After grasping the basics of model flight with a three or four channel high wing trainer there exists a natural desire for most of us, to further one's skills with a more capable model. However, I reckon a gap has existed in the market for a good ARTF 2nd model for ages.
Natural progression from an ARTF trainer usually involves models such as the Mick Reeves Gangster, the Chris Foss Wot-4 or the Precedent Fun-Fly (now sadly out of production), amongst a long list of others, but crucially these have to be built from kits. Many of us don't have the time or inclination to balsa bash these days. So we've got ourselves a dilemma - until now!
The Black Horse Twister ticks all the boxes. It's an ARTF, is moderately aerobatic, has a tail-dragger configuration, and has a similar motor requirement to most trainers - thus reducing the outlay further. Clever! The only fly in the ointment is the requirement for a second aileron servo (one in each panel), making a 5 or 6 channel radio a necessity.
The genesis of this model is quite obviously the Precedent 'Fun Fly' - an excellent design, which gained an enviable reputation for teaching the basic art of aerobatics, but had to be built from die-cut balsa and lite-ply in the traditional manner. Rumour has it that the kit will be available again soon from the folk at SLEC, but in the meantime, the Twister brings the design bang up to date in ARTF form.
Specs are as follows:
54in. span
43in. length
Wing area 556.14 sq. in.
Rec. engine size; .32-.40
4.7lb AUW
4 channels (Rudder, elevator, aileron (x2 servo), throttle)
Right then, lets get in amongst it! What have we got? Very tidily finished components, a bomb proof alloy undercarriage, some rather odd looking polythene wheel spats and a wealth of fittings, including a solidly constructed glass cowling, painted to not quite match the covering and a bag of nuts bolts and screws, which unfortunately look like they fell out of the poorest quality flat pack furniture you could possibly imagine. Sorry boys, but fasteners with the mechanical properties of mild cheddar go straight in the bin round these parts… However, at less than sixty quid it is amazing value for money.
The basic construction is excellent, with snug fitting joints throughout. All control surfaces are pre-hinged and pinned from underneath in the manner of a certain German premium ARTF manufacturer- Are they made in the same place I wonder…
The heat shrink covering looks pukka - none of that nasty, brittle, sticky backed rubbish. The colour scheme is a very tidy yellow, with red and blue trim. Even the Llewelyn Bowen's amongst you would have to concede it don't look half bad!
The instructions comprise a glossy, crisply printed booklet, with clear photos of each operation and tick-boxes to annotate progress. A very useful list of tools and materials required to finish the model are also included. The instructions are written in clear English and leave little to chance. First impressions are good, hinting at a trouble free assembly…
Construction begins with the joining of wings. A length of lightweight box section extruded alloy functions as a wing joiner, plugged with balsa at either end to halt glue ingress. This is a new one on me!
It exhibits a number of indentations to allow the epoxy to key the panels together. It fits the joiner box with just the right amount of 'slop' to allow glue deep into the joint, rather than the glue being wiped off as the joiner is slid into position. The wings then being simply taped together until the joint has set. A little trick I recommend is to wrap the extreme wing root with masking tape before joining. It's then a simple matter to wipe off any excess epoxy, and remove the tape, leaving a very neat joint.
As mentioned previously, the ailerons are installed for you, having been pinned in true belt and braces fashion. The wing is configured to house a standard sized servo in each panel, with lead-outs preinstalled to pull servo leads back to the centre section.
I plucked a couple of Futaba 148's from the ever-fruiting servo tree in our garden (my favourite 9202's being out of season at present!) The servos are screwed to hardwood blocks on the underside of the hatches, making installation a simple operation. Nylon horns, plastic clevises and 2mm 'bike spoke' pushrods take care of waggling the ailerons. A balsa 'cockpit' sits over the wing and nicely hides the 4mm wing screws, and is itself doweled into F2 with a hatch latch at the rear to facilitate removal.
A butt-ugly carbuncle of a bubble canopy is pre-attached to this, ruining the effect. It's a real afterthought - destroying the rakish lines of the fuselage.
Sorry, but I couldn't help myself, a flick of the scalpel and t'was gone. Don't panic! I have a cunning plan…I recovered the whole 'cockpit' with some slick looking carbon Profilm. MUCH NICER!
