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A radio control yer (holding a transmitter) guides his aircraft
A radio control yer (holding a transmitter) guides his aircraft in for a landingin for a landing
A
A radio-controlledradio-controlledaircraftaircraft (often called RC aircraft or (often called RC aircraft or RC plane) is aRC plane) is a model aircraftmodel aircraft that is controlled that is controlled remotely
remotely, typically with , typically with a hand-helda hand-held transmittertransmitterand aand a receierreceier within the craft! "he receier controls within the craft! "he receier controls the corresponding
the corresponding serosserosthat moe thethat moe the control surfacescontrol surfaces #ased on the position of #ased on the position of $oysticks $oystickson theon the transmitter
transmitter, which in turn a%ect the , which in turn a%ect the orientation of the plane!orientation of the plane!
Flying RC aircraft as a
Flying RC aircraft as a ho##yho##yhas #een growing worldwide with the adent of more e&cient motorshas #een growing worldwide with the adent of more e&cient motors (#oth
(#oth electricelectric and miniature and miniature internal com#ustioninternal com#ustion or or $et engines $et engines), lighter and more), lighter and more powerful
powerful #atteries#atteries and less e'pensie radio systems! A wide ariety of models and and less e'pensie radio systems! A wide ariety of models and styles is aaila#le!styles is aaila#le!
cientic, goernment and military organi*ations are also utili*ing RC aircraft for e'periments, cientic, goernment and military organi*ations are also utili*ing RC aircraft for e'periments, gathering weather readings,
gathering weather readings, aerodynamicaerodynamicmodeling and testing, and een using them asmodeling and testing, and een using them as dronesdronesor spyor spy planes!
planes! "ypes "ypes
"here are many types
"here are many types of radio-controlled aircraft! For #eginning ho##yists, there areof radio-controlled aircraft! For #eginning ho##yists, there are parkpark yers
yersandandtrainerstrainers! For more adanced pilots there are! For more adanced pilots there are glow plugglow plug engine, electric powered engine, electric powered and
and sailplanesailplaneaircraft! For e'pert yers, $ets, pylon aircraft! For e'pert yers, $ets, pylon racers,racers, helicoptershelicopters,, autogyrosautogyros, + aircraft, and, + aircraft, and other high end competition aircraft proide adeuate challenge! ome models are made to look and other high end competition aircraft proide adeuate challenge! ome models are made to look and operate like a #ird instead! Replicating historic and little known types and makes of full-si*e aircraft as operate like a #ird instead! Replicating historic and little known types and makes of full-si*e aircraft as .ying scale. models, which are also possi#le with
.ying scale. models, which are also possi#le with control linecontrol lineandand free ightfree ight types of model aircraft, types of model aircraft, actually reach their ma'imum realism and #ehaior when #uilt for
actually reach their ma'imum realism and #ehaior when #uilt for radio control ying!radio control ying! //editedit0Radio control scale aircraft 0Radio control scale aircraft modelingmodeling
"his
"his 1yosho1yosho .2hantom 34. #iplane is a semi-scale replica of .2hantom 34. #iplane is a semi-scale replica of a class winner and record holder from thea class winner and record holder from the 5443
wheel pants and wing struts are rendered in
wheel pants and wing struts are rendered in #erglass! "he wings and hori*ontal sta#ili*er are#erglass! "he wings and hori*ontal sta#ili*er are traditional #alsa7plywood construction
traditional #alsa7plywood construction
2erhaps the most realistic form of aeromodeling, in its main purpose to
2erhaps the most realistic form of aeromodeling, in its main purpose to replicate full-scale aircraftreplicate full-scale aircraft designs from aiation history, for testing of future aiation designs, or een to reali*e neer-#uilt designs from aiation history, for testing of future aiation designs, or een to reali*e neer-#uilt .proposed. aircraft, is that of radio control scale aeromodeling! RC cale model aircraft can #e of any .proposed. aircraft, is that of radio control scale aeromodeling! RC cale model aircraft can #e of any type of steera#le
type of steera#le airshipairshiplighter-than-air (8lighter-than-air (8"A) aiation craft, or "A) aiation craft, or more normally, of the heaier-than-airmore normally, of the heaier-than-air 'ed wing glider7sailplane, 'ed-wing single or multi-engine aircraft, or rotary-wing aircraft such as 'ed wing glider7sailplane, 'ed-wing single or multi-engine aircraft, or rotary-wing aircraft such as autogyros or helicopters!
autogyros or helicopters!
Full-scale aircraft designs from eery era of aiation, from the .2ioneer 9ra. up to
Full-scale aircraft designs from eery era of aiation, from the .2ioneer 9ra. up toWorld War 6World War 6::s start,s start, through to the modern day in the 5;st century, hae #een modeled as radio control scale model through to the modern day in the 5;st century, hae #een modeled as radio control scale model aircraft! <uilders of RC cale aircraft can en$oy the
aircraft! <uilders of RC cale aircraft can en$oy the challenge of creating a controlla#le, miniaturechallenge of creating a controlla#le, miniature aircraft that merely .looks. like the full scale original
aircraft that merely .looks. like the full scale original in the air with no in the air with no .ne details., such as a.ne details., such as a detailed cockpit, or go into seriously replicating many opera#le features of a selected full s detailed cockpit, or go into seriously replicating many opera#le features of a selected full s calecale aircraft design, een down to
aircraft design, een down to haing opera#le ca#le-connected ight control surfaces, illuminatedhaing opera#le ca#le-connected ight control surfaces, illuminated naigation lighting on the
naigation lighting on the aircraft:s e'terioraircraft:s e'terior, realistically retracting , realistically retracting landing gearlanding gear, etc! if , etc! if the full-si*edthe full-si*ed aircraft possessed such features as part of its
aircraft possessed such features as part of its design!design!
