text:
1/32" she F2 et top dec F3 k F4 F1 F5 Profile pilo t Wing rib temperate ply plat e FB Telco 3/32 x 1/16 shown, Co2 motor 1/16" Sq " 1/16" ply mounted on plate onto F3 FB 1/16" Sq 1/32" ply skid 22 Swg wing bra ce wire s
T dec Top king 22 Swg wire axle Hard 1/16 1/32" she " Sq trail et coverin ing edg e g Cockpit cut-out FREE FLIGHT ● CONTROL LINE ● RADIO-ASSISTED
Typical win 1/16" thic g rib sectio tion k wing ribs
www.aeromodeller.com March 2017. No. 958. £5.00
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Editorial: Editor: Andrew Boddington Email: email@example.com Publisher: Alan Harman Administration Manager: Hannah McLaurie Office Manager: Paula Gray Advertisement Manager: Sean Leslie Editorial Design: Peter Hutchinson & Alex Hall
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08 PRODUCT REVIEW THE SPARMAX ARISM COMPRESSOR COMBAT? TIM HOBBINS EXPLAINS WHERE TO START. Tel: 01525 222573 Fax: 01525 222574 Subscribe: 12 issues - UK £55, Europe £73, Worldwide £82 IS TESTED AS A MODELLER'S SPRAY AIR SUPPLY. Website: www.aeromodeller.com
60 REVIEWED BY MARIS DISLERS. FROM THE ARMCHAIR AeroModeller is accurate, the publishers and printers cannot accept liability for errors and omissions. STUART 'SUPERCOOL' SHERLOCK Advertisements are accepted for publication in
26 BETTER… HABITS – PREPARATION RAMPS UP THE SUPERCAPS. AeroModeller only upon Doolittle Media's standard terms of acceptance of advertising, copies of which
64 DAVE HIPPERSON TAKES THE REINS TO are available from the advertising sales department AERO POST of AeroModeller. HIGHLIGHT ATTRIBUTES THAT WILL GET YOU READERS' LETTERS BY POST AND WINNING. EMAIL. Free Plan is Mike
66 Watters' Blackburn TAIL END CHARLIE Monoplane. THE THOUGHTS OF CHRIS OTTEWELL. 3
D Sport and Scale display team.
W End of an Era - Conclusion hen I wrote the End of an Era editorial a couple as a team – dad said that nobody else would put up with him! of months ago, it was in the expectation that As well as being the centre of family life she could be found in my mother Jill Boddington would be living a the aeromodelling backroom in the 1960s counting out nuts comfortable retirement in the same village as and bolts for accessory packs in DB Models kits, or sewing my sister. Sadly this was not to be as mum lightweight nylon 'bags' to cover wings on models for the died unexpectedly on 20 January 2017, just 2 days short of her Flambards TV series in the 1970s. 83rd birthday. Old Warden model events were a family affair for 50 years, Due to the demographics of aeromodellers, with many being with Mum helping run the transmitter pound when dad was still over 60 years old, it is an unfortunate part of my job that I editing, and after dad died 7 years ago, she attended with me receive regular notifications of deaths of much loved characters. to catch-up with old friends. I always struggle to know whose obituary to run as I want to So as I and our family mourn the passing of Jill Boddington, keep AeroModeller looking forward, and I usually focus on class I ask you to think of those people who may not get directly leading individuals and those associated with the magazine. involved in your aeromodelling life, but who support you in your However for once I will 'pull rank' and acknowledge my mother, endeavours. who was the wife of the late David 'Boddo' Boddington, as she was well known by many modellers. Regards, Andrew Boddington My mum and dad were contrasting characters who worked firstname.lastname@example.com
UP & COMING and you should check before travelling in case of change. For future inclusion of your events, please send an email with date and details of the event in a format similar to those shown below to firstname.lastname@example.com
SPARMAX ARISM VIZ COMPRESSOR A new airbrush sized compressor from the Airbrush Company is tested by Andrew Boddington.
A s a builder of flying models, where there is an airbrush one needs a ranging from a car tyre (unwieldy, if one wants to apply a dependable air supply. I've been using frustrating and 'damp' air), propellant paint finish but keep the airbrushes on and off for 40 years when canisters (expensive and don't last long), model light an airbrush a model requires a fine finish, and in and compressor units. is the tool of choice. And that time I've tried various air supplies My last compressor was huge, suitable
The 'Silver Bullet' is unobtrusive below the airbrush and does not interfere When the airbrush is placed in the moulded holder on top of the compressor with the operation. The air bleed control is the knurled knob at the top, while it switches off the pump. the water drain is a push valve at the bottom.
for spraying a full-size car, drew a full with partitions and packing to keep the pressure I need is determined by 13 amps from the socket with the risk everything secure – thus avoiding that watching the practice spray pattern and of fusing the circuit and was so loud I sinking feeling when your item arrives in adjusting it accordingly. needed to wear ear-defenders! It was not a squashed box! The pressure is adjusted on the bleed what I would call handy for a modeller. As well as the ARISM Viz compressor valve which is built in to the 'Silver So what I needed was a compressor that unit, there is a mains power adapter, Bullet' - this fits on the end of the air was suitable for my existing airbrush for a 2m braided pressure hose, a 'Silver hose underneath the airbrush. The 'Silver efficient spraying of small to medium Bullet Plus' moisture trap and pressure Bullet' also acts as a moisture filter; it sized flying models, would be quiet adjuster, and an airbrush rest come is clear allowing any captured water enough to allow pleasant inside use, yet 'Smart-Stop' (more later). The mains to be visible and then released via the would be compact enough to be stored adapter provides the 12V supply required drain valve. So what is important about in my workshop until next needed. by the compressor, but there is the a moisture filter? If water droplets are When the Airbrush Company sent alternative of an optional battery pack so mixed with non-water based paints details of the new Sparmax ARISM Viz that the compressor can be used away such as cellulose or enamel you end up Compressor it seemed to fit my needs. from mains electricity. with tiny 'pin-pricks' on your paint finish A look at the Airbrush Company website The compressor unit is of sturdy where the water evaporates. for the details of the compressor (search construction with sheet metal sides. on www.airbrushes.com for part C-AR- There is the air outlet and a pressure There she Blows! VIZ) confirmed that my NEO Iwata TRN2 gauge on the front, and on-off switch at Having connected everything up and was a supported airbrush for pressure the back. The pressure gauge dial and switched on, I'm immediately struck by and flow. numbers are relatively small making it how quiet the compressor is. No need difficult to read exactly, but being an to wear ear defenders and I can still What's in the Box? analogue needle gauge this does not listen to King Crimson on the Hi-Fi! As The Sparmax compressor arrived well matter too much as one can easily see I didn't have a model ready to spray for packed in first a thick-walled shipping the position of needle – I find that I this review I tested the Sparmax ARISM carton, and inside that the retail box don't often read the pressure gauge as Viz compressor using my own airbrush
loaded with water thinned acrylic to is switched off saving energy and want a paint holding cup/bottle of at spray paint on large sheets of card – I preventing over heating - the duty least 14cc (1/2oz), and a wider spray want to be sure the compressor has cycle of the compressor is 40 minutes pattern than for plastic models meaning the oomph (i.e. pressure and flow) to continuous use, after which it needs to a needle of at least 0.5mm diameter. You cope with the spray finish on the wings be switched off and allowed to cool for can use smaller airbrushes but it will take and fuselage for a typical medium sized at least 10 minutes, but I doubt many you longer to apply the paint! If you're a powered model. This it did without modellers would get close to this limit large 1/6 scale modeller or equivalent, problem, the bleed valve on the 'Silver with normal use. My airbrush fitted you may want to go larger still with your Bullet' allowing adjustment of the air comfortably in the holder as well as it airbrush, and if a humongous 1/4 scaler pressure to suit whether I wanted thin or supporting Sparmax's own airbrushes. a paint-gun rather than airbrush may be wide lines. The dual-action pistol trigger The Sparmax ARISM Viz compressor is more suitable. ● on my airbrush meant that the airflow a well thought out air supply which would could first be engaged to stabilise its make a great addition to the 'armoury' flow and then on full depression the paint for builders of flying models. was released – a good even coverage Sparmax ARISM Viz was obtained with spray width of about Choosing an Airbrush and Compressor Specifications: 1.5" (4cm) maximum. The compressor Compressor • Low maintenance, oil-less single piston air compressor had no problem keeping this airflow If you are new to airbrush finishing of • Working pressure from 0 psi to 50 psi (3.4 going so that I could cover the test models, the bit of advice I'd give is to bar) • Silver Bullet Plus moisture trap pieces. first choose your airbrush to suit your • 2M Braided hose This compressor as with many coverage or lining requirements, and • Airbrush holder • Pressure gauge 'hobbyist' products has no air tank, then choose the right compressor to • Air flow: 16 - 18 lpm (0.57 - 0.64 cfm) at so there is a slight drop in pressure as provide the indicated pressure and open flow • 1/8 BSP outlet on compressor the air is released through the airbrush. flow. Remember our needs are slightly • Size: L20 x W12 x H18 cm (7.9" x 4.7" x This is not a problem for my painting different to the small-scale plastic 7.1") • Weight: 2.5 kgs (5.5 lbs) needs but if you need a smoother, modeller who requires fine detail • Noise level: 45±dB more controllable airflow, a higher spec (perhaps closer to the area coverage Sparmax ARISM Viz Compressor C-AR-VIZ compressor with storage tank (to hold requirements of a spray tan salon!) A £175.00 inc VAT. the pumped air) is the way to go. good starting point when wondering Sparmax ARISM Viz Compressor with Battery and Charger Z-AR-VIZ-BATT- An innovative feature of the what to buy is the Airbrush Company CHARGE £210.00 inc VAT. compressor is that the clear moulded website, choose the 'Info' tab - they also The Airbrush Company Ltd airbrush holder comes with a 'Smart- have knowledgeable experts on the end 79 Marlborough Road (East) Stop' switch. This is to be found on top of the phone. Lancing Business Park West Sussex BN15 8UF of the compressor, and by resting the When choosing an airbrush, keep in Tel: +44 (0)1903 767 800 airbrush in the holder, the compressor mind that for our coverage we'll probably email: firstname.lastname@example.com www.airbrushes.com
Repairing Damaged Allan Voyce takes you through the steps to re-tap threads and revive discarded engines.
