Crane Fly Lite

Crane Fly Lite A Tom Wright Design Rev 1.1a

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Crane Fly Lite

A Tom Wright Design

Crane Fly Lite

Crane Fly Lite A Tom Wright Design Rev 1.1a

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Contents

Introduction ................................................................................................................................................... 3

Acknowledgements ....................................................................................................................................... 3

Parts List ........................................................................................................................................................ 4

Specification .................................................................................................................................................. 5

Fuselage Construction ................................................................................................................................... 6

Tail Support ................................................................................................................................................... 7

Rudder Control Arm ...................................................................................................................................... 8

Rudder ........................................................................................................................................................... 8

Fin .................................................................................................................................................................. 8

Tail-Plane ...................................................................................................................................................... 9

Elevator ......................................................................................................................................................... 9

Mast Top ...................................................................................................................................................... 10

Fitting the Mast............................................................................................................................................ 10

Roll Control Arm ......................................................................................................................................... 11

Variant 1 .................................................................................................................................................. 11

Variant 2 .................................................................................................................................................. 12

Delta Plate ................................................................................................................................................... 13

Undercarriage .............................................................................................................................................. 14

Tailskid ........................................................................................................................................................ 14

Servo Mounting ........................................................................................................................................... 15

Rudder and Elevator Servo ...................................................................................................................... 15

Roll Control Installation and Servo ......................................................................................................... 15

Rotor Blade Construction ............................................................................................................................ 16

Blade Root Re-enforcement .................................................................................................................... 17

Blade Balancing ........................................................................................................................................... 18

Blade Covering ............................................................................................................................................ 18

Rotor Blade Installation ............................................................................................................................... 18

Initial Setup ................................................................................................................................................. 19

Trimming and pre-maiden checks ............................................................................................................... 19

First Flight ................................................................................................................................................... 20

Drawings...................................................................................................................................................... 22

Balsa Parts (6mm) ................................................................................................................................... 22

Balsa Parts (3mm) ................................................................................................................................... 23

Glass Fibre Parts ...................................................................................................................................... 24

Piano Wire Parts ...................................................................................................................................... 25

Crane Fly Lite Introduction

Crane Fly Lite A Tom Wright Design Rev 1.1a

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Introduction

Thank you for taking time to download the Crane Fly Lite Autogyro build details, but be warned this

fascinating offshoot of our hobby can be very addictive and often challenging, as applying certain aspects of

fixed wing intuition may sometimes not produce the desired results. Over the years many have dabbled and

given up on Autogyros because the machines were too demanding to fly without experiencing frequent

mishaps resulting in long repair sessions, and uncertainty about what went wrong.

The Crane Fly Lite is designed specifically to maximise the chances of early and on-going success, if the

model is built to plan, flown, and trimmed in accordance with the suggestions within this document. A single

rotor Autogyro will probably never be a suitable project for a novice pilot but this design endeavours to

make success feasible for “A” standard pilots onwards, and is equally suitable for very experienced pilots

wishing to get started with what is often referred to as the “dark art”.

The Crane Fly Lite is an attempt to lift the dark veil and is the result of many hundreds of hours work in

collaboration with experts in various associated fields who have given their time and energy freely to enable

me to complete the project and make it available to all model enthusiasts.

The design is subject to copyright so any recipient intending to use it for commercial gain must contact me in

writing beforehand.

Constructors are asked to kindly post on the modelflying.co.uk or rcgroups.com autogyro forums, whenever

possible, photos, videos, or text as the build progresses, and of course the outcome in terms of flight success.

But most importantly do ask questions particularly if you are new to Autogyros.

Good Rotations.

Tom.

Acknowledgements

The Crane Fly Lite concept was developed after many hours flying conventionally configured Autogyros and

during this time taking note of the control characteristics that presented the greatest challenge to pilots flying

single rotor machines for the first time.

During the development process other enthusiasts, some with professional qualifications in related

disciplines, took interest and began to provide input to the project, so it would be remiss of me not to extend

a thanks in recognition of the many hours work freely given to enable the project to become available to all

wanting to get started with an Autogyro project for the first time, or indeed for RC pilots who may have not

succeeded first time around.

My thanks and appreciation goes to:

Giovanna My Partner

Malcolm Hancock For applying his Technical drawing and three dimensional CAD skills;

mechanical engineering advice and test flying the clone prototype.

“Mickey” Nowell For help and advice, in respect to aerodynamics and rotary physics.

Dave Mellor For volunteering as a novice pilot flight assessor and providing great

encouragement throughout the project.

All the RCM&E forum guys who have provided feedback from PDF previews.

The Lads at the field Including Pete, Fred, Stuart, Richard, Mark, Richard and Peter for input after

flying the model.

Stuart Eggerton HD video and flight assessments.

And last but not least;

Rich Harris For originally inspiring my interest in Autogyros.

