1/18 scale Wallis WA-116 Agile autogyro scratchbuild model

The following construction is a tribute to RAF Wing Commander Kenneth Horatio Wallis DSO MBE CEng FRAeS PhD, a pioneer gyrocopter aviator, who passed away early on Sunday morning, September 1st 2013. Ken was 97 years old. During the WWII, Wallis served in the Royal Air Force as Westland Lysander and Wellington pilot and flew 28 bomber missions over Germany. After the War, he flew the massive Convair B-36 and later involved in research and development, before retiring in 1964. He later became one of the leading exponents of autogyros and earned 34 world records, still holding eight of them at the time of his death. He was an inspiration to us all and we shall greatly miss him. A local hero and a national treasure.





He was born on the 26th April 1916, at Ely in Cambridgeshire. With his father and uncle having built an aeroplane in 1908 to fly the channel in a competition that was eventually won by Louis Bleriot, Ken Wallis acquired an interest in practical mechanics at an early age and by the time he was eleven years old had built his own motorcycle. He eventually turned his attention to aviation following a flying demonstration he watched in 1936 of the Henri Mignet HM-14 Flying Flea / Pou Du Ciel.





Ken will be greatly missed by the Flixton museum members. He was a frequent visitor, generous fundraiser and a great ambassador. In addition to the numerous professional institutions who welcomed Ken as a member and the vast number of clubs who regarded him with great respect and fondness, many ordinary people will also feel a loss in one way or another. Even a short chat with him left the individual feeling that it was something special and his warmth made them feel that he would remember them! Ken was recognised wherever he went. Admirers would soon gather and he would usually produce a small clipboard from a pocket, to sign and give away autographed postcards of him flying the "Little Nellie". I am sure that many a childless adult has asked for a card to give to their “offspring”. Ken was inspirational, a great role model and possessed a rare old-world charm plus the impeccable manners of his age; all without a hint of grandeur. I am not alone in thinking that he was probably the grandfather figure we would all have liked to have had at some time. Norfolk was Ken’s home from 1963 and I venture to think he was appreciated by such a large part of its population that he was likely a close second to its most revered inhabitant: Horatio Nelson.

Goodbye Ken - our gyrocopter aviation hero and national treasure.

CHAPTER I - Little Nellie only lives twice

The autogyro differs from the helicopter in that it has a upwards thrusting propeller and a second prop to drive the forward. The gyro's upward's prop lifts air much the same as a glider. The autogyro's roots go back in 1921 when it was invented by Juan De la Cierva, when he was looking to develop a light and fast bomber for the Spanish military. Development continued over the years and during WWII both Germany and Japan built their own autogyro versions. Wallis Autogyros Ltd was founded in 1961 by RAF Wing Commander Kenneth Horatio Wallis and has produced an extremely wide range of special purpose autogyros. The Wallis WA-116 Agile created by Wallis runs on the same principles as that built by Cierva but it much smaller and more nimble. The first prototype, registered G-ARRT, was a single seater ultralight autogyro first flown on 2 August 1961 and being developed with different models over the years, with such uses as military training, police reconnaissance and survey work. It could lift twice its own weight, fly 210 km/h and rapidly climb to 4100 m, even though it weighed 110 kg. This aircraft could take off in 30 yards of space at a minimum speed of approximately 20 km/h. In 1962, five WA-116s were built by Beagle Aircraft at Shoreham, three of which were for evaluation by the British Army Air Corps.



In 1966, one of the Beagle built WA-116s, registered G-ARZB (nicknamed as “Little Nellie”), was modified for use in the 1967 James Bond film “You Only Live Twice”. Few Wallis autogyros have been operated privately, with nearly all of them being used for research and demonstration flying by Ken Wallis himself.





