David Davis

Boomerang ARTF Repair Continued. Yesterday I removed the printed sticky-back covering from the fuselage and tail surfaces, fitted a 6mm (1/4") plywood plate to the underside of the fuselage to support the new undercarriage and replaced any damaged sheeting with new 2.5mm (3/32") balsa sheet from my scrap box. Please note that in order to save costs ARTF maufacturers align the balsa on the top and bottom of the fuselage with the grain running along the fuselage. You build a much stronger structure if the grain runs across the fuselage as you may see in the picture below. Today's tasks will include trimming and sanding the new wood and filling any small holes. Some of the fuel has got underneath the original covering and left a sticky mess in one or two places. I will remove this with cellulose thinner before covering can begin.

I'm sure that many of the engines in that picture are in serviceable condition or if not can be brought back into running order fairly quickly and cheaply but is there much of a demand for them? Sound second hand two-stokes may be picked up for a song these days as novices and experienced pilots alike prefer the quietness, cleanliness and convenience of electric flight or the economy of petrol engines in larger models. About ten years ago the chairman of my club went to the British Nationals. He told me that there was a man there with several buckets full of two stroke glow engines from little 049s to 25cc Super Tigres. £10 each. Take your pick...

Progress so far. All fuselage formers where the glue joint had failed were put back into place, clamped and cyanoed into position. Each former had small lugs on the side which fitted into slots on the fuselage side. The firewall, the former to which the engine mount is bolted, also fits into slots in the side. There was excess glue on the side of the fuselage from a previous repair which had to be removed to get a good looking result. I used a Stanley knife, a file and some abrasive paper to achieve this. I may strengthen the joint yet further by glueing some triangular section balsa behind the firewall. Two formers behind the wing's trailing edge had broken so I removed some of the top sheeting to improve access and repaired them using scrap 3mm (1/8") balsa with the grain running across the fuselage. I also fitted some 3mm sq balsa to support the top sheeting when it goes back. The next stage will be to fit the top sheeting then to turn the model upside down to repair the underside sheeting, then I will strip off all of the existing sticky-back plastic covering and re-cover the fuselage in red Solarfilm supplied by my club. While I'm at it I will introduce some 6mm (1/4") plywood to support an improved and more rigid main landing gear. With some reluctance I've decided to replace the Thunder Tiger 46 PRO with my beloved Enya 50. Unlike most trainers the Boomerang has a fully sheeted semi symmetrical wing. Consequently it's rather heavier than most ARTF trainers of its kind and needs a longer take off run to get airborne. While I am capable of achieving take-off speed on my club's 80 metre long runway a novice might run out of space first. The Enya will provide greater thrust. Realising that my building board was typically very untidy I tidied it up a bit for the last picture! Some say that an untidy building board is a sign of a creative personality. 😏.

Two good stories about Hi Boys. 1. Years ago I was walking down to the chippy one Friday evening when I noticed a fully built but uncovered Cambrian Models Spitfire in the window of a terraced house. I knew where most of the members of my club lived so I knocked on the door to ask the owner whether he'd like to join our club. "Oh no," he said, "I've lost interest. I want to sell the Spitfire and there's a Hi Boy too." We agreed a price and I sold the Spit to a club colleague. The Hi-Boy was complete and ready to fly with a Futaba radio and an OS40FP engine. There was some castor oil staining on the crankcase so I removed the engine and put it in the oven to soften the oil but I left it in too long and at too high a temperature and the entire engine came out a distinct shade of grey! Nonetheless it ran well. By that time I was quite an experienced pilot so didn't need a trainer and though I flew it, I didn't like it much so I decided to sell it. I had lived in Devon for fourteen years and every October or November the Exeter Club used to hold a vast auction with up to four hundred lots. I decided to go and stay with friends for a weekend and put the model into the auction. When its number came up bidding was slow so I stood up and said, " It comes with a transmitter and a mains charger as well. Just charge it up and go flying!" Well that started something and bidding went through the roof. I've never been any good at buying and selling things but I made a lot of money on that deal! As bidding ceased and the auctioneer went onto the next lot, a former clubmate said, "They don't fly very well do they?" 2. One morning a man called John turned up at the flying field with not one but two Hi Boys both fitted with OS 40 FP engines. He also had two old Futaba transmitters which did not have buddy box facilities. I started and tuned one of the engines and the club's treasurer flew the model before handing the transmitter to John. Even throttled back these models fly too quickly for retired novices in my opinion. Within seconds John had lost control and the model crashed into the treasurer's car punching a hole into the rear wing with its spinner. The car was a Volvo estate. John went on to learn how to fly on a Radio Queen powered by an Enya 40 four-stroke and within a few years became the club's chairman!

