advanced scale models DeHavilland DH88 Comet User manual

Brand: advanced scale models

Model: DeHavilland DH88 Comet

Type: User manual

Advanced Scale Models DeHavilland DH88 Comet is a semi scale ARF R/C model of the famous winner of the 1934 MacRobertson, England to Australia Air Race. With an 88-inch wingspan and a length of 59 inches, this model is perfect for experienced RC pilots. It can be powered by two .32~.40 2 stroke engines, two .52 4 stroke engines, or two brushless electric motors. The model requires a 5 or 6 channel radio and additional items such as servos, glue, and covering materials. It features retractable landing gear, flaps, and ailerons, making it a realistic and fun-to-fly model.

DeHavilland

DH88 Comet

INSTRUCTION MANUAL

A semi scale ARF R/C

model of the famous

winner of the 1934

MacRobertson, England

to Australia Air Race.

Wingspan: 88 inches (2235 mm)

Length: 59 inches (1500 mm)

Engine/

2 x .32~.40 2 stroke

Motor:

2 x .52 4 stroke

2 x brushless electric motors

Radio: 5 or 6 channel

DeHavilland

DH88 Comet

Histor

y of the DeHavilland DH88 Comet

The original DeHavilland DH 88 ‘Comet’ was specially designed to compete in the 1934 England to Australia

MacRobertson Air Race. Three were designed, built and tested in eight months with the first flying on the 8th

September 1934.

The all wood aircraft was powered by two special DH Gypsy Six R engines producing 230 h.p each. The

Comet was the first British air

craft with r

etractable landing gear

, flaps and contr

ollable pr

opellers.

Sponsor

ed by Australian MacPherson Robertson, the MacRobertson Air Race was the longest ever Air Race

from Mildenhall in England to Melbourne, Australia with the winner receiving 10,000 English pounds.

Piloted by Charles Scott and Tom Black, the winning aircraft GACSS (named Grosvenor House after its

sponsor

, a luxury hotel in London) won the race in 70 hours and 54 minutes.

Wingspan - 44ft (13.41m)

• Wing Ar

ea - 212sq.ft. (16.69m

) • Length - 29ft (8.84m) • Height - 10ft (3.05m)

• Empty Weight - 2,840lb (1,288kg) • Max Takeoff Weight - 5,320lb (2,413kg) • Fuel Capacity - 258 gal

• Engines - 2 x 230 h.p. DH Gypsy R • Cruising Speed - 220mph (354km/h)

• Maximum Speed - 237mph (381km/h) • Service Ceiling 19,000ft (5,790m) • Range 2,925 miles (4,707km)

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Page 1

_____

Safety Warning:

This R/C aircraft is not a toy. Serious injury or damage to property can result through misuse and abuse. It

is recommended that this aircraft is flown at a dedicated R/C flying site and that a qualified instructor

thoroughly checks over the model before its first flight.

Your local model shop should be able to assist you r

egarding flying clubs in your area.

Additional Items Required to Complete the DH88 Comet:

• 2 x Metal geared micro servos for aileron control

•

3 x Standard size high torque servos for rudder, elevator and flap control

•

1 x Additional micro servo required if optional retractable landing gear is fitted

•

2 x Additional standard size servos required for glow engine power (throttles)

• 2 x Suitable ESCs for electric power version

• 5 and 30 Minute epoxy glue

• Medium and thin CA adhesive

• Masking tape

•

2 x .32~.40 2 stroke engines & 10 x 6” to 11 x 7” props or

2 x .52 4 stroke engines & 10.5 x 8” to 12.5 x 6” props

(for i.c. version)

•

2 x 36-30-2/1500 RP/V motors & 8” x 5” props or

2 x 36-30-3/1000 RP/V motors & 10” x 5”~6” props

(for electric version)

_____

Page 2

_____

STEP 1:

Trial fit the tailplane to the fuselage and mark where

the area of covering will need to be removed to

expose the wood and enable the glue to adhere

roperly. Carefully cut through the film covering

inside the marks - ensuring that you do not cut into

the wood sheeting.

STEP 2:

Make a groove in the tailplane for the

pre-assembled elevator joiner/control

horn to rest.

STEP 3:

Using a sharp knife or a

round file, make a small

notch in the fuselage to

clear the elevator joiner

and the rudder/tailwheel

assembly

STEP 4:

Connect the elevator

pushrod to the elevator

joiner/contr

ol hor

n and

fit into position in the

fuselage.

STEP 5:

Connect the rudder/tailwheel pull/pull

cables to the assembly then slide the

tailplane in position. Before gluing the

tailplane in position, make sure that is

corr

ectly aligned in relation to the wing.

STEP 6:

Now run a small bead of

medium CA ar

ound the

outside tailplane/fuselage

joint. This will prevent glue

running onto the tailplane

covering when applying

medium CA adhesive to the

inner joint.

_____

Page 3

_____

STEP 7:

Using 5 minute epoxy, secure the vertical fin in

position making sure that it is square in relation to

the tailplane. After the epoxy has set, run a bead of

edium CA around the outer joint.

STEP 8:

Using the supplied hinges, fit

the elevators and rudder in

place by applying a few

drops of thin CA adhesive to

both side of the hinge.

STEP 10:

Then fit the ailer

on servos to the

removable hatches with some

double side foam tape. For

extra security we would suggest

fitting additional hardwood

mounting blocks.

STEP 11:

Measure and mark the half way

point of the alloy wing joiner

tube.

Glue the alloy tube into one of

the wing panels. Only insert

tube up the half way point.

Let epoxy set thoroughly before moving to the next step.

STEP 9:

Feed aileron extension leads though the centre

wing panel. A hole approximately 16cm from the

leading edge will have to made in the center section

for the leads to exit.

