AGUSTA A109 POWER - Graupner · AGUSTA A109 POWER 2 Foreword The A109 POWER is a semi-scale version of the latest version (Type "E") of the established multi-purpose helicopter manufactured

Order No. 4458

GRAUPNER GmbH & Co. KG D-73230 KIRCHHEIM/TECK GERMANYWe reserve the right to introduce modifications ID# 28033 6/04

AGUSTA A109POWER

Fuselage kit for UNI-Mechanics 2000Uni-Expert mechanics or Starlet 50

Warning!The RC helicopter which can be built based from this kit is by no means a toy! It is acomplex flying machine which is capable of causing serious personal injury and damageto property if handled and operated incompetently.You alone are responsible for completing the model correctly and operating it with dueregard for safety. Please be sure to read and observe the enclosed sheets SHW3 andSHW7 which include full safety information. They should be considered as an integralpart of these instructions.

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Foreword

The A109 POWER is a semi-scale version of the latest version (Type "E") of the established

multi-purpose helicopter manufactured by the AGUSTA company.

The original machine has been revised both aerodynamically and functionally, and these

changes have proved useful and positive on the model:

• The drastic reduction in size of the vertical stabilisers compared with the preceding versions

requires less tail rotor power when flying sideways and backwards.

• The retractable undercarriage is now simpler and more robust, and the main legs are

mounted in "sponsons" on both sides of the fuselage. They retract inward, and therefore take

up little of the internal fuselage space.

The white pigmented GRP fuselage requires no bulkheads and is supplied with windows and

other openings machine-cut. The front upper opening is large enough to take the complete Uni-

Expert mechanics or Uni-mechanics 2000 completely assembled (including tuned pipe silencer);

installation is therefore simply a matter of placing the system in the fuselage and fixing it to the

fuselage floor by means of four screws, with a further two supporting screws at the top. The

standard tail rotor drive system is based on a 2 mm Ø spring steel shaft, but a rigid drive system

can be installed as an alternative, as used in the ULTRA-STAR 2000. The system is available

as an optional accessory under Order No. 4451.100.

The mechanically operated retractable undercarriage set is available under Order No. 4458.4; a

separate (low-cost) standard servo is required for each leg, as this makes the set-up and

adjustment process much easier.

As the upper fuselage fairing, the tail cap and the main fuselage are all moulded in high-quality

GRP and finished with a high-gloss white surface, finishing the model only calls for painting the

decorative parts and applying the decal set. The motor is started from above using a hexagon

starter adaptor with freewheel, Order No. 1621; to make use of this facility it is necessary to

install a hexagon starter cone, Order No. 4448.103, in the mechanics cooling fan.

Specification

Length excl. rotors approx. 1525 mm

Width excl. rotor approx. 300 mm

Height approx. 440 mm

Scale 7,5:1

All-up weight min. approx. 5000 g

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Warning notes

• • • • The contents of this kit can be assembled to produce a working model helicopter, but

the model is by no means a harmless plaything. If assembled incorrectly or handled

incompetently or carelessly it can cause serious injury to persons and damage to

property.

• • • • When the model helicopter’s engine is running, the two rotors are spinning at high

speed and contain an enormous quantity of rotational energy. Anything and

everything that gets into the rotational plane of the rotors is either damaged or de-

stroyed - and that includes parts of your body. Please take extreme care at all times

with this machine.

• • • • If any object obstructs the rotational plane of the revolving rotors, severe damage will

probably be caused to the rotor blades as well as the object. Broken parts may fly off

and result in enormous imbalance; the whole helicopter then falls into sympathetic

vibration, you lose control and have no way of predicting what the model will do next.

• • • • You may also lose control if a problem arises in the radio control system, perhaps as

a result of outside interference, component failure or flat or faulty batteries, but in any

case the result is the same: the model helicopter’s response is entirely unpredictable.

Without prior warning it may move off in any direction.

• • • • Helicopters have many parts which are naturally subject to wear, including gearbox

components, motor, ball-links etc., and as a result it is absolutely essential to check

and maintain the model regularly. It is standard practice with full-size aircraft to give

the machine a thorough “pre-flight check” before every flight, and this is equally im-

portant with your model helicopter. Constant checking gives you the opportunity to

detect and correct any faults which may develop before they are serious enough to

cause a crash.

• • • • The kit also includes two additional information sheets - SHW 3 and SHW 7 - which in-

clude safety notes and warnings. Please be sure to read them and keep to our re-

commendations. They are an essential part of these instructions.

• • • • This helicopter is designed to be constructed and operated by adults, although young

people of 16 years or more may do so under the instruction and supervision of com-

petent adults.

• • • • The model features sharp points and edges which may cause injury.

• • • • Flying model aircraft is subject to certain legal restrictions, and these must be obser-

ved at all times. For example, it is essential to take out third party insurance, you must

obtain permission to use the flying site, and you may have to obtain a licence to use

your radio control system (regulations vary from country to country).

• • • • It is important to transport your model helicopter (e.g. to the flying site) in such a way

that there is no danger of damaging the machine. Particularly vulnerable areas are the

rotor head linkages and the tail rotor generally.

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• • • • Controlling a model helicopter successfully is not easy; you will need persistence and

determination to learn the skills, and good hand-eye co-ordination is a basic require-

ment.

• • • • Before you attempt to fly the model you should study the subject of helicopters in

depth, so that you have a basic understanding of how the machines work. Read

everything you can on the theory of helicopters, and spend as much time as you can

watching other model helicopter pilots flying. Talk to chopper pilots, ask their advice,

and enrol at a specialist model flying school if you need to. Many model shops will

also be prepared to help you.

• • • • Please be sure to read right through these instructions before you start work on the

model. It is important that you clearly understand each individual stage of assembly

and the correct sequence of events before you begin building.

• • • • Don’t make modifications to the model’s construction by using parts other than those

specifically recommended, unless you are certain of the quality and suitability of

these other components for the task.

• • • • We have made every effort to point out to you the dangers inherent in operating this

model helicopter. Since neither we, the manufacturer, nor the model shop that sold

you the kit have any influence over the way you build and operate your model, we are

obliged to disclaim any liability in connection with it.

Liability exclusion / Compensation

As manufacturers, we at GRAUPNER are not in a position to influence the way you build

and set up the model, nor how you install, operate and maintain the radio control system

components. For this reason we are obliged to deny all liability for loss, damage or costs

which are incurred due to the incompetent or incorrect use and operation of our prod-

ucts, or which are connected with such operation in any way.

Unless otherwise prescribed by binding law, the obligation of the GRAUPNER company

to pay compensation, regardless of the legal argument employed, is limited to the in-

voice value of that quantity of GRAUPNER products which was immediately and directly

involved in the event which caused the damage. This does not apply if GRAUPNER is

found to be subject to unlimited liability according to binding legal regulation on account

of deliberate or gross negligence.

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Contents

• Foreword ............................................. P.2

• Warning notes ......................................... P.3

• Accessories, extra items required ............................ P.6

• 1. Assembling the model .................................. P.7

• 1.1 Preparation, explanatory notes ......................... P.7

• 1.2 Cutting the access opening for mechanics installation ........ P.7

• 1.3 Installing the main retract units ......................... P.8

• 1.4 Noseleg retract unit ................................. P.11

• 1.5 Installing the mechanics .............................. P.14

• 1.6 Tailskid .......................................... P.15

• 1.7 Tail rotor ......................................... P.17

• 1.8 Horizontal stabiliser ................................. P.20

• 1.9 Installing the silencer ................................ P.20

• 1.10 Completing the upper fuselage fairing and tail cap .......... P.21

• 1.11 Applying a colour finish ............................. P.21

• 1.12 Attaching the windows .............................. P.21

• 1.13 Receiver aerial .................................... P.22

• 1.14 Centre of Gravity .................................. P.22

• 2. Adjustments ......................................... P.23

• 3. Final checks before the first flight .......................... P.26

• 4. Maintenance ......................................... P.26

• 5. Fitting the starter adaptor ................................ P.26

• 6. Adjustments for the first flight, checking blade tracking ........... P.27

• Notes on adjusting the motor ............................. P.28

• 7. General safety measures ................................ P.29

• 8. Some basic helicopter terminology ......................... P.29

The instructionsWe have invested considerable effort in producing these instructions to ensure that you are ableto build and fly your new model helicopter safely and without problems. Whether you are abeginner or an expert, please be sure to follow these instructions, step by step, exactly asdescribed in the text.

• Certain sub-assemblies are supplied completely pre-assembled, including the mechanics,but they still need to be checked and adjusted before use. It is entirely the modeller’sresponsibility to check that all screws and other joints are tight and secure, and to carry outthe essential adjustments thoroughly and conscientiously.