Crane Fly Lite Parts List

Crane Fly Lite A Tom Wright Design Rev 1.1a

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Parts List

Part Description Quantity Used on Web

Link

Balsa 3mm x 75mm x 900mm 1 Med Sheet All Tail/Fin Parts

Balsa 6mm x 75mm x 900mm 1 Soft Sheet Fuselage Cabin

Balsa 5mm x 75mm x 900mm 1 Hard Sheet Rotor blades

Balsa 5mm x 19mm x 900mm 2 Trailing

Edge

Rotor blades

Balsa 6mm x 6mm x 200mm Triangular

Section

Tail/Fin Support

Spruce 6.5mm x 12.5mm x

920mm

1 Strip Boom/Mast/Roll

Control Arm

G10/FR4 Glass Fibre

Sheet

0.4mm (1/64") 300mm x

150mm

Various Coolwind

G10/FR4 Glass Fibre

Sheet

0.8mm (1/32") 110mm x

110mm

Delta Plate Coolwind

CNC cut GF Parts and

Delta plate

All GF Parts +

Delta Plate

Coolwind

Servo 3.7g mini man 2 Elevator/Rudder Giant

Shark

Servo Tower Pro MG90 1 Roll Control Giant

Shark

Motor Emax BL1812 (1800kV

140W)

1 Giant

Shark

Prop DD7040 GWS Style EP

Prop 7x4

1 Giant

Shark

ESC 20A or higher with BEC 1 Giant

Shark

2mm Gold Connector

pairs

3 pairs Motor/ESC

Connection

LiPo Battery 1000mAh 3S 20C 1 Giant

Shark

Receiver 3 or more

Channels

1

Blue Wonder Motor

Mount

1 Rotor Bearing

Holder

Giant

Shark

Flange Bearing 3x8x4 - (F693zz) 2 Rotor Bearing Coolwind

Servo Extension Lead 500mm Ultra Light Type 2 min length 350mm Giant

Shark

Y-Lead 100mm 1 short as possible Giant

Shark

Piano Wire 18 SWG - (1.2mm) 3 lengths Blades, Rudder Arm, Tail Skid,

Elevator/Rudder

Piano Wire 12 SWG - (2.5mm) 1 length Undercarriage

Push Rod 2mm 85mm long Roll control

Crane Fly Lite Parts List

Crane Fly Lite A Tom Wright Design Rev 1.1a

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Part Description Quantity Used on Web Link

Control Horn Small 1 Elevator

Plastic Ball Link 2mm 1 Roll Control

Tape - Coloured 48mm Blade Covering &

Decoration

Giant Shark

Tape - Fibre 25mm Elevator/Rudder Hinge

Hook & Loop Tape 25mm 150mm Battery, ESC, RX fixing

Pushrod Connector 1.5mm 2 Elevator & Rudder

Pushrod Connector 2mm 1 Roll Control

M3x8mm Hexagonal Spacer 1 Rotor Spindle (Variant 2) Spiratronics

M3x 12mm dia Washer 10 Various, Rotor washers Coolwind

M2.5x8 + Locknuts &

Washers

3 Rotor (BW Motor) mount Coolwind

M3x16 + Locknuts 3 Rotors

M3x25 + Locknut 1 Roll Arm

M3x35 + Locknut + Plain nut 1 Rotor Spindle

M2x20-25 mm+ 2 plain

nuts+Washers

1 Ball Link fixing

Flange Head Self Tapping

No 4x12mm long

Not Servo Screws 3 Undercarriage Coolwind

Motor Screws 3 Motor

60mm Wheels Lite Wheels 2 Giant Shark

Wheel Collets Plastic tube or

Collets

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Specification

The Crane Fly Lite is a 3 bladed Rotor Autogyro, with direct control of Roll on the rotor head, and pitch and

yaw control with conventional elevator and rudder surfaces. The Roll and Rudder controls are fully coupled

through a Y-Lead to a single channel on the receiver.

Blade Length 432 mm 17 inches

Overall Length 790 mm 31.1 inches

Weight no Battery 370g 13 ounces

inc 1000mAh 3S Battery 450g 16 ounces

Inc 1300mAh 3S Battery 510g 18 ounces

Crane Fly Lite Fuselage Construction

Crane Fly Lite A Tom Wright Design Rev 1.1a

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Fuselage Construction

The Crane Fly Lite Fuselage is constructed from 6mm balsa sheet mounted on a Spruce boom and re-

enforced with Glass fibre sheet for the Motor mount, undercarriage mount and tail-plane assembly.

The boom is made from a single piece of 6.5 x 12.5mm Spruce strip, 700mm

long.

Prepare the Spruce strip by drilling a 1.5mm hole in the narrow face at an angle

of 45 degrees and 10mm in from the end in readiness for fitting the tail-skid at a

later stage of construction.

The fuselage floor is made from 6mm balsa 330mm x 50mm with the last 50mm

of the floor tapered down to the boom width.

Glue the Spruce Boom onto the balsa fuselage floor ensuring that the tail-skid

hole is at the back and on the bottom and that the spruce boom is centred on the

balsa floor.

Cut and prepare the 6mm fuselage sides and formers as detailed in the drawings.