=arious scale si*es of RC scale aircraft hae #een #uilt in
=arious scale si*es of RC scale aircraft hae #een #uilt in the decades since modern digital-the decades since modern
digital-proportional, miniaturi*ed RC gear came on the market in the ;>?4s, and eerything from proportional, miniaturi*ed RC gear came on the market in the ;>?4s, and eerything from indoor-ya#le electric powered RC cale models, to enormous .giant scale. RC cale models, in scale si*e ya#le electric powered RC cale models, to enormous .giant scale. RC cale models, in scale si*e ranges that usually run from 54@ to 5@,
ranges that usually run from 54@ to 5@, and upwards to +4 to 4@ si*e of some smaller full and upwards to +4 to 4@ si*e of some smaller full scalescale aircraft designs, that can ama*ingly replicate some of the actual ight
aircraft designs, that can ama*ingly replicate some of the actual ight characteristics of the full scalecharacteristics of the full scale aircraft they are #ased on, hae #een en$oyed, and continue to #e
aircraft they are #ased on, hae #een en$oyed, and continue to #e #uilt and own, in sanctioned#uilt and own, in sanctioned competition and for personal pleasure, as
competition and for personal pleasure, as part of the part of the RC scale aeromodeling ho##yRC scale aeromodeling ho##y!! //editedit0ailplanes and gliders0ailplanes and gliders
F+A 2attern hip - Bline Alliance #y C28R F+A 2attern hip - Bline Alliance #y C28R
hinden #y <ryan De#ert
Main article: radio-controlled glider
Eliders are planes that do not typically hae any type of propulsion, as a general rule! <ecause most gliders are unpowered, ight must #e sustained through e'ploitation of the natural lift produced from thermals or wind hitting a slope! ynamic soaring is another popular way of proiding energy to gliders that is #ecoming more and more common!
/edit0ets
ets tend to #e ery e'pensie and commonly use a micro tur#ine or ducted fan to power them! Gost airframes are constructed from #er glass and car#on #er! 6nside the aircraft, wooden spars
reinforce the #ody to make a rigid airframe ! "hey also hae kelar fuel tanks for the et A fuel that they run on! Gost micro tur#ines start with propane, #urn for a few seconds #efore introducing the $et fuel #y solenoid! "hese aircraft can often reach speeds in e'cess of +54 km7h (544 mph)! "hey reuire incredi#ly uick ree'es and ery e'pensie euipment, so are usually resered for the e'pert! "he FAA heaily regulates ying of such aircraft to only approed AGA (Academy of Godel Aeronautics) sites, in where certied tur#ine pilots may y! Also, the AGA reuires model aiation enthusiasts who wish to operate miniature gas tur#ine powered RC model aircraft, to #e certied in the operation of the type of gas tur#ine engine, and all aspects of safety in operating such a tur#ine-powered model aircraft, that they need to know in ying their model!/;0! ome military #ases allow such high tech aircraft to y within limited airspace such as 1aneohe Garine #ase in Dawaii, and Whid#ey 6sland A in Washington tate! An aerage tur#ine aircraft will cost #etween H;4IH;4,444 with more than H54,444 all-up #ecoming more common! Gany manufactures sell airframes such as Jellow Aircraft and kymaster! "ur#ines are produced from "he etherlands (AG")to Ge'ico (Artes ets)! "he aerage microtur#ine will cost #etween H544 and H444 depending on engine output! maller tur#ines put out a#out ;5 l#f (+ ) of thrust, while larger microtur#ines can put out as much as K l#f (544 ) of thrust! Radio control $ets reuire an on #oard FA9C (Full Authority igital 9ngine Control) controller, this controls the tur#ine, $ust like a larger tur#ine! RC ets also reuire electrical power! Gost hae a
862L (8ithium 2olymer pack) at M-;5 olts that control the FA9C! "here is also a 862L for the on#oard seros that control ailerons, eleator, rudder, aps and landing gear!