• The process of completing the mechanics is carried out by referring to the illustrations andthe explanatory texts which accompany them.

• The joints marked with this symbol must be secured with thread-lock fluid, e.g.Order No. 952 or bearing adhesive, Order No. 951; be sure to remove all traces of greasebefore applying the fluid.

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Mechanics and accessories (see also Mechanics manual)Recommended Mechanics: Order No. 4448.LN UNI-MECH. 2000 with OS MAX 91 motor Red. ratio 7.7 : 1 Order No. 4448.LN UNI-MECH. 2000 with OS MAX 61 motor Red. ratio 9 : 1 Order No. 4449.RXN, 4450.L UNI-Expert mech. with OS MAX 61 Red. ratio 9 : 1 Order No. 4445, 4446, 4446.SX Starlet 50 with OS MAX 50 motor Red. ratio 10 : 1

Retractable undercarriageOrder No. 4458.4 (a separate servo is required for each undercarriage leg; low-cost standardservos can be used, e.g. C 507, Order No. 3891)

Recommended main rotor blades: Order No. 1246B GRP, reflex 688 mm long Rotor Ø 1551 mm (Starlet: 1533 mm) Order No. 1266 CFRP, symm. 686 mm long Rotor Ø 1547 mm (Starlet: 1529 mm)

DecalsOrder No. 4458.99: dark blue, gold, black, red

AdhesivesUHU plus schnellfest, Order No. 962, fast-setting.UHU plus endfest 300, Order No. 950, slow-setting, for gluing GRP to wood.UHU Blitz, thin cyano-acrylate, Order No. 5803.Thick cyano, Order No. 1101, for tacking parts together.Filler powder, e.g. Order No. 963, for thickening epoxy resin.

Tools required:As a minimum you will need the following items: round, half-round and flat files, set of twistdrills, light-duty tin-snips, fretsaw, various screwdrivers and allen keys and general-purposepliers. Coarse abrasive paper, e.g. 100-grit, Order No. 1068, for roughening joint areas and foradjusting the GRP body shells.

Radio control equipment (see main Graupner catalogue)A radio control system equipped with specialist helicopter options or a micro-computer RCsystem such as the mc-14, mc-15, mc-19, mc-22 or mc-24 is required.

Servos (we recommend high-performance servos) such asC 4421, Order No. 3892

Gyro:PIEZO 5000 gyro system, Order No. 5146, with NES-8700G super-servo, Order No. 5156, orPIEZO 550 gyro system, Order No. 5147, or G490T gyro system, Order No. 5137.

Electronic speed governor:mc-HELI-CONTROL, Order No. 3286

Receiver power supply: For safety reasons it is essential to use a high-capacity receiverbattery; we recommend at least 2000 mAh. You can monitor the state of the battery constantlyby fitting a voltage monitor module, Order No. 3138.

Receiver battery harness: Order No. 3050, suitable receiver battery: Order No. 2568.

Optional components:

Rigid tail rotor drive system, Order No. 4451.100Tail boom with twin-ballraced stainless steel drive shaft and articulated joints front and rear. Youwill also need one tail boom mounting flange, Order No. 1292.5.

Note:If you wish to use the rigid tail rotor drive system in the AGUSTA A 109 POWER please notethat the shaft must be cut to the correct length.

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1. Assembling the model1.1 Preparation, explanatory notesThe numbers in (brackets) refer to the part numbers as printed in the parts list (see end of instructions).

The fuselages are hand-moulded and are likely to exhibit minor variations and irregularities onthe inside, especially along the central joint seam.Good access to the essential parts of the mechanics is provided by the side windows. Beforefinally installing any part check carefully that it fits, trim where necessary and carry out a "dryrun" (without glue). Take your time and work steadily and patiently. All screwed joints exceptthose involving plastic and those with self-locking nuts must be secured with thread-lock fluid;this is a basic rule, and is not mentioned at every stage in the instructions. Where extra itemsand accessory components are used they should be prepared and installed as described in theinstructions supplied with them.

1.1.1 MechanicsIn these instructions we assume that the main mechanical system for the model is alreadycompletely assembled. It is a good idea to remove the silencer and manifold from the motor,and temporarily remove the rotor head from the mast, as this makes it easier to trial-fit and in-stall the system in the fuselage. We recommend the use of the optional silencer console(4450.149) which supports the silencer against the mechanics. To ensure that the motor can bestarted using the hexagon starter adaptor (Order No. 1621) it is essential to install the hexagonstarter cone, Order No. 4448.103, in the cooling fan within the mechanics.The skid attachment brackets 1291.2 must be installed with the recessed hole facing up. Pressan M3 hexagon nut into each recess and secure them with a drop of bearing lock fluid (OrderNo. 951) on the outside. Don’t allow the fluid to run into the threaded section!In recent models of the mechanics the plastic brackets feature moulded-in inserts; in this caseseparate nuts are not required.

1.1.2 FuselageV Glued joints: the GRP parts must be thoroughly roughened at all joint positions using coarseabrasive paper; this is the only way to ensure that the glued joints are really strong and durable.Almost all fuselage openings for windows, cooling air and undercarriage legs are pre-cut, andthe various holes required for other screwed joints are described in the course of the instructi-ons. Where parts have to be glued to the inside of the fuselage it is best to apply the glue usinga long strip of wood or similar tool. All internal wooden parts must be fuel-proofed before in-stallation; a good method is to impregnate them with cyano glue.The upper fuselage fairing (B2) and tail cap (B3) have to be trimmed carefully to obtain a neat fiton the main fuselage moulding (B1). Trim the machined openings in the fuselage wherenecessary, and sand them smooth using fine abrasive paper; leave an even flange all round thewindow openings to support the glazing panels.

1.2 Cutting the access opening for mechanics installationThe windscreen is designed to be removable in a single piece, and this allows the builder to in-stall and remove the whole mechanical system complete with silencer and, if fitted, the tailboom, without any disassembly. The first step is to cut through the horizontal upper screen strutmoulded into the front of the fuselage at left and right, as shown in the drawing. Use a fretsawand take care to cut neatly and in a straight line.

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Glue the two wooden lugs (A15) to the cross-piece as shown, and hold it in its exact originalposition on the fuselage. Drill a 1.5 mm Ø hole through each lug (A15) and into the fuselage,then open up the holes in the lugs alone to 2.2 mm Ø. Cut small pieces of part (A18) to formdoublers and glue them on the inside of the holes in the fuselage to take the fixing screws.Continue the holes through the doublers, then fix the cross-piece to the fuselage by fitting a 2.2x 9.5 mm self-tapping screw on either side.The top screws are concealed by the upper fuselage fairing, and the front joint line by the frontscreen panels which are screwed in place later.Now you can cut through the vertical strut which divides the two front screens, again cuttingcarefully as shown in the drawing. Glue the lug (A19) to the inside of the strut, allowing it toproject at the bottom by about 8 mm. Hold the strut in its exact original position again. Drill a 1.5mm Ø hole right through the bottom part of the strut and the plywood lug. Open up the hole inthe strut to 2.2 mm Ø so that a further 2.2 x 9.5 mm self-tapping screw can be fitted to secure it.

1.3 Installing the main retract unitsThe stub wings moulded into the fuselage are designed in such a way that the main retract units(F1) are a close fit and can be glued directly in place. They should rest squarely against the topsurface, and any space at the bottom between the fuselage skin and the retract unit flange canbe filled with pieces of scrap wood.We do not recommend installing the retract units with screws so that they can be removed. Ifthe undercarriage legs should be damaged they can still be replaced while the mechanism is inthe fuselage; if the worst should happen and the retract unit suffers serious damage, it is likelythat the shock will have broken off the stub wing in any case.he first step is to check the pre-assembled main retract units (F1); ensure that they operatefreely and that all screws are tight; we suggest that you undo each screw in turn, apply a drop ofthread-lock fluid and then re-tighten. Slip the reducer sleeve (F4) onto the undercarriage leg(F2) and insert it in the retract unit mechanism (F1). Tighten the M3 x 3 grubscrew moderatelyto secure the leg for the time being.Cut off the screw heads from two M2 x 20 mm machine screws to form two short threadedpushrods (F6); complete the two pushrods as shown in the drawing and connect the clevises tothe actuating arms of the retract units.

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Now place the retract units in thestub wings which are integral withthe fuselage, as shown in thedrawing. The edge of the sidepanels of the mechanism mustrest flat on the top surface of thestub wing, and should be installedas far outboard as possible.Check this by measuring thedistance from the extended leg tothe outside face of the stub wing;the distance should be about 18mm.