Q British engines.
A motorised drilling machine makes life are available, for our use a light vehicle easier when a hole needs to be drilled engine oil or similar will suffice. I bigger to suit a larger thread, and I have have found that a regular spray with found a small pillar drill is useful for most penetrating oil gives an excellent finish applications, except when the part is too on threads cut in aluminium. When awkward a shape to be held safely and cutting a thread, the tap or die should square to the hole to be drilled on the be rotated ½ a turn, then turned back machine. ¼ turn to cut off the swarf produced as Before a thread is tapped, the hole the material is cut. This should be done has to be the correct size to ensure a full until the whole thread is cut, otherwise thread depth. Drill and tap size charts the new thread could be torn out as the Photo 5. 4mm thread tap in the drill press chuck are available on the internet or from swarf builds up on the cutting edges of ready to be brought down to the cylinder jacket. engineering supplies, however metric the tap or die if they are not backed off thread sizes are easily worked out. The regularly. thread I'll be using on the compression screw repair is 4mm x 0.5mm. The Stripped Diesel diameter of the thread is 4mm, and Compression Screw 0.5mm is the thread pitch, which is I've had quite a few model diesel the distance between the peaks of the engines through my hands where the thread. The drill size will be 4mm minus compression screw has been stripped 0.5mm= 3.5mm. trying to free off a gummed up contra- To ensure a good clean cut thread, piston. The engine I'll be using is a DC the tap or die should be well lubricated, Merlin .75cc. The first thing to check or the finished thread will tear as it is is the next largest size bolt that will cut. Although special tapping fluids comfortably be able to be used to Photo 6. The cylinder jacket is turned by hand to tap the thread.
accommodate a full depth thread in and bolts. This prevents the end of the on low speed, the compression screw the cylinder jacket. I tend to use metric screw becoming mushroomed from lever section can be filed to shape. The bolts as they are readily available. Try constant use against the contra-piston, profile I have shaped is comfortable to passing a drill by hand through the screw and removing the thread in the cylinder use, especially for tight contra-pistons hole, and once you have the drill size, if the screw is removed after being used (Photo 11). A lathe could be used for you can work out which tap size can be for some time. The longer cap screws this process if you have access to one. used by using the formula outlined in the are only threaded part of the WEAR EYE PROTECTION! previous section. The same can be done way on the shank, and this DO NOT WEAR LOOSE for other threads using a tapping chart makes for a tidier finished CLOTHING OR to cross-reference the drill size against compression screw. ANY JEWELLERY the tap that can be used. Try not to use Screw the cap screw WHILE WORKING fine threads in aluminium, as a coarser into the cylinder WITH MOVING thread is stronger due to the depth of the jacket (Photo 7), MACHINERY! thread. and see how much The drill that fitted the DC head was thread is showing Photo 13. The 3.5mm, so it can be tapped to 4mm x above the cylinder. completed 0.5mm pitch. Sometimes you may have Remove the screw, compression screw ready for use. to drill the hole a little larger to fit the and cut off any excess next size tap. To make sure the thread thread, making sure to is tapped at right angles to the head, a leave enough thread for Due to the hardness pillar drill can be used as a tapping jig compression adjustment. File of the allen cap screw, by locking up the chuck using cable ties or grind a slight taper on the end of it needs to be heated until the around the fanbelt as shown in Photo the thread, this is to take care of any section to be bent is red hot, or it will 4. NOTE THE POWER PLUG TIED IN mushrooming that may occur through crack or break at the bend. It can be THE FANBELT IN PHOTO 4 TO AVOID constant use. Note: if you screw a nut heated using a small butane torch ACCIDENTAL MACHINE START UP! onto the screw before cutting and filing, available from hardware shops (Photo The thread is tapped by fitting the when you remove it, it will clean up any 12), or your local motor vehicle repair thread tap in the drill chuck, placing the "rags" left from these operations (Photo shop or engineering shop could help cylinder jacket on the drill press table 8). Cut the head off the screw, leaving here. Note the 3 nuts are left on the and bringing the tap down into the hole enough shank for the length of screw screw to avoid damage when it is in the cylinder jacket (Photo 5). The lever you want, including a small amount gripped in the vice, and a small spanner cylinder jacket can then be turned by needed for the bend, which is described or piece of tube is used to provide hand to cut the thread (Photo 6). further on. leverage while bending, and also to keep Lock 3 nuts onto the screw (Photo fingers and hands clear of the heat. Making a new 'Comfortable' 9), tightening them against each other Photo 13 shows the completed screw, Compression Screw so the flats line up. This is done so the and fitted to the engine in Photo 14. I use Allen Head cap screws to make thread is not damaged when the screw compression screws as they are made is placed in the pillar drill chuck (Photo Tommy Bar Compression Screw from harder material than normal screws 10). Using a file, and the drill press The cap screw is cut to length as per the
Scale Matters Bill Dennis builds another winning release from the Vintage Model Company and surveys the coming year for FF Scale.
VMC Sopwith Camel captures the essence of the Camel whims. The most important is to add The output of small scale models from perfectly, with correct wingtips (often working rigging, which I did recently for the Vintage Model Company is gathering portrayed with straight edges), the the first time on the Avetek Tiger Moth. It pace, such that it is becoming difficult right wing gap and the characteristic adds greatly to the strength and I would to keep up. The latest is the Sopwith Camel 'sit'. The tail is enlarged but say it is essential. While these kits are Camel, forming an ideal partner for that is a concession to make the thing a huge improvement over the KK ones the previous SE5a. This series of kits fly. With everything basically accurate, of yore, the one area where I prefer the is designed by Andrew Darby and is the opportunity is there, for those so original is the centre section struts intended to be a modern take on the Keil inclined, to embellish it to their which used to run right Kraft and Veron designs. I was lucky hearts' content. down to the bottom enough to get one of the first Camels I made a very few of the and have just completed it. alterations, just Again, the level of detail on the to suit my plan and the accuracy of the fits are own extraordinary, and the wood selection superb. Once assembled, the model
fuselage where they were firmly some Williams cylinders of the correct being admired. anchored. Without some bracing, these size. These are easily split in half with a Next up from VMC is a Corsair. struts could easily break away and the Stanley knife down the moulding seam. model would be very difficult to repair. I made a mess of the paper 'plywood' Stahl Curtiss Seagull I know this after my toolbox wandered panelling around the front fuselage. I have never built an Earl Stahl design, about in the car on the way back from My first attempt with brown paint was only because hitherto I have built few Oxford and did a bit of squashing on horrible; next time round I printed some rubber models. Nevertheless I have the SE5! Rigging is easily done: use wood grain off the internet. This was always been aware of the esteem in 'bait bayonets' from the fishing shop much too bright but a couple of coats of which his designs are held and they (£1.99 for 20) poked in and cyanoed as pine woodstain improved things. certainly have a deserved reputation as anchor points, and 2lb brown fishing Flight tests await but the fact that fine-flying machines. The many plans line, pulled tight and held with short the model flies well can be seen on are well-drawn and practical, looking pieces of crimped aluminium tube. Just Youtube (search 'VMC Sopwith Camel'). surprisingly modern structurally. be careful not to accidentally cross the To maximise performance, My interest was stimulated landing and flying wires when doing this one could lighten the by photos online of a – I understand there are people foolish tail surfaces quite a very nice Stahl Waco enough to do this, and more than once… biplane, but while Having covered the model, I used a Paul Briggs has looking for different brand of non-shrinking dope built this very the plans on to my usual, which led to a tiny amount nice Waterman Racer from Outerzone I of curved dihedral on the top wing. All Aeromodeller came across NSD shrinks a little, but I find HMG does December this Curtiss 1984. Only so the least. However, a Camel with a one of this SO3C-1 perfectly flat top wing can look droopy machine which was was built, and sad; my Camel looks perkier without and there kitted by being noticeable, so don't worry if a little are only Flyline, and two photos, curvature creeps in. but it makes I changed You are probably aware that I prefer a up into a course. very cute and painted finish, and I sprayed a thin coat fine-flying little Between having of my usual Flair/Spectrum PC10. I have model. the plan printed got used to the paper markings and I and what you see used them here, except for the rudder bit, and also shave here uncovered is and upper wing, which I knew I would be away some of the rear four days. It is a long time unable to do neatly; these were painted. fuselage. The model will also since I have built a model using The markings in the kit do not include need a lot of down and sidethrust; at the keel and stringer fuselage, and it fuselage roundels, but these are easily least 6 degrees. This will be somewhat has opened up a whole new world of found on the internet and re-sized. disfiguring so you may wish to make up mistakes to be made. Nevertheless, the Rather than mess about with dowel a dummy noseplug and scale prop for model went together quickly and easily. and thread for the engine, I found I had when the model is just sitting on the TV Most of the fuselage notches lined up
This is how far the Strutter had progressed by the Christmas break. Note the representation of the delicate 'latticework' around the nose, and scale undercarriage. The potentially troublesome rigging of the CS struts is rendered simple by the use of jigs. The rear rubber anchorage will be beefed up.
pretty well but I made a big mistake with Lodge, along with a large contingent of pay. A combined event with like-minded the upper keel by using separate pieces SAM35 members, the purpose being to modellers is more practical and SAM35 (as on the plan) and leaving a gap where assess its suitability for our activities. have booked October 1st for a meeting the rear cabin is. Inevitably this led to the The field is about the same area as Old and invited us along. structure twisting and I had to rescue Warden but it is a much more convenient the situation by glueing a bridging strip shape and will work with different wind Strutter kit across the keels to straighten things directions. Better still, the surrounding You may remember the recent Tiger up. When it was all done, I took a piece land is all part of the same estate and Moth kit from Avetek in New Zealand, of half-inch dowel, wrapped coarse retrieving errant models should not be a which was reviewed here last year. sandpaper round it and scalloped the problem. They now have a new release in the formers between the stringers. I think this It will not be feasible to run a scale- form of a 28" Sopwith 1½ Strutter and is worth doing; a stringered fuselage on only meeting because we do not have I was delighted to receive one of the a metal aircraft is already a compromise, sufficient active modellers to make it first kits through the post. To say it is a made worse by formers sticking through the covering like ribs on a 'supermodel'. The only change I made was to add a cross-brace inside the fuselage at the point of the TE; this is where the fuselage will collapse on a one piece model when the wing gets knocked back. There is nothing to be said about the wings and tail, other than they were easy and well-designed. Finish is Humbrol enamel over Esaki tissue, with paper markings. Unusually for a rubber model, it naturally balances where it should.
