Toy Airplanes
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A radio-controlled (model) aircraft (often called RC aircraft or RC plane) is a small flying machine that is controlled remotely by an operator on the ground using a hand-held radio transmitter. The transmitter communicates with a receiver within the craft that sends signals to servomechanisms (servos) which move the control surfaces based on the position of joysticks on the transmitter. The control surfaces, in turn, affect the orientation of the plane.
Flying RC aircraft as a hobby has been growing worldwide with the advent of more efficient motors (both electric and miniature internal combustion or jet engines), lighter and more powerful batteries and less expensive radio systems. A wide variety of models and styles is available.
Scientific, government and military organizations are also utilizing RC aircraft for experiments, gathering weather readings, aerodynamic modeling and testing, and even using them as drones or spy planes.
The earliest examples of electronically guided model aircraft were hydrogen-filled model airships of the late 19th century. They were flown as a music hall act around theater auditoriums using a basic form of spark-emitted radio signal.[2] In the 1920s, the Royal Aircraft Establishment of Britain built and tested the pilotless Larynx, a monoplane with a 100-mile (160 km) range. It was not until the 1930s that the British came up with the Queen Bee, a gunnery target version of the de Havilland Tiger Moth, and similar target aircraft. Radio control systems for model aircraft were developed in the late 1940s and early 1950s by English enthusiasts such as Howard Boys, who patented his 'Galloping Ghost' system of proportional control and became a regular contributor to Aeromodeller on the topic.[3]
In the United States, two pioneers in the field of controlling model planes by radio were Ross Hull and Clinton DeSoto, officers of the American Radio Relay League. During 1937, these two men successfully built and flew several large R/C gliders in the first public demonstration of controlled flights, in the course of which their sailplanes made more than 100 flights. A scheduled R/C event at the 1937 National Aeromodeling Championships attracted six entrants: Patrick Sweeney, Walter Good, Elmer Wasman, Chester Lanzo, Leo Weiss and B. Shiffman, Lanzo winning with the lightest (6 pounds) and simplest model plane, although his flight was rather erratic and lasted only several minutes. Sweeney and Wasman both had extremely short (5-second) flights when their aircraft took off, climbed steeply, stalled and crashed. Sweeney, however, had the distinction of being the first person to attempt a R/C flight in a national contest. The other three entrants were not even able to take off, although Good, with his twin brother William, persisted with developing R/C systems, culminating in first placings in the 1940 US Nationals and again after the end of World War II, in 1947. Their historic R/C model airplane, which they named the “Guff,” was presented to the National Air and Space Museum in Washington, D.C., in May, 1960, where it can be seen today.[4]
Types[edit source | editbeta]
There are many types of radio-controlled aircraft. For beginning hobbyists, there are park flyers and trainers. For more advanced pilots there are glow plug engine, electric powered and sailplane aircraft. For expert flyers, jets, pylon racers, helicopters, autogyros, 3D aircraft, and other high-end competition aircraft provide adequate challenge. Some models are made to look and operate like a bird instead. Replicating historic and little known types and makes of full-size aircraft as "flying scale" models, which are also possible with control line and free flight types of model aircraft, actually reach their maximum realism and behavior when built for radio control flying.
Radio control scale aircraft modeling[edit source | editbeta]
This Kyosho "Phantom 70" biplane is a semi-scale replica of a class winner and record holder from the 2007 Reno Air Races. In this example, the fuselage with its complex curves as well as the engine cowl, wheel pants and wing struts are rendered in fiberglass. The wings and horizontal stabilizer are traditional balsa/plywood construction
Perhaps the most realistic form of aeromodeling, in its main purpose to replicate full-scale aircraft designs from aviation history, for testing of future aviation designs, or even to realize never-built "proposed" aircraft, is that of radio control scale aeromodeling, as the most practical way to re-create "vintage" full-scale aircraft designs for flight once more, from long ago. RC Scale model aircraft can be of any type of steerable airship lighter-than-air (LTA) aviation craft, or more normally, of the heavier-than-air fixed wing glider/sailplane, fixed-wing single or multi-engine aircraft, or rotary-wing aircraft such as autogyros or helicopters.
Full-scale aircraft designs from every era of aviation, from the "Pioneer Era" and World War I's start, through to the 21st century, have been modeled as radio control scale model aircraft. Builders of RC Scale aircraft can enjoy the challenge of creating a controllable, miniature aircraft that merely "looks" like the full scale original in the air with no "fine details", such as a detailed cockpit, or seriously replicate many operable features of a selected full scale aircraft design, even down to having operable cable-connected flight control surfaces, illuminated navigation lighting on the aircraft's exterior, realistically retracting landing gear, etc. if the full-sized aircraft possessed such features as part of its design.
Various scale sizes of RC scale aircraft have been built in the decades since modern digital-proportional, miniaturized RC gear came on the market in the 1960s, and everything from indoor-flyable electric powered RC Scale models, to "giant scale" RC Scale models, in scale size ranges that usually run from 20% to 25%, and upwards to 30 to 50% size of some smaller full scale aircraft designs, that can replicate some of the actual flight characteristics of the full scale aircraft they are based on, have been enjoyed, and continue to be built and flown, in sanctioned competition and for personal pleasure, as part of the RC scale aeromodeling hobby.