You may find it necessary toround off the corners of the sidepanels of the retract units with afile to allow them to slide into thecorrect position; this compensatesfor the rounded inside corners inthe moulding which are caused bythe manufacturing process.

The retract units should now be adjusted according to the following criteria:

• In the extended state the undercarriage legs (F2) should be parallel to each other whenviewed from the side and the front, and should be vertical relative to the underside of thefuselage.

• With the wheels (F40) fitted, the undercarriage legs should retract as accurately as possibleinto the machined wheel wells, so that as little trimming as possible needs to be done to thefuselage openings.

• When retracted the wheels should lie completely inside the fuselage; if the undercarriagelegs are parallel to each other when extended this will normally be right automatically.

Tack the retract units in place with a few drops of UHU plus schnellfest (5-minute epoxy) andcheck when the resin is hard that they are in exactly the correct position. Mix up some thickenedUHU plus endfest 300 (slow-setting epoxy) and apply it all round the retract units where theymeet the fuselage, preferably in two stages:Start with the fuselage resting inverted on the workbench, and glue the retract units to the topsurface of the stub wings by applying plenty of resin in the angle between the fuselage skin andthe outside of the retract unit side panels.Take care! No glue must be allowed to get onto the moving parts of the retract unit mechanism!!When the resin has set hard turn the fuselage over and repeat the process, this time gluing theretract units to the underside of the fuselage. Any gaps should be filled with scrap pieces ofwood and sealed with plenty of UHU plus endfest 300. Don’t push the packing pieces in toofirmly, or you will distort the fuselage moulding.

Note: the glued joints simply prevent the retract units moving inside the stub wings. Thecompressive loads which occur during landing are transmitted directly to the top surface of thestub wings due to the method of installation..

When the retract units have been permanently installed in the fuselage the undercarriage legs(F2) and reducer sleeves (F4) should be withdrawn from the mechanisms (F1) by loosening thegrubscrews. Apply plenty of bearing lock fluid 603 (Order No. 951) to the sleeves, slide them onthe undercarriage legs again and then fit them in the retract units. Align the legs carefully, thenapply a drop of bearing lock fluid 603 to the grubscrews and tighten them fully.

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Assemble two servo consoles from the woodenparts (A7) and (A8) and mount the retract servosin them as shown in the drawing.

Note that the two units should look exactly thesame, i.e. not a mirror-image pair; otherwise youwill find that the retract units will operate inopposition, i.e. one down, one up, instead of bothtogether, when you connect the two servos to thereceiver using a Y-lead.

Attach a linkage ball to each servo output arm asshown in the drawing.

Now place the servo consoles in the fuselage and press the links on the pushrods onto thelinkage balls attached to the servo output arms. Position the servo consoles with their L-shapedside panels resting against the top surface of the stub wing and the fuselage side. Check thatthe pushrod runs perpendicular to the servo and does not jam when operated. Tack the servoconsoles in place with a few drops of UHU plus schnellfest.

To adjust the function of the retract systems you will need to connect the servos to the receiverusing a Y-lead: with Graupner radio control systems the servo travel should be set to 100% inboth directions, and the retracts will be controlled with a toggle switch. First adjust the pushrodand servo arm position with the undercarriage extended, with the aim of ensuring that theundercarriage leg is securely latched mechanically without the servo being stalled. When youare satisfied, retract the undercarriage and check that it also locks mechanically in the retractedposition without stalling the servo. You may find it necessary to adjust the length of the pushrodand/or the servo output arm in order to achieve complete success. When you are satisfied, gluethe servo consoles permanently to the fuselage using UHU plus endfest 300.

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1.4 Noseleg retract unit1.4.1 Assembling the bulkhead frameworkAssemble the framework from parts (A1) ... (A6) and (A11) as shown in the drawing. Checkcarefully that all the parts are positioned and aligned correctly before gluing the joints. Thebracket for the actuating arm (F24), consisting of parts (A5) and (A6), must be attached to theinside of the left-hand fore-and-aft bulkhead (A1).

1.4.2 Assembling the noseleg unitFirst fit the spring (F22) on the moulded-in spigots between the two arms (F23) and fix the armstogether using two M2 x 10 screws and M2 nuts. Apply a drop of cyano glue to the wheel halves(F40) - one has a tongue, one a groove - and press them together.

Fit one of the threaded sleeves (F19)through the fork sections (F20) andslip the second sleeve (F19) throughthe wheel hub. Insert the four M2 x 8screws and tighten them to join thefork sections together.

The spring (F22) must be undertension when the undercarriage legand wheel fork are assembled. Holdthe wheel fork over the leg in such aposition that the 2 mm Ø holes are inline and press a dowel pin (F9)through to form the pivot shaft.

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1.4.3 Fitting the buffers*The two buffers (F30) for the undercarriage fork can now be fixed to the undercarriage leg withcyano as shown in the drawing. Note that they must be located on the flat surface, and shouldrest against the shoulder of the undercarriage leg at the top of its travel. When the glue has sethard press the undercarriage fork up as far as it will go against the spring tension, as shown inthe drawing.

When the model is completed and ready to fly you will find that the nosewheel always restsagainst its buffers when the model is on the ground; the spring only serves to move the wheel tothe position required for retraction once the model has lifted off.

1.4.4 Installing the noseleg retract unit in the frameworkGlue the large bushes (F25) in parts (A1) and (A6) and check that they are exactly in line. Slipthe following parts on the aluminium tube (F29) in turn: first, on the inside, the lever (F24) withthe actuating pin (F3) pressed into it as shown, then a collet (F26) between (A1) and (A6), thenthe second lever (F24) on the outside of (A1) followed by a further collet (F26). Attach the brasslinkage ball for the pushrod to the second of the levers (F24), using the second hole from theinside.

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Mount the noseleg assembly on the shaft (F28); it is supported by the small flanged bushes(F27), which are glued to the inside of (A1) and (A2) and must be in line. Since the undercar-riage is narrower than the support system you will need to fit the spacer sleeves (F41) on bothsides. Install the undercarriage leg and engage the actuating pin (F3) in the slot in part (F23) asyou do so.

1.4.5 Noseleg retract linkagePlace the servo in the opening in (A1) as shown in the drawing, and screw it in place. Make upthe retract pushrod from two ball-links 4618.5 and the threaded rod (F31); the distance betweenthe links should be about 23 mm (see drawing). Select a servo output arm which allows you toscrew a linkage ball on its inside face (facing the servo) at a point 20 mm from the servo outputshaft axis. Fix the ball in place between the output arm and the servo.Position the actuating lever (F24) as shown in the drawing and temporarily tighten thegrubscrews in the collets (F26). Connect the servo to the receiving system, using the samechannel and set-up as previously used for the main undercarriage.Note: the same channel is used for all three retract servos, which means that any electronicadjustments (centre, travel etc.) you make at the transmitter will affect all three servossimultaneously. For this reason it is necessary to adjust each retract unit and servo separatelyso that it retracts and extends reliably using exactly the same settings as the other two. Theunits must lock reliably at each end-point, and must not stall the servo.Move the retract switch on the transmitter to the "undercarriage extended" position and fit theoutput arm on the servo as shown in the drawing. Connect the pushrod. The noseleg unitshould now be securely locked in the extended position, with the pin (F3) right at the end of theslot in the undercarriage leg, but without placing a load on the servo.

Now retract the undercarriage. In its retracted position the nosewheel should also be lockedmechanically, although in this case it does not matter if there is a slight gap between the pin(F3) and the end of the slot, as the forces are much lower at this end-point. The crucial point is

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that the retract unit should lock reliably in the extended state; adjust the pushrod and leverscarefully to ensure that this is the case. Do not alter the servo travel at the transmitter, as thiswould undo all the adjustments you have already carried out on the main retract units.Once you have found the correct position of the lever (F24), tighten one of the two grubscrewsin each of the two collets (F26) fully, then unscrew the other one and drill through the threadedhole using a 2.4 mm Ø bit, cutting right through the shaft of the lever (F24) and into thealuminium tube (F29). Repeat the procedure with the grubscrew on the other side. Apply a dropof thread-lock fluid to the grubscrews and screw them in to the point where they engage in thewall of the aluminium tube (F29), and thereby reliably prevent the lever rotating on the shaft.Check once more that the system works reliably and smoothly. It is now ready to be installed inthe fuselage.