/edit02ylon racers
Racers are small propeller aircraft that race around a 5 , +, or K pylon track! "hey tend to #e hard to see and can often go oer 5K4 km7h (;4 mph), though some people do pylon races with much slower aircraft! Although seeral di%erent types of aircraft are raced across the world, those own primarily in the N areO P44 (K5K or AR2RA, and K5M), and PK4! K5K is designed as a starting point into the world of pylon racing! 6ne'pensie (under H544 for the airframe) kits with wing areas of +,544 suare centimetres (44 s in) are own with !K4 si*e engines that can #e purchased for less than H;44! "he goal is for the planes to #e not only ine'pensie, #ut closely matched in performance! "his places the emphasis on good piloting! A2RA is a ersion of K5K with specic rules designed for consistency! K5M aircraft are similar to K5K in appearance! "he di%erence is in engine performance and construction! "he planes are primarily made of #erglass with composites used at high load points! Wings are often hollow to sae weight! (All aircraft must meet a minimum weight! A lighter wing moes more of the weight closer to the center of graity! "his reuires less control deection and its resulting drag to change the planes attitude!) "hey also use !K4 si*e engines #ut unlike K5K they are much more
e'pensie! "hey hae #een designed to put out the ma'imum amount of power at a specic R2G using a specic fuel! elson manufactures the most predominantly used engine! peeds are ery fast in this class with planes capa#le of reaching 5>4 km7h (;M4 mph)! PK4 is the highpoint of pylon racing, as their aircraft resem#le full si*e race planes! "hey are not limited to the simple shapes that P44 planes are, which hae much cleaner aerodynamics and less wing area! "hey us e the same #asic elson engine used in K5M, #ut the engine is tuned to turn a much smaller prop at a much higher rpm! "he planes accelerate much more slowly than K5M, #ut their clean airframes allow them to reach higher speeds, and maintain them around the turns! "hese planes can y in e'cess of +54 km7h (544 mph) on the course! <ecause of their limited wing area howeer, PK4 planes must y a larger arc around the pylons to consere energy! Although faster, they ultimately y a larger course! 6ronically the #est times for a ;4 lap + pylon PK4 race are ery close to the same in K5M!
/edit0Delicopters
Main article: radio-controlled helicopter
Radio-controlled helicopters, although often grouped with RC aircraft, are in a c lass of their own #ecause of the ast di%erences in construction, aerodynamics and ight training! Do##yists will often enture from planes, to $ets and to helicopters as they en$oy the challenges, e'citement and
satisfaction of ying! ome radio-controlled helicopters hae photo or ideo cameras installed and are used for aerial imaging or sureillance! ewer .+d. radio control helicopters can y inerted with the
adent of adanced swash heads, and sero linkage that ena#les the pilot to immediately reerse the pitch of the #lades, creating a reerse in thrust!
/edit0Flying #ird models, or ornithopters
ome RC models take their inspiration from nature! "hese may #e gliders made to look like a real #ird, #ut more often they actually y #y apping wings! pectators are often surprised to see that such a model can really y! "hese factors as well as the added #uilding challenge add to the en$oyment of ying #ird models, though some ARF ( almost-ready-to-y) models are aaila#le! Flapping-wing models are also known as ornithopters, the technical name for an aircraft whose driing airfoils oscillate instead of rotate!
/edit0"oy-class RC
ince a#out 544K, new, more sophisticated toy RC airplanes, helicopters, and ornithopters hae #een appearing on toy store sheles! "his new category of toy RC distinguishes itself #yQ
2roportional (s! .on-o%.) throttle control which is critical for preenting the e'citation of phugoid oscillation (.porpoising.) wheneer a throttle change is made! 6t also al lows for managea#le and steady altitude control and reduction of altitude loss in tu rns!
8ithium polymer #atteries for light weight and long ight ti me!
922 (9'panded 2olypropylene) foam construction making them .indestructi#le. in normal crash-prone use!
8ow ying speed and typically rear-mounted propeller(s) make them harmless when crashing into people and property!
ta#le spiral mode resulting in simple turning control where .rudder. input results in a steady #ank angle rather than a steady roll rate!
As of 544>, the toy class RC airplane typically has no eleator control! "his is to manage costs, #ut it also allows for simplicity of control #y unsophisticated users of all ages! "he down side of lack of eleator control is a tendency for the airplane to phugoid! "o damp the phugoid oscillation naturally, the planes are designed with high drag which reduces ight performance and ying time! "he lack of eleator control also preents the a#ility to .pull #ack. during turns to preent altitude loss and speed increase!
Costs range from 54 to K4 N! Crashes are common and inconseuential! "hrottle control and turning reersal (when ying toward the pilot) rapidly #ecome second-nature, giing a signicant adantage when learning to y a more costly ho##y class RC aircraft!
/edit0+ ight
+ ight is a type of ying in which model aircraft hae a thrust-to-weight ratio of more than ;Q; (typically ;!Q; or more), large control surfaceswith e'treme throws, low weight compared to other models of same si*e and relatiely low wing loadings!
"hese elements allow for spectacular aero#atics such as hoering, :harriers:, torue rolling, #lenders, rolling circles, and more, maneuers that are performed #elow the stall speed of the model! "he type of ying could #e referred to as :on the prop: as opposed to :on the wing:, which would descri#e more conentional ight patterns that make more use of the lifting surfaces of the plane!
+ has created a huge market for electric indoor :prole: types s imilar to the 6karus :hockyers: designed to #e a#le to y inside a gym or outside in little wind! "hese generally make use of
small #rushless motors (often outrunners, #ut also geared inrunners) and lithium polymer #atteries! "here are also many larger + designs designed for two and four stroke glow engines, two stroke gas engines and large electric power systems! "he most common and which most pilots descri#e as the #est si*e of a + plane is a K4@7;4cc class!