Test fit the fuselage parts to the

floor/boom assembly. The fuselage sides

have built-in motor down-thrust and mast

tilt angles of 5 degrees, so it will be

necessary to trim the bottom of the

firewall, bottom of the rear former and

the inside of the boom slots to ensure

they sit at the required 5 degree angle.

When satisfied with the fit, cyno the

fuselage parts in place

Trim the front edge of the fuselage floor so it is flush

with the firewall.

Pre-drill the holes in the fibreglass firewall to fit your

chosen motor, with the motor centre at 18mm from the

top edge.

The motor mounting holes should be sized to match the

self-tapping screws which will attached the motor

A 5mm clearance hole for the motor shaft, and a similar

sized hole for the motor wiring are also required.

Glue the fibreglass firewall in place.

Crane Fly Lite Fuselage Construction

Crane Fly Lite A Tom Wright Design Rev 1.1a

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On the underside of the fuselage

add the Undercarriage Mount,

Cable exit plate and a 25mm wide

piece of Velcro for holding the

battery in place.

Note that the holes in the

undercarriage mount are pilot

holes for the self-tapping

undercarriage screws.

Cut away the balsa inside the

cable exit plate

On the inside of the fuselage add two small GF re-

enforcement plates for the front two undercarrirage

screws to bite into, strengthening the undercarriage

mounting.

Tail Support

Finally add the 40 x 50mm GF tail plane support plate and its two supporting 50mm long balsa 6mm triangle

section pieces. Glue these securely in place.

The Fuselage assembly can now be put to one side whilst the tail-plane components are constructed

Crane Fly Lite Tail Construction

Crane Fly Lite A Tom Wright Design Rev 1.1a

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Rudder Control Arm

The Rudder control arm is constructed from a 90mm

length of 1.2mm diameter piano wire. The two

angled sections each being 20mm long and the

centre section is 50mm long.

The wire can easily be bent by using pliers.

Ensure the bent arms are at 90 degrees to each other

On the lower 20mm section glue the three glass fibre

parts and attach a small (1.5mm) control rod clamp.

Rudder

The Rudder is constructed from medium hardness 3mm balsa, 124x32mm with a decorative rounded top

corner and an angled cut-off at the base to allow for elevator movement.

The rudder is hinged with a tape hinge on its left-

hand side. The edge of the rudder which will

mate with the fin needs to be sanded to a 35

degree angle to allow Rudder movement.

On the right-hand side of the Rudder at the bottom, carve a slot to

accept the previously bent control arm. The horizontal section of

the cut out should be 23mm from the lowest edge of the Rudder.

Cyno the control arm in place and then re-enforce the side with a

glass fibre plate.

Fin

The fin is constructed from a single piece of medium hardness 3mm balsa,

132x69mm, with a leading edge slope designed to minimize the chances of blade

strikes during heavy arrivals.

Shape the Fin as shown on the template/drawing page and attach the Rudder to it

using a piece of 25mm wide fibre tape as a hinge.

Crane Fly Lite Tail Construction

Crane Fly Lite A Tom Wright Design Rev 1.1a

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Tail-Plane

The tail-plane is constructed from a single

piece of 3mm medium hardness balsa, 276

x 50mm. The outer edges are aesthetically

shaped as per the drawing/template.

Elevator

The Elevator is constructed from a single piece of 3mm medium hardness balsa, 304x50 mm with the outer

edges aesthetically shaped to match the tail-plane. The leading edge has an underside chamfer to allow

downwards movement. It has a centrally located cut-out for the Rudder controls to pass through and features

a centre brace and two thin strengthening ribs to resist splitting along the grain.

The drawings show only one elevator half, due (to paper size

restrictions), and needs to be mirrored on the centre edge to

produce a full size template.

Once the balsa has been cut and shaped, as shown on the

template, then the underside leading edge of the elevator needs

to be chamfered to 35 degrees. This is simply sanded to shape

with a sanding block.

On the underside of the elevator glue the GF elevator brace centrally and add two 4mm wide GF rib strips.

Now attach the Elevator to the tail-plane using two pieces of 25mm wide re-enforced fibre tape, remember to

leave a gap of about 20mm in the centre for attaching the fin assembly.

Glue the Fin assembly to the Elevator, taking care that it

is vertical and in line with the centre line of the tail-

plane. The fin is supported on either side with 50mm

lengths of 6mm triangle section balsa

Attach the Elevator control horn securely to the elevator

strengthening plate with glue or screws; ensure it is on

the opposite side to the Rudder control arm.

Fit a 1.5mm Control rod clamp in a hole on the horn

about 15mm below the glass fibre plate.

Finally glue

the completed

Tail-plane

assembly to

the fuselage

assembly.

Take care to ensure the tail-plane assembly is aligned square to the fuselage and boom.

Crane Fly Lite Mast and Rotor Control Arm Construction

Crane Fly Lite A Tom Wright Design Rev 1.1a

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Mast Top

The mast is constructed from a straight length of 6.5 x 12.5mm spruce - 148mm in length.

The first task is to clad the top of the mast in GF sheeting.

Use the mast as a gude to mark out the width of the GF parts.