Derek Knight's Auster will be eligible for the AM/MA contest at the FF Nats in This is a photo from April 1944 AM of the original uncovered late May. Have you got your model ready yet? Auster model.
R egular readers will recall our Team Racing. However, as we pointed through a magnifying glass, does not report on the Fora Junior out in our earlier report, when pushed have the obvious crystals that are 2.5cc (0.15 ci) engine from to maximum performance potential, a inevitable with high silicon casting alloys. issue 933, February 2015. couple of structural weaknesses That ought to mean the new piston Since then, a dedicated RC became evident. and cylinder are less prone to thermal glow Junior has become available and distortion and cracking. Wrist pin is a we believe that this new version will Development light interference fit in the piston bosses also become the regular fixed-choke The new version has been significantly and at 11.5mm long, sits somewhat short diesel/glow Junior. We'll call it the 2016 modified, such that only a few minor of the retaining circlips. A new conrod Junior. While looking little different at first parts are carried over. The earlier 14mm design has a rectangular cross section, glance, it contains significant revisions. and 16mm bore-stroke arrangement is not circular. Enough for us to take a closer look. replaced by 14.5mm bore and 14.9mm The original crankcase is retained, Recapping, the Junior is intended as stroke. The new, slightly shorter cylinder but has a larger groove on the exhaust a sport engine and as an introduction has one less cooling fin and is machined side to clear the wider conrod. The new to competition work, but is priced from bar stock, not the earlier casting. one-piece hardened steel crankshaft significantly lower than true competition The new piston is also from bar stock will of course overcome any potential engines. They have proven popular in and has a 5.9mm diameter window on wandering crankpin problems. Less Club competitions and for Classic FAI the boost port side. And when viewed obvious is the move away from slit
New cylinder (right) is machined from solid, has revised port angles, larger bore and is shorter than the earlier Junior type (left).
spraybar end to a synthetic rubber gland classes, but maybe an option if the older lowering RPM. Recovery from this clamped by the dome nut against the piston/cylinder sets are discontinued as condition, when opening the needle spraybar tip, to seal against air leaks and spares. Port timing then becomes milder setting, was not rapid. Therefore, this hold the desired needle position. – around 142 degrees exhaust and 118 engine is best operated with a slightly As before, our engine came with the degrees transfers and the head would rich mixture setting, where it runs quite head button for a long reach normal need to be shimmed higher for the extra steadily. And at this size, the carburettor glow plug, if the owner wishes to run stroke. Or a suitable spacer between would not be well suited for aerobatics or it that way, along with an alternative cylinder and crankcase could also combat work, where a more consistent F2D style venturi insert. Its 4mm choke be used. fuel supply is required. point is very near the top, then diverges Compression adjustment is quite to almost 6mm diameter, before the Diesel mode insensitive, especially if you are steep conical taper of the lower section. With that easy cylinder to crankcase accustomed to a contra piston with Four jet holes are set somewhat below fit, it was no surprise that normal finger full cylinder bore diameter. That means the 6mm position, clearly with the choking did not draw fuel from the fuel one eighth or a quarter turn to make expectation that some form of pressure tank. We found that measuring around any noticeable difference. This engine fuel feed method is used – probably a six drops of fuel into the carburettor tolerates an over-compressed setting, latex bladder. The regular venturi insert adequately primed the engine for not by overheating and reduced RPM, for suction feed has a steep conical taper starting and the engine seemed to run but by a rough exhaust note and only to the 3.9mm diameter choke point, with perfectly happily. As an experiment, slight loss in RPM. That tolerance is four peripheral jet holes immediately we temporarily added a packing shim good in a way, but puts much more below, in the steeply divergent around the cylinder's exhaust port area strain on the internals and should be lower section. (made from aluminium drink can, held in avoided. As always, go with the minimum One final observation was an place with balsa cement) to better seal compression setting before performance unusually generous radial clearance against crankcase pressure/vacuum loss. drops off. of approximately 0.08mm (0.003 While not a perfect solution, that allowed Generally, the Junior 2016's in.) between the lower cylinder and us to finger choke the engine in the usual performance curves are very similar crankcase. This area containing the ports way, but seemed to have no measurable to the earlier version, although torque and crankcase passages is usually fitted effect on performance. at lower speeds is significantly less. quite snugly to avoid loss of crankcase General handling in diesel mode was Maximum torque occurs between 13,000 pressure to atmosphere. A simple very good. We noted that the carburettor RPM and 15,000 RPM, so it was no pressure test confirmed this potential design was perhaps chosen for its good surprise that the engine was not very leak path on our particular engine. pressure drop at the fuel delivery point. comfortable when loaded to lower Incidentally, this engine could be In practice, optimum mixture setting speeds. Power peaks around 17,500 assembled with the earlier crankshaft, for best power output was unreliable. A RPM where it delivers 0.47 BHP, but which would increase swept volume momentary change in flow could then you'll get most of that across 16,000 to 2.64cc. Oversize for competition have it misfiring, with less fuel delivered, - 19,000 RPM. At even higher speeds,
Despite almost the same effective choke area, the short "suction" venturi View of pressure venturi from below. Shows shallow divergent taper from (right) is designed for maximum pressure drop at the fuel feed area. Taller choke point at top, to maintain smooth laminar air flow, before fuel is design (left) for pressure feed aims for maximum air mass flow rate. injected through four jet holes below.
Part 30 BETTER… HABITS - PREPARATION
S Dave Hipperson looks at the personal actions that lead to success on the flying field.
omeone once said that when models of the correct design. So now continue writing. we fail we do it a little bit we can attend to the small details. This The following steps are preparing for at a time. In other words article should take you up to the moment the fray or going into battle. Success we let the tiny details slip you launch the first comp flight of the planning should be a little like a military and eventually it all comes day. In future months I will endeavour to exercise, and as with all plans there crashing down. If you have read what explain some tricks which help getting should always be a 'B' and if not at least has gone before in John O'Donnell's it back. The ideas below are born out the willingness to adjust tactics in the columns over the past months we can of fifty years of my own competition face of the unexpected. Tactics you presume you are interested in flying experience but mostly originated by notice, not strategy. Strategy comes first well and winning, or at least competing the man I hope I am only temporarily and that's deciding what you want to competently and hence enjoying deputising while he considers whether to achieve – tactics are the tricks you use yourself. Furthermore if you have taken notice of what he has been saying you should have well-built, strong, straight
Ian Davitt's model box. Keep everything in the box all the time and it is less The modern F1A towhook has come a long way since someone stuck a pin likely that you will arrive without your tail planes. (Photo by Sue Hipperson) in the bottom of a model and hooked up a piece of string. All this equipment has to be regularly maintained.
on the field to achieve it. to be checked and talked to nicely so slightly less than pretty temporary repairs There is a competition coming. There they work the next time. Repairing and you might have made during the contest. are classes in it for which you have making up new rubber motors was Now electricity has inveigled its models. Is there one event that you always most therapeutic for me – like way into free flight it is necessary that wish to win particularly or think you can, cutting out wing ribs. I loved it. I know you check batteries constantly. Have or are you perhaps hoping to do fairly most of you don't – I understand but it a routine. Radio DTs are a wonderful well in a couple with thoughts towards has to be done. convenience but not so effective if Championship, or Plugge Points, or Power models take a pounding from the batteries are flat or disconnected! whatever? Decide this clearly before you vibrations that you might not notice. Your transmitters and your lap tops all go. Decide your priorities, your strategy. Always check the timers and engine have these too. Checking and testing bolts etc. and wash out any motors that is essential if you have RCDT and/or Repairs have been in the dirt. Whilst lovingly electronic timers. Your preparation should have begun cleaning them you can check for damage immediately you came home from the to the airframe. Gliders are subjected to The Models last contest, in as much as there is likely enormous loads. Check nothing nasty I have had people mention that they or not some repair work to do, no matter has happened to structures in the wing never saw me make a trim flight at a how minor. I always liked to do this as root that may not be immediately visible. contest. This is pretty much correct. soon as possible whilst it was fresh in Lines, knots, nicks, frays and even, have I wouldn't say I never got out an my memory, particularly in the case you brought all the components home? untrimmed model at a contest but it of rubber where open models always Back at home all airframes can of course was rare. Time is invariably tight and if sustain some damage and motors need be patched neatly, replacing those it isn't then the more time you have in
With planning it's possible to get a great deal into a small space. Saves weight A neat compact model box is useful. This one belonged to the master of the art and room in the car. This example is Phil Ball's box of F1Bs. the late Anselmo Zeri. Half a dozen Wakefields in here. Not even heavy. I built one similar, but it weighed twice as much.