With the wing complete it was time for the…
FUSELAGE
Work begins here with the fitment of an adjustable nylon engine mount to the firewall, and the assembly of the fuel tank. The motor bulkhead is pre-drilled and captive nuts are fitted, but the engine mount supplied was far to small for my chosen motor, an Enya .40. - Annoying because the motor was within the quoted range and I'd bought it special, like. A rummage through my collection of motors produced an OS 32, which wouldn't fit either!
Nothing for it but to knock out the captive nuts and fit a more suitable motor mount, which wasted the whole evening by the time I'd got it all lined up. Thank you Mr Flair by the way, for being the founder of my engine-mounting feast. So often you come to my rescue!!!
I reckon the fitting and alignment of the motor to be one of the most important things to be sorted by any ARTF manufacturer, so this wasn't the start I wanted. Not happy!
The tank was a curious fit in the tank bay once the throttle pushrod was in residence, with the back of the tank half an inch lower than the bung. Fingers crossed on that one then... I brushed a couple of coats of fuel proofer around the tank bay, for a belt and braces job, and then offered up the cowl, cutting the various holes with a mixture of Perma Grit tools in my trusty Dremel. The cowl was a reasonable fit, and the new motor mount gave the opportunity to get good alignment between cowl & fuselage.
I wasn't keen on the piano wire pushrod supplied for throttle operation, it was binding badly so was binned in favour of a more flexible Sullivan snake.
The tail surfaces were fitted next, with the wing bolted in place to ensure correct alignment. The gluing area on each component required the covering to be carefully removed. Don't score the balsa doing this though - fin and rudder detaching mid flight, do not a happy pilot make...
A smear of 5-minute epoxy had the tail surfaces in place. No jigging was necessary - the first time I can ever remember this being the case. Once again the elevator and rudder were pre-hinged and pinned as per the ailerons and waggled with wire-in-tube pushrods, with plastic clevises for adjustment. Given the straight runs down the fuselage they work quite nicely, driving some reasonable quality nylon clevises.
The sturdy alloy undercarriage is attached with 4 machine screws, complete with locking washers etc, and thus comprises a very solidly mounted unit.
In deference to our bumpy old strip I left the spats off. They didn't fit very well anyway, being markedly different than the nice little glass numbers illustrated in the instructions. I also bumped up the wheel sizes half an inch from the inch and a half supplied, feeling that the model would struggle to get away from our patch at this time of year.
So…what's left to do…A quick rummage around the box and the dawning realisation that she's ready to go save for a few servos in the fuselage, RX, nicad and switch.
FLYING
If you've skipped to this bit first don't apologise. I'm just the same!
So how did she go, (he says, scrolling through the usual list of cheesy plaudits and soundbites) With the specified control throws and C.G. placement the first flight was a total non-event. A couple of tanks of Irvine Sport 5 fuel were put through the motor on the ground to loosen her up, then a good range check and straight to the patch. With a Graupner 10x7 prop whizzing round, and a nice rich two-stroke we were off, picking up speed smartly. The tail came up and away she went. Sweet.
A few beeps of trim here or there, and a number of circuits to asses C.G., control harmonisation etc then loops, rolls, stall turns and inverted were all completed with aplomb. With the Enya 40 on song the model has adequate power, but is certainly no homesick angel. The latest OS46 might put a smile on its face though…
No surprises then. To be expected I suppose given the pedigree. A better test would be to give the tranny to a relative newcomer. So that's what we did!
I picked out one of our new lads, who had recently progressed onto a Wot-4 from his three-channel trainer. After a little cajoling he accepted the transmitter. I fuelled her up and left him to get on with it, watching with interest from the pits.
A sketchy take-off and a couple of circuits to calm down, then it was down to business! I must stop teaching him all my tricks… he got his head around it really quickly, performing some nice low and close figure eights in particular and looked like he was thoroughly enjoying himself, wheeling hither and thither…that'll do thank you very much, now gizzit back!
You want soundbites?
"Easy to fly"
"Doesn't run away with me"
"Not twitchy"
"Easy to land"
Well, I think the jury's returned a verdict. It was a hit with those that I thought might benefit most from it. It's a great little sport model too of course, with the C.G. a bit further back and slightly wilder control throws. It will serve me well over the winter months when I need something to lob in the car for a quick fly when the weather's a bit doubtful. Don't expect to be hovering, knife edging and waterfalling etc, all over the place. Stick with it's knitting - bread and butter aerobatics and circuit bashing! It's a good all-rounder, a convenient size, accepts standard inexpensive radio, fly's on a plain bearing .40 very well and is nicely finished.
Another toy for the growing collection then!!