1.4.6 Installing the noseleg retract assembly in the fuselageTrial-fit the noseleg assembly in the front of the fuselage; it must be possible for the nosewheelto extend and retract through the pre-cut opening, although it is permissible to trim the openingslightly. You may also need to trim the two fore-and-aft bulkheads (A1) and (A2) to compensatefor any irregularities in the inside face of the fuselage so that the parts fit as snugly as possible,without local pressure deforming the fuselage shell. Set the assembly exactly central and locatethe pre-cut 3 mm Ø holes in the bottom of the fuselage; mark their position on the underside of(A11). Remove the noseleg assembly and drill 3 mm Ø holes at the two marked points.Carefully sand the inside surface of the fuselage perfectly flat where part (A11) meets it (centreseam). Now glue the entire frame in the fuselage shell using UHU plus endfest 300; apply agenerous amount of epoxy to the underside of part (A11) when you do this. Fit two M3 screwsthrough the holes in the fuselage and part (A11) and secure with nuts to ensure that theassembly is correctly positioned. Check that the nosewheel can be extended and retractedreliably before the glue has set hard.

1.5 Installing the mechanics1.5.1 Screwing the mechanics to the bottom of the fuselageDrill two 3 mm Ø holes at the marked points in the rear mechanics support (A12). Place thesupport loosely in the fuselage (bevelled corners to the rear) and check that it is possible toalign the two rear 3 mm Ø holes in the fuselage bottom with the holes in the support (A12). Markthe position of (A12) on the fuselage bottom and carefully sand back the joint surface (centreseam) of the fuselage at that point. Glue part (A12) in place using UHU plus endfest 300,holding it in place with M3 screws and nuts while the glue is hardening.Glue stacks of five parts (A13) together to form blocks 10 mm high. Drill a central 3 mm Ø holethrough each block, taking care to hold the drill exactly vertical.

1.5.2 Screwing the mechanics to the top of the fuselageDrill 2.2 mm Ø holes in the upper mechanics braces (A14R/L) at the marked points. Fit 2.2 x 9.5mm self-tapping screws through these holes from the rear and fit the two brackets (B5) on them,with the recessed holes in the brackets on the outside.

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The two assemblies can now be screwed to the top attachment points on the mechanics usingM3 x 16 socket-head cap screws fitted through the brackets (B5). Don’t mix up the right and leftparts!

1.5.3 Installing the mechanicsFirst ensure that the epoxy used to secure the front framework and the rear mechanics supportin the fuselage has cured completely, then remove the temporary M3 locating screws in themechanics support. Retract all three wheels and place the fuselage flat on its bottom. It isimportant to leave the model in this position for the next stage so that the fuselage mouldingcannot be distorted. Place the main mechanics in the fuselage and secure the assembly withfour M3 x 25 socket-head cap screws which are fitted from the underside through the holes inthe fuselage shell and the wooden supports. Note that you must fit a block consisting of parts(A13) between each support plate and the skid attachment brackets. The top braces (A14 R/L)should now rest against the rear angled face of the upper fuselage cut-out. Adjust the position ofthe mechanics until the main rotor shaft is exactly central where it exits the fuselage at the topwhen viewed from the front, and with the mechanics in this position drill 1.5 mm Ø pilot-holesthrough the braces (A14) and the flange of the fuselage cut-out. Fit a 2.2 x 6.5 mm self-tappingscrew on each side to hold the braces in place temporarily. Now place the upper fairing (B2) onthe fuselage and check that the main rotor shaft is located exactly in the centre of the circularopening in the fairing; make any adjustments required.When you are sure that everything fits correctly, undo the self-tapping screws in parts (A14) andloosen the lower retaining screws in the mechanics to the point where you can apply epoxy(UHU plus endfest 300) between the blocks (A13) and the support plates. Tighten the screwsagain. Undo the M3 socket-head cap screws so that you can remove the top braces, thenthoroughly roughen up the joint surfaces of the fuselage where they meet parts (A14). ApplyUHU plus endfest 300 to the braces and install them permanently, using the self-tapping screwsagain to ensure that the parts are correctly located.

Allow the epoxy to cure completely before undoing the six retaining screws and removing themechanics from the fuselage again.

1.6 TailskidBend the tailskid (B12) to the shape shown in the drawing from the 3 mm Ø spring steel supp-lied, and sand the front third of it to provide a key for the epoxy. Drill a hole in the underside ofthe lower vertical stabiliser, slip the skid into the hole and fix it in place with plenty of UHU plusendfest 300; the glue can be applied through the rear fuselage opening on a strip of scrapwood.

Work carefully and conscientiously here, as access to the joint is impossible once the tail rotorbulkhead has been installed.

While the glue is still soft, carefully align the tailskid so that it follows the curvature of the frontedge of the vertical stabiliser. The skid should continue the line of the decal which is appliedlater.

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1.7 Tail rotor1.7.1 Installing the tail rotor assemblyGlue together the three parts (A9) to form the tail rotor bulkhead, and when the glue is hard trimthe bulkhead to fit in the tail end of the fuselage. Fix the tail rotor gearbox to the bulkhead withthree 2.9 x 13 mm self-tapping screws, then slip the assembly into the fuselage.

The tail end of the fuselage features an all-round recessed flange which accepts the tail cap(B3). Cut a semi-circular recess in one side of the flange to provide clearance for the tail rotorhousing. Check that the tail rotor bulkhead with the gearbox attached can be fitted into thefuselage to a depth of about 7 mm.Set the tail rotor shaft exactly horizontal, and check that the tail rotor bulkhead is parallel to therear face of the fuselage (check the distance between the bulkhead and the edge of themoulding top and bottom). Tack the tail rotor bulkhead in this position with a little cyano, thenreinforce the joint by applying UHU plus endfest 300 carefully all round. It is essential to applyepoxy to the inside of all joints too, using a strip of wood as a tool.

1.7.2 Tail rotor drive systemThere are two options for the tail rotor drive system:

1. The conventional drive system is based on a 2 mm Ø steel rod shaft (B9), running in aplastic sleeve (B8) which in turn is supported in the channeled balsa rail (B6); this version isrecommended, and the parts are included in the kit.

2. As an alternative you can install a rigid tail rotor drive system as used in the ULTRA-STAR2000 and other models, and this is available as an accessory under Order No. 4451.100. Inthis case power is transferred via a 6 mm Ø stainless steel tube which runs in severalballraces inside a 20 mm guide tube. The tubular shaft is connected front and rear by meansof articulated joints.If you intend to install this system in the Agusta note that the tail boom and the drive shafthave to be shortened. Details of the installation are left to the builder’s discretion; we do notinclude details of it here.

1.7.3 Tail rotor drive system using 2 mm Ø steel rod shaftTrim the support former (A10) to fit in the tail end of the fuselage and glue it in place using UHUplus endfest 300. Note that the large opening (for the tail rotor pushrod ) must be on the left, asseen from the tail looking forward.

1.7.3.1 Cutting the tail rotor shaft to lengthInstall the mechanics in the fuselage. Slide the quick-release sleeve 4618.58 along the tail rotordrive shaft (B9) to the point where the shaft’s pre-formed end is located inside the sleeve; slipthe collet 56.0 with grubscrew (loose for the moment) on the shaft. Fit the shaft and sleeve inthe fuselage working from the rear. Slip the pre-formed shaft (B9) into the yoke 4648.57 of thequick-release coupling and push the sleeve along to the end to engage the coupling. Push theshaft into the yoke as far as it will go and mark the length of the shaft at the exact point where itexits the tail rotor bulkhead. The actual required length of the shaft will now be about 15 mm

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less than the marked length. There must be about 1 mm clearance in the yoke at the front end,and at the tail end you have to take into account the length of the tail rotor unit (25.5 mm),measured from the mounting flange, and the depth of the socket in the coupling section 4618.40(about 11.5 mm). The length of the tail rotor drive shaft on the prototype is 826 mm.Now remove the shaft and cut it to length, taking care not to bend it when cutting. Removerough edges from the end of the shaft.

1.7.3.2 Installing the drive shaft support railCut the channeled rail (B6) to a length of 550 mm (keep the waste piece!). Cut the guide tube(B8) which forms the shaft bush to a length of 600 mm. Cut two rings of fuel tubing (suppliedwith the mechanics) about 3 mm long and push the rings onto the sleeve, then slip the sleeveonto the shaft (B9).

Now place the shaft sleeve in the channeled rail and slide the fuel tubing rings up against theends of the rail so that they clamp it in position. Wind a strip of adhesive tape round the ends ofthe channeled rail so that the sleeve cannot fall out of the channel. Now slip this assembly intothe tail boom of the fuselage from the front, past the mechanics, until the tail rotor drive shaft(B9) projects at the rear end far enough to be fixed in the coupling 4648.40 of the tail rotorgearbox. Tighten the screws temporarily, then slide the assembly forward again and engage thefront end of the shaft in the quick-release coupling.Check the shaft length as follows: when the tail rotor is resting flat on the tail rotor bulkhead (A9)there must be at least 1 mm clearance between the end of the shaft (B9) and the end of thesocket in the front coupling yoke.