The Wallis WA-116 Agile was powered by a McCulloch Model 4318A four cylinder horizontally opposed air cooled engine, providing a top speed of 185 km/h and a range of 225 km. After building nine single seaters, the construction of a two seat variant the WA-116T was begun in 1969; Ken Wallis tested a four blade rotor and finally produced the WA-116F with which he won the closed circuit world record in 1974 in the 670.26 km category. Wallis autogyros have been powered by various types of engines, within the range 72 hp to 160 hp (the latter is used in the two seat Wallis WA-122) and have been employed for research programmes, including one promoted by Sperry Radar. In 1983 development of a production version, powered by a Weslake engine, was under way in association with Vinten Ltd. Intended primarily for paramilitary use, including policing and survey work, the definitive aircraft is due to be certificated in 1984. Ken Wallis, developed a number of improvements to the autogyro design, including the offset gimbal rotor head which gives the autogyro hands-off stability.



Technical data & general characteristics:

• Type designation: Wallis WA-116 Agile,
  
• Manufacturer: Wallis Autogyros Limited,
  
• Usage: Reconnaissance / recreational autogyro,
  
• Crew: 1 pilot,
  
• Year of first construction: 1961,
  
• Year of first flight: 1962,
  
• Country of production: United Kingdom,
  
• Length: 11 ft (3.38 m),
  
• Height: 6 ft 1 in (1.85 m),
  
• Rotor diameter: 20 ft 4 in (6.20 m),
  
• Empty weight: 255 lb (116 kg),
  
• Gross weight: 550 lb (249 kg),
  
• Maximum speed: 100 mph (161 km/h),
  
• Rate of climb: 1071 ft/min (5.44 m/s),
  
• Service ceiling: 10000 ft (3048 m),
  
• Range: 130 miles (209 km),
  
• Flight endurance: 2.5 hours with 58 lb fuel,
  
• Powerplant: 1 x Wallis McCulloch 4318A piston engine, 54 KW (72 hp).

CHAPTER II - Converting Mbytes into actual model parts

Before start building a new scale model, I always try to study as much as possible the object of construction. Any available technical manuals and detailed walkaround photos, always help during model building process. As previously described into my previous WIP (feel free to have a look on the 1/18 scale Instytut Szybownictwa IS-A Salamandra 53 scratchbuild model, already uploaded into the present forum), the plan is to design a CAD file and then print it, on a 3D replicator. This method, helps a lot and gives the opportunity to scratchbuild almost anything, under any scale, within only few minutes. The 3D printing technology introduction into scale modelling and free access to the average modeller is a great evolution in the hobby and a creative tool that helps us to build better and more realistic models. Certainly the new technologies and gadget tools in the hands of talented enthusiasts open new horizons and provide wide potentials on scale model building.



It took a couple of hours of CAD work on my laptop, to 3D design, scale into correct 1/18 size and then digitally cut the autogyro’s compartments into virtual pieces, having always in mind that the later printed parts, should perfectly fit and finally become a fine scale model. And voilà, we have a winner! A new Wallis WA-116 Agile autogyro virtual model, is ready to be forwarded to the 3D printer and become an actual object under 1/18 scale, within short time.





After building the 3D model and double check for possible mistakes, I saved it as a digital file and forward it on a 3D printer to start generating the individual parts of the autogyro scale model. Shortly thereafter, the printing proceeding outcome pleased me, while watching the Mbytes, magically converting into actual items. Once again, the 3D printing technology on scale modeler’s service. As seen in the following pictures, as soon as the produced parts were cleaned, I checked for broken parts & imperfections. The model now consists of only a few parts, found into basic frame sections. Some additional details such as supporting rods, control bars & wires etc made of styrene, will be later added.