Found the video but you'll have to put up with me trying to trim out an over-powered Radio Queen first. Please make allowance for English not being the cameraman's first language. Mike Myers, just in case you didn't know a Radio Queen was the first model aeroplane to cross the English Channel between England and France in September 1955. https://www.youtube.com/watch?v=Mx8MphHxj9U

No!! Why do you ask? I built it in 2020 with my partner Miss Blue Eyes. It was the second Super 60 I built and I bought another one, a Penn Models Super 60. These were available as an ARTF long before ARTFs were even thought of. Most were finished with Cub Yellow fuselages and red wings and tails.

Strongly influenced by the Cloud Models scheme.

Making progress but still some way to go.

If I wanted to use a drone, or any other model aeroplane for that matter, to drop a bomb on a barracks or to disrupt an airport I'd be sure to register it wouldn't I? In France we've had to pass an on-line test which I thought was pretty meaningless, and to register each model we fly. Each model was then issued with a number which had to be stuck to the airframe and visible from 30 cms. I've stuck most of mine under the tailplane! We've recently all been issued with an individual pilot's number which is nineteen digits long. These also have to be stuck to the airframe. Quite why we've been required to do this is beyond my understanding. The pilot could be easily identified from the model's registration number.

It must have gone in inverted or flipped over on its back when it crashed. It was oos anyway, I only heard the crash!

The first job was to undo the throttle and steerable nose wheel connections at the servos, to remove the engine and firewall and to put it aside while I repaired the interior fuselage struture. I examined the fuselage formers and the servo plate. They were largely undamaged, mostly only the glue joints had failed in the crash. Each of the formers is located with little tabs lining up with slots in the fuselage, so having lined up all of the tabs I clamped the fuselage and applied cyano. We now have a pretty square fuselage. I'm aware that many ARTFers may not have a pair of clamps but a Workmate or even a vice could have been used.

I will recover the fuselage and tail surfaces but I won't attempt to reproduce the paintwork of the Boomerang. Note the orange patches on the tailplane which preceeded the latest crash. The wing is strangely little damaged.

My favourite ARTF trainer is the Boomerang mainly because it's semi-symmetrical wing allows it to penetrate a breeze better than those trainers with flat-bottomed aerofoils. When instructing you reach a phase when you have to allow your trainee to correct his mistakes. However, if the trainee becomes completely disorientated you have to take back control. If you're too slow the model crashes! It's the instructor's fault of course. When the club's Boomerang went in because both pupil and instructor became disorientated downwind in a stiff breeze, the model was comprehesively damaged. A few years ago I would have bought a new ARTF but with current prices I thought I'd have a go at repairing it. To us Greybeards repairing a model is something we've done many times before but it occurred to me that newer modellers who have only ever assembled ARTFs do not have this knowledge so could benefit from this repair blog. I'm also building a Pegasus Models Mystic and a DB Sport & Scale Auster so I won't be rushing its repair. I hope to be able to do a bit every week and will post pictures of progress accordingly. Anyway, this is what we're starting with.

I had arranged or my Belgian protegé Frans Cooremans to come to the flying field this afternoon to fly his Radio Queen. There was absolutely no wind and the temperature was a very reasonable 7C. I turned up with two models of my own, an ARTF Acrowot and an ARTF Super Frontier Senior trainer which is an ARTF SIG Kadet Senior clone. No sign of Frans so I rigged the Frontier and tried to start the engine, a new Laser 80 which has had three or four trouble-free flights to its credit. At first turn of the starter lots of unburnt fuel was ejected from the silencer. I found this strange as the Laser silencer isn't pressurised. Perhaps I'd over-choked it. Eventually I got the engine to start but it wouldn't pick up whatever adjustments I made. With two electric flyers observing proceedings, there were only three of us there, I gave up on the trainer and started the Laser 70 in the Acrowot. I took off and climbed to altitude, I was trying to find out how to fly the model inverted. In fact I just had to flip the model onto its back and take my hands off the sticks. I set the model up for a landing, the approach was impeccable... until I hit a tree on the other side of the road! Depth perception has never been my strongest suit! After twenty minutes of looking in the wrong trees we found the fuselage on the ground. All of the underside sheeting was ripped away and the tailplane is a mess. I can't comment on the damage to the wing because it's still fifty feet up in a tree! I'll have to wait for a gale! Teach me to fly ARTFs! That's the third Acrowot I've damaged in landing accidents. The first two which were kit-built models, were damaged when I landed them too quickly, not realising that an Acrowot is capable of flying both slowly and quickly. I now only have four models in flying condition: two trainers and two vintage models. Perhaps I ought to stick to that sort of model! ☹️ Frans never turned up at all which was a shame because flying coditions would have been ideal for a vintage model.