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Slide the channeled rail (B6) aft until the distance between its front edge and the quick-releasesleeve is about 160 mm.Trim the cross-strut (B7) (the remainder of the channeled rail) to fit in the fuselage under thefront edge of the channeled rail (B6). Tack the strut to both sides of the fuselage with a drop ofthin cyano. Caution: take care that it does not force the fuselage out of shape.When viewed from above the tail rotor drive shaft (B9) must run in a perfectly straight line to thecoupling yoke 4618.57. Viewed from the side it should describe a gentle, even curve. The shaftshould appear to be exactly vertical when seen from the tail rotor support bulkhead.Remove the tail rotor drive shaft assembly from the fuselage again.

1.7.3.3 Final installation of the tail rotor drive systemIn the two preceding sections you have already assembled and trial-fitted the tail rotor drivesystem, so you can now be confident that the parts fit, and that you know their correct location.Withdraw the tail rotor drive shaft (B9) from the sleeve (B8), oil it lightly where it runs inside thesleeve, and slip it back in again.Apply a few drops of UHU plus endfest 300 to both ends of the channel in the channeled rail(B6) and at intervals of about 60 mm along its length. Place the sleeve (B8) in the channel androtate it so that the glue is distributed evenly round the channel.

Fit the assembly in the tail end of the fuselage again, as already described under 1.7.3.2(slipping it past the mechanics), and allow the tail rotor drive shaft to project at the rear to thepoint where it can be screwed in the coupling 4618.40 of the tail rotor gearbox. Carefully removeall traces of grease from the rear end of the tail rotor drive shaft (B9), sand it thoroughly in afore-and-aft direction, push it into the shaft coupling as far as it will go and tighten thegrubscrews in the shaft coupling to fix the shaft in this position. This procedure is important: firstunscrew and remove the grubscrews from the coupling, then apply a little thread-lock fluid,Order No. 952, or bearing lock fluid, Order No. 951, to the threaded holes. Fit the grubscrewsagain and tighten them fully. Even better: file a small flat in the side of the shaft at the pointwhere the grubscrews engage, and tighten the screws down onto the flattened surface, as thisgives the screws something to grip and produces a more secure joint.Insert the shaft and the throat of the tail rotor gearbox into the fuselage from the rear, andengage the shaft (B9) in the quick-release coupling at the front; fix the tail rotor gearbox to itsbulkhead using the three 2.9 x 13 mm self-tapping screws. Check the length of the shaft (B9)once more, i.e. ensure that the clearance in the front coupling yoke is still present.Apply plenty of UHU plus endfest 300 at the point where the channeled rail (B6) passes throughthe bulkhead (A10), and where it rests on the cross-strut (B7) at the front. Rotate the channeledrail so that the channel is on top and slide it into the correct position, resting on the front cross-strut (B7).While the glue is still soft rotate the tail rotor a few times so that the tail rotor shaft and thebearing sleeve align themselves naturally in the position which places them under least stress.Allow the epoxy to set hard, then apply plenty of UHU plus endfest 300 to the two supports(A20) and position them over both ends of the cross-strut (B7) as shown in the drawing. Pressthem against the fuselage sides and leave the epoxy to set hard.Position the collet 56.0 about 1-2 mm aft of the union sleeve and tighten the grubscrew.

1.7.4 Tail rotor control linkageThe tail rotor control linkage is based on a cantilever carbon fibre pushrod. The tail bulkhead(A9) features an opening through which the pushrod can move the tail rotor to either end-pointwithout fouling the edges. The output arm of the tail rotor servo must point down, as describedin the mechanics instructions.

Screw a ball-link onto each of the threaded pushrods (B11) to a depth of about 7 mm. Cut downthe carbon fibre tube to a length of 825 mm and glue the threaded rods (B11) into each endusing UHU-plus endfest 300. Note that the ball-link at the front end should butt up against the

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end of the carbon fibre tube (B10). At the tail end the threaded rod (B11) should be positionedas shown in the drawing, giving an overall length between ball centres of 888 mm.

1.8 Horizontal stabiliserThis assembly is shown in the drawing: for each side cut out one lower and one upper plasticshell (C1/C2) along the marked lines and sand the joint lines absolutely flat. The joint seam lieson the centreline of the airfoil section. It is important that the panels should fit togetheraccurately.Drill 2 mm Ø holes in the die-cut ribs (A16) and (A17) at the marked points to take the supportrods. Glue one rib (A16) and one rib (A17) in each bottom stabiliser shell using Stabilit Express,in the position shown in the drawing. Glue the upper shells on top and clean up the joint seams.If you work carefully the surfaces can be left unpainted; all that is required is a light rub withpolishing compound. Otherwise fill any gaps, sand smooth and apply a painted finish.You will find the hole positions for the support rods (B13) already marked on the fuselage; drill 2mm Ø holes at those points. After painting slip the rods through the holes in the fuselage andthread the stabiliser panels onto the ends. Epoxy the panels to the support rods and thefuselage sides.

If you have installed the rigid tail rotor drive system you will find that the support rods cannot beinstalled full-length across the fuselage without fouling the internal tail boom. In this case cut therods down so that they project out of the stabiliser root ribs by only about 5 mm, then glue thepanels to the fuselage using UHU plus endfest 300. Take care to glue the joints soundly.

1.9 Installing the silencerThe basic rule is that the silencer must be installed in such a way that it does not touch thefuselage at any point, otherwise the result will be extra vibration (and noise), and excess heatcould even damage or distort the fuselage moulding. For these reasons the silencer must beinstalled with particular care.If you are using one of the recommended rear-exhaust two-stroke motors the end of themanifold will be located centrally below the mechanics, and the silencer can be attached to themanifold using the usual Teflon exhaust hose and spring clips. At the rear end we recommendfitting the silencer console (4450.149) to provide further support. The console braces thesilencer firmly in position relative to the mechanics, and this makes it much easier to removeand install the mechanical assembly for maintenance work. The console has to be installed insuch a way that it suits the requirements of the model, i.e. so that the silencer tail pipe can beextended with a short piece of silicone hose and run out of the fuselage through a hole ofminimum size.You may find it helpful to bend the rear end of the tail pipe slightly, although a better solution isto use an angled silicone exhaust hose, Order No. 1383.10.

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1.10 Completing the upper fuselage fairing and tail capCheck that the upper fuselage fairing (B2) is a snug fit and attach it to the fuselage using nine2.2 x 6.5 mm self-tapping screws: two screws left and right at the bottom of the "doghouse",three further screws on each side and one screw at front centre.

Cut out the spoiler (B4) from 2 mm thick ABS and position it in the fuselage fairing (B2) asshown, with its circular opening aligned with the swashplate cut-out. Set it parallel to thefuselage centreline as seen from above, and glue it to the upper fuselage fairing (B2) only usingcyano.When the glue has set hard bend the rear end of the spoiler (B4) down to follow the shape ofthe "doghouse" and fix it to the fuselage at the marked point with a 2.9 x 16 mm screw.

For routine maintenance work you must remove the rotor head before undoing the upperfuselage fairing (B2); the fairing can then be lifted off complete with the spoiler (B4).

Cut all round the marked line on the tail cap (B3). Cut out an opening on the left-hand side toclear the tail rotor gearbox and the tail control lever. Fix the cap to the recessed flange usingthree 2.2 x 6.5 mm self-tapping screws.

1.11 Applying a colour finishThe quickest, neatest and simplest method of achieving an attractive finish on your helicopter isto use the decal sheet available as an accessory. Apply the decals using the kit box illustrationas a guide. For a true scale appearance you should first paint the black area around thewindows and the dark blue top edges to the vertical stabiliser and "doghouse", using paints fromthe Universal or Acrylfix ranges. To ensure that the paint adheres well to the fuselage rub downthe surfaces beforehand using fine wet-and-dry paper (600- to 1200-grit).

1.12 Attaching the windowsThe individual glazing panels are supplied in the kit pre-cut. Nevertheless please check eachone carefully and trim the edges as necessary. The front screens are fixed permanently to theremovable front section of the fuselage, and are best attached to the fixed part of the fuselageusing 2.2 x 6.5 mm self-tapping screws. We also recommend that you leave the large sidewindows in both rear side doors removable to provide easy access to the needle valve,receiving system switch and other components of the mechanics. The fixed windows can beattached to the fuselage using UHU plus endfest 300 or cyano. Caution: be sparing with theadhesive as any excess squeezed out will spoil the appearance of the glazing.Each of the removable side windows can be fixed to the window frames using four 2.2 x 6.5 mmself-tapping screws, fitted as shown in the drawing.

