Friday, August 11, 2017
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RC Helicopters Come Of Age




The state-of-the-art in RC helicopters has progressed by leaps and bounds during the last 10 years. Today’s RC helicopter can perform amazing 3D stunts that leave spectators in awe. We have come a long way from the old days of flat-bottomairfoil wooden rotor blades and bent aluminum side frames. Let’s sit back and look at the evolution of RC helicopters by reviewing some of the interesting products that have been shown at the world famous Nuremberg Toy Fair in the last 10 years1999 to 2009. The Nuremberg Toy Fair in Germany is the world largest trade fair for the hobby industry. The show occupies 12 buildings (150,000 square feet) all linked to showcase toys, video games and hobby products. RC hobby products occupy two buildings. Since it is fairly expensive to rent a booth, companies display only their best new productsthe ones that will be introduced that year. The products shown are usually at the prototype stage, just released, or about to be released within six months or so. The show is open only to distributors, dealers and the press. About 70,000 trade visitors attended this year.
BIRTH OF THE .90 3D HELI
Graupner, one of the largest and the oldest hobby companies in the world celebrated their 70th anniversary in 2000. Wolfgang Simon, the chief designer and manager for Graupner Helicopter Products, can be credited with helping with the introduction of .90-size helicopter engines. Before 1999, the top of the line RC helicopters for F3C competition or 3D flying all used .60-size (0.60 ci piston displacement or 10cc) engines. Wolfgang experimented extensively by modifying an O.S. 91 FX airplane engine to convert it into a helicopter engine. O.S. and Thunder Tiger became the first engine companies to offer a .91 helicopter engine a year later. These .91 engines have the same external dimensions as .60-size engines and they fit in traditional .60-size helicopters. The only change required is to reduce the helicopter gear ratio by around 9-to-1 to 8-to-1. By 2003, the .60 class RC helicopters practically died over night because every pilot wants more power and to fly faster, hence the birth of the new .90-class, super-powerful 3D helicopter era.

In 2001 Graupner became one of the first companies to offer a complete, proven turbine engine powered RC helicopter kit together with engine for about $6,000 U.S.
The Graupner NH-90 model uses JetCat turbine engine and a true gear reduction transmission.

THE FIRST MICRO ELECTRICS
On the other extreme was the birth of micro electric helicopters 10 years ago. The Ikarus Piccolo was the first commercially successful micro electric helicopter that easily flies over four minutes on a single battery charge. The Piccolo was demonstrated to the public at the 1999 Nuremberg Fair. Norbert Gruntens, the owner of Ikarus, flew the prototype Piccolo inside his 10 ft by 10 ft display booth. He even landed it on a 12 inch wide glass table many times. On one occasion the glass was so slippery that the Piccolo sled off the glass table. But Norbert picked it up and flew it again; very impressive. Mr. Gruntjens, even gets on the European television twice a week to sell the Piccolo on the German equivalent of the QVC telemarketing TV show. He would fly the Piccolo in the TV studio in Munich and answer telephone callers on the TV show.

Mr. Tanaka of Hirobo demonstrates the Hirobo XRB Lama coaxial electric helicopter in 2001 at the Nuremberg Toy Fair. This is “the” coaxial electric model that started it all.
Two years later, MS Composit, a Czech Republic company unveiled their micro Hornet at the Fair, and their chief test pilot, Petr Novotny, hovered the Hornet inverted inside the MS Composit booth. These two models are the pioneers of micro electric helicopters. They helped increased the aura of mini electric RC helicopters worldwide and helped introduce many people to RC helicopter flying. Eventually, a whole new mini electric helicopter revolution was started, and the Shogun 400, T-Rex 450, mini Titan E325, and many, many mini electric helicopters were introduced. Now, the mini electric helicopter is one of the hottest niches in RC helicopters.
THE COAXIAL HELICOPTER
In 2001, behind the curtain at the Hirobo booth, Mr. Yamada of Hirobo and his test pilot did a demo of their new prototype contra rotating main rotor electric helicopter. This model had a 10-inch diameter main rotor disk and this was the first secret unveiling of the famous Hirobo XRB Lama coaxial micro electric RC helicopter. Contra-rotating helicopters do not require tail rotors and hence are more efficient. This ingenious model does not have collective pitch command. Vertical lift is varied by changing rotor rpm. Each rotor is powered by a separate electric motor. Rpm for the top and bottom rotors are varied differentially to control yaw. There are no Hiller control paddles. Cyclic control is achieved by a swashplate controlling the tilt of the main rotor only. There is a flybar connected to the top rotor. The top rotor can tilt and combined with the Bell stabilizing bar (a flybar with weights only) helps stabilize the helicopter in the longitudinal and lateral directions. At the show, the model was flown with a tethered cord that connects to a NiCd battery on the floor. Two years later Hirobo introduced a coaxial Lama that could fly for 10 minutes using an onboard 7.4 volt 2S Li-Po battery. Hirobo’s Lama coaxial electric helicopter revolutionized indoor flying. This coaxial design was unbelievably stable, even people who had never flown RC helicopters before could hover it confidently after 30 minutes
of practice. Coaxial helicopters were produced by more than 30 companies around the world in the years to come. Today, it is possible to buy a ready to fly coaxial electric RC helicopter at toy stores for well under $100. We have to thank Hirobo for introducing this new form of flying.
Frank Heinrich proudly display the first
collective pitch equipped Piccolo
helicopter from Ikarus in 2002.