/edit0"ypes of kits and construction
"here are arious ways to construct and assem#le an RC aeroplane! =arious kits are aaila#le, reuiring di%erent amounts of assem#ly, di%erent costs and arying leels of skill and e'perience!
ome kits can #e mostly foam or plastic, or may #e all #alsa wood! Construction consists of
using formers and longerons for the fuselage, and spars and ri#s for the wings and tail s urfaces! Gore ro#ust designs often use solid sheets of wood to form these structures instead, or might employ a composite wing consisting of an e'panded polystyrene core coered in a protectie eneer of wood, often o#echi! uch designs tend to #e heaier than an euialent si*ed model #uilt using the
traditional method, and would #e much more likely to #e found in a power model than a glider! "he lightest models are suita#le for indoor ight, in a windless enironment! ome of these are made #y #ringing frames of #alsa wood and car#on #er up through water to pick up thin plastic lms, similar to rain#ow colored oil lms! "he adent of . foamies,. or craft in$ection-molded from lightweight foam and sometimes reinforced with car#on #er, hae made indoor ight more readily accessi#le to
ho##yists! .Crash proof. 922 (9'panded 2olypropylene) foam planes are actually een #enda#le and usually sustain ery little or no damage in the eent of an accident, een after a nose die! ome companies hae deeloped similar material with di%erent names, such as AeroCell or 9lapor!
"he late ;>M4s saw a range of models from the Nnited tates company N AirCore cleerly using twinwall polypropylene material! "his dou#le skinned :Corre': or :Coroplast: was commonly used in adertising and industry, #eing readily aaila#le in at sheet form, easily printed and die cut! Godels were pre-decorated and aaila#le in AR"F form reuiring relatiely straightforward, interlocking assem#ly secured with contact adhesie! "he material thickness (usually +?mm) and corresponding density meant that models were uite weighty (upwards of l#or 5 kg) and conseuently had a#oe aerage ying speeds! "he range were powered using a cleer (interchangea#le) cartridge motor mount designed for the #etter, more powerful 4!K4 cu in (?!? cmS) glow engines! Aircore faded from the scene around the Gillennium!
Coincidently this is when the material was used e'perimentally #y Gugi-the small tough delta glider was inented! "his rapidly deeloped into a high performance design-the Gugi 9o! 2opular worldwide as the plans were immediately launched freely on the 6nternet! Any grade or thickness of the material can #e used #y appropriate scaling! Doweer the optimum material is twinwalled polypropylene sheet in 5mm thickness and at +4gsm (density)
Amateur ho##yists hae more recently deeloped a range of new model designs utili*ing
the corrugated plastic or .Coroplast. material! "hese models are collectiely called .2As. which stands for imple 2lastic Airplane esign! Fans of the 2A concept tout increased dura#ility, ease of #uilding, and lower priced materials as opposed to #alsa models, sometimes (though not always) at the e'pense of greater weight and crude appearance!
Flying models hae to #e designed according to the same principles as full-si*ed aircraft, and therefore their construction can #e ery di%erent from most static models! RC planes often #orrow construction techniues from intage full-si*ed aircraft (although they rarely use metal s tructures)! /edit0Ready to y
2arkBone 2-; Gustang
Ready to y (or R"F) planes come as pre-assem#led kits that usually only reuire wing attachment or other #asic assem#ly! "ypically, eerything that is needed is already in the kit! R"F planes can #e up in the air in $ust a few minutes and hae all #ut eliminated assem#ly time (at the e'pense of the model:s conguration options!) Among traditional ho##yist #uilders, R"F models are a point of controersy, as many consider model assem#ly, fa#rication and een design as integral to the ho##y!
/edit0Almost ready to y
Main article: Almost Ready to Fly
"his Ereat 2lanes upermarine pitre 8F Gk T66 wears the markings of the 555 uadron and is an e'ample of an almost ready to y model
Almost ready to y (or ARF or AR"F) kits are similar to R"F kitsO howeer usually reuire more assem#ly and sometimes #asic construction! "he aerage ARF aircraft can #e #uilt with less than K hours of la#or, ersus 54I4U hours (depending on detail and desired results) for a traditional kit aircraft! "he fuselage and appendages are normally already constructed! "he kit will usually reuire separate purchase and installation of seros, choice of motor (gas, glow fuel, or electric), s peed controller (electric) and occasionally control rods! "his is an adantage oer R"F kits, as most model aircraft enthusiasts already own their euipment of choice, and only desire an airframe!
/edit0<alsa kit
<alsa kits come in many si*es and skill leels! "he #alsa wood may either #e cut with a die-cut orlaser! 8aser cut kits hae a much more precise construction and much tighter tolerances, #ut tend to cost more than die-cut kits!
"he kit usually contains most of the raw material needed for an unassem#led plane, a set of (sometimes ela#orate) assem#ly instructions, and a few spare parts to allow for #uilder error! Assem#ling a model from plans or a kit can #e ery la#or-intensie! 6n order to complete the
construction of a model, the #uilder typically spends many hours assem#ling the frame, coering it, and polishing7rening the control surfaces for correct alignment! "he kit does not include necessary
tools, and these hae to #e purchased separately! A single oerlooked error during assem#ly could compromise the model:s airworthiness, leading to a crash that destroys the model!
maller #alsa kits will often come complete with the necessary parts for the primary purpose of non-ying modeling or ru##er #and ight! "hese kits will usually also come with conersion instructions to y as glow (gas powered) or electric and can #e own free-ight or radio-controlled! Conerting a kit reuires additional and su#stitution parts to get it to y properly such as the addition of seros, hinges, speed controls, control rods and #etter landing gear mechanisms and wheels!