After drilling the screw-holes in the glazing panels open up the holes outwards to form open-ended slots. Don’t tighten the screws fully; instead tighten them just to the point where thepanels can be slipped under the screw heads by gently bending them inwards. They can beremoved in the same way. Fit internal doublers (F18) for the removable window screws asalready described.

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The window set also includes the two dummy exhausts moulded in clear smoked-tint plastic.Cut them out leaving a flange about 8 mm wide all round, and open them up at the ends. Youcan achieve a very realistic impression by painting the inside of the exhaust pipes with anairbrush or spray can; start with a thin (non-covering) copper colour, then silver, and finally mattblack.The completed exhaust pipes can then be glued in the pre-cut openings in the top of thefuselage. Trim the openings carefully to obtain a close fit, and glue the pipes in place from theinside.The corrugated imitation air inlet grilles can simply be glued in the recesses moulded into thefuselage (don’t cut openings for them!), after applying a light coat of silver spray paint to thebase surface. The silver shows through the smoked dummy grilles to give a realistic semi-scaleimpression of a well-used turbine air inlet. Cut out the vacuum-moulded instrument console allround along the marked line, and cut out the front face at the same time. Paint the console mattblack and apply the instrument decal. Place the console centrally on the fore-and-aft bulkheads(A1) and (A2) and fix it to (A3) with a 2.2 x 6.5 mm self-tapping screw.

1.13 Receiver aerialThe receiver aerial should be deployed as follows:You will find slots in the sides of the battery console through which cable ties can be fitted toretain a plastic guide tube (Order No. 3593) in which the aerial can reside. Slip the aerial in thetube and arrange it as follows: fix one end at front right and then run it forward in as broad acurve as possible through the nose of the fuselage, then to the left-hand side of the batteryconsole (fix it there with a cable tie), then back along the mechanics sub-structure and finally upto a point below the fan housing. Attach the tube to the mechanics using additional cable ties asrequired.

The advantage of this method of aerial deployment is twofold: on the one hand the aerial is fixedto the mechanics only, and therefore forms a compact unit which can be installed and removedeasily; on the other hand it is well clear of any mechanical components which could radiateelectrical noise, and forms an efficient receiving plane in all directions.

1.14 Centre of GravityThe Centre of Gravity should be located 0 - 5 mm in front of the forward edge of the main rotorshaft; you may need to install lead ballast to achieve this. To check the CG set the rotor bladesat right-angles to the fuselage centreline, raise the helicopter by the blade holders and tip it onits side through 90°: if the CG is correct, the nose of the helicopter will now swing slowlydownwards.

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2. Setting upThe following sections can be found in the same or a similar form in the manuals of themechanics. They are included here, too, if the mechanics used to be combined with thisfuselage kit is one of the older UNI-EXPERT-Mechanics, fitted with the older plans.

2.1 Setting up the cyclic control systemThe basic settings of the roll and pitch-axis control systems should already be correct if youhave fitted the pushrods exactly as described in these instructions. The pushrod linkage pointson the servo output arms are pre-defined, so any servo travel adjustment required must becarried out via the transmitter’s electronic adjustment facilities. Please note that servo travelmust not be set at too high a value; the swashplate must not foul the main rotor head when theroll and pitch-axis stick is at its end-points, as this would mean that smooth collective pitchcontrol would no longer be possible, since the swashplate could not move any further along theshaft.

2.2 Main rotor collective pitch settingsThe collective pitch values are measured using a rotor blade pitch gauge (not included in thekit). The following table shows good starting points; the optimum values may vary according tothe rotor blades you are using and the model itself.

Minimum Hover MaximumHovering, practice flying -2° 5,5°...6° 12°Aerobatics -4° 5°... 5,5° 8°... 9°Auto-rotation -4° 5,5° 13°The collective pitch settings are adjusted at the transmitter. This is the procedure:1. Measure the setting for hovering collective pitch and set it correctly;2. Measure collective pitch maximum and minimum, and adjust the values using the collective

pitch adjustment facility on your transmitter, following the diagrams shown below:

2.3 Adjusting the carburettor control systemThe following diagrams show two possible carburettor control curves:

• The hover-optimised throttle curve produces smooth, gentle control response in the hoveringrange.

• The values stated here vary greatly according to the motor, fuel, silencer etc. you are using.The only means of establishing the ideal settings is to carry out your own series of practicaltest-flights.

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2.4 Further adjustmentsIf you have made up all the linkages exactly as described in the previous sections, no changesto the mechanical arrangements will be necessary. The following adjustments can all be carriedout at the transmitter:1. Servo direction

Set the "sense" (direction of rotation) of all servos as stated in the instructions. Check thethrottle servo in particular!

2. Dual-RatesYou can set switchable travels for roll, pitch-axis and tail rotor. As a starting point werecommend 100% and 75% as the two settings.

3. ExponentialFor the basic set-up you should leave all control systems set to "linear".

4. Sub trimDo not make any adjustments to this point. At a later stage you may wish to make minorcorrections here.

5. Adjusting servo travel This is where you can adjust the maximum servo travel. Note that the travels should alwaysbe the same on either side of neutral, otherwise you will end up with unwanted differentialeffects:

For the throttle and swashplate servos (collective pitch function) it is important to check thatservo travels are symmetrical, i.e. with the same values for both directions, and that thethrottle servo can move the carburettor barrel from the completely closed position (motorstopped) to full throttle, without being mechanically stalled at any point. The collective pitchfunction of the swashplate servos should produce a range of blade pitch angles covering -5°to +13°, also with symmetrical travels; you may find it necessary to remove the servo outputarm, move it round by one spline and fit the retaining screw again.

The mechanics should now be set up virtually perfectly. When the throttle/collective stick isat centre (hover point) collective pitch should be about 5.5°, and the carburettor barrel shouldbe half-open.Note:The collective pitch and throttle curves can be adjusted later to meet your exact personalrequirements. However, if you have already set differential travels in the basic set-upprocedure, as shown in diagram "B" above, any fine adjustments required subsequently willbe more difficult!

6. Collective pitch and throttle curvesThese adjustments are of fundamental importance to the flight performance of any modelhelicopter. The aim of the procedure is to maintain a constant rotor speed when the model isclimbing and descending, i.e. regardless of load. This then represents a stable basis forfurther fine-tuning, e.g. of the torque compensation system etc. (see also P. 21, collectivepitch and throttle curves).

7. Static torque compensationThe tail rotor servo is coupled to the collective pitch function via a mixer in the transmitter inorder to compensate for torque changes when you operate the collective pitch control. Onmost transmitters the mixer input can be set separately for climb and descent.Recommended values for the basic settings are: climb: 35%, descent: 15%.

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8. Gyro adjustmentGyro systems damp out unwanted rotational movements around the vertical (yaw) axis of themodel helicopter. They do this by detecting the unwanted motion and injecting acompensatory signal into the tail rotor control system, and in order to achieve this effect thegyro electronics are connected between the tail rotor servo and the receiver. Many gyrosystems also allow you to set two different values for gyro effect and switch between themfrom the transmitter via a supplementary channel. Some gyros even offer proportionalcontrol. The extra channel is controlled via a proportional slider or rotary knob, or a switch,depending on the gyro system.

If your gyro system features an adjustor box with two rotary pots for two fixed settings, andyou can switch between them from the transmitter, it is best to set one adjustorapproximately to centre (50%), and the other to 25%. If the gyro system providesproportional control between the two set values, then the one pot should be set to "0", theother to about 80%.

If you have a gyro system whose effect cannot be adjusted from the transmitter, i.e. there isonly a single adjustor on the gyro electronics itself, the pot should be set to 50%effectiveness as a starting point.

Check that the direction of the gyro’s compensatory action is correct, i.e. that it responds to amovement of the tail boom with a tail rotor response in the opposite direction. If this is not thecase, any yaw movement of the model would be amplified by the gyro! Most gyro systemsare fitted with a change-over switch which reverses its direction, and this must then bemoved to the appropriate position. However, some systems have no such switch, and in thiscase the solution is to mount the gyro inverted.

One factor which all gyro systems have in common is that flight testing is necessary in orderto establish the optimum settings, as so many different influences affect the settings.The aim of the gyro adjustment process is to achieve as high a level of gyro stabilisation aspossible, without the gyro causing the tail boom to oscillate.