Sailplanes and gliders[edit source | editbeta]
F3A Pattern Ship - ZNline Alliance by CPLR
Shinden by Bryan Hebert
Main article: radio-controlled glider
Gliders are planes that do not typically have any type of propulsion. Unpowered glider flight must be sustained through exploitation of the natural lift produced from thermals or wind hitting a slope. Dynamic soaring is another popular way of providing energy to gliders that is becoming more and more common. However, even conventional slope soaring gliders are capable of achieving speeds comparable with similar sized powered craft. Gliders are typically partial to slow flying and have high aspect ratio, as well as very low wing loading (weight to wing area ratio). 3-channel gliders which use only rudder control for steering and dihedral or polyhedral wing shape to automatically counteract rolling are popular as training craft, due to their ability to fly very slowly and high tolerance to error.
Powered gliders have recently seen an increase in popularity. By combining the efficient wing size and wide speed envelope of a glider airframe with an electric motor, it is possible to achieve long flight times and high carrying capacity, as well as glide in any suitable location regardless of thermals or lift. A common method of maximising flight duration is to quickly fly a powered glider upwards to a chosen altitude and descending in an unpowered glide. Folding propellers which reduce drag (as well as the risk of breaking the propellor) are standard. Powered gliders built with stability in mind and capable of aerobatics, high speed flight and sustained vertical flight are classified as 'Hot-liners'. 'Warm-liners' are powered craft with similar abilities but less extreme thrust capability. Many powered beginner craft are based upon or considered borderline gliders.
To avoid ambiguity, unpowered gliders are typically referred to as 'slope soarers' or 'thermal soarers' respectively.
Jets[edit source | editbeta]
Jets tend to be very expensive and commonly use a micro turbine or ducted fan to power them. Most airframes are constructed from fiber glass and carbon fiber. For electric powered flight which are usually powered by electric ducted fans, may be made of styrofoam. Inside the aircraft, wooden spars reinforce the body to make a rigid airframe . They also have kevlar fuel tanks for the Jet A fuel that they run on. Most micro turbines start with propane, burn for a few seconds before introducing the jet fuel by solenoid. These aircraft can often reach speeds in excess of 320 km/h (200 mph). They require incredibly quick reflexes and very expensive equipment, so are usually reserved for the expert.
In the U.S.A the FAA heavily regulates flying of such aircraft to only approved AMA Academy of Model Aeronautics sites, in where certified turbine pilots may fly. Also, the AMA requires model aviation enthusiasts who wish to operate miniature gas turbine powered RC model aircraft, to be certified in the operation of the type of gas turbine engine, and all aspects of safety in operating such a turbine-powered model aircraft, that they need to know in flying their model.[1]. Some military bases allow such high tech aircraft to fly within limited airspace such as Kaneohe Marine base in Hawaii, and Whidbey Island NAS in Washington State.
An average turbine aircraft will cost between $150–$10,000 with more than $20,000 all-up becoming more common. Many manufactures sell airframes such as Yellow Aircraft and Skymaster. Turbines are produced from The Netherlands (AMT)to Mexico (Artes Jets). The average microturbine will cost between $2500 and $5000 depending on engine output. Smaller turbines put out about 12 lbf (53 N) of thrust, while larger microturbines can put out as much as 45 lbf (200 N) of thrust. Radio control jets require an on board FADEC (Full Authority Digital Engine Control) controller, this controls the turbine, just like a larger turbine. RC Jets also require electrical power. Most have a lithium polymer (LiPo) battery pack at 8-12 volts that control the FADEC. There is also a LiPo for the onboard servos that control ailerons, elevator, rudder, flaps and landing gear.
Of much less complexity are the types of RC jet aircraft that actually use an electric motor-driven ducted fan instead to power the aircraft. So called "EDF" models can be of much smaller size, and only need the same electronic speed contoller and rechargeable battery technology as propeller-driven RC electric powered aircraft use.