_____

Page 4

_____

STEP 12:

Before glueing the outer

wing panel to the centre

section, apply masking tape

round the edges of the

panels to be joined to help

prevent glue running on to

the covering. Join the panels with 30 minute epoxy. Remove the

masking tape from the panels before the epoxy has set. Use

rubbing alcohol or methylated spirits to remove any epoxy residue.

STEP 13:

Secure the ailerons in place

with a few drops of thin CA

adhesive applied to both

sides of the hinges.

Fit the control horns to the

ailerons and assemble the pushrods from the supplied parts.

STEP 15:

The DH88 Comet is designed to

use either glow or electric power.

The supplied engine mounts ar

used for both glow and electric

power

STEP 16:

Fitting Glow Engines.

For glow engine power the

e-assembled thr

ottle servo

mounts need to be installed alongside the fuel tanks in each of the

engine nacelles.

STEP 14:

Install the elevator and

rudder servos in the

plywood servo tray in the

fuselage.

Adjust the length of the

elevator pushrod and the rudder pull/pull cables and fit to the

appropriate servo.

Elevator

Servo

Rudder

Servo

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Page 5

_____

STEP 17:

Installing Electric Flight Batteries

he installation of electric flight

batteries will vary depending on the

battery type and size used.

The suggested mounting position

(for Li-Poly batteries) is under each

motor using Velcro straps. We recommend that hardwood rails be installed

in this area for added strength and security.

STEP 18:

The nacelles can now be fitted to the

centre section using the Allen headed

bolts supplied. You may wish to

apply a bead of silicon sealer to the

inside edge of the nacelle and, after

protecting the wing with tape, wipe

off any excess silicon as the nacelles

are bolted up to protect the wing surface from the nacelles rubbing.

STEP 19:

Fixed Landing Gear

Position the pre-assembled fixed

landing gear assembly in the slotted

hard wood mounting rails in the

engine nacelles.

Secur

e with the supplied landing

gear straps and scr

ews.

STEP 20:

Optional Retracting Landing Gear

The retractable gear units use the same mounting rails as the fixed

landing gear

Route the airlines so they exit through

the same hole as the servo leads.

The air tank, r

etract servo and valve

can all be neatly mounted on the wing

centre section. Secure with the

supplied landing gear straps and

scr

ews.

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Page 6

_____

STEP 22:

The receiver and receiver battery are

mounted on the pre-installed

plywood tray at the front of the

fuselage.

Secure the hatch with four of the

supplied small self tapping screws.

STEP 21:

The flaps are supplied pre-hinged and simply require a

suitable servo installing in the pre-cut well and a linkage

making. As the hinge line is not straight, we recommend

hat ball links are used. Check that the flaps operate

freely. They are suprisingly effective and offer a

reasonable braking effect during landing appproaches.

STEP 23:

Fit the tail wheel fairing using some

medium CA adhesive.

STEP 24:

Fit the engine nacelle fairings to the

wing using medium CA adhesive.

STEP 25:

Fit the clear nose cone and canopy

in position with the small screws

ovided.

STEP 26 - Balancing the Model:

As with all air

craft it is imperative that the model balances at the

correct Centre of Gravity. The C.G. for the Comet is 115mm from

the leading edge measured at the fuselage side.

Note: if the optional retractable landing gear is fitted, balance the

model with the landing gear retracted.

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Page 7

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Guarantee

Advanced Scale Models guarantees this kit to be free from defects in both material and workmanship at the

date of purchase. This does not cover any component/parts damaged by use, misuse or modification. In no

case shall Advanced Scale Models’ liability exceed the original cost of the kit.

In that Advanced Scale Models has no control over the final assembly or the material used for final

assembly, no liability shall be assumed for any damage r

esulting from the use by the user of the final

user-assembled product. By the act of using the final user-assembled product, the user accepts all resulting

liability.

Distributed in the USA

by:

Global Hobby

18480 Bandilier Circle,

Fountain V

alley

CA 92708. USA.

Distributed in Eur

ope

by:

Ripmax Ltd.,

241 Green Street, Enfield,

EN3 7SJ. UK.

Distributed in Australia

by:

Model Engines (Aust.) Pty. Ltd.

Unit 1, 158-168 Browns Road,

Noble Park, VIC., 3174

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Page 8

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Flying Tips:

•

Retractable Landing Gear:

ecause the landing gear retracts rearwards there will be a change in the

aircraft’s trim. While the change in trim is small, it is noticeable and the pilot should be aware of this

characteristic.

• Use of Flaps: With the flaps lowered the Comet will ‘balloon’ upwards slightly and will require some down

elevator trim. It is recommended that when flaps are deployed for the first time, do this at a safe altitude

and re-trim accordingly.

• Torque Effect: Being a twin engined aircraft, and with no direct prop wash acting on the rudder, the torque

of the engines/motors has a greater effect during the initial part of the take off. The aircraft will veer left

and the pilot needs to be ready to correct this with right rudder input. The amount of rudder needed for

correction will decrease as speed increases.

• Landing: Do not attempt to slow the model drastically on landing. It is recommended that ‘wheel’ landings

be performed rather than ‘three point’ landings.

STEP 27 - Setting the Control Throws:

Aileron - 10 mm up/down

Elevator - 25 mm up/down

Rudder - 30 mm left/right

Flap - up to 40 degrees.

advanced scale models DeHavilland DH88 Comet User manual

Brand: advanced scale models

Model: DeHavilland DH88 Comet

Type: User manual

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advanced scale models DeHavilland DH88 Comet User manual

advanced scale models DeHavilland DH88 Comet User manual

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