this system.

I covered the model with Solarfilm 'Solite', giving an all-up weight of 17 ounces with 8 x 1800 mAh 'AA' size Vanson batteries from Maplin Electronics. I originally used two Supertec 'Pico' servos, but these were never up to the job and they were soon replaced with 'Naro' servos of the same make.

The instructions show the motor bound with wire onto the rear fuselage. This seemed to be overkill and I simply epoxied it in place, knowing that any hard impavt would simply displace it. It later occured to me that I could have epoxied a flux ring to the fuselage and had an easily removable motor.


This method of mounting the motor, coupled with the use of a Gunther prop, is very noisy! It has been compared to a Cox 'Teedee', but that's an exageration. The proximity of the ailerons to the prop also produces some interesting noises. The full throttle speed of the model is also quite considerable - it's very clean - and I don't think it really qualifies as a 'park flyer'. To be honest, I don't think any Speed 400 powered model qualifies as a park flyer and the Streaker is now the biggest of my electric models, though I have had bigger, heavier ones in the past.

A lot of up elevator trim was needed and I eventually packed the wing up to increase the incidence. All I can say is - it needs more!

The slow speed performance is also not as advertised and the ailerons really don't work, despite lots of differential. I'm used to adverse yaw, but these can produce adverse roll, which is disconcerting. I eventually cut into the ailerons and increased the area by almost 50%. I also added tip plates to the wing, which helped a little, but the basic problem is still there.

Inverted performance is best described as 'twitchy'. So much so that an axial roll is difficult to produce. I think that the wing section has a lot to answer for. I have the choice of living with it, or building a new wing with a proper symmetrical section. We shall see.


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