hand, and the better you can use the classes in different boxes then double before you fly again. Check fuselages conditions, eventually the higher you will check that all the necessary components are straight and undamaged, any auto place. My trimming was done 'at home'. are in there. I have a good friend in the rudders work, and timers operate (If only!) Actually for the last fifteen years Midlands that thinks I am now going as they should - tensioning devices, my local site was just over 30 miles to tell you the tale of the time he went especially if elastic bands, are prone away. I would expect to go there 15-20 abroad and forgot all his Wakefield tail to perish (even if slowly). I appreciate times in a typical season or well over planes. It's OK Russell, I am not going to that the most modern airframes require 1000 miles driving per year just to trim. mention it. somewhat more than a visual inspection Additionally the trimming of some small Are they trimmed, when did you last and condition of contacts and batteries classes` (Cd'H, CO2 and Mini Vintage fly them, what happened? It's useful are important as well. Complicated glider Rubber) could be accommodated on a if you keep notes on each one. I keep hooks can gum up just as easily as very local field if the weather was perfect. little cards in the appropriate boxes motors, check they are free. In the case Try to take trimmed models with you – telling me when I flew each model last of power models carefully check the there should not be time for test flights and how it was. (Not it's contest record plumbing, especially the loose neoprene and if you think there is you are only – that's unnecessary – just whether it or silicone bits. Things that give the most risking the models as the environment was behaving itself or not.) If you fly just trouble on rubber models are usually the at a contest is usually rather unfriendly one class this may not be absolutely prop blades not folding. Mine had a habit particularly if it's an aerodrome. Too necessary but if you fly many it most of stiffening up occasionally, check they many hard things to hit. certainly is. Are all the flying surfaces are free and oiled along with the prop The night before the competition at flat, or if not, warped in the right places? shafts. Prop blades not folding correctly the latest, check the models even if only Flat is easy, but so as to be able to still wreck more flights than sophisticated to be sure you have the models you quickly check for changes by eye, I electronic timers malfunctioning! thought you did in the box(es) you are write the warps on the trailing edges, planning to take. Don't laugh – it's been tips and dihedral breaks. This is also Back Up Equipment done, turning up with the wrong models. useful if a model receives damage or Without all your ancillary equipment, or If you are lucky enough to have sufficient gets very wet during the day. You have even without one tiny crucial bit of it, storage space to keep your different a visual way of checking the warps your day can be made uncomfortable
The Hipperson Kontiki Swift Motor Home circa 1999 here after spending the night on the Tidy example of the 'hatch back parked into wind' form of side of the field awaiting next days Paris Cd'H event. Can cause its own weather problems preparation protection. Here Pete Watson prepares power but useful if you want to bring absolutely everything. Usually has a ladder on the roof too. model on Salisbury Plain. Note most things safely in tidy boxes.
F or many years I have attended article stated that at some point in indoor model flying meetings. the aircraft's short existence, it did One particular model I often have tapered wings, whereas, all other saw being flown was an early Blackburn designs had constant chord design from the Blackburn wings. This is not a true scale model, Aircraft Company that predated the but as a slow flying indoor design, and Blackburn Monoplane (Foggin's Flyer) it works well. that can be seen at Old Warden. This Once acquired the model languished model belonged to Derek Hardman of for some time untouched in a box. Solarfilm fame. The Blackburn was a Then with inspiration resumed, the test model for the new material he was model was resurrected for a new indoor developing at the time – Litespan. season. It did need a bit more repair The Blackburn could be seen at than I originally thought. Looking at the each meeting, slowly flying around and model again, I realised that the only with no apparent trim changes, being salvageable part was the fuselage. So powered by a reliable Brown B-100 I did a re-build, and as I knew it was CO2 motor. a design that flew very well indoors, Events happen and Derek gave up I measured up the model and did a indoor flying after becoming unwell. drawing with a few constructional Sometime later, I heard that Derek's changes. models and some items were being What follows is my re-interpretation offered for sale. I was particularly of the late Derek Hardman's original interested in the CO2 motors. I was design. With a bit of extra work you surprised to find that his original could change areas of the nose or Blackburn model was still there, substitute a constant chord wing to although in a somewhat distressed model other variants of the Blackburn state. A deal was struck for items, Mercury with their respective engines along with the Blackburn. People who (Renault, Isaacson, Gnome or Anzani). knew this model could not tell me I continued to use a Brown CO2 motor which or what particular Blackburn it in my re-build, but the little Blackburn was. An internet search brought up would be suitable for an electric power an article that described it as more train and would even take conversion than likely being a Blackburn Mercury from FF to Micro RC. Primarily the III (or possibly IV depending on how Blackburn Mercury has been designed you number them) circa 1911. The as an indoor model but it would also
3/32 x 1/16"
22 Swg aluminium tubes
F2 F3 Tail from 3/ F1
22 Swg aluminium tubes
Fuselage Start by laying down the two top side longerons, over the plan top view. Add the two triangular formers FB and then, what is the 1/16"sq. bottom longeron. Position the 1/16"sq. spacers, building Derek Hardman was the founder of Solarfilm and a keen indoor flyer, always willing to experiment with up the fuselage into its triangular shape. new ideas. Then insert the diagonal strips between the spacers. The structure can now be handled and the top formers F4 & F5 added. Former F3 will be dependent upon which power source you are using. Continue by building up the nose block
Recommended Reading
ply plate FB FB
F3 Acetate sheet wheels F1 F2 F4 F5 3 off 1/8" sheet 1/16" sheet FB 1/16" sheet F3 1/16" sheet 2 OFF
H 22 Swg wire axle Top decking 1/32" sheet covering
1/16" Sq 1/16" Sq
Wings These are very lightweight structures. Start by cutting 28 balsa ribs, from 1/16" sheet, using the template shape shown. The template may be made from very hard balsa or plastic card. The ribs are formed by simply cutting along the rib template outline, then offsetting the template 1/16" at the leading and trailing edges and repeating the process. The leading and trailing edges are strips of hard 1/16"sq balsa. Add each rib in place as shown on the drawing, cutting down each one to size. With each wing complete, turn them over and cyano the 1mm diameter carbon rods spars to the ribs. Check and adjust the alignment of the wing support wire tubes against the wires protruding from the fuselage and then also cyano the tubes in to place on the wing. The top nose decking has been simplified on this semi-scale model but you could go to town Tail and Fin with an dummy exposed engine.
Covering As this is a lightweight model, it only requires a lightweight covering material. On my model I decided to keep with the model's original intention and used Antique Litespan from Solarfilm, shrinking with minimal heat.
A simple wire undercarriage together with thin ply skids and clear plastic wheels hint at the scale structure.
Undercarriage skid
Cut successive ribs by moving the template down by 1/16" each time. The carbon rod spars are cyanoed to the bottom of the ribs. When finished the wing only requires covering on the top surface.
The wing supporting tubes are best checked against the wires from the The fin and tailplane should cause no concern for the average builder. fuselage before cyanoing!
STARTING VINTAGE COMBAT – PART 1 F TIM HOBBINS SHARES HIS EXPERIENCE TO ENCOURAGE NEW ENTRANTS TO CL COMBAT FLYING. ADDITIONAL PHOTOS BY MICK LEWIS. or me, it was one through it. A few minutes later was 22 years ago, at which limited to 26 seconds for 10 Saturday afternoon I closed it and went to put point Vintage Combat had laps but I cannot remember in York when I it back when I saw a word I been alive and thriving for anyone actually achieving this strolled into WH hadn't seen for years - Ruter- some 5 years; today it's the speed. The governing body Smith to sneak a ess! It was the August 1994 healthiest it's ever been. is called the Combat Flyers crafty browse through the copy of AeroModeller, Frank As a quick overview, Association, who usually car magazines while the wife Smart's article on the famous Vintage Combat uses the CL organise and run about 8 or was in River Island… you model was highlighted on the combat designs from the 60's 9 competitions, including the know how it is. I found the front of the magazine. I picked and 70's with diesel engines. Nats, throughout the season latest mag and started leafing it up and started reading. That Vintage Combat is speed which lasts from April to
October. The competitions and huge fun. control line combat flyers in of people near to you, so are held at such venues as Mick Lewis wrote an the United Kingdom. If you you can arrange to meet Old Warden in Oxfordshire, introductory article in the are new or wish to become up, practice etc. Secondly Darley Moor Racetrack near 934 March 2015 issue of involved in this exhilarating there are often supplies of Ashbourne, RAF Scampton AeroModeller. The main sport then you will find plenty materials and equipment in Lincolnshire, Berkeley near purpose of this article is to of advice and information posted which never see the Gloucester and hopefully the further encourage those here" says it all really. Once light of day anywhere else, new BMFA National Centre thinking of taking up Vintage you've had a read through, and thirdly you can ask and once again Barkston Combat, give more detail and email Mick Lewis and ask questions and get pretty Heath. There are prizes at check out some of the many to join the CFA - its free and much immediate answers. every competition and there's resources available to the you will be added to his Varied and contradictory an annual league so you can newcomer. email list for regular Updates answers admittedly, but check your progress. and Newsletters with offers, answers nonetheless. It's These days we usually get Do Your Research which is invaluable. A browse great for current news, somewhere between 25 to 40 There are a lot of active through the archive of the combat gossip and chat, and entries at most competitions; combat flyers spread Newsletters will give you a keeping in touch with other along with the stalwarts and throughout the UK and taste of what happens. Also flyers. Perhaps not so great famous names from the past, combat is much better as a join the national body the as a reference tool because this will include newcomers social activity. So one of the BMFA because you need to the time line keeps rolling, joining the ranks throughout first steps I would take is to have insurance cover, and the pushing earlier subjects the season - mostly returnees try to find other flyers local to BMFA hold the rule book for further down. who 'had a go' years ago where I live. No matter what Vintage Combat along with The Barton Forum when they had long hair you read there is no substitute other national classes. www.controlline.org.uk a (or even hair) but also the for having a root round Facebook www.facebook. longstanding mecca for occasional cross over from someone's workshop, picking com 'Fraid so! Search for Control Line enthusiasts, it another discipline, having things up, looking in detail the group 'UK Control Line has a Combat section which wondered what all the fuss is and asking questions. The Combat' and send a joining goes back years and is easy about. Don't get me wrong, best place to start looking request. This is a very active to search, so if you have a we do have a few youngsters, for these people is online. If group with almost 400 basic question you can bet it's mainly sons and daughters you are not a PC user then members, to which the vast been covered on this forum at of existing flyers but in the at least give me a call and I'll majority of UK (and some some time. It also has a very main the average age is 60 find local contacts. Here are overseas) flyers contribute. interesting article on how to plus. Vintage combat is a 3 places to look online: There is usually something win at combat, which I really lovely class, we are blessed Combat Flyers Association going on every day to keep must read again. with a supportive organisation website www.combatflyers. us all interested, many people and competitions have the co.uk Start here as the share their views, skills and Combat Community added attraction of being very mission statement "We are opinions freely so it's useful in The one thing I will say - every friendly gatherings as well as dedicated to promoting many ways. Firstly, when you person flying combat today being exciting, hard fought and providing support to all join you can see the locations will be very keen to help you