Gany kits will come with a tissue paper coering that then gets coered with multiple layers of plane dope which coats and strengthens the fuselage and wings in a plastic-like coering! 6t has #ecome more common to coer planes with heat-shrinking plastic lms #acked with heat-sensitie adhesie! "hese lms are generally known as :iron-on coering: since a hand-held iron allows the lm to #e attached to the frameO a higher temperature then causes the lm to tighten! "his plastic coering is more dura#le and makes for a uick repair! Lther arieties of heat shrinka#le coerings are also
aaila#le, that hae #rous reinforcements within the plastic lm, or are actual woen heat shrinka#le fa#rics!
6t is common to leae landing gear o% smaller planes (roughly +?. or smaller) in order to sae on weight, drag and construction costs! "he planes can then #e launched #y hand-launching, as with smaller free-ight models, and can then land in soft grass!
/edit0From plans or scratch
2lanes can #e #uilt from pu#lished plans, often supplied as full si*ed drawings with included
instructions! 2arts normally need to #e cut out from sheet wood using supplied templates! Lnce all of the parts hae #een made, the pro$ect #uilds up $ust like another kit! A model plane #uilt from scratch ends up with more alue #ecause you created the pro$ect from the plans! "here is more choice of plans and materials than with kits, and the latest and more speciali*ed designs are usually not aaila#le in kit form! "he plans can #e scaled to any desired si*e with a computer or copy machine, usually with little or no loss in aerodynamic e&ciency!
Do##yists that hae gained some e'perience in constructing and ying from kits and plans will often enture into #uilding custom planes from scratch! "his inoles nding drawings of full si*ed aircraft and scaling these down, or een designing the entire airframe from s cratch! 6t reuires a solid
knowledge of aerodynamics and a plane:s control surfaces! 2lans can #e drawn up on paper or done with CA software! Gany CA packages e'ist for the specic purpose of designing planes and perfecting airfoils!
/edit0Wing location /edit0Digh wing
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"his home#uilt high-wing model is an e'ample of the concept of imple 2lastic Airplane esign where readily aaila#le and easily worka#le materials are used to create a simple, rugged airframe
"he easiest planes to y are typically ones that hae a high wing, or a wing that is on top or a#oe the plane:s fuselage! Wing dihedrals (#end or change of angle in wing relatie to fuselage)
or polyhedrals are also common! Gost trainers and park yers hae this conguration!
"hese planes hold most of their weight under the canopy of the wing structure and tend to react more like a glider! For this reason, they are ery sta#le and easy to y! 6f a high wing plane is out of control, sta#ility can often #e regained #y returning the controls to a neutral position, allowing the plane to naturally fall #ack into a gliding position!
Digh wings are typical of many intage priate planes, such as the 2iper Cu# and the Cessna ;34! /edit08ow wing
"his !?4 cu#ic inch7;4cc glow-powered =inh Puang Godel Gudry CA2 ;4 is a fully aero#atic, low-wing, .sport scale. model plane with slight dihedral
8ow wing planes o%er a higher leel of ying di&culty #ecause the weight of the plane sits on top of the wing structure, making the #alance a #it top heay! Gost wing congurations proide a
slight dihedralto proide a #it more #alance during ight!
"he weight distri#ution and wing position of a low wing plane proides a good #alance of sta#ility and maneuera#ility! "he plane:s moment of inertia a#out the rotation a'is is lower #ecause it is closer to the wing, therefore rolls reuire much less torue and are more rapid than a high wing plane!
8ow wings are typical of World War 66 war planes and many newer passenger planes and commercial $ets!
"his 9lectrify7Ereat 2lanes model of a Jakole Jak-K is an e'ample of a high-performance, fully aero#atic mid-wing plane with no dihedral
Gid-wing planes are usually considered the most di&cult to y! "he wings are usually located right in the ertical middle of the fuselage, near the #ulk mass of the aircraft! =ery little leerage is needed to turn and rotate the plane:s weight!
Gid-wings are often straight without any dihedral proiding an almost symmetrical aerodynamic structure! "his allows the plane to #e relatiely #alanced whether right-side-up, upside-down, or any other position! "his is great for military $ets, sport planes and aero#atic planes, #ut less adantageous for the learning pilot! <ecause of this symmetry, the plane does not really hae any natural or sta#le ying position, like the high wing planes, and will not automatically return to a sta#le gliding position! /edit0um#er of channels
"he num#er of channels a plane reuires is normally determined #y the num#er of
mechanical serosthat hae #een installed (with a few e'ceptions such as the aileron seros, where two seros can operate ia a single J harness (with one of the two seros rotating in the opposite direction))! Ln smaller models, usually one sero per control surface (or set of surfaces in the case of ailerons or a split eleator surface) is su&cient!
Ailerons - controls roll!
9leator - controls pitch (up and down)!
"hrottle or, if electric, motor speed!
Rudder (or =ertical ta#ili*er)- controls yaw (left and right)!
Retracts - controls retracta#le landing gear!
Flaps - 6ncrease lift, #ut also increase drag! Nsing Flaps, an aircraft can y slower #efore stalling! Flaps are often used to steepen the landing approach angle and let the plane land at a
slower touchdown speed (as well as letting the aircraft lift o% at a slower takeo% speed)! 6n #oth cases, aps ena#le using a shorter runway than would otherwise #e reuired!
Au'iliary witches - can control anything such as poilers, Flaperons, 9leons, <om# <ay oors, 8ights, Cameras, etc!
"hree channels (controlling rudder, eleator and throttle) are common on trainer aircraft! Four channel aircraft add aileron control!