Robbe is one of the two largest RC hobby companies in Europe. This was 2003 where Robbe displayed their .90-size scale BK-117 model and their electric Eolo helicopter.
THUNDER TIGER RAPTOR
Another history making helicopter design from 1999 to 2009 is the Thunder Tiger Raptor. It is undisputable that the Raptor series has been one of the most successful RC helicopter lines ever produced in the entire history of RC helicopters. 2008 celebrates the 10th anniversary of the Raptor. The first Raptor 30 was demonstrated at the 1997 IRCHA Jamboree in Ohio. After the first batch
of Raptor 30s arrived in the USA in 1998, the modelers immediately discovered the Raptor 30 had amazing stability, yet the handling was so forgiving and predictable that it became a perfectly affordable and rugged 3D trainer. The Raptor 30 helped graduate many 3D pilots around the world.

2003 MS Composit introduced the first electric powered tandem helicopter. It is a scale CH-46.

Loyal followers of the Raptor 30 anxiously awaited the introduction of a Raptor 60. At the 2001 Nuremberg Fair, Thunder Tiger unveiled their new Raptor 60 and it received much attention. Magazine editors had their cameras clicking away continuously. In less than a month since its introduction in the USA in 2001, more than 1,000 Raptor 60s were sold. Besides its attractive physical appearance and good flying characteristics, it came with an unbeatable price of under $500. It was the only .60-size model sold in the USA that was available in an ARF (almost ready to fly) format. 90% of the model was built by the factory, including the installation of a Thunder Tiger 70H engine and a chrome muffler. The Raptor 60 came with a metal torque tube tail rotor drive system and a driven auto main gear system. These were features usually found on $1000 to $2000 machines.

Thunder Tiger continued their very successful Raptor series with a Raptor 50 introduced in 2005. The Raptor 50 weighs only a tad heavier than the Raptor 30, but a .50-size engine has almost double the horsepower. The Raptor 50 again pioneered and led the .50-size helicopter market worldwide.

Since the Raptor 50 was introduced, Hirobo introduced their successful Sceadu Evo 50, and a few years later Align introduced their TRex 600N. The T-Rex 600N and 700N have become very popular models because they are fresh and offer 120 degrees eCCPM control (electronic cyclic-collective pitch mixing). By 2005, Thunder Tiger started to diversify into scale helicopters. One of their main attractions at the 2005 Toy Fair was their new MD530 scale helicopter fuselage


In 2003 Hirobo of Japan introduced a very well engineered Ch-47 tandem helicopter model powered by .50 size glow engine.

The Tornado introduced in 2003 and displayed at the 2004 Fair is another exotic German design. It uses carbon material extensively, which became a
trend started 10 years ago.
designed for the Raptor 50. At only around $300, it comes painted and full of scale detail, and includes a set of scale looking landing gear. To save work, the fuselage and tail boom is one piece, there is nothing for the modeler to join or build. Thousands of their .60-.90 size MD500 Defenders have been sold world wide because the price for that painted fuselage was under $400. Now, every year, we see at least one or two new scale fuselages from Thunder Tiger.

JR led the push for eCCPM helicopters over 20 years ago, and this was their 50-size eCCPM helicopter shown at 2004 Nuremberg Fair.

2005, Alex, the inventor of the famous Picoo Z super micro helicopter demonstrating his model at the show, and he found a company that purchased his idea. In 2006 the Picoo Z wason the market.
ECCPM HEADS SPREAD
15 years ago, when JR first started making RC helicopters, JR immediately adapted the 120 degree eCCPM control system as their choice. Soon, most RC helicopter manufacturers also adapted the eCCPM control system because they are simple and elegant. In the last few years, the flagship of the JR fleet was their $3000, .90-size Super Gracy fuselaged model that won the 2005 F3C World Championships. Champion Hiroki was 16 years old when he won the F3C World Championship. Hiroki is not only good at F3C, he is also the reigning Japanese 3D Champ. A $3000 model just does not sell well in the US. Since then, JR introduced many different more affordable .50- size models. For the American market, JR started offering the .90-size JR Vibe designed by Curtis Youngblood. This proven model has gone through a few updates to make it still a viable competitor after 10 years.