CHAPTER III - Attempting to join the basic parts

As soon as the individual scale model’s parts were already produced, cleaned & dry fit tested, I had to assemble everything as one piece, without damaging the frame construction. The plan is to assemble all model’s parts first, sand if required and later apply paint and weathering effects as a final touch. During assembling process, everything was secured in place & glued with CA liquid adhesive superglue, which does bonds in only few seconds, reaches extremely strength at room temperature and it is suitable for materials such as wood, rubber, plastic, metal, ceramics, leather, marble, polyethylene, polypropylene, teflon etc. Some tiny gaps were filled with putty, applied with an old brush. As soon as the joints were securely glued with CA superglue and later filled with putty on tiny gaps, it was carefully sanded with nail files & sanding sponge block. When it looked OK to me, the whole model was sprayed over with Humbrol acrylic primer to spot any mistakes and placed into a box to wait the final paint applying.





After my sweetheart wife (aka “4-star General in home” & “family's financial director”) conducted a strict quality control and result evaluation, she smiled & proudly signaled green light for further building & painting. Each section was dry fit tested to ensure that anything can be combined together as one piece, the parts forwarded for assembly.

Hi Nick

I'm very sad to read of the passing of Ken Wallis. I'd missed this bad news - he was always something of a hero of mine too.

It's really interesting to see how you're using 3-D printing. None of the affordable commercial options I've looked into offer the resolution I'd need, but your shots look great. Where do you get the parts produced?

All the best

Rowan

The 3D files of this 1/18 scale Wallis WA-116 Agile autogyro and the previously presented 1/18 scale Instytucie Szybownictwa IS-A Salamandra 53 glider, made by using comercial CAD software and later printed on a home MakerBot Replicator. The only exception are the wings of the previously mentioned glider, due length (70cm from one wingtip to the other) had to be printed on an industrial printer.

Hi Nick

That's amazing - I've never seen the MakerBot able to work at the resolution I need. Of course, I work a heck of a lot smaller than 1:18, so that makes a difference.

All the best

Rowan

@ Rowan,

I believe that factor "printing detail" has nothing to do with factor "scale". The nowdays 3D printers are not perfect, but I think its all about the injecting matterial too. For example, if you use the most cheap resin matterial, yes parts might not have smooth surface and might need some extra finishing sanding work. On the other hand, if you use more sophisticated matterials like acrylic based polymers or special V-cured acrylic plastics that can print fine details, give a smooth, translucent & slightly shiny result, you ll be amazed. Using more sophisticated matterials and special acrylic based polymers, I have already 3D printed some of my future project parts and offered for a close look to few fellow scale modelers. I ensure you, that they did not believe their eyes with construction quality, scale accuracy and above all, the (lower than expected) production cost. Maybe its too early, but in a few years - much earlier than we all think - the 3D products quality will be excellent.





Each tool may become "useful" or "useless", "necessary" or "nonessential", depending on the hand that operates it. The point is that all modelers can now have access to a new World of CAD designing & 3D printing. If I was able to do it, that means that anybody can do it! If I learned how to design, improve, reconstruct & 3D print my own models, in any scale I like, you can also do it - possibly much better than me.

Hi again Nick

I think you should have a word with their marketing guys - the examples you've shown are far better than what they're using to demonstrate the technology.

All the best

Rowan

CHAPTER IV - Wool flock covered seat

While studing on Wallis autogyros photos, I noticed that Ken had covered the Wallis WA-122 G-BGGW passenger's seat with wool flock fiber stuff. To be honest, I 've never seen any of the Wallis WA-116 autogyros having seats covered with this way, but I thought it was a good idea to replicate under scale and maybe possible to have happened in real gyro.





Using a small amount of Milliput putty, I made a small ball, dust it with talcum powder and pressed it against the working bench with a roller until it becomes about 0.5mm thin. The use of talcum powder is necessary to avoid Milliput sticking on roller or fingers and get easier to handle without tearing to pieces. While Milliput putty was still soft, I cut it into shape and placed it on pilot's seat, to form into a right to scale blanket cover.











Then, seat covered with masking tape in such way to leave only the Milliput blanket area vissible. To recreate the seat cover, I used the #KF-00017 flocking powder product by KA Models, which is commonly used by scale car modelers to represent carpets. As you can see in the following photos, the flocking powder sprinkled through a sieve, over the Milliput blanket. When it looked OK to me, the powder secured in place, by airbrushing hairspray over the result.