These are then cut with scissors and glued in place with cyno

Three sides at the top of the mast need to be clad in GF

as shown in the picture

Then a 3mm hole is drilled 6mm from the top in the

centre of the narrow face.

Care needs to be taken to ensure that the hole is drilled

square to the mast as this forms the pivot point for the

Autogyro’s roll control. The use of a pillar drill is

highly recommended for this task.

Fitting the Mast

The mast is required to tilt 5 degrees backwards when fitted to the model. This angle is built-into the

fuselage box construction, however, the base of the mast needs to be trimmed so that it sits neatly on the

boom.

Shape the bottom of the mast

by removing 1mm from the

back edge. This will create

the required 5 degree angle.

The completed Mast can then

be glued to the rear former

and boom and then re-

enforced with the two

fibreglass plates shown on

the drawings/template pages.

These also have the 5 degree

angle built-in to them.

Glue the Servo mounting

plate to the mast 55mm from

the top.

Crane Fly Lite Mast and Rotor Control Arm Construction

Crane Fly Lite A Tom Wright Design Rev 1.1a

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Roll Control Arm

The Rotor Control Arm is offered in two different variants, both are functionally identical but offer the

builder a choice of construction methods dependant on the parts or tools they have available.

The Control arm is mounted on the mast with an M3x25mm screw with large washers on both sides and an

M3 locknut.

Variant 1

This variant uses an M3x30mm socket head cap screw as the rotor pivot.

An M3 die may be required to extend the threaded section by 2mm.

Construction

The Rotor control arm is constructed from a 50mm length of 6.5x12.5 spruce.

First drill the fixing hole for a 2mm ball link connector. This is a 2mm hole in the

narrow face of the spruce, located 5mm in from the end.

Clad the opposite end of the spruce in GF sheet in a similar fashion to

the mast top. Ensure you use the same thickness GF as on the mast.

Four pieces of GF are required; two 12.5mm square and two 6.5mm x

25mm. These are easily cut-out with scissors

Now drill a 3mm hole through the control arm at the centre of the

12.5mm square GF cladding. Again this needs to be square, so use a

pillar drill to ensure accuracy.

Finally cut and glue the side plates over the clad control arm. The two

holes in the side plates need to be aligned accurately. This can be

achieved by temporarily bolting them to the mast top with an M3

screw whilst the glue on the control arm sets.

The rotor bolt (M3x30mm) is inserted from the underside of the arm.

Note that unthreaded shank of the bolt will protrude through the top

surface of the control arm.

M3x12mm washers are used as packing to cover the unthreaded shank

and allow a plain nut to tighten down on the control arm face, locking

the rotor bolt in place.

The exposed threaded shaft needs to be long enough to fully accept

the Rotor bearing, its housing and a locknut (see assembly in next

section). If this is not the case, due to tolerances on your parts, then

the threaded section of the screw will need to be extended to allow

satisfactory assembly. An M3 die will be required to do this. If you

have used a hardened M3 screw then the dies generally available on

the hobby market may not be strong enough to cut the extra thread and variant 2 of the design should be

considered.

Crane Fly Lite Mast and Rotor Control Arm Construction

Crane Fly Lite A Tom Wright Design Rev 1.1a

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Variant 2

This variant uses an M3x30mm socket head cap screw which screws into an M3x8mm

hexagonal spacer glued into the spruce arm. The rotor bearings run on the unthreaded

part of the screw.

Construction

The Rotor control arm is constructed from a 50mm length of 6.5x12.5 spruce.

First drill the fixing hole for a 2mm ball link connector. This is a 2mm hole in the

narrow face of the spruce, located 5mm in from the end.

Then drill a 5.5mm hole for the hexagonal spacer.

The spacer should be a tight fit in the hole, generally 5.5mm

is fine for the metric spacers; for other types measure the

maximum distance across the spacer and use the next

smaller drill size. The length of the spacer is not critical, but

it should not protrude greater than 3mm from the underside

of the control rod, to allow adequate clearance from the

mast when assembled.

Tap the spacer through the hole, apply some medium cyno and tap it back in the hole until the top of the

spacer is level with the top of the control arm.

Now drill a 3mm hole in a 12.5mm square piece of GF and glue it

over the top of spacer to provide additional resistance to pull

through of the spacer under load.

Next add a similar size GF piece on the underside with a hole in it

to clear the protruding spacer.

Add the two side GF spacer plates, and the two GF Control arm

pivot side plates. The two holes in the side plates need to be

aligned accurately. This can be achieved by temporarily bolting

them to the mast top with an M3 screw whilst the glue on the

control arm sets.

The completed control arm assembly

Crane Fly Lite Delta Plate Construction

Crane Fly Lite A Tom Wright Design Rev 1.1a

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Delta Plate

The Delta plate is a triangular plate made from 0.8mm glass fibre sheet with each side 102 mm (4 inches)

long. The plate MUST be made from 0.8mm glass fibre sheet – other materials or thicknesses will not be

suitable and will severely affect the models flight characteristics.

0.8mm GF sheet can be cut with multiple cuts with a strong modelling

knife or with a hand saw. Note that GF sheet will blunt blades and saws

quite quickly.