This is the quintessential metal rotor head on the $3000 Hirobo Eagle helicopter used by Rudiger Feil to win the 2004 European F3C Championships.

Petr Novotny demonstrating the electric tendem CH-46 inside the MS COmposit booth in 2005.

In the last five years we saw many new flybarless helicopters and Mikado deserves the credit for leading this trend with their flybarless Logos shown in 2007.
 ENGINES EVOLVE
Webra has been making internal combustion model engines for 40 years. Over the last 10 years, I saw two very innovative engines from Webra. One was their Webra Speed 91-P5 Heli AAR. AAR stands for aluminum piston, aluminum cylinder and ringed piston. This engine is very different from other model engines. There is no removable piston sleeve. The engine crankcase is the piston sleeve. Webra engineers have came up with a coating that permits the inside surface of the silicone embedded crankcase to function like a polished aluminum sleeve. The other innovative engine was their .91-size helicopter fuel injection engine that runs on regular car gasoline. In this modeler’s opinion, Novarossi is the model engine equivalent to Ferrari in car engines. All Novarossi engines are designed and manufactured in Italy. Do you know that the founder of Novarossi is a brother of the owner of Rossi Engines? The two brothers wanted to see who could make a better engine. All Novarossi helicopter engines come with a purple heat sink and Rossis comes with a gold heat sink. These are very well made engines and their prices are no more than their Japanese counterparts. I have run Novarossi and Rossi extensively before and they are excellent.


TURBINE HELICOPTERS
German modelers are amazing tinkerers. Wolfgang Simon has spent tremendous energy to turn another one of his pet projects, a turbine powered NH-90 helicopter into a complete kit that was released by Graupner in summer 2002. This scale helicopter includes the Graupner Uni-Mechanics modified for turbine use, a NH-90 fiberglass fuselage, and a complete JetCat turbine engine and electronic engine control system. The kit includes a Y-shaped welded steel exhaust pipe. The engine exhaust comes out at the scale location located on the top of the helicopter. The whole package is approximately US $6,000 and was thoroughly
tested and proven so that the modeler does not have to spend valuable time tweaking and tinkering.


The $3000 Caliber 90 from Kyosho was the crème de la crème of F3C competition helicopters from 1998 to now.
Wolfgang said turbines are not as difficult to operate as most people imagine. For example, a standard glow plug can be used to ignite the engine, but the trick is to pull the platinum coil out slightly. The microprocessor engine control unit automatically controls the engine starting sequence and governs the engine during flight. Most earlier home built RC turbine helicopters did not have a true transmission. Most home built turbine helis use the engine exhaust to drive a turbine, that turbine is then geared down to drive the main rotor; the drawback is low work efficiency. The Graupner NH-90/JetCat system has a true mechanical transmission. The turbine engine compressor/turbine shaft drives a gear reduction system. The output of the gear reduction system is connected to a centrifugal clutch about the size of a regular 60-size helicopter clutch. Then the clutch bell turns the helicopter main gear.
 ELECTRICS
During the last two decades, I noticed the endurance of electric helicopters has also improved by about 10% each year. In 1977, my first electric RC helicopter, an Ishimasa EH-1 powered by two Mabuchi 550 tin can motors and eight 1200mAh NiCd cells could only hover for 1 minute, and now most electric models can hover for 10 to 20 minutes when using LiPo cells. Although in the US and in Japan we still see glow powered RC helicopters dominating the flying field, in Europe, electric helicopter developments have now exceeded glow engine development. Big and small companies in Europe are all concentrating on designing new electric helicopters.


In the last five years at the Nuremberg Toy Fair, there was a noticeable change, more new electric helicopters were introduced than engine powered models. Many of the new models were mini sized electric helicopters. Mini helicopters are inexpensive to produce or copy, so the barrier to entry into the micro market is very low. Medium and large electric helicopters are more challenging to design, and the match between kit, motor and speed controller is critical. Medium to large electric helicopters cannot achieve their full performance potential if the motor or battery choice is not optimized. There are many larger, higher-performance, higher-priced electric helicopters, like the Joker, Hanseleit NT, T-Rex 600, and Mikado Logo.


Ralf Buxnolwitz, the owner of Mikado enjoys designing and flying electric helicopters so much he wants to offer a new Logo helicopter design every year. Mikado Company of Berlin, Germany introduced the Logo 20 in 1999, Logo 16 in 2000, Logo 10 in 2001, the Bionics Logo 24 in 2002, Logo 14 in 2003 and then these were followed by the Logo 14 3D, Logo 600, Logo 500, Logo 400 and flybarless Logo! Modern electric helicopters like the Logo combined with powerful brushless motors and high energy density LiPo batteries have permitted modern electric helicopters to have fantastic flight performances that match nitro fuel engine powered RC helicopters.


Owing to space limitations, we will close here, but in the future we will discuss many of these wonderful new models, and more, in some detail.