For comple' models and larger scale planes, multiple seros may #e used on control surfaces! 6n such cases, more channels may #e reuired to perform arious functions such as deploying retracta#le landing gear, opening cargo doors, dropping #om#s, operating remote cameras, lights, etc!
"he right and left ailerons moe in opposite directions! Doweer, aileron control will often use two channels to ena#le mi'ing of other functions on the transmitter! For e'ample, when they #oth moe downward they can #e used as aps (aperons), or when they #oth moe upward,
asspoilers (spoilerons)! elta winged aircraft designs commonly lack a separate eleator, its function #eing mi'ed with the ailerons and the com#ined control surfaces #eing known as eleons! =-tail mi'ing, needed for such full-scale aircraft designs as the <eechcraft <onan*a, when modeled as RC scale miniatures, is also done in a similar manner as eleons and aperons!
"iny ready to y RC indoor or indoor7outdoor toy aircraft often hae two speed controllers and no seros, as ery small and ine'pensie seros are not yet aaila#le! "here can #e one motor for
propulsion and one for steering or twin motors with the sum controlling the speed and the di%erence controlling the turn (yaw)!
ome !4K> glow models use two controlsQ eleator and rudder with no throttle control! "he plane is own until it runs out of fuel then landed like a glider!
/edit0"urning
"urning is generally accomplished #y rolling the plane left or right and applying the correct amount of up-eleator (.#ack pressure.)!
A three channel RC plane will typically hae an eleator and a throttle control, and either an aileron or rudder control #ut not #oth! 6f the plane has ai lerons, rolling the wings left or right is accomplished directly #y them! 6f the plane has a rudder instead, it will #e designed with a greater amount
of Dihedral Efect , which is the tendency for the airplane to roll in response to sideslip angle created #y the rudder deection! Dihedral Efect in model airplane design is usually increased #y increasing the Dihedral Angle of the wing (=-#end in the wing)! "he rudder will yaw the plane so that it has a left
or right sideslip, dihedral e%ect will then cause the plane to roll in the same direction! Gany trainers, electric park iers, and gliders use this techn iue!
A more comple' four channel model can hae #oth rudder and ailerons and is usually turned like a full si*ed aircraft! "hat is, the ailerons are used primarily to directly roll the wings, and the rudder is used to .coordinate. (to keep the sideslip angle near-*ero during the rolling motion)! ideslip otherwise #uilds up during an aileron-drien roll #ecause of aderse yaw! Lften, the transmitter is programmed to automatically apply rudder in proportion to aileron deection to coordinate the roll!
When an airplane is in a small to moderate #ank (roll angle) a small amount of :#ack pressure: is
reuired to maintain height! "his is reuired #ecause the lift ector, which would #e pointing ertically upwards in leel ight, is now angled inwards so some of the lift is turning the aircraft! A higher
oerall amount of lift is reuired so that the ertical component remains su&cient for a leel turn!
Gany radio controlled aircraft, especially the toy class models, are designed to #e own with no moa#le control surfaces at all! ome model planes are designed this way #ecause it is often cheaper and lighter to control the speed of a motor than it is to proide a moing control surface! 6nstead, .rudder. control (control oer sideslip angle) is proided #y di%ering thrust on two motors, one on each wing! "otal power is controlled #y increasing or decreasing the power on each motor eually! Nsually, the planes only hae only these two control channels (total throttle and di%erential throttle) with no eleator control! "urning a model with di%erential thrust is equivalent to and $ust as e%ectie as turning a model with rudder! 8ack of eleator control is sometimes pro#lematic if
the phugoid oscillation isn:t well-damped leading to unmanagea#le .porpoising.! ee ."oy class RC. section!
/edit0=-tail systems
A =-"ail is a way of com#ining the control surfaces of the standard .U. conguration
of rudder and eleator into a = shape! "hese rudderatorsare controlled with two channels and
mechanical or electronic mi'ing! An important part of the =-"ail conguration is the e'act angle of the two surfaces relatie to each other and the wing, otherwise the ratio of eleator and rudder outputs will #e incorrect!
"he mi'ing works as followsQ When receiing rudder input, the two seros work together, moing #oth control surfaces to the left or right, inducing yaw! Ln eleator input, the seros work opposite, one surface moes to the .left. and the other to the .right. which gies the e%ect of #oth moing up and down, causing pitch changes in the aircraft!
=-"ails are ery popular in 9urope, especially for gliders! 6n the N, the "-"ail is more common! =-"ails hae the adantage of #eing lighter and creating less drag! "hey also are less likely to #reak at landing or take-o% due to the tail striking something on the ground like an ant mound or a rock! /edit02owerplants
Main article: Model aircrat!o"er sources
Gost planes need a powerplant to drie them, the e'ception #eing gliders! "he most popular types for radio-controlled aircraft are internal com#ustion engines, electric motors, $et, and rocket engines! "hree types of internal com#ustion engines are aaila#le #eing small 5 and K stoke engines! Elowplug engines which use nitro-methanol as fuel, compressie ignition (:diesel:) #urn para&n with ethe r as an ignition agent! 8arger engines can #e glowplug #ut increasingly common gasoline is the fuel of choice! /edit0Freuencies and su#-channels
/edit0Freuency
Freuency determines the line of communication #etween a receier and transmitter! "he transmitter and receier must #oth #e on the same freuency so the plane can #e controlled!