Use the drawing/template to accurately mark out the plate. The 3mm blade

mounting holes are located 30mm from the centre of the plate.

Initially drill the centre hole at 3mm diameter.

Assemble a couple of flanged bearings in the top and bottom of the Blue

Wonder motor mount and temporarily attach the mount to the plate with a

3mm bolt.

Align the mount holes with the rotor blade holes.

Using the mount as a guide, drill the first 2.5mm fixing hole, then put a

bolt through this hole to stop the mount moving whilst the remaining two

2.5mm holes are drilled

Enlarge the centre hole using a drill or file until it clears the diameter of

the flanged bearing (approx. 10 mm), i.e. the flange of the bearing will

easily drop through the enlarged hole.

Assemble the Delta plate by attaching the Blue Wonder motor mount

using three M2.5x8mm socket head cap screws, washers and three M2.5

locknuts. Then insert the three bearings. A flanged bearing is inserted

from the top and one from the bottom, a non-flanged bearing may

optionally be placed in the middle if you desire, although it is not strictly

necessary.

DO NOT use the small grub screw supplied with the motor mount to hold

the bearings in place as it will almost certainly distort the bearings.

Variant 1 Assembly Variant 2 assembly

Crane Fly Lite Undercarriage Construction

Crane Fly Lite A Tom Wright Design Rev 1.1a

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Undercarriage

The undercarriage is constructed from a 480mm length of 2.5mm diameter (12SWG) piano wire which is

bent to shape using a hammer and vice. It is attached to the model on the undercarriage mount by three

Flange headed steel self-tapping screws. No 4x12mm. The undercarriage is held in place by its built-in

spring tension against the three screws.

The undercarriage is designed to take reasonable impact during a landing and to spring off in the event of a

heavy arrival. It is not designed for ROG as the model is normally hand launched.

Construction

Take the 480mm length of piano wire and make a tight bend at the

centre to form a Vee shape. You are aiming for an angle of around 30

degrees.

Then place the Vee into a vice, holding about 40mm in the vice. Bend

the protruding legs forward and outward with a hammer or other tools,

until the forward rake of the legs is around 15-20 degrees and the gait

is around 300mm. These are not critical dimensions, but the

undercarriage needs to be wide to prevent tip-over when the model

lands.

Finally bend the ends outwards to form the two axles about 20mm

long. These should be in-line with each other. Final adjustments to the

stance of the undercarriage should then be made until it is similar to

the drawings provided.

Add the Wheels, secured with wheel collets or short sections of plastic

tube held in place with cyno.

The undercarriage is attached to the model using No4 A2 Stainless steel

flanged self-tapping Screws.

Please note that these are NOT servo screws, which are very soft and

unsuitable. If sourcing them, or an equivalent, proves difficult then M3

screws with a washer and nut may be substituted.

Tailskid

The tailskid is made from a short length of 1.2mm piano

wire.

Using a pair of pliers, make a small loop at one end of the

wire, then glue the Tailskid into the hole at the rear of the

boom.

Crane Fly Lite Servo Mounting

Crane Fly Lite A Tom Wright Design Rev 1.1a

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Servo Mounting

All the servos on the model are fixed to the model using medium cyno.

Firstly, remove any labels from the servo side faces where cyno will be used. Roughen up the plastic surface

with abrasive paper, apply a small amount of medium cyno and hold the servo in place until the cyno cures.

Curing will take longer than the time the manufacturer states for the curing time as there is little or no

moisture in the faces being mated to kick off the curing process. Be patient.

Rudder and Elevator Servo

The Rudder and elevator are controlled by two small 3.7g

servos. These are glued either side of the boom, at the rear,

25mm from the leading edge of the tail-plane assembly.

The servos are connected to the Rudder

and elevator by 1.2mm diameter piano-

wire rods, with Z-bends at the servo and

small rod clamps on the control surfaces

Note that the Elevator is set for 2-4mm

down trim at neutral

Roll Control Installation and Servo

The Roll control arm is first attached to the mast using an M3x25mm Hex Cap screw and locknut, with large

washers under the screw head and locknut.

Do not over tighten the locknut, the roll

control arm should be free to move without

binding, but tight enough to minimise any slop

in the arm.

An MG90 metal gear servo, or similar, is then

glued to the GF plate on the mast.

A 2mm ball link and an 85 mm long x2mm

push rod, then connects the servo to the

control arm. Ensure the ball link is secure but

free to move.

The Control Arm should be set at 90 degrees

to the Mast with the servo in its neutral

position.

Crane Fly Lite Rotor Blade Installation

Crane Fly Lite A Tom Wright Design Rev 1.1a

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The Crane Fly Lite Rotor blades are 432 mm (17 inches) long with a 45mm chord and shaped to an Aquila

section. They are a simple and easy construction of balsa weighted on the leading edge with piano wire and

re-enforced at the root with glass fibre sheeting. A small amount of negative incidence to aid spin up is

provided by a piece of 0.4mm shim material.