CHAPTER V - Applying paint, wash & weather effects

Before dealing with this project, I had the impression that all Wallis autogyros, were all same - at least identical. The fact that each one of them is not a product of a factory assembling line but the result of custom hand work, shows that there are plenty of differences between them - obvious differences or just small details identified after careful observation. The autogyro represented here, is the s/n G-ARZA, one of the five first built WA-116s, typed as "Wallis WA-116/Mc Srs.1" (the “Mc” means McCulloch engine and the “Srs.1” goes for series 1). The three of these first five Wallis autogyros were produced on behalf of British Army Air Corps for further evaluation and had no cabin cover. After a brief military carreer, these three Wallis WA-116/Mc Srs.1 remodified, repainted and received new civilian callsign reguster. One of them, was destined to become very famous as "Little Nellie" after appearing in the 1967 James Bond film “You Only Live Twice” movie. Research based on the published files & info, shows that the serial numbers of these first built "Srs.1" are the following:

• G-ARRT was the first Beagle Aircraft built prototype, first flown on 2 August 1961 at Shoreham. Aerodynamic cabin cover added later.
  
• XR942 initially built on behalf of British Army Air Corps and later renamed to G-ARZA. Aerodynamic cabin cover & beacon lights on rudder fin added later.
  
• XR943 initially built on behalf of British Army Air Corps and later renamed to G-ARZB. Aerodynamic cabin cover & dummy rocket launchers added later to become the widely known 007 James Bond’s "Little Nellie".
  
• XR944 initially built on behalf of British Army Air Corps and later renamed to G-ATTB. Aerodynamic cabin cover and longer main rotor blades added later.
  
• G-AXAS was the last built "Wallis WA-116/Mc Srs.1" and was Ken's favorite, since he was usually demo flying with it at Reymerston Hall Dereham, UK until his last days. The tail rudder fin was replaced on 1986, by a Wallis WA-122 spare part.

My goal is to paint the scheme of the G-ARZA, dressed up with it's new civilian colours, as appeared at EGBK Sywell, UK during the PFA Rally, back in 1973. Keep in mind that the specific autogyro, was initially built for military use, registered as XR942 and painted dark olive with official British Army markings - as seen at EGKB Biggin Hill, UK during the Biggin Hill Air Fair, back in 1964.



Model parts were washed with liquid soap and warm water to disappear leaving oil traces, fingertips etc and prepared for painting process. When it comes to apply paint on a scale model, I usually have the following two available options:

• Paint the individual parts first and assemble the scale model later and
  
• Assemble the scale model parts first and paint the overall built model later.

Since I designed this 1/18 scale Wallis WA-116 Agile autogyro in such way to look like a kit instead of 3D printing it as a fully built model, the first option seemed as more appropriate and would certainly make my job much easier. After preparing the engine’s basic elements, connecting electric cables and oil or fuel lines, the aft part consists of the tail boom & rudder fin structure, the McCulloch 4318A engine and the transmission components etc painted by using fine brush. The front part consists of the cabin aerodynamic cover & flight controls, airbrushed with with Life Color LC01 Matt White FS37925 acrylic paint for exterior and Life Color LC02 Matt Black FS37038 for interior. The red stripe on aerodynamic cover and tail fin, painted with Life Color LC06 Matt Red FS31302.

To form a complete pilot’s seat, I used the “EP-0017 seatbelts” photoetched set by Crazy Modeler, under 1/20 scale. The seatbelts got paint with red color - although they looked like khaki color in B&W pictures of the actual gyro - so as to make sharp & nice looking contrast with the previously mentioned (into CHAPTER IV) wool flock blanket covered seat.