/edit0Resered freuencies
Gany countries resere specic freuency #ands (ranges) for radio control use! ue to the longer range and potentially worse conseuences of radio interference, model aircraft hae e'clusie use of their own freuency allocation in some countries!
NA and Canada resered freuency #ands
35 GD*Q aircraft only (France also uses N7Canada channels 5; through +)!
3 GD*Q surface ehicles!
4 V + GD*Q, on the ?-meter #and for all ehicles, with the operator holding a alid amateur radio (FCC in the NA) license!
53 GD*Q general use, toys!
5!K44-5!KM ED*Q pread pectrum #and for general use (amateur radio license holders hae 5!+>-5!K ED* licensed for their general use in the NA) and usually using freuency-hopping spread spectrum RF technology to ma'imi*e the num#er of aaila#le freuencies on this #and, especially at organi*ed eents in orth America!
9uropean resered freuency #ands
+ GD*Q aircraft only!
K4 GD*Q surface ehicles or aircrafts!
53 GD*Q general use, toys, citi*ens #and radio!
5!K ED* spread spectrumQ surface ehicles!
Within the + GD* range, there are designated A and < #ands! ome 9uropean countries allow use only in the A #and, whereas others allow use in #oth #ands!
ingapore resered freuency #ands
5> GD*Q aircraft only
Australian resered freuency #ands
+? GD*Q aircraft and water-craft (odd channels for aircraft only)
5> GD*Q general use
53 GD*Q light electric aircraft, general use
5!K44-5!KM ED*Q pread pectrum #and for general use (ACGA references aaila#le at /K0)
ew Bealand resered freuency #ands
+ GD*Q aircraft only
K4 GD*Q aircraft only
53 GD*Q general use
5> GD*Q general use
+? GD*Q general use
5!K ED* is permitted under BGAA and G97RG regulations, proided euipment #ears a C-"ick compliance la#el
etailed information, including cautions for transmitting on some of the :general use: freuencies, can #e found on the BGAA we#site!
Amateur radio license resered freuency #ands
4 and + GD* in the NA and Canada
K++IK+K GD* in Eermany (some of these Eerman .ham RC. NDF #and channels are also usa#le #y .hams. in wit*erland)
/edit0Channels
Gost RC aircraft in the NA uti li*e a 35 GD* freuency #and for communication! "he
transmitter radio #roadcasts using AG or FG using22G or 2CG! 9ach aircraft needs a way to determine which transmitter to receie communications from, so a specic channel within the freuency #and is used for each aircraft (e'cept for 5!K ED* systems which use spread
spectrum modulation, descri#ed #elow)!
Gost systems use crystals to set the operating channel in the receier and transmitter! 6t is important that each aircraft uses a di%erent channel, otherwise interference could result! For e'ample, if a
person is ying an aircraft on channel + , and someone else turns their radio on the same channel, the aircraft:s control will #e compromised and the result is almost always a crash! For this reason, when ying at RC airelds, there is normally a #oard where ho##yists can post thei r channel ag, so eeryone knows what channel they are using, aoiding such incidents!
A modern computer radio transmitter and receier can #e euipped with synthesi*er technology, using a phase-locked loop (288), with the adantage of giing the pilot the opportunity to s elect any of the aaila#le channels with no need of changing a crystal! "his is ery popular in ying clu#s where a lot of pilots hae to share a limited num#er of channels!
ewer "ransmitters use spread spectrum technology! pread spectrum allows many pilots to transmit in the same #and (5!K ED*) with l ittle fear of conicts! Receiers in this #and are irtually immune to most sources of electrical interference! Amateur radio licensees in the Nnited tates also hae general use of an oerlapping #and in this same area, which e'ists from 5!+> to 5!K ED*!
/edit0Gilitary usage
Radio-controlled aircraft are also used for military purposes, with their primary task #eing
intelligence-gathering reconnaissance! "hese are usually ehicles not designed to contain a human pilot (see unmanned aerial ehicle)! Remotely controlled drone aircraft were used to train gun crews!
eromechanism
From Wikipedia, the free encyclopedia
6ndustrial seromotor
"he grey7green cylinder is the #rush-type C motor! "he #lack section at the #ottom contains the planetary reduction gear, and the #lack o#$ect atop the motor is the optical rotary encoder for position feed#ack! "his is the steering actuator of a large ro#ot ehicle!
A seromechanism, or sero is an automatic deice that uses error-sensing negatie feed#ack to correct the performance of a mechanism! "he term correctly applies only to systems where the feed#ack or error-correction signals help control mechanical position or other parameters! For e'ample, an automotie power window control is not a seromechanism, as there is no automatic feed#ack that controls positionthe operator does this #y o#seration! <y contrast the car:s cruise control uses closed loop feed#ack , which classies it as a seromechanism!
A seromechanism may or may not use a seromotor! For e'ample, a household furnace controlled #y a thermostat is a seromechanism, yet there is no motor #eing controlled directly #y the
seromechanism!