1 2
ask either in the Facebook than Matthew carrying out aware the Parra, Rothwell play and not have to change group or at competitions. these wishes and keeping and JO.19 have hard chrome the engine under pressure. Additionally, in the second the Oliver Engines alive. The bores, they last for ages, and You don't really need 6 part of this article, we'll talk JO.19 based on the Oliver the more you run them the though! about combat practice and Mark 4 crankcase has been better. So initially, I'd get one the motor you buy for your a popular choice since its and after running it in, use it Models: Design and early competitions will make introduction and is a used by as often as you can - you'll Number an ideal practice motor. many flyers. benefit by getting used to If you're intending to enter As you become more Also made in the UK is its handling characteristics many competitions, then involved, if you turn up at any the PAW 19 TBR. The best and it won't deteriorate. The I would advise turning up combat event and look at the thing to do here is give Tony early Rothwell 320's are now to your first with at least 4 hardware in use, you will see Eifflaender a call and tell him coming up to 6 years old and properly trimmed models that that there are a lot of Rothwell that you want it for Vintage still going strong. So bear this have been previously test 320's in use, followed closely Combat. Available from PAW in mind when paying for them; flown. As these break or just by JO.19's and Parra T4's in Macclesfield +44 (0)1625 £250 for 6 years hard work die of old age, keep adding and a small number of very 423891. isn't a lot is it? It is handy to this number. Models do special, hilariously fast The Australian Rothwell to have a couple because if get broken - fact of life – but PAW.19's. With regard to 320, used by many top flyers, you get a refly after a midair there aren't so many that availability, this is the current is still in limited production, collision that damages your end up totally destroyed first state of play: but there is a long waiting list. model, then you can bring or second time out; most Following Tom Ridley's sad If you want one then get your model/engine number 2 into models broken in a bout passing production of Oliver name down early as it will ceased, however having been be a while before your motor in touch with Tom's wife Julia, arrives. I am delighted with the fact And the Parra T4, available that production will continue. from Club Tamaran in Gran Here are Julia's words "Matt, Canaria (www.control-line. our son, intends to continue eu) and made in the Ukraine. the Oliver Engines in line with There was a waiting list at the Tom's wishes. Tom had been time of writing but the motors coaching him for the past should be in stock by the time few months and wanted the this article goes to print. original Olivers to be available These engines are all in memory of J Oliver senior, about the same price, just and JSO. I shall continue to shy of £250 and all similar help Matt as I have always performance. How many do done with Tom." you need? Well, obviously What better tribute to Tom at least one, two is ideal. Be Liquidator XL's and Shoguns under construction by Tim Hobbins.
Resource sites The Ironmonger 69 is one to consider when starting Vintage Combat. This one is built by its designer, Richard Evans. Combat Flyers Association www.combatflyers.co.uk
Barton Forum www.controlline.org.uk
Facebook, search for 'UK Control Line Combat'
Plans Simon Miller firstname.lastname@example.com
Kits Mike Waller email@example.com Nick Stowe firstname.lastname@example.com Mick Lewis firstname.lastname@example.com
Engines Oliver Engines JO.19 firstname.lastname@example.com
Rothwell R320 firstname.lastname@example.com 44 AeroModeller - March 2017
T he Bowden is one of the which have failed to score in one or both are like myself of the older generation few competitions in the Free rounds. and all are experienced modellers - I Flight Nationals, other than I do not consider myself an expert in hope this article doesn't come over too the scale, that has spectator this competition by any means, having much like 'teaching your grandmother to appeal - and it also attracts failed to score at my first attempt and suck eggs' as it is certainly not intended one of the largest entries. It is also a only achieving 4th place in my second. that way. If it helps somebody then I will good first competition class to introduce There is no magic formula for winning be pleased, and it would also be great beginners to competitive power flying. this competition, as in any other if we could introduce the competition to Having acted as CD (Contest Director) competition an element of luck on the younger people. of the Bowden Trophy Competition day is a big help. However, there is no for three years running, I have been substitute for good preparation. Where to Start? disappointed with the number of entries Most of the entrants in the competition It must be stressed that the first
David Leeding with his timer equipped KK Outlaw with which he managed a fourth place in the year prior to taking on the CD mantel.
requirement before entering any the event. The Tomboy is a good flier, but - it should balance level or in a slightly competition is to READ THE RULES! it was designed by Vic Smeed to be an nose down attitude. The BMFA Contest Rules, Section 3 easy to build and fly model for relative Test flying should first be carried out Free Flight (Outdoor & Indoor) book is beginners to powered free flight - in without power to achieve a satisfactory available from the BMFA office and can this it has excelled. However, with its glide, if the glide is too steep then also be viewed on the BMFA website at slab sided fuselage, straight wings and packing should be placed under the www.bmfa.org The appropriate section tail it is not the most attractive model rear edge of the tailplane starting with is found from para 3.47 thro' paras and it is marked down accordingly 1/64" (preferably plywood to prevent 3.53.5. - The Bowden Class. when compared with, for instance, the crushing) increasing in thickness after It is worth quoting the objective of curvaceous and beautifully finished each test glide until a nice flat glide is the competition 'This trophy is intended Aeronca Sedan entered last year. It is achieved. If the model is stalling then it to encourage the design and flying of also worth mentioning that the winner may be necessary to pack up the leading Sports Models with cabins or cockpits of the 2016 competition and the runner edge of the tailplane to achieve the flat able to hold an imaginary pilot. The flying up were both flying own designs, not glide required. With the glide sorted of these models in a controlled manner necessarily the best looking and finished then commence short low powered is an exacting competition of Precision, models, but the good flight scores and flights, these may well require the glide Flight Stability and Appearance'. characteristics together with reasonable trim to be changed but the first change In brief the competition is flown in two deductions meant they scored enough to consider is the thrust line of the rounds with each having a target flight points to win. engine (plate mounted engines make time of 45seconds (from the release Be aware that we have tightened up adjusting both side and downthrust a of the model to the completion of the the scrutiny of models against the rules, lot easier). It is a trial and error iterative landing). Each competitor starts with 100 and in particular it should be noted that process until the optimum compromise points in each round and the objective is rule 3.47.2 states 'The model shall have between power and glide performance to finish with the maximum total number a cabin with clear glazing or a cockpit is achieved. Ideally the model should be of points for the two rounds. Points are with a suitably sized aperture and a clear flown in different wind conditions (when deducted for failings as detailed in the windscreen.' the Bowden is held at Barkston in May, it BMFA rules referenced above. Whatever model is chosen, it is is rarely not blowing a gale!) important that it is built accurately Finally one should practice ROGs The Model to the plan with the incidence angles (Rise Off Ground), not easily done as Having familiarised oneself with the rules, correct. When rigged with the wings there are so few opportunities to fly free the would-be competitor must decide and tailplane, look to ensure they are flight from a hard standing. Remember what model to enter. This is one of the level and in line. On completion the the undercarriage position on vintage most important decisions as design and most important first step is to check designs may owe more to protecting appearance can result in the loss of a the balance, the CG (Centre of Gravity) the wooden prop, rather than directional large number of points. It is not good is usually shown on the plan. If not ground control. So, select your model enough to dust off an ancient Tomboy, then a 'rule of thumb' is to balance the design with thought for the take off. But patch a few holes and squirt a drop of completed model ready to fly without fuel be aware that the class rules also state diesel into the ports to free the engine with a finger tip under each wing near the '…in adverse conditions at the discretion the day before the competition, not if you fuselage at about 25 to 33 percent of the of the CD the flying requirements and would like the best chance of winning chord measured from the leading edge associated scoring may be appropriately
Steve Glass had an interesting own design low winger in 2016 powered by a PAW 1.49. Let's see something other than Tomboys in 2017!
A Guide to the Free Flight Duration Classes A contest winning F1Q 'Quiet' model by Ian Kaynes.
Part Four - In previous instalments Mike Evatt covered the main Glider, Rubber and IC Power classes in outdoor Free Flight. For this last article he introduces those classes which don't directly fit into these groupings.
Rules, rules and still more rules… of HLG is the magnet steered F1E. This difficult for the rule makers to keep Models Powered by Hand, latter class is hand launched from high pace with developments in motor and Catapult, Electricity, and Carbon ground and maintains its course upwind battery technologies. The most recent Dioxide! by a magnet steered forward fin. F1E has class is E36 which originated in the In the glider category, we have Hand been quite popular in Eastern Europe USA and was lately rebadged as F1S Launched Gliders (HLGs) which includes since the 1950's although recently it has almost unchanged by the FAI. It is fast the traditional chuck glider, the more become more widespread and more becoming a popular class with beginners recent 'discus' launched glider and the sophisticated. Although most still use and experts alike. less physically demanding 'Catapult' magnets for steering there is increased Finally, there are a couple of classes Launched Glider (CLG). experimentation with electronic for models driven by CO2. These motors However perhaps the top of the range compasses and electronic timers with were powered by the metered release of features such as rudder timing, radio CO2 from a tank previously filled from a dethermalization and bunt assist launch. 'Sparklets' bulb. Twenty years ago, there Although Electric Powered models were a number of manufacturers like have also been around for a long time Telco (UK), Brown (USA) and Gasparin it has been comparatively recently that (Czech). Sadly, these all had stopped the classes have become widespread production by the early 2000's although and popular for competition. It could be there is still a thriving second-hand said that the introduction of brushless market on eBay. Both of the CO2 classes motors and LiPo batteries was a are similar and give sedate long-run big game changer. It has been quite climbs.