Although three blades are required it is recommended that you make a spare one using balsa from the same

sheet.

The target weight for each blade is under 25 grams with the FG fitted and the blade covered; with all four

blades being of equal weight. Careful selection of the wood blanks will make achieving this easier and

reduce the need for adding additional weight during the balancing process.

Rotor Blade Construction

Take a hard balsa strip 432 x 25 x 5mm and cut a 1.2 x 1.2 mm rebate down the length of the strip.

Constructing a “cutter” using the following method will help you achieve good consistent results on all

blades.

Cyno together a scrap of 0.4mm GF and a scrap

of 0.8mm GF and then Cyno a Number 10A

scalpel blade on top with its point protruding

over the edge by about 1.2mm. Don’t worry if

it’s slightly more as the cyno used in the next

stage will seal the overcut.

Holding the Balsa blade flat on the bench, run

the cutter along one edge, then stand the balsa

blade vertically. Hold it securely and run the

cutter at 90 degrees to the previous cut.

Remove the square fillet of balsa.

This should produce a nice clean rebate into which the 1.2mm piano wire nicely fits.

If it does not, then use the end of the piano wire put a radius on the on the rebate by

scraping the wire down the rebate.

Glue the piano wire in the rebate using medium thickness cyno, holding the piano

wire in place with masking tape until the cyno has cured.

Now cyno the trailing edge section in place, ensuring that the blade

is perfectly flat and that the faces match perfectly. The edge of the

trailing edge section will need a light sanding to make it vertical.

Taking a sharp modelling knife, scalpel or David plane, remove a

5mm wedge from the leading edge using the piano wire as a

convenient straight edge.

Crane Fly Lite Rotor Blade Installation

Crane Fly Lite A Tom Wright Design Rev 1.1a

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Then using a long sanding block sand the rotor to give the section shown in the photo below.

Note that the trailing edge is thinned down to

1mm and that the maximum thickness is 5mm

at about 25% chord.

Shaping the blades is NOT a difficult task. Start by reducing the trailing edge thickness to 1mm, by holding

the sanding block flat against the top surface of the Trailing edge section taking the same amount of wood

off the whole width of it. Then round off the leading edge and gently blend the top surface to give the desired

section.

Blade Root Re-enforcement

Remember that the blades turn anti-clockwise, so with the blades

pointing away from you and the leading edge on the left-hand side

then the blade root is closest to you.

On the top of the blade, at the root, draw a line at the one third chord

position from the leading edge. Use this line to position and glue the

topside GF re-enforcement centrally over the line.

Now attach the underside GF re-enforcement, so that the square edge

of the re-enforcement is towards the leading edge as shown in the

picture below.

Trim the trailing edge to shape

(approx. 50 mm off cut) and drill the

3mm fixing hole as vertical as

possible through the blade from the

top surface. (Use a pillar drill if

available).

Shims

Finally add the small 0.4mm GF

shim piece on the underside 4mm

from the hole centre towards the

trailing edge.

This completes the rotor Blade Construction.

Crane Fly Lite Rotor Blade Installation

Crane Fly Lite A Tom Wright Design Rev 1.1a

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Blade Balancing

The final task is to balance the blades. The closer in weight and

balance the better, as this reduces vibration when the blades are

spinning.

Chord-wise Balance

Checking and adjusting the blade balance chord-wise is not

necessary on such light blades with a wire leading edge. The weight

of the piano wire leading edge pretty much guarantees it will be in a

good position.

Length-wise Balance

Using a sensitive digital weigh-scale (resolution of 0.1g or better), weigh all the blades accurately. On each

blade write its weight (in pencil) on the GF.

Tape a round pencil or a 300mm length of 6mm dowel to your bench. You will use this to lay the blades

across it like a child’s See-Saw to find the length-wise balance positions.

Lay the heaviest blade on the See-Saw and find the point where it balances.

Lay another blade next to it, and adjust its balance point by adding weight (tape or PVA glue) close

to the Root or Tip until it balances at the same point (or with 2mm) as the heavy blade.

Repeat this process for all blades using your original heavy blade as a reference.

Weigh all the blades again, and write their weights on the GF. (rub out the old pencil mark)

The (new) heaviest blade becomes your reference blade.

Add weight (tape) to the lighter blades at their balance points to bring them up to the same weight as

your reference blade.

You should now have a complete set of blades all with the same weights and the same balance points.

Blade Covering

The blades can now be covered, sealing in the balance

weights, using a lightweight coloured self-adhesive tape and

fibre tape on the leading edge.

Note the sequence of applying the covering. This ensures that

the edges of the tape are not exposed to the oncoming wind.

Rotor Blade Installation

The Rotor blades can now be installed on the Model. Double

check that you have added the 0.4mm shims towards the rear

edge of the blades.

The Rotors are attached using M3x 16mm Hex Cap screws

with large 10-12mm diameter M3 washers all secured with

M3 Locknuts.

The tightening of the bolts needs to be done carefully, as the rotors need to be free enough to be able to move

in spin-up and find their own positions using centrifugal force, but tight enough so that they do not move

when the model is held up at an angle during initial spin-up.