Some additional items, also designed from scratch and later 3D printed under 1/18 scale, such as fire extinguisher, 20 lt fuel canisters, wheel chocks and taxiway light unit, got also some paint & dirt effects. Maybe is not easily vissible, but there is also a bulb inside the blue cover of the taxiway light unit. Unfortunatelly, its hard to discern behind the dark blue glass





To replicate the G-ARZA callsign & Wallis logo on autogyro’s tail rudder and a few more written details on fire extinguisher & fuel canisters, I had to create some right-in-scale custom water slide decals. To do so, I used the A4 sized printable “Experts Choice Decal” film by BMF - Bare Metal Foil Co. The decal film is available in both clear and white one. The decal film can be printed on color inkjet printers, on LASER printers or a color photocopier to reproduce any digital image. Keep in mind that the inkjet decal film is intended for use with inkjet printers only. For photocopiers and LASER printers, the LASER decal film should be the best choice. After designing the images on Corel & rescaling on right dimensions, LASER printing the water slide decals on film and thereafter applying decals on model, I used a soft brush to apply a light coat of Microscale MicroSol to soften the decal and allow it to become part of the surface.





As soon as the water slide decals were dry, an acrylic gloss coat applied to seal the result so far. Once the acrylic gloss coat has cured, I tried to wash the paint by brushing artists grade oil paints with a broad, soft brush and spread the paint around until the desired colour density is achieved. At this point the oils would be workable for several hours. With a broad, soft, clean and completely dry paint brush, I draged over the oil paint, leaving dirt streaks. As the brush picked up the paint, I wiped it off on a clean, lint free cloth and continue process. “Lint free is the key phrase, as any speck of lint would adhere to the oil paint and destroy the finish. The beauty of this technique is that you can clean the oils off and try again if you goof up. I used a clean cloth and turpenoid paint thinner - not lacquer thinner - to wipe clean any mistakes and start over again. Some of the wash mixture is re-applied and the wash being wiped completely out of the narrow points.

CHAPTER VI - Concrete apron display base construction

I found nice idea to place the Wallis WA-116 Agile autogyro model on a display base, simulating a maintenance & refueling area with short grass sprouted between concrete slabs. My goal is to recreate a scene of an airfield apron area where pre-flight activities were done. An apron is any area for parking and maintenance.





I add some grams of plaster powder and few drops of water into a soft rubber cup to make the right mixture. Materials like plaster, start as a dry powder that is mixed with water to form a paste which liberates heat and then hardens. Plaster remains quite soft for few hours after drying and this characteristic make it suitable for the job.





Keep in mind that:

• Adding salt into wet plaster mixture, reduce the plaster's hardening time,
  
• Adding vinegar into wet plaster mixture, extend the plaster's hardening time.

When the first layer of thinned plaster applied on a clean surface, a flat glass were pushed against the plaster to form a flat basic strong cast. The basic idea, is to produce a totally flat cast and later add some detail or apply extra stuff where is needed. I left it few hours to get harden in order to be sure that the cast wouldn't break when I would try to cut it into desired shape. Meanwhile, I took the soft rubber cup which I used to make the plaster mixture, squized it to break the last hardened plaster left inside, so it would be easier for me to clean it afterwards and prepare it for any future mix. That's the reason this soft rubber cup were used for.





As soon as the plaster cast got harden, cut into shape and the concrete plaques were lined with a scriber, I used my airbrush to paint it. As I usually like to do, three different acrylic paint layers were applied on the plaster surface. First, mat black colour covered the area and then a light grey applied with airbrush, spraying in almost zero degrees angle, to let the darker areas between the concrete plaques remain naturally dark. The corner was paint with lighter grey & earth tones and as soon as the acrylic colours dried, I tried some drybrushing on selected spots using sand tones.







As for the vegetation that grew between the concrete slabs, I used some Heki static grass found at my local hobby shop. Heki, specializes mostly in train dioramas.