A plan of Ivan Treger's 2008 Euro Champs winning F1E magnet steered model.
■ F1E GLIDERS WITH AUTOMATIC STEERING stopping the motor if it is still running. Any malfunction or Model aircraft not provided with a propulsion device and unintended operation of these functions is entirely at the risk of in which lift is generated by aerodynamic forces acting on the competitor. surfaces that remain fixed in flight, except for changes of This class is something of a dinosaur but it has its adherents. incidence. Variable geometry or area is not allowed. It is very sedate class to fly and suffers in that no one appears The glider can be equipped with a steering device, which to be manufacturing motors these days. However, many pre- may use a direction sensor and measurement of flight time. The owned motors are available on-line. steering device must not use any measurement of geographical location and must not be controlled remotely during the flight. ■ F1Q ELECTRIC POWER MODEL AIRCRAFT Model aircraft which is powered by (an) electric motor(s) Characteristics of F1E Model and in which lift is generated by aerodynamic forces acting Maximum surface area (St) .........................................150 dm2 on surfaces remaining fixed in flight, except for changes of Maximum loading ........................................................100 g/dm2 incidence. Models with variable area (e.g. folding wings) are not Maximum flying weight ............................................... 5 kg permitted.
F1E models may use radio control only for irreversible actions Characteristics of F1Q Model to control dethermalisation of the model. Any malfunction or Nickel Metal Hydride (NiMH) and Lithium (Li) batteries can unintended operation of these functions is entirely at the risk of be used. the competitor. External Battery packs are required to have a safety tether to This is an interesting class which appears to be gaining the fuselage. popularity. This is possibly because it does not need large Safety locks must be used to prevent unintentional restarting relatively flat areas required by most other disciplines. The of motor(s) after motor(s) have been stopped. rather generous area and weight rules rarely cause problems The motor run time will be determined by a maximum as most models are much smaller and lighter although a energy amount. In addition, motor runs of over 40 seconds significant amount of ballast is sometimes used to aid up-wind are regarded as overruns. The energy budget of each model is penetration. 3 joules per gram of the total weight (2017 rules). For energy Although a hand-launched class, the advent of bunt launches calculations, weight exceeding 500 grams is to be ignored. and GPS aided recovery seemed to have breathed new life into Models must have provision for connecting a Static Energy the discipline. Test (SET) device between the battery and the model's system. Energy limitation will be by an energy limiter or by a motor run ■ F1K MODEL AIRCRAFT WITH CO2 MOTORS limit related to measured power. For models with energy limiters. The allowed energy amount Definition starts to be calculated with the release of the start button and A model aircraft which is powered by CO2 gas motor and finishes when the ESC has stopped supplying energy to the in which lift is generated by the aerodynamic forces acting motor. on surfaces remaining fixed in flight, except for changes of For models without energy limiters the motor run will be incidence. Variable geometry or area is not allowed. controlled by a timer. The motor run is calculated as the allowed energy divided by the measured power and rounded Characteristics down to the nearest whole second below. Minimum weight (without CO2) ...................................... 75 g F1Q models may use radio control only for irreversible Maximum surface area (St) .........................................12 dm2 actions to control dethermalisation of the model. This may Maximum volume of the CO2 tank(s) ............2 cm (connecting include stopping the motor if it is still running. Any malfunction tubes count only if their outer diameter is over 2 mm). or unintended operation of these functions is entirely at the risk of the competitor. F1K models may use radio control only for irreversible actions I have précised this section as it is very detailed. For to control dethermalisation of the model. This may include the complete picture please consult the original FAI class
Peter Buchwald with his very fast F1S 'Small' Electric model.
Pascal Ceres flies a fine F1S.
■ BMFA Electric A BMFA Electric Power model Maximum weight of batteries in the capable hands of Trevor Ni Based..................................................................... 120 grams Grey. Li based........................................................................ 90 grams
■ E36 Electric
Model specification Maximum projected wing span................................. 36 inches Minimum total weight (ready to fly) ................. 120 g (4.24 oz) Maximum cells permitted...... Lithium - 2 cells; Nickel - 6 cells
A pristine BMFA CO2 powered model by John Ellison.
■ E.30 Electric competitor must launch the glider themselves with the catapult held in one hand and the glider in the other. Model Specification A good class for those lacking the shoulder power for HLG Maximum projected span ..........................................30 inches although a little more difficult to trim. Maximum overall length ............................................30 inches Maximum propeller diameter ........................ .............6 inches A Young Persons Guide… Minimum weight........................................................100 Grams These class specifications are somewhat of a mixed bag but Maximum battery size................3 x 50 mAh Nickel based cells provide a number of possibilities for fun and competition flying. or................................................. 1 x 70 mAh Lithium based cell Hand Launched Gliders and Catapult Launched Gliders are still a good introduction to aeromodelling and model Models shall have no moving surfaces other than for DT. aeronautics. They can teach a great deal about model The Maximum motor run from launch of the model shall be trimming. Balsawood models tend to be superior to their foam 60 seconds. counterparts. F1E slope soaring is fascinating class that has many This the 'electric' version of P.30 still has some followers but international competitions and is becoming more popular and has been rather overtaken by F1S/E36. technically sophisticated. Probably the largest models in the free flight portfolio. Combined Electric Class Contests The Electric Classes offer a good deal of the fun of flying an Combined Classes are a way of making the most of a flying IC Power model, but with much less noise and cleaner hands. site and the competition organisation. A Combined Electric E36/F1S is a very good starting point for anyone wanting to event might include a combination of three classes: F1Q, BMFA make a start in Electric Power positioned as it is between the Electric and E36 Electric. smaller E30 and the more technically advanced BMFA Electric When E36 models are flown in Combined Electric contests and F1Q classes. the motor run will be 15 seconds for all flights including any The CO2 classes are interesting, quite difficult to fly in windy fly-off. weather and rather reliant on pre-owned motors. I hope that this series of articles has served to unravel some ■ BMFA CO2 Duration of the mysteries of the outdoor free flight classes and has The combined capacity of the Carbon Dioxide tank and piping inspired some at least to try new aeromodelling challenges. system shall not be greater than 3.25 cm 3. Remember this is a highly-abridged version of the rules which Very similar to the FAI F1K class but with a larger tank and no focusses on the model specifications and hardly touches on other restrictions. the operational rules of competition flying. However, full details may be found on the FAI and BMFA websites listed below. ● ■ BMFA Hand Launched Glider The glider must be launched by hand without mechanical aids. The launch must be from within a 'box' 25 m. square References designated by the CD. All flights made within this box must be recorded as counting i.e. official flights. FAI International Regulations A delightfully simple specification embracing the simple www.fai.org 'Chuck Glider' to the usually larger 'Discus launched' model. BMFA UK Domestic Regulations www.bmfa.org ■ BMFA Catapult Glider Belair Traditional Kits, Laser Cut The glider must be launched by means of a catapult, powered www.belairkits.com only by rubber. The maximum weight of rubber allowed is 2 grams and Mike Woodhouse Plans and materials etc. www.freeflightsupplies.co.uk can be made up into any number of strands of any width and may be attached to a handle no longer than 6 inches. The Super Pearl E36 Plans and information www.pearlfreeflight.com 53
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For Old Times' Sake A look at pioneering models and modellers by Don Howie.
Interesting Models and Engines flown by Chris Birch (N.S.W.) and won throttle, finished with cream vintage This is a combination of models taken the inaugural David Owen free flight Solartex and red trim. The model was in 2015 at Middle Wallop S.A.M. 1066 trophy, presented by his wife Celia and flown from the RC area and used 3 Champs and recent photos taken son Sam. channels (rudder, elevator, motor). in Australia. The heading photo is Mike Phillips always has a variety Another model of note by Mike was a 42 inch span FF 'Apex', climbing of interesting models and he is shown the 48 inch span 'Diamond Demon', away at the August 2016 Oily Hand with his 64 inch span 'Alpha Corsair'. a 1940 kit by Consolidated Model Weekend, at Cowra M.F.C. in New This 1938 Joe Beshar design from Engineering , New York. The most South Wales, Australia. The model was the U.S.A. has a P.A.W. 19 diesel with interesting bit was the 1947 Clan .8cc
Rare and recent Polednik 1.25cc 4-stroke diesel in small 'Scram' Brian Martin with his 64 inch span T.D. Coupe (a 1936 design) at by Mike Phillips. Middle Wallop.
replica diesel made by Derek Collin, who Brian Martin from Cornwall is another balsa parts. The Falcon series from 1962 must be the outstanding maker of replica great vintage modeller, who builds a lot used two inserted spars in the wings and engines in the U.K. at the present time. of great designs. His 64 inch span 'T.D. one in the tailplane. The original Clan 0.8cc was made by Coupe' is a Dykzeul Design, published The 37 inch span 'Jr. Falcon' is shown Clan Models Ltd., 24 First Ave., Glasgow in Model Airplane News, October 1936. and was released in 1963 for the Cox and used a movable eccentric crankshaft The original would have used a 6cc Baby .049 reed valve engines and single bearing (note the arm) for compression Cyclone spark engine, but Brian has channel radio, that by then had a low adjustment. Only a small number were fitted an E.D. Comp. Special 2cc diesel voltage transistor receiver and used produced in 1947 and they soon revised for power in this interesting FF design. an escapement fitted in the fuselage, the design for the far better known Clan It uses Diatex full size aircraft covering near the trailing edge of the wing. The 0.9cc engine with a conventional on the wings and fuselage with Spectre leading and trailing edges of the wing contra piston. orange paint trim. were shaped and notched for the ribs, The most intriguing small diesel in Carl Goldberg liked inserted spars, the spars slid in easily and the wing recent times is the Polednik 1.25cc starting with the Comet Zipper pylon took minutes to build. My first 4-channel four-stroke made in the Czech Republic. model from 1939 which used up to multi proportional model in 1968 was Flitehook imported a small number of four spars to make an uninterrupted a 69 inch span 'Sr. Falcon' for the new these expensive engines several years surface for the Goldberg G-5 airfoil; this Taipan 61 RC Glo engine, using the same ago. I had previously seen one running was mentioned in a recent article by construction. at the U.S. S.A.M. Champs about 10 John O'Donnell. The Goldberg designs The 'Jr. Falcon' shown was built years ago, but Mike Phillips' is the first were quite difficult to build and the kits about 1965 and the wing was recently one I have seen flown in a model. The included print wood, which involved re-covered with Chinese silk. A servo small Scram has a single channel rudder tedious cutting of balsa. When he started is mounted vertically and connected to control, as one would not like to lose Carl Goldberg Models Inc. in 1956, Carl the original balsa control rod to rotate this engine. made his designs simpler with die-cut like the original escapement with Futaba
Jr. Falcon with Cox .049 reed valve glo, top single channel model by Carl Rear of 37 inch span Jr. Falcon shows round plug in fuselage (in front of L.E.) for Goldberg Models Inc. winding rubber motor for the escapement, and original rudder control linkage.
