The dilemma faced by beginners is very simple: buy a ready-built model or build from a kit. At this price, it is not surprising that people opt to buy the ready-built model. Everything is supplied: pre-built fuselage, covered wings, tail, full undercarriage including wheels, all control linkages and all nuts, bolts & washers which are required to complete the plane.
However, from experience we now know that, as usual with ARTF's, the undercarriage needs replacing with one of a triangle braced construction, the nose leg needs replacing with one slightly stronger, and the clevises changed for metal ones. The hinges supplied in this case were acceptable, unlike those supplied with the Thunder Tiger for instance. These cyno hinges work okay and help return the control surfaces to their normal position afar a maneuver. They are slightly stiffer than the mylar hinges as supplied by Balsacraft, so keep an eye on the on-board battery level for the first couple of outings. NOTE THAT THE SLOT GOES AT 90 DEGREES TO THE WING!!! i.e the slot goes into the wing and into the aileron.

The Build
I am am fairly experienced in building, so it was interesting to see how the instructions would guide a beginner. Happily they did mention the important points i.e. cut away the film where you are going to glue the various bits together. The did however, miss out the bit about securing the rudder to the fin. Don't fit the main undercarriage until last - it makes life a lot easier. However, I have since been asked a few questions which suggest that absolute beginners need more help than they are getting.

THURSDAY EVENING (2 HOURS): Spent about an half an hour opening up the slots where the aileron control rod exits from the wing. This was very tight and in use would result in rapid battery drain. Joined ailerons to the wing using cyno. Joined wing halves after some slight sanding of the wing brace. Put aside to set. Joined elevators to tailplane. Glued tailplane in place.

FRIDAY EVENING(3 HOURS). Fitted engine mount. Drilled extra hole in internal bulkhead for steering cable. Fitted steerable wheel. Removed covering in fin area and glued in place. Fitted servo to wing and adjusted ailerons. Fitted rudder to fin and fin to body. I used aliphatic glue for fin and tailplane, so I left the bottom rudder hinge until the following day before gluing to fuselage.

SATURDAY MORNING (5 hours). Assembled fuel tank. Fitted battery. Fitted remaining servos. Fitted control horns to elevators and fitted control rods to servo. Make sure the control rods do not bind when exiting the fuselage or you will drain your battery in no time. They are fairly easy to bend, so bend them. Then same with rudder. THIS WAS THE WRONG SEQUENCE - DO THE RUDDER FIRST, its a lot easier. When you fit the elevator and rudder servos, keep them as far apart as possible so that the control rods do not hit each other. Fitted undercarriage. Balanced model - NOTE THAT I HAVE NOT FITTED ENGINE TO ENGINE MOUNT YET!!. Move the engine on the engine mount until the nose is pointing slightly down. With the engine as far forward as I dared, and with the battery under the fuel tank, I still had to add 10oz of ballast to get the model to balance. Please note that the engine mount screws supplied are M4, and my Thunder Tiger GP42 needs M3 x 35 long. Cut small rectangle for battery lead (see pictures).

The intention was to do the shakedown flight at the SAA autumn fly-in, hosted by the Kinross club, when I went over on the Sunday. However it was just a bit too windy so we waited until the following Wednesday. Not to bad at ground level, but fairly stiff breeze at 50 feet. I am pleased to say that the model flew well on its first flight, tracking well into wind. A few circuits to trim it out ( couple of clicks right aileron, couple on the elevator), a basic Bronze schedule then in for a landing. Wing off, check everything is okay, refuel then back up again. I had set the full aileron throws to more than the recommended since it was still very windy, and set the reduced rate to those in the manual. It flew well on reduced throws so I'd say the 6mm quoted is good enough. More testing required though.

The Summary
A good model let down by one basic design fault (fuselage too long / nose too short) making it difficult to balance without a lot of ballast if you have one of the lighter engines. Although the wings do not have a fully semi-symetrical section (as per the Mascot or Hi-boy), they do have a reasonable curvature on the bottom of the leading edge, and the wing ribs are capped giving additional strength. Most importantly, there is virtually no gap between the wings, tailplane, fin, and the respective control surfaces due to the type of hinges supplied.

Ongoing Evaluation
On the engine front I would say that the GP42 does not have enough power to cope with the windy conditions we have to put up with, and either a decent OS40 or a 46 size would be better. It will loop but never with the confidence I would like. However, it is very stable in very wind conditions.

(April 2002) I have given up with the orginal engine and replaced it with an Irvine 46 Mk3. Take-offs are a breeze, and you can go into a loop from level flight. Rolls are acceptable and stall turns are also very neat.

Since I have dual rates on the rudder, I have reduced the second rate to 30%, making steering on a tarmacr runway a lot more controlable.

One modification I definately recommend is to replace the supplied undercarridge with the one shown in the pictures as it is much stronger. You will need to glue a 1/4 inch plywood inside the model to give the saddle clamps something to attach to. This is best done at the assembly stage and not afterwards. Remember to buy larger collets and saddle clamps.

I have also added a piece of brass tube inside the tank, between the outlet and the clunk. In the event of a rapid stop the clunk can be thrown forward and gets stuck, resulting in fuel starvation after about 10 minutes. I also used 30Amp fuze wire to secure the fuel lines to the tank on the outside, reducing the risk of air getting in. See here for details.

The latest mod was to add a fuel valve between the tank and the carburettor. This allows fueling and draining without removing a fuel line.

I simply do not know why ths model is yellow top and bottom as it impossible to tell which way up the model is when you get into difficulty. The red stripe is completely useless and should be replaced as soon as possible. The photo shows the underside of the wing with pink tips.This has been extended to cover all of the underside of the wing. The rest of the underside of the fuselage is fleurescent orange which is not as hi-viz as the pink. Go for red if you cannot get pink. It is best to do this mod before the wing gets covered with fuel, otherwise clean the wing with kitchen cleaner first.

Well, all good things must come to an end (or at least they can if you cannot do some basic repairs). One evening in August my son was practicing his rolls, loops, stall turns etc. During one of the inverted passes the model was gradually loosing height and eventually ended up doing a vertical landing. Since we are surrounded by soggy peatland, the resultant damage was not too bad. Okay, I needed a spade to reach the engine, but I was surprised to see how well it had survived. The wing was slightly damaged, the servo tray had come loose and punctured the sidewall, and the engine and bulkhead had come adrift.

I decided to recover the model while I had the chance but as there was a fair amount of fuel soaking on the exhaust side leading edge of the tailplane I took the opportunity to talk my son into a low wing model instead. Since I wanted something in a hurry and didn't want to build from scratch we settled on a Blackhorse Travel Air. My advice therefore is to go over all the seams of a new model with fuel proofer.

Remember, that as with all ARTF models, they are built to a cost and within a certain time limit, which means they cannot have had the tender loving care that you would furnish on a kit, were you to build one instead.

 

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