Notes regarding the use of the Graupner/JR „PIEZO 450...5000" piezo gyro system inconjunction with a computer radio control system (e.g. mc-12 ... mc-24)The advanced design of this gyro system necessitates a different set-up procedure to the onedescribed above. Please keep strictly to this procedure:1. 1. Set the servo travel for the tail rotor channel to +/-100% at the transmitter.2. If you have a gyro mixer („Gyro-Control“) which suppresses gyro gain when you operate the

tail rotor control, it is essential to disable it permanently.3. Disconnect the tail rotor pushrod at the tail rotor servo.4. Operate the tail rotor control at the transmitter; at about 2/3 of full travel in either direction the

servo should stop, even when the stick is moved further (travel limiting).5. Connect the tail rotor pushrod to the servo in such a way that the tail rotor’s mechanical end-

points in both directions are the same as the travel set by the travel limiter (servo should bejust short of stalling on its mechanical end-stop at this point).It is essential to make these adjustments mechanically, i.e. by altering the linkagepoints and pushrod length. Don’t try to do it electronically using the transmitter’sadjustment facilities!

6. Now correct the tail rotor setting for hovering, i.e. when the collective pitch stick is at centre,using the servo travel centre adjustment facility at the transmitter.

7. Gyro gain can now be adjusted between „0“ and maximum effect via the auxiliary channelonly, using a proportional control on the transmitter. If required, maximum gain can bereduced by adjusting the travel of the auxiliary channel or by adjusting the transmittercontrol. This gives you a useful range of fine adjustment for tailoring gyro response to yourrequirements.

8. If you find that the tail rotor control system is too responsive for your tastes, adjust it usingthe exponential control facility; on no account reduce servo travel, as it must be left at +/-100%!

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3. Pre-flight checksWhen you have completed the model, run through the final checks listed below before the firstflight:

• Study the manual again and ensure that all the steps of assembly have been carried outcorrectly.

• Check that all the screws in the ball-links and brackets are tightened fully after you haveadjusted gear meshing clearance.

• Can all the servos move freely, without mechanical obstruction at any point? Do they allrotate in the correct direction? Are the servo output arm retaining screws in place and tight?

• Check the direction of effect of the gyro system.

• Ensure that the transmitter and receiver batteries are fully charged. We recommend using avoltage monitor module (e.g. Order No. 3138) to check the state of the receiver battery onthe flying field.

Don’t attempt to start the motor and fly the helicopter until you have successfully checkedeverything as described above.Bear in mind that the running qualities of your motor will vary greatly according to the fuel inuse, the glowplug, the height of your flying site above sea level and atmospheric conditions.Please read the notes on motor set-up which you will find later in this manual.

4. MaintenanceHelicopters, whether large or small, place considerable demands on maintenance. Wheneveryou notice vibration in your model, take immediate steps to reduce or eliminate it. Rotatingparts, important screwed joints, control linkages and linkage junctions should be checked beforeevery flight. If repairs become necessary be sure to use original replacement parts exclusively.Never attempt to repair damaged rotor blades; replace them with new ones.

5. Installing the hexagon starter adaptorThe electric starter must be fitted with the hexagon starter adaptor and freewheel, Order No.1621 (available separately). Follow the instructions supplied with the adaptor.

To start the motor rotate the rotor head until the starter adaptor can be engaged vertically in thehexagon starter cone in the cooling fan. Please note the following points:

• • • • Do not switch on the electric starter until you are sure that the hexagon spigot on thestarter adaptor is engaged fully in the starter cone.

• • • • Switch off the starter before withdrawing it (i.e. after the motor has started).

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6. Adjustments during the first flight

6.1 Blade tracking"Blade tracking" refers to the height of the two rotor blades when they are spinning. Theadjustment procedure aims at fine-tuning the pitch of the main rotor blades to exactly the samevalue, so that the blades rotate at the same level.

Incorrectly set blade tracking, with the blades revolving at different heights, will causethe helicopter to vibrate badly in flight.

When you are adjusting blade tracking you are exactly in the "firing line" of the blades,so it is important to keep at least 5 metres away from the model in the interests of safety.

You can only check blade tracking if you are able to see clearly which blade is higher and whichis lower. The best method is to mark the blades with coloured tape as follows:

There are two alternative methods: figure "A" shows the use of different colours on the bladetips; fig. "B" shows the use of the same colour, but applied at different distances from the bladetip.

Procedure for adjusting blade tracking

1. Set the helicopter to the point where it is almost lifting off, then sight directly along the rotorplane.

2. If you can see that the rotor blades are running in the same plane, no adjustment is required;however, if one blade is running higher than the other, the settings must be corrected.

3. Locate the pushrods between the swashplate and the mixer levers (4618.51); the adjustmentis made at the ball-links on both ends of these pushrods: unscrew the links to raise theblade, screw them in to lower it.

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6.2 Adjusting the motor

Please be sure to read the operating instructions supplied with your motor before youstart this section.

The correct matching of collective pitch and throttle when the helicopter is hovering is of crucialimportance to the model’s flying characteristics and performance. For example, if the pitch ofthe main rotor blades is too high, the motor may not reach the rotational speed intended, andthis may cause you to think that the motor is not powerful enough for the job. The fact that themotor will overheat and thereby lose more power tends to reinforce that idea. For this reasonfirst set the hovering collective pitch value exactly as described earlier in these instructions, thenmatch the motor settings to that.Although most motors nowadays are supplied with the carburettor adjusted to approximately theright settings, final adjustment of the needle valves can only be made under practical testconditions. Most motors now feature twin-needle carburettors, and in this case the starting pointfor adjusting the idle / mid-range needle is to screw it in to the point where it just dips into theneedle valve on the opposite side when the carburettor is half-open.

Typical twin-needle carburettor

For your first attempt at starting the motor open the needle valve 1½ to 2 full turns from closed,connect the glowplug to the plug battery and start the motor by engaging the adaptor on theelectric starter in the teeth of the fan and switching the starter on.

Caution: when the motor starts withdraw the electric starter from the fan teethimmediately, otherwise you could damage the model.

When the motor is running, slowly increase throttle/collective pitch. If the fuel mixture is too"rich" and the model fails to lift off, close (screw in) the needle valve in small stages. In order toset the motor correctly for hovering you will need to adjust the idle needle, which also governsthe mid-range settings. Note that any adjustment you make here is also influenced by theneedle valve setting. Carefully close (screw in) the idle needle until the motor runs smoothly athover, without any tendency to stop through too rich a mixture. If motor speed is then too low,increase the hover throttle setting at the transmitter. Never attempt to increase the motor speedfor hovering by setting the idle needle too lean. The final needle valve setting can only be madewith the model flying under power with "full collective", and for this reason you are bound to startby "feeling your way" slowly to the correct setting.

If in any doubt, always set the mixture on the "rich" side. Initial hovering flights shouldalways be carried out with the motor set distinctly rich.

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7. General safety measures• Take out adequate third-party insurance cover.

• Wherever possible join the local model flying club.

7.1 At the flying site:• Never fly your model above spectators.

• Do not fly models close to buildings or vehicles.

• Avoid flying over agricultural workers in neighbouring fields.

• Do not fly your model in the vicinity of railway lines, major roads or overhead cables.

7.2 Pre-flight checks, flying safety:• Before you switch on the transmitter check carefully that no other model flyer is using the

same frequency.

• Carry out a range check with your RC system.

• Check that the transmitter and receiver battery are fully charged.

• Whenever the motor is running take particular care that no item of clothing can get caught onthe throttle stick.

• Do not let the model fly out of safe visual range.

• There should always be a safe reserve of fuel in the tank. Never keep flying until the fuelruns out.

7.3 Post-flight checks:• Clean oil residues and dirt from the model and check that all screws etc. are still tight.

• Look for wear and damage to the helicopter, and replace worn parts in good time.

• Ensure that the electronic components such as battery, receiver, gyro etc. are still securelyfixed. Remember that rubber bands deteriorate with age and may fail.

• Check the receiver aerial. Conductor fractures inside the flex are often not visible from theoutside.

• If the main rotor should touch the ground when spinning, replace the blades. Internal bladedamage may not be visible from the outside.

• Never carry the model by the tail boom: too firm a grip will easily deform the tail rotorpushrod.

8. A few basic terms used in model helicopter flyingThe term "rotary wing machine" indicates that the helicopter’s lift is derived from rotating "wings"which take the form of rotor blades. As a result, a helicopter does not require a minimumforward speed in order to fly, i.e. it can hover.