Water based white glue for wood, which becomes transparent when it dries, is just the right for the job. So, I opened a 500gr canister bought for 2€ only, pick a small quantity, add just few drops of water with a syringe into a small metal container to make the right mixture and finally I applied on the desired areas to be filled with grass & plants, using a wet brush. Because the mixture is enriched with water based glue, it is easy to correct possible mistakes.













As soon as the result was OK, I sprayed over with Humbrol enamel mat coat, to seal the paint and grass, so far. I left it overnight and as soon as the enamel mat coat dried, I add very few light & dust effects with chalk dust and pigments. For those who may say that the vegetation sprouted between the concrete slabs looks excessive for an active apron, think again. I 've seen European capital international airports, with jungle-like grasss on apron ground area.



From my local store, I bought a 20x30 cm shiny laminated wooden picture frame. The empty space, filled with 5 mm thick sheet of balsa wood. The plaster made ground, paint already, carefully moved on laminated wooden base and secured in place with silicon glue.

CHAPTER VII - Attempting the final scene setup

As soon as the individual scale model’s parts, fuel canisters, fire extinguisher, both main & push rotor blades were already painted & weathered, I had to conclude the final part. To assembly everything in one piece and setup the final scene. The autogyro, would be the first to be placed on the apron concrete ground display base. The model secured in place, by wedging the pins under the wheels into holes that had been already opened on plaster. Yes, that was the reason that the wheels had pins underneath! Later, the fire extinguisher & both fuel canisters secured on ground with hidden metal pins and glued with transparent silicon. Final details were added, such as headphones set, tire chocks on main LG wheels, rotor blades & locking bars, some extra dust & weathering effects on some areas, etc. As a last moment’s addition, an earthing cable also added to connect autogyro's frame with ground and discharge electricity while refueling process.







As soon as the result was OK for me, the scene sprayed over with Humbrol enamel mat coat, to seal the work so far and left it overnight to dry. The next day, I did a final inspection on result and set it up to shoot some pictures.

Wow, a super result, and very quick work too! What proportion of modelling time was in front of the computer doing the CAD?

CAD file and computer work (starting with an "empty screen"), took me about 30 hours. On the other hand, research and study on subject, took weeks - maybe months.

CHAPTER VIII - Epilogue & aknowledgments

Although I was planing to paint a fictional / anniversary scheme, possibly by adding the also fictional call sighn G-BYE (aka “GoodBYE”) on tail rudder as a farewell to RAF Wing Commander Kenneth Horatio Wallis, inventor of this little autogyro and pioneer aviator, who passed away only few weeks before writing these lines, I finally decide to present the G-ARZA. It’s the ex XR942, initially built as s/n B.201 "Srs.1" WA-116 by Beagle Aircraft at Shoreham, on behalf of British Army Air Corps and first flew on 10 May 1962. According to Ken Wallis himself, this is now preserved in Portugal - unknown location.



I ‘d like to share with you, a rare photograph. It takes us back to autumn of 1967, in Germany. The man at right, is the inventor of this little autogyro, RAF Wing Commander Ken Wallis who flew 28 bomber missions over Germany during WWII and later earned 34 World records. The other man (left) who is sitting inside the cockpit and trying the flight controls, is Luftwaffe General Adolf Galland, a true aviation legend, a WWII flying ace who survived throughout 705 combat missions and credited with 104 aerial victories against the Western Allies. Who could imagine that these two friends, were flying a few years before as deadly enemies, trying to kill each other.



I would like to express my special thanks to:

• The administration of the Norfolk & Suffolk aviation museum where Ken Wallis has been its President since 1976, for providing me the printed matterial, technical manual & blueprint diagrams for Wallis WA-116 autogyro.
  
• All fellow scale modelers, who have expressed their ideas through this forum and suggested solutions to technical issues encountered during this WIP.

Finally, thank you all for following this thread and I hope you enjoyed reading this article. I’ll meet you soon, on my next WIP.

Regards,
Nick