Crane Fly Lite Flight Notes

Crane Fly Lite A Tom Wright Design Rev 1.1a

19

Initial Setup

Elevator neutral position should be set to give 2-4mm of down trim, and the roll control head should be

vertical.

The picture above provides all the basic control movements for your first familiarization flights. These can

be adjusted to your taste as you become more comfortable or proficient in flying the Model.

Note that the Rudder and Roll control are “hard” coupled using a Y-Lead to the primary turn control on your

transmitter, for both Mode 1 and Mode 2 flyers this is normally the right-hand stick.

The use of Expo or dual rates is not required during your familiarization flights, if the Model is setup as

described.

Trimming and pre-maiden checks

When the model is completed do take time to check….

The boom is true; any slight deviation can be corrected by rudder trim equivalent to the

error angle.

Check the tail is square to the boom and the fin lines up with the boom centre line.

Ensure the mast is vertical, as a small error will affect the direction and amount of rotor

roll trim required.

The fire wall is square to the boom centre line, any deviation will require motor thrust

offset to correct.

Do not guess the motor power that is available. Check with a watt meter and with a

fully charged 1A or 1.3A lipo. Power checks with the prop fitted should be done

outdoors, observing all the usual safety procedures. The absolute max indicated power

must not exceed 160 Watts; but 120 Watts is adequate for a maiden flight.

If everything so far checks out remove the prop, power up the Rx and Tx and adjust the rotor roll trim until

the rotor bolt is vertical.

It is important to note that any reference to roll trim, left or right is always viewed from the rear. The elevator

trim should be set at 2-4 mm down and adjusted as required after the first trim check flight.

Crane Fly Lite Flight Notes

Crane Fly Lite A Tom Wright Design Rev 1.1a

20

Next ensure the rotor spins freely and the retaining nut is secure, use thread lock if necessary. If the delta

plate has been made accurately and the simple blade balancing procedure has been carried out, the rotors

should spin up readily after a hand start and a walk forward with the model held back at least 45 degrees.

If any vibration is present, or spin up is not smooth and progressive then you could have the rotors bolted

down too tightly, if this is the case there could be insufficient force to overcome the bolt tension which will

not allow the blades to find their natural position after reaching operating speed. A little practice getting the

blade bolt tensions reasonably equal and yet sufficient to hold the blades in place during the hand start and

run up to speed will ensure the most efficient vibration free performance.

Practice walking forward with the model held well back, and ensuring the blades are a safe distance from

your head! Get used to the sound and feel of the rotor reaching operating speed or as its better known

autorotation. If a swishing sound cannot be heard then attempting a launch will result in a quick turn to the

left into the deck. If everything checks out fine read though the next section that covers the suggested

procedure for the first flight attempt.

First Flight

When the model is built and set up to plan, and everything is carefully checked, the last thing to do is rush to

the field and attempt a full power launch. At this point it’s worth saying that this model is only intended for

hand launching and is designed to be flown with the rudder coupled with roll. By far the best way of

achieving success is to look at the possibility of getting a properly experienced Auto gyro pilot to help out

with the maiden and monitor your first few solo attempts. There are also regular Auto gyro events crammed

with knowledgeable and experienced pilots who will be willing to help out.

When arriving at the field check the wind conditions and aim for a light breeze 2-5 mph, should give easy

spin up for hand launch. Next check the position of the sun relative to the into wind heading, this is

important as glare from the side or directly in front of the operating area will make disorientation far more

likely. If the wind is direction is steady try and identify a distant object as an into wind reference point, or if

the wind is light and variable check every time before each flight. It all sounds like simple common sense but

it's surprising how often things get forgotten in the heat of the moment.

Next consider the safety of onlookers or club mates, I have seen a first attempt resulting in a 180 degree turn

back towards the pilot and onlookers so consider all the possibilities and select a safe area. If a helper is hand

launching for you make sure they have had time to familiarize themselves with the feel of the model and the

sound of the rotors at auto rotation, also make absolutely sure that the model is held well clear of the helpers

head, and away from others.

Give the rotors a turn by hand and hold the model well up with the rotors angled at 45 degrees, or more, to

the oncoming wind, Identifying the sound when the rotors are up to speed is very important, if you are not

sure never attempt a launch. Rotors will normally make a swishing sound as they reach speed and you should

be able to feel an upward pull equal to the models weight.

If the model has been set up and trimmed correctly the first real flight should mainly involve gentle roll

inputs and manipulation of throttle and elevator, but the first thing to establish is the amount of power

required to get away, and the amount of forward push needed. If the model is held vertically and power

progressively applied you will feel the model getting lighter note the throttle position as a guide to the launch

power setting. As for the amount of "bung" energy required this should not be excessive or too feeble, lighter

models are capable of rising from your hand into a breeze with an appropriate power setting but for first

attempts a firm “bung” with the rotors up to speed and at a slightly nose up attitude should do the trick.