Pylon racers[edit source | editbeta]
Racers are small propeller-driven aircraft that race around a 2, 3, or 4 pylon track. They tend to be hard to see and can often go over 240 km/h (150 mph), though some people do pylon races with much slower aircraft. Although several different types of aircraft are raced across the world, those flown primarily in the US are; Q500 (424 or ARPRA, and 428), and Q40. 424 is designed as a starting point into the world of pylon racing. Inexpensive (under $200 for the airframe) kits with wing areas of 3,200 square centimetres (500 sq in) are flown with .40 size engines that can be purchased for less than $100. The goal is for the planes to be not only inexpensive, but closely matched in performance. This places the emphasis on good piloting. APRA is a version of 424 with specific rules designed for consistency. 428 aircraft are similar to 424 in appearance. The difference is in engine performance and construction. The planes are primarily made of fiberglass with composites used at high load points. Wings are often hollow to save weight. (All aircraft must meet a minimum weight. A lighter wing moves more of the weight closer to the center of gravity. This requires less control deflection and its resulting drag to change the planes attitude.) They also use .40 cu in size engines but unlike 424 they are much more expensive. They have been designed to put out the maximum amount of power at a specific RPM using a specific fuel. Nelson manufactures the most predominantly used engine. Speeds are very fast in this class with planes capable of reaching 290 km/h (180 mph). Q40 is the highpoint of pylon racing, as their aircraft resemble full-size race planes. They are not limited to the simple shapes that Q500 planes are, which have much cleaner aerodynamics and less wing area. They use the same basic Nelson engine used in 428, but the engine is tuned to turn a much smaller prop at a much higher rpm. The planes accelerate much more slowly than 428, but their clean airframes allow them to reach higher speeds, and maintain them around the turns. These planes can fly in excess of 320 km/h (200 mph) on the course. Because of their limited wing area however, Q40 planes must fly a larger arc around the pylons to conserve energy. Although faster, they ultimately fly a larger course. Ironically the best times for a 10 lap 3 pylon Q40 race are very close to the same in 428.
Helicopters[edit source | editbeta]
Main article: radio-controlled helicopter
Radio-controlled helicopters, although often grouped with RC aircraft, are in a class of their own because of the vast differences in construction, aerodynamics and flight training. Hobbyists will often venture from planes, to jets and to helicopters as they enjoy the challenges, excitement and satisfaction of flying. Some radio-controlled helicopters have photo or video cameras installed and are used for aerial imaging or surveillance. Newer "3d" radio control helicopters can fly inverted with the advent of advanced swash heads, and servo linkage that enables the pilot to immediately reverse the pitch of the blades, creating a reverse in thrust.
Flying bird models, or ornithopters[edit source | editbeta]
Some RC models take their inspiration from nature. These may be gliders made to look like a real bird, but more often they actually fly by flapping wings. Spectators are often surprised to see that such a model can really fly. These factors as well as the added building challenge add to the enjoyment of flying bird models, though some ARF (almost-ready-to-fly) models are available. Flapping-wing models are also known as ornithopters, the technical name for an aircraft whose driving airfoils oscillate instead of rotate.
Toy-class RC[edit source | editbeta]
Since about 2004, new, more sophisticated toy RC airplanes, helicopters, and ornithopters have been appearing on toy store shelves. This new category of toy RC distinguishes itself by:
Proportional (vs. "on-off") throttle control which is critical for preventing the excitation of phugoid oscillation ("porpoising") whenever a throttle change is made. It also allows for manageable and steady altitude control and reduction of altitude loss in turns.
LiPo batteries for light weight and long flight time.
EPP (Expanded Polypropylene) foam construction making them virtually indestructible in normal use.
Low flying speed and typically rear-mounted propeller(s) make them harmless when crashing into people and property.
Stable spiral mode resulting in simple turning control where "rudder" input results in a steady bank angle rather than a steady roll rate.
As of 2013, the toy class RC airplane typically has no elevator control. This is to manage costs, but it also allows for simplicity of control by unsophisticated users of all ages. The downside of lack of elevator control is a tendency for the airplane to phugoid. To damp the phugoid oscillation naturally, the planes are designed with high drag which reduces flight performance and flying time. The lack of elevator control also prevents the ability to "pull back" during turns to prevent altitude loss and speed increase.
Costs range from 20 to 40 USD. Crashes are common and inconsequential. Throttle control and turning reversal (when flying toward the pilot) rapidly become second-nature, giving a significant advantage when learning to fly a more costly hobby class RC aircraft.
3D flight[edit source | editbeta]
Model of an mx2, a 3D aerobatic aircraft with a wingspan of 121 cm.
3D flight is a type of flying in which model aircraft have a thrust-to-weight ratio of more than 1:1 (typically 1.5:1 or more), large control surfaces with extreme throws, low weight compared to other models of same size and relatively low wing loadings.
These elements allow for spectacular aerobatics such as hovering, 'harriers', torque rolling, blenders, rolling circles, and more; maneuvers that are performed below the stall speed of the model. The type of flying could be referred to as 'on the prop' as opposed to 'on the wing', which would describe more conventional flight patterns that make more use of the lifting surfaces of the plane.
3D has created a huge market for electric indoor 'profile' types similar to the Ikarus 'Shockflyers' designed to be able to fly inside a gym or outside in little wind. These generally make use of small brushless motors (often outrunners, but also geared inrunners) and lithium polymer batteries. There are also many larger 3D designs designed for two and four stroke glow engines, two stroke gas engines and large electric power systems. The most common and which most pilots describe as the best size of a 3D plane is a 40%/150cc class.
Toy Airplanes
Toy Airplanes
Toy Airplanes
Toy Airplanes
Toy Airplanes
Toy Airplanes
Toy Airplanes
Toy Airplanes
Toy Airplanes
Toy Airplanes
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