Welcome Naval. May I echo the advice you've been given above. I'd recommend that you visit some clubs in your area and discuss your situation with the membership. They may even have a trainer with which you can learn to fly before you go spending any more money. It would also be wise for you to buy the same make of radio as your instructor. That way he could bind your radio to his and you could fly on linked transmitters, the so called "buddy box" which allows the instructor to take back control with the release of a sprung-loaded button or lever. There may even be a few greybeards in the club who could help you with the build! However, if you'll take my advice, I'd start with an Amost Ready To Fly trainer and go onto the Flyin' King once you've learned how to fly. I'm sure that the Flyin' King builds into a good trainer going on its proportions but if you crash an ARTF, well that's unfortunate but if you crash something you've put a lot of time and effort into building, it's heart-breaking!

Several German fighter pilots flew in captured British flying clothing because it was superior to anything they were issued with. Adolf Ritter von Tutshcek perhaps being the most famous. https://en.wikipedia.org/wiki/Adolf_Ritter_von_Tutschek

Oh I don't know, one of my club members, a Frenchman, has a small electric powered Typhoon, an ARTF I believe.

I once managed to fly a vintage model in a flat calm on Mode 1 and my club chairman used to like to fly my Junior 60 using my Mode 2 transmitter. I must build another. When I lived in England I had a clubmate who could fly either mode he gave up the hobby and took up photography.

If you were to put up a list of what you've got with pictures, I'm sure you'd get fair offers from many of the people who post on this forum. "A Plane Olde Bargain will buy the entire collection from you. Their pricing policies are listen here: https://www.radiocontrolledmodels.co.uk/prices-and-valuations

I expect I'll see him on Sunday when we have a meeting to organise next year's programme of events. On the other hand he lives a fair old distance away and he became a father about eighteen months ago so his time is somewhat limited these days...

This is interesting. 4-Max's power suggestions for a Radio Queen, alright a completely different type of model compared to the Avanti, produced a model which was grossly overpowered and very unpleasant to fly. It was only by fitting a smaller motor and 3S battery that the flight characteristics were improved.

I see that it has taken me two years to get this far. It was intended as a "quick-build" but unfortunately both life and death have got in the way. I made a bit of a horlicks painting the canopy framing and will have to send off for another one when I get my pension!

I am going to give the cowlings to a bloke in the club who is the panelbeater with the local Volkswagen agency!

Like many of us who learned to fly before the age of foamies, I learned on a model with the wing attached to the fuselage with elastic bands. I still have three vintage models whose wings are fixed this way. I recall being told to attach the band to the front dowel first then stretch the band diagonally across the wing to the opposite rear dowel. Then to do the same with the dowels on the other side of the fuselage. Whenever I tried running the band from the rear dowel to the front dowel I was told that I was doing it wrong! Why is it so important to start at the front, stretch it over the wing and attach it to the rear dowel and not the other way round?

Took my ARTF Acrowot and my Big Guff to the flying field earlier today. Talk about chalk and cheese! The Big Guff first flew in 1938 and was probably the first model aeroplane to be designed specifically for radio controlled flight. As for the Acrowot, well we've all seen one of those haven't we? What they have in common is that they are both powered by Laser engines, a 70 in the Acrowot and a 62 in the Big Guff. The wings on the Big Guff are retained by elastic bands and as I was fitting them I remembered being told as a novice r/c pilot over thirty years ago, to hook them over the front dowel then stretch them over the wing diagonally to the dowel at the trailing edge. Why do we do it this way? Somebody once explained why but I couldn't understand! Pictures of the Big Guff below. You all know what an ARTF Acrowot looks like!