This is where the fun starts as some quick assessments need to be made with measured control inputs applied

to keep things in order. If the model is climbing straight ahead at a fairly high power setting then it will soon

get to a distance were the first turn will be too fast and too far away, so as soon as a safety height of 30-50 ft

is reached start by progressively reducing throttle, and lowering the nose to the point where the model is

maintaining height and travelling at a nice steady speed equivalent to a slow cruise, unless you are a very

confident pilot, at this stage, trimming via the Tx will cause an unwanted distraction, so if the model is still

fast hold a little up in and re adjust power, and if possible land straight ahead by reducing power

progressively and using the elevator to flare as terra firma approaches. Should the landing be less than

perfect then give the model a good check over before a further attempt is made.

Crane Fly Lite Flight Notes

Crane Fly Lite A Tom Wright Design Rev 1.1a

21

It is likely that the first attempt will involve some use of roll and pitch trim correction; if this is applied to

coarsely while the model is tearing about at speed then you will be lucky to recover the model. These early

sorties should be all about establishing a steady low cruise speed, and establishing if trim adjustments are

needed to avoid holding in roll or pitch on sticks. When correct trim settings have been established don't

expect to be flying hands off while chatting to mates, full concentration and focus will be needed throughout

all early flights to avoid disorientation.

If you find the model climbing out ok but pulling left or right, hold on the sticks, then progressively reduce

the power and land. A model out of trim in roll, or pitch is very difficult to fly particularly for a first Auto

gyro flight.

Excessive speed and distance away from the pilot are the first major factors that determine success or failure,

add in glare, and distraction, to set up the ideal conditions for unrepeatable utterances, and a damaged model.

Good sun glasses and a distraction free environment are as important as controlling speed.

Many pilots prefer a left hand circuit direction, if this is you, then start by only making turns to the left and

trimming the model for a gentle left turn; this idea should greatly help with orientation as the model should

always be turning left. Just a slight nudge on the stick should produce a bank, if the control input is too

course the bank angle should be restricted by short applications of opposite stick but be careful not to over

control or let the nose drop. Very gentle turns can be achieved without use of elevator but initiating a bank

and then neutralizing the stick while applying back stick and a touch more power should get you around ok.

If you are finding the first minute in the air stressful reduce power progressively and land to take stock of

what may be needed for a more relaxed flight.

This may to some seem hard work but believe me when I say; flying these machines can be very easy indeed

it's just a matter of developing an instinctive feel, and a little practice. Most pilots find that maintaining

orientation is a problem during early flights and later if over confidence creeps in.

Keeping the model reasonably close in, at a steady speed, helps with control and orientation, as does the old

method of standing side on to the direction of flight.

Maintaining focus on one part of the model also seems to help, I tend to follow the tail but a well-defined

part of the decor can also be used is a focal point. Many employ bright contrasting colours, but the

effectiveness does depend on the light conditions, and the viewing angle between the pilot and model.

205

50

85°

85°

4.4

Fuselage Base

2 Reguired

HALF SCALE

51x37mm

Fusalage Side

Firewall

Rear Former

A4

SHEET 1 OF 4

6mm (1/4")Balsa PartsSCALE:1:1

37

6.50

Cable ExitCutout addedduringconstruction

50

50

6.50

330

38 18

4

5

51

3mm BalsaFin

3mm BalsaTail-Plane

ElevatorOnly half shownElevator is built inone piecePlease Mirrorthis drawing

Rudder

See Construction notesfor details of carvedRudder Control Arm slot

32

124

13

BB

Elevator304 x 50 mm

50

69

77°

132

10

50

276

SECTION B-B

SHEET 2 OF 4

3mm (1/8")Balsa Parts

R30

Mast Side

Rotor Blade Upper

Rotor Blade ShimRotor Blade Lower

Rotor Blade Parts

Firewall

2 of each requiredControl Arm Components

PlateRudder Control Arm

Rudder Components

Rudder

2 off requiredMast Support

2 off

Mast Components

2required

SHEET 3 OF 4

Glass Fibre Parts A4

SCALE:1:1

3

10

12

25 30

38

72°

30

5

MastServo Mount

35

35

12.50

25

6.50

47.90

4

3

25

12.5 25

6.50

30

6.50

Delta Plate MUST beDelta Plate MUST beDelta Plate MUST beDelta Plate MUST bemade from 0.8mm (1/32")made from 0.8mm (1/32")made from 0.8mm (1/32")made from 0.8mm (1/32")

Glass Fibre SheetGlass Fibre SheetGlass Fibre SheetGlass Fibre Sheet

102

50

56.5

18

2

Elevator Brace & Rib

12

68

43°

27

30

15

Mast Top

40

50

85°

TailplaneSupport

50

40

Undercarriage Mount

18

48

60

40 12.5

Leg length 175 mmAxle length 20 mmTotal Wire length 480 mm

Piano Wire diameter 2.5 mm

Tailskid, Elevator & Ruddercontrol rods - all 1.2mm

Shown Full size

Wire PartsSHEET 4 OF 4

Side View1/2 Scale

20 degreeraked forward

1/2 Scale3D View

Undercarriage

Front View1/2 Scale

320

Top View bend DetailActual Size