single channel radio. I fly the model each sports flying using the smaller engines Dislers in April 2016, AeroModeller. year at the Constellation Club's retro day. up to 1.5cc capacity, but flies fine with The model was covered with Aerospan engines like the Mills .75 or D-C Merlin. polyester tissue and the blue and red Apex The plan is available on the Outerzone colour and silver trim on the wings This was the model featured at the Oily website at www.outerzone.co.uk finished it nicely. Hand Weekend in August 2016, with 23 The simple box fuselage is easy to examples of different sizes (free flight construct and the three square spars in Mite .099 Diesel and radio assist) taking part. They used the top and bottom of the wing make it Being among the very first American diesel engines from .25cc to 1cc and the strong and warp proof. The tailplane has diesels, I think the Mite diesel engine models did fly very well. One gets the geodetic construction to keep it free of merits testing in my articles. It was impression that O.F.W. (Peter) Fisher may warps and the three fins give it stability designed by Howard Manderville. have flown in a Lockheed Constellation under power, when flying with a wide left Possibly based on the French Jide airliner about 1957, perhaps across turn. The nose seems very solid and the 8 fixed compression diesel of 1.7cc the Atlantic, as he was then inspired to model should have a long life. capacity, made in a suburban Paris design a free flight model with three fins. I was impressed with the 82% version cottage. A substantial number of these Peter Fisher deigned the 'Apex' for by Peter Lloyd, using one of the .44cc were sold to U.S. servicemen during late Performance Kits at 42 inch span for PAL Pesky diesels, as tested by Maris 1944 and 1945.
PAL Pesky .44cc diesel in 82% - a great sports diesel Original Mite .099 fixed head diesel, made in Mite diesel running at the home of Bill Britcher, - in FF 'Apex', a 1957 Performance Kits design. Brooklyn, New York, in 1947. separate fuel tank used.
T he subject of Supercaps for use in were to be wealthy, who would get the place of batteries has been covered work done? by Gareth Evans (AM No.949, June In the 'Supercool Way', the axioms are much 2016) and Duncan Pepper (AM more fun, such as "act first, think afterwards", No. 955, December 2016). While "leap before you look", and most importantly, excellent and informative, these articles lack the "ignore the advice of the experts". muddle and confusion which is ever-present in So the works of Evans and Pepper were the 'Supercool Way'. nothing short of a challenge to my cupidity. You see, there are societies where confused, Among my impressions were the following: bewildered and downright insane individuals are held in high esteem, to the point of their ● The models must be ridiculously light, made being leaders. These societies are called of old styrofoam coffee cups and flown nearly Duncan Pepper used the twin 'parliamentary democracies'. Their economic always indoors. KP00 motor unit geared to 4.75:1 model is called 'capitalism', wherein large ● The Supercaps charge almost which is available from KP Aero at www.kpaero.com numbers of poor people are needed to provide instantaneously. comfort for the wealthy. After all, if everyone ● They deliver a high current and can be
matched to cheap DC motors. pot would regulate the rate of charge/ the motors sprang limply into life as ● They produce their power at 2.7 volts discharge, and some banana connectors though blown by the wind. This was not but can be connected in series to get led to the twin DC motors I had exhumed going well. higher voltages. from a recently dead (murdered) flying toy Now with things not following the ● Two motors are better than one. robot. These latter motors, complete with script, I realised I needed to see what was ● Gutless little 20 Farad caps are the way their rotors, I gave their own board, where happening. In the good-old government to go. a cunningly-wired dual-throw, dual-pole funded days, I used systems voltmeters ● Suitable DC (brush) motors are to switch could connect the motors in either on the IEEE 488 data bus. This data bus be had. series, parallel or not at all. allowed the voltmeter readings to be Now here is the design philosophy. By displayed graphically on my computer None of this was of use to impetuous placing four of the Supercaps in series, screen, as volts versus time. You would me. I crush foam coffee cups in my bare with the rotary switch selecting them in have thought that in 2016, 40 years hands, instant charge is too slow for me, series of one, two, three or even four, I later, in the age of WiFi, you could have I want smoke coming out of the motors, could get voltages to the motors of 2.7, picked these up for $10 in the local but mostly, I want to control the power 5.4, 8.1 or 10.8. Now in the flying robot, 'Electronicery', but no. flow using an ESC (Electronic speed the motors were connected to each other So I had to resurrect my MaxiMite Geoff Controller). So it was onto the internet in series, using a 3.7 volt LiPo, speed Graham kit-build computer, which has 10 where I found I could buy six 120 Farad control being achieved by chopping up analog inputs. With the voltage across the Supercaps ready to go, mounted on a the DC voltage into pulses of varying cap(s) now being read into the computer board, for zilch dollars. length. With the un-chopped voltages on every 400 ms, I could plot the voltage on the caps as listed above, I should surely the screen and hopefully track down my Profound Idiocy be able to get some smoke signals from gremlins. That was where my studied ignorance the motors. No way. Nothing on the screen made started to pay off. I couldn't get the caps However, rather than toast the motors sense. After sleeping on these problems off the board. Seems that these days too soon in the testing phase, the 1K pot for a few nights, it occurred to me that I you need an oxy-acetylene torch to melt was there to limit both the charge and hadn't tested the caps before I put them solder, the lead content being decreased discharge rates of the caps. Then some on the board. After all, it was strange that to stop global warming. Fortunately I multimeters were hung off to monitor the they came already soldered into their own have a variable-power soldering iron: they volts off the power supply and on the board, complete with SMD's. Well, three came off with more trickery than heat. caps; also the current flowing into the of them simply would not charge, and the Next I needed a circuit with a power motors. The power supply had its own other 3 were leaky. None the less, you supply, switches, some multimeters, a current indicator. have to go with what you have got. variable resistance (1K potentiometer, or With Ohms law the governing concern, 'pot'), and a rotary switch. I picked up no inductors, IC's, transistors or other Results at Last a 30V, 3A power supply which was on confusing devices, how could I go wrong? With one-only working (and leaky) cap special at $100, and the rather expensive mounted on the board, I was able to rotary switch ($16) with 12 positions, Testing, Testing… observe the charging characteristic for when I only needed 4. All these items, With everything connected, expecting to a 2.7 volt 120 Farad Supercap, weight including the 4 caps plus some test see the rotors whiz around, I switched 14g. Now get this clear. Supercaps are points and switches were thrown into a the power on. Nothing. Not even smoke. not like the regular electrolytic caps. The hat, shuffled around and soldered as they That's where 240 volts are more fun. You Supercap can hold a charge five orders came out, onto a ready-tracked PC board. don't just get smoke, you get a loud bang of magnitude greater than your regular In theory, I could now throw switches as the hook-up wire vaporises. Careful electrolytics. That is enormous. The first which would allow charge/dis-charge/ scrutiny of the mother board revealed thing I found was that this Supercap did open circuit of any selection from four that the switch mountings were shorting NOT charge rapidly, did NOT discharge serially-connected Supercaps. The across the PCB tracks. With that fixed, rapidly and leaked charge away
profusely. circuit. This made the situation worse! never make smoke! Switching from series, At this point I gave up on these internet Unbelievably, the resistance of the shunt as used in the robot, to parallel motor caps, going instead to my local supplier was 6 ohms! This was a commercial item, connection, I was rewarded with another for three 100 Farad/2.7 volt items. but not a very good one. The crocodile jump in rotor speed. Mounting just one, I was rewarded to find clips at each end were secured to the For test flying a model, a pot of lower the charging rate was OK, the leakage wire lead by crimping, the crimp including minimum resistance would be a good was minimal , and the rotors at last some of the wire insulation! With the feature, limiting the power burst for initial started to spin in a healthy way. But not connections remade using good old flights. However, a better approach with nearly healthy enough. There were still solder, I was rewarded with a good RPM radio assist/servo-tester is to use an ESC problems to sort out. increase in the rotors. as a throttle: for this reason I chose the At the time of laying out my test circuit, On a roll now, I re-read Pepper's article, option of capacitors in series, as many I had not appreciated just how tricky it is wherein he connected twin motors in ESC's won't work off 2.7 volts. The to draw charge out of the Supercaps. If parallel and also doubled the capacitors. voltage output of capacitors in series is you want high power, you have to draw This seemed a bit bizarre, until I realised just the sum of the voltages on each cap. a high current. It is true that Supercaps that this trick lowered the resistance The little robot motors ran well for me can be discharged rapidly, but not in of the motors. The resistance of each up to 7 volts. I hesitated going to higher the circuit I had built. The 1K pot I had motor was about 1 ohm. Connected in voltages to preserve the motors for more installed for controlling the discharge rate series, the total resistance of the motors tests. Usually my tests-to-destruction worked alright, but I soon found that the was 2 ohms. But connected in parallel, occur earlier in the proceedings, but with lowest resistance available from the pot the resistance was only 1 ohm. It at first all the problems so far I was feeling a little was 2.8 ohms. This was way too much, seemed that bothering with such low cautious. even though it was the smallest resistance values of resistance was a nonsense, but I have ever used. the facts proved otherwise. Weird Charging The trick with getting a good flow of I cunningly connected the motors to a Now I have been skirting around the energy from the Supercap into the motors double-pole, double-throw (DPDT) switch. charging