A common type of sero proides position control ! eros are commonly electrical or partially
electronic in nature, using an electric motor as the primary means of creating mechanical force! Lther types of seros use hydraulics, pneumatics, or magnetic principles! eros operate on the principle of negatie feed#ack , where the control input is compared to the actual position of the mechanical system as measured #y some sort of transducer at the output! Any di%erence #etween the actual and wanted alues (an .error signal.) is amplied and used to drie the system in the direction necessary to reduce or eliminate the error! "his procedure is one widely used application of control theory!
peed control ia a goernor is another type of seromechanism! "he steam engine uses mechanical goernorsO another early application was to goern the speed of water wheels! 2rior to World War 66 theconstant speed propeller was deeloped to control engine speed for maneuering aircraft! Fuel controls forgas tur#ine engines employ either hydromechanical or electronic goerning!
2ositioning seromechanisms were rst used in military re-control and marine naigation euipment! "oday seromechanisms are used in automatic machine tools, satellite-tracking antennas, remote control airplanes, automatic naigation systems on #oats and planes, and antiaircraft-gun control systems! Lther e'amples are y-#y-wire systems in aircraft which use seros to actuate the aircraft:s control surfaces, andradio-controlled models which use RC seros for the same purpose!
Gany autofocus cameras also use a s eromechanism to accurately moe the lens, and thus ad$ust the focus! A modern hard disk drie has a magnetic sero system with su#-micrometre positioning
accuracy!
"ypical seros gie a rotary (angular) output! 8inear types are common as well, using a screw thread or alinear motor to gie linear motion!
Another deice commonly referred to as a sero is used in automo#iles to amplify
the steering or #raking force applied #y the drier! Doweer, these deices are not true seros, #ut rather mechanical ampliers! (ee also 2ower steering or =acuum sero!)
6n industrial machines, seros are used to perform comple' motion!
[
mall R7C sero mechanism ;! electric motor
5! position feed#ack potentiometer +! reduction gear
K! actuator arm
RC seros are ho##yist remote control deices seros typically employed in radio-controlled models, where they are used to proide actuation for arious mechanical systems such as the steering of a car, the control surfaces on a plane, or the rudder of a #oat!
RC seros are composed of an electric motor mechanically linked to a potentiometer! 2ulse-width modulation (2WG) signals sent to the s ero are translated into position commands #y electronics inside the sero! When the sero is commanded to rotate, the motor is powered until the
potentiometer reaches the alue corresponding to the commanded position!ue to thei r a%orda#ility, relia#ility, and simplicity of control #y microprocessors, RC seros are often used in s
mall-scale ro#otics applications!
"he sero is usually controlled #y three wiresQ ground, power, and control! "he sero will moe #ased on the pulses sent oer the control wire, which set the angle of the actuator arm! "he sero e'pects a pulse eery 54 ms in order to gain correct information a#out the angle! "he width of the sero pulse dictates the range of the sero:s angular motion!
A sero pulse of ;! ms width will typically set the sero to its .neutral. position or KX, a pulse of ;!5 ms could set it to 4X and a pulse of ;!3 ms to >4X! "he physical limits and timings of the sero
somewhere in the range of >4X - ;54X and the neutral position is almost always at ;! ms! "his is the .standard pulse sero mode. used #y all ho##y analog seros!
A ho##y digital sero is controlled #y the same .standard pulse sero mode. pulses as an analog sero!/+0ome ho##y digital seros can #e set to another mode that allows a ro#ot controller to read #ack the actual position of the sero shaft! ome ho##y digital seros can optionally #e set to another mode and .programmed., so it has the desired 26 controller characteristics when it is later drien #y a standard pulse sero receier!/K0
RC seros are usually powered #y the receier which in turn is powered #y #attery packs or
an9lectronic speed controller (9C) with an integrated or a separate <attery eliminator circuit (<9C)! Common #attery packs are either iCd, iGD or lithium-ion polymer #attery (8i2o) type! =oltage ratings ary, #ut most receiers are operated at = or ? =!
Applications
A compelling adantage of 8i-poly cells is that manufacturers can shape the #attery almost howeer they please, which can #e important to mo#ile phone manufacturers constantly working on smaller, thinner, and lighter phones!
+-Cell 8i2o for RC-models
8i-poly #atteries are also gaining faor in the world of controlled aircraft as well as radio-controlled cars, where the adantages of #oth lower weight and greatly increased run times can #e su&cient $ustication for the price! ome airsoft gun owners hae switched to 8i2o #atteries due to the a#oe reasons and the increased rate of re they proide! Doweer, lithium polymer-specic chargers are reuired to aoid re and e'plosion! 9'plosions can also occur if the #attery is short-circuited, as tremendous current passes through the cell in an instant! Radio-control enthusiasts take special precautions to ensure their #attery leads are properly connected and insulated! Furthermore res can occur if the cell or pack is punctured! Radio-controlled car #atteries are often protected #y dura#le plastic cases to preent puncture! pecially designed electronic motor speed controls are used to preent e'cessie discharge and su#seuent #attery damage! "his is achieed using a low oltage cuto% (8=C) setting that is ad$usted to maintain cell oltage greater than (typically) + = per c ell!
8i-poly #atteries are also gaining ground in 2As and laptop computers, such as Apple:s Gac<ook family, Ama*on:s 1indle, 8enoo:s"hinkpad T+44 and Nltra#ay <atteries, the LPL series of palmtops, the D2 Gini and ell products featuring -#ay #atteries! "hey can #e found in small digital music deices such as i2ods, Bunes, and other G2+ players and the Apple i2hone and i2ad, as well as gaming
euipment like ony:s 2laystation + wireless controllers/50! "hey are desira#le in applications where small form factors and energy density outweigh cost considerations!