8.1 Cyclic pitchCyclic pitch variation is used to steer the machine around the roll and pitch axes. Changingcyclic pitch has the effect of altering blade pitch depending on its position in the circle. Theeffect is caused by tilting the swashplate, which then effectively tilts the helicopter in therequired direction.

8.2 Collective pitchCollective pitch provides control over vertical movement, i.e. for climb and descent. The pitch ofboth rotor blades is altered simultaneously.

8.3 Torque compensationThe spinning rotor produces a moment which tends to turn the whole helicopter in the oppositedirection. This effect must be accurately neutralised, and this is the task of the tail rotor. Tailrotor blade pitch is altered to vary torque compensation. The tail rotor is also used to control themodel around the vertical (yaw) axis.

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8.4 HoveringThis is the state in which the helicopter flies in a fixed position in the air, without moving in anydirection.

8.5 Ground effectThis occurs only when the machine is close to the ground, and it falls off as altitude rises. At analtitude of about 1 - 1.5 times the rotor diameter ground effect is completely absent. Normallythe revolving airflow from the main rotor is able to flow away freely, but in ground effect the airstrikes an obstacle (the ground) and forms an "air cushion". In ground effect a helicopter can liftmore weight, but its positional stability is reduced, with the result that it tends to "break away" inan unpredictable direction.

8.6 ClimbAny excess power above that required for hovering can be exploited to make the helicopterclimb. Note that a vertical climb requires more energy than an angled climb which includesforward motion. For this reason a model with a given amount of motor power will climb morerapidly at an angle than vertically.

8.7 Level flightA helicopter absorbs least power when flying straight and level at about half-power. If you havetrimmed the machine carefully for a steady hover, it will tend to turn to one side when flownforward. The reason for this phenomenon is that the rotor blade which is moving forwardencounters an increased airflow caused by the wind, and this increases its upthrust comparedwith the blade which is moving downwind, where the same airflow has to be subtracted. The netresult is a lateral inclination of the helicopter.

8.8 DescentIf the helicopter’s rotor speed is relatively low and you place the helicopter in a fast verticaldescent, the result can be that insufficient air flows through the rotor. This can cause what isknown as a "turbulent ring stage", when the airflow over the blade airfoil breaks away. Thehelicopter is then uncontrollable and will usually crash. A high-speed descent is therefore onlypossible if the helicopter is moving forward, or if the rotor is spinning at high speed. For thesame reason care should be exercised when turning the model helicopter downwind after flyinginto wind.

8.9 Flapping motion of the rotor bladesAs we have already seen, the forward-moving blade produces greater upthrust than the otherblade. This effect can be minimised by allowing the forward-moving blade to rise and the otherblade to fall. The rotor head is fitted with what is known as a flapping hinge to allow thismovement, and this prevents the rotor plane tilting excessively in forward flight. In modelhelicopters a single hinge shared by both blades has proved a good solution to the problem.

8.10 Auto-rotationThis term refers to a helicopter flying without motor power. The rotational speed of the mainrotor can be kept high by setting both blades to negative pitch, and the airflow through the rotoras it descends then keeps the blades turning. The rotational energy stored in the rotor by thismeans can be converted into upthrust when the helicopter is close to the ground, by the pilotapplying positive collective pitch. Of course, this can only be done once, and it has to be done atthe correct moment. Auto-rotation allows a model helicopter to land safely when the motor fails,just like a full-size machine.

However, auto-rotation places considerable demands on the pilot’s judgement and reflexes; youcan only halt the machine’s descent once, and you must not "flare" too early or too late. Muchpractice is required to get it right.

Order No. 4458

GRAUPNER GmbH & Co. KG D-73230 KIRCHHEIM/TECK GERMANY

AGUSTAA109 POWER

ReplacementpartsDate of issue: 6/04

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2

Nose undercarriage

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GraupnerOrder No.

PartNo.

Description Dimensions[mm]

No. OffReqd./Pack

in 4458.3 A1A2A3A4A5A6

L.H. nose fore-and-aft bulkheadR.H. nose fore-and-aft bulkheadCross-pieceCross-pieceStrutPivot plate

112121

4616.16 F23 Arm section 2

4616.17 F20F9

Yoke sectionDowel pin 2x29

21

4616.18 F19 M2 threaded sleeve 3x20,5 2

4616.19 F40 Wheel, 2-part 1/1

4616.20A F22F30

SpringBuffer

12

4616.21 F24F3

LeverActuating pin 2x20

2/11/1

4616.22 F25 Large bush 14/8x6 2

4616.23 F27 Small bush 10/3x5,5 2

4616.24 F26 ColletGrubscrew

14/8x5M3x3

2/14/2

4616.25 F29 Aluminium tube 6/4x40 mm 1

in 4616.28 F28 Shaft 3x65 mm 1

98.325 F31 Threaded rod M2x35 1

4618.55 Ball-linkLinkage ball

2/102/10

704.8 Cheesehead screw M2x8 2/20

704.10 Cheesehead screw M2x10 2/20

564.4 F41 Brass tube 3,2/4x10 1/1m

710 Nut M2 3/20

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Main undercarriage

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GraupnerOrder No.

PartNo.

Description Dimensions[mm]

No. OffReqd./Pack

4458.41 F1 Main undercarriage retract unit 2

in 4458.4 F2 Main undercarriage leg 2

in 4458.4 F5 Collet 2

in 4458.4 F4 Reducer sleeve for undercarriage leg 2

4616.19 F40 Wheel, 2-part 2/1

4618.55 Ball-linkLinkage ball

2/102/10

107 Grubscrew M3x3 2/10

from 704.20 F6 Cheesehead screw M2x20 2/20

704.8 Cheesehead screw M2x8 2/20

710 Nut M2 2/20

in 4458.3 A7A8A9A10

Servo console side panelServo console frameTail rotor bulkheadSupport bulkhead

2431

(Some parts not illustrated)GraupnerOrder No.

PartNo.

Description Dimensions[mm]

No. OffReqd./Pack

4458.1 B1 GRP fuselage, white 1

4458.2 B2B3B4

Upper fuselage fairing, GRPTail cap, GRPSpoiler, ABS

111

4458.3A1A2A3A4A5A6A7A8A9A10A11A12A13A14A15A16A17A18A19A20

Set of wooden parts, consisting of:Nose fore-and-aft former, L.H.Nose fore-and-aft former, R.H.Cross-pieceCross-pieceStrutPivot plateServo console side panelServo plateTail rotor bulkheadTail rotor shaft support bulkheadFront mechanics supportRear mechanics supportSpacerUpper mechanics support plate, L.H/R.H.Top joiner lugHorizontal stabiliser rib, smallHorizontal stabiliser rib, largeIn-fill stripBottom joiner lugCross-strut support

112121423111201 each222412

4458.4 Retractable undercarriage, complete 1

4458.9 Window set with dummy exhausts andvent grills, clear smoked tint

1

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GraupnerOrder No.

PartNo.

Description Dimensions[mm]

No. OffReqd./Pack

4617.3C1C2C3C4

Set of plastic parts, consisting of:L.H. horizontal stabiliser panelR.H. horizontal stabiliser panelInstrument panelDummy rotary light

2212

4618.54 B6B7

Channeled rail, balsaCross-strut, balsa

10X1010X10

11

4618.64 B9 Tail rotor drive shaft 2mm 1

1291.21 B5 Bracket (upper mechanics attachment) 2

3500.3 B8 Plastic guide tube 3,2/2,2x1000 2

4447.16 B10 Carbon fibre tube 5Ø, 850 lg 1

1291.10 B11 Pushrod 2,5Ø x 75 lg 2

519.3,0 B12 Tailskid, piano wire 3Ø x 300 1/1m

1004.2,0 B13 Retaining wire 2,0Ø x 250 2/1m

4618.155 M2.5 ball-link 2/10

from4618.55

Linkage ball 2/10

704.8 Cheesehead screw M2x8 2/20

710 Nut M2 2/20

747.7 Self-tapping screw 2,2x6,5 40/20

747.10 Self-tapping screw 2,2x9,5 6/20

746.16 Self-tapping screw 2,9x16 4/20

565.16 Socket-head cap screw M3x16 2/20

aus 4618.71 Socket-head cap screw M3x25 4/1

4458.200 Building instructions (German)

4458.203 Building instructions (English/French)

Accessories4448.103 Hexagon starter cone 1

1621 Hexagon starter adaptor with freewheel 1

2239A Stainless steel exhaust manifold rear exh. 1

2238A Stainless steel exhaust manifold side exh. 1

2240 Stainless steel tuned pipe silencer 1

2258 Stainless steel universal compact silencer 1

2253 Stainless steel compact silencer 1

4458.99 Decal sheet (blue/gold) 1