problem. Clearly I wanted to is to have a very low ohmic resistance This gave me 3 settings, series, parallel use the caps in series to give the rotors in the circuit, so I placed a shunt across and open circuit, all from the one device. a good spin. But charging the caps the pot to remove its resistance from the Incidentally, I don't like open circuits, they in series can be fraught. So, like the motors, I arranged two caps (giving a nominal 200 Farads!) in like manner to the motors: i.e., a flick of the switch changed the connection of the caps from series to parallel and vice-versa. This allowed for charging the caps in parallel, then switching to series for flight. Why bother? Why not charge in series? Well there are two answers to that. Firstly, and again rather weirdly, if you charge in parallel (at 2.7 volts) you can store more charge in the caps. That is desirable. But secondly, if you charge in series (at say 5.4 volts) you can damage the caps. Recall that these Supercaps are rated at only 2.7 volts. That is if you put more than 2.7 volts on one of them, they can be damaged. This is quite unlike electrolytic caps which can in some cases be rated at a 100 volts or more. Imagine you put 5.4 volts across two Supercaps in series. Each cap will have Rather busy screen shot generated by the MaxiMite computer to log the readings. Starting at zero seconds, the caps, connected in parallel, charge linearly as the power supply is in constant-current mode. 2.7 Volts across it, no harm done. But The curve following on after 60 seconds shows charging with power supply in constant-voltage mode, in this not all caps are equal. If one charges case 1.3 volts. Charging at 2.7 volts with parallel connection is permissible. At 200 seconds, charging ceases and the caps are switched to series to give peak power. The energy stored faster than the other, then it will have in the caps varies with the square of the voltage. Upper curve is the voltage across both caps. more than 2.7 volts across it and it will At 250 seconds, the motors, connected in parallel fire up, drawing current from the caps. Voltage drops until 300 seconds when the motors are switched off. At 370 seconds the caps are discharged back to zero volts. suffer damage. So, if for no other reason,
Power to Burn I was now in a good position. Circuit resistance had been minimised and it Silverlit (www.silverlit.com) produce many small twin counter-rotating RC helicopters which could be was time to run the motors at 2.6 volts. suitable for Supercap experiments. Recall that these rotors from off the flying robot were on long shafts, just as for the toy helicopters. In other words, this was whereas 2.7 volts (yielding 5.4 volts in ● The 100 Farad Supercaps did not a pretty rickety arrangement for a system series) would have provided a factor of charge rapidly, nor linearly with voltage, of co-axial, contra rotating propellers. four more charge to be stored. However, but we are only talking a minute or so. Such was the power now being the poor old robot shaft mechanism They should be charged in parallel then delivered by the motors, the rotors would have disintegrated. switched to series for flight. The problem wobbled badly. I replaced the rotors I am now convinced the system as was my inadequate power supply. A pack with a couple of props from a small, described should be more than enough of nickel metal-hydride batteries would be recently dead, drone; this also permitted to fly a reasonable-sized outdoor FF, such the way to go for charging. shortening the drive shafts. Testing as Tomboy or Mam'selle. However, the ● High current is available, provided that was now possible to proceed: see the co-axial counter-rotating shafts really the ohmic resistance of the whole system accompanying photos and captions. need some engineering, in the form of is low, of the order of two or less ohms all- Using only a 1.3 Volt charging setting, ball race supports. The friction losses up. Connecting two motors in parallel is batteries in parallel, motors in series gave in the existing system must have been very effective in this respect. 1200 RPM at 0.12 amps. Motors switched high. Also the drone rotors were pretty ● Connecting multiple caps in series is to parallel gave 1400 RPM at 0.32 amps. hopeless for use as tractors, the blade valid, enabling both longer motor runs With batteries switched to series, giving angle being very low, with consequent and the use of an ESC for radio assist 2.6 Volts, motors in series gave 1000 high profile losses. throttle of servo-tester power setting. RPM at 0.16 amps. Switching motors to ● Connecting multiple motors in parallel parallel, RPM was 2900 at 0.58 amps. The Re'Cap' increases the power output considerably. length of motor run in the latter case gave To return now to my impressions of ● 20 Farads are useful for low power these figures. Starting at 2600 RPM, 0.6 Evans and Pepper's work, I find: indoor, but 10 times that capacity is amps went to 2100 RPM, 0.48 amps after the future. 50 seconds. ● There is considerable power available ● The tiny brush motors in toy helicopters These figures do not represent the from 100 Farad caps for non-indoor work. and their derivatives are a good way to highest possible figures. The battery I can speculate that Mam'selle would be go. I have hammered mine at 7 volts and charge was at only 1.3 Volts per cell, nicely powered. still got no smoke. Must try harder! ●
AeroPost Do let us know your thoughts on AeroModeller and aeromodelling in general. We're happy to receive post to the Doolittle Media office address, or emails to editor@ aeromodeller.com – all are read although you may not get a reply. Featured letters may be edited. Regards, Andrew Boddington
INDOOR BYRACE reaching an altitude of at least 3 feet! It was during this 4 second flight that it was clear the rotors were not rotoring, it was flying using the 'wing' (the support for the rotors) for some lift. Flight 4 : Hmmm, thinks, maybe it is not getting a steep enough Hi Andrew, climb angle to the wind to get the rotors to spin, let's try a lot of up Having read your article about twin rotor elevator on take-off (did I mention I went wild and fitted both rudder autogyros I decided to build one for indoor flying. and elevator!) Once again it raced across the ground at impressive Using Depron I made one at approximately 2/3 scale of the Byrace plan for speed. It leapt into the air and climbed steeply to about 50 feet the rotors whirling. They were obviously providing lift like they should so electric power and three channel control. It came out at 32 grm ready to fly I thought I'd better turn to make sure it stayed in the field. The turn and to my (and fellow flyers) surprise it flew. started ok but rapidly tightened into a spiral dive and ended abruptly Regards, Chris Grant. at ground level with 2 broken rotor blades. I repaired the rotors, just superglued them back to flat and doped a Hi Chris, piece of tissue over the join. It was clearly very sensitive to rudder I was hoping somebody would have a go at a Depron variation of the Byrace. movement so I reduced it by about half and went back to the field. Having seen many twin rotor designs fly I'm not surprised it was a success as Subsequent flights were better as I was ready with a bootful of right it is stable and forgiving configuration once set up. rudder as it went off. Fantastic! It was great, it climbed to at least 100 feet and once properly trimmed I could steer right and left. Last test Regards, Andrew was engine cut… would it auto-rotate? YES! The rotors whirled on and it came down fast but under some control over direction! Most pleasant to fly now, can't wait to get up again and try a loop or a roll? Go build one and join the expanding group - a friend has nearly finished his.
Hi Mike, Glad to hear you're having fun with the Byrace and I'm impressed you are getting ROGs. Do make sure the blade hubs are lubricated and spin freely. Regards, Andrew
Mike Minty used an elevator push rod of 22 swg wire in a plastic Chris Grant's smaller autogyro uses Depron sleeve on his 2 channel Byrace. with carbon rods for strengthening.
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reducing the number of molecules in the balloon "Building a Model Aeroplane". Sadly I've been and hence it gets lighter and floats. unable to find a decent picture of his Jetex design Kids enjoy flying them, realise how they go up but I can tell you it was 20 inch span and came and come down as the inside air cools, and great complete with a Jetex 50 motor for the princely fun is had by trying to stand under a descending sum of seven shillings and eight pence and flew balloon and get your head inside - Only to be told very well. off, as it is a plastic bag and one must not put your So when Roy Lever (Powermax) brought out head inside a plastic bag. But it is good fun and a a "modern Jetex" in the 1980s I bought one but slim young lady completely disappeared inside a I could never make it work properly. Recently I balloon the other day!" came up with an idea which needs that sort of Well that puts my mind somewhat at rest then. power and thought of using a Rapier or similar I've also heard from a number of people about power unit – only to find that they are unobtainable bigger 'scale' model hot air balloons including today. However, as I see similar items being used Richard Gahan and Andy Marshall of AM Balloons, at most of the Old Warden events, someone must Rocket powered model at Peterborough see www.amballoons.com be doing something! Is there a secret Rapier Flying Aces. Andy said supplier who, with the right "secret handshake" "Technology wise most of what we do mimics will sell me what I need? Or is it just that a few man carrying balloons, high tenacity rip stop sensible people realising that Rapiers would soon nylon, flame retardant nomex, propane fuel. disappear stocked up? Or, the final possibility – Is Some people make and fly woven baskets, others there another mini rocket motor known only to the build 'cloudhopper' air chairs often quite novel few? I don't know, so it's over to you dear readers constructions to tell me! (I'm sure the readers won't disappoint possibly the most challenging projects are to you – the Editor.) build small; 6m3 I think is the smallest working Finally, please send your comments, model I've seen in the UK, though I've heard of anecdotes, complaints and suggestions to me people flying balloons measured in litres. The UKs at email@example.com or via the editorial largest is 110m3. offices by snail mail. ● The balloons cool quickly requiring piloting skill to predict the fall from equilibrium, and adjust, though we use no vent systems as the pressure is By Chris Ottewell not sufficient to make them function in the same Jetex 50 Rocket Motor
IN STOCK NOW! 0.25cc TBR TINY TIGER
COMING SOON! 0.35cc TBR MINI ETA 15
Our book the "Olivers and a Tiger" soft back still available at £25 plus £5 p&p (UK only). Always wanting model cars, engines and collections.