8/11/2019 Bulldog. Hlg. Article&Plan. Model Builder September 1980 (1)

1/3

/,,-

1116"

t16"

HARDWOOD

TRtp

WING

=

SOFT

BALSA 114'x

4-117'

x 2O"

STABfLfzER= SOFTBALSA 1116'l l 'x9"

/

RUDDER=

/\

/

soFr

BALSA

\

-/

,l''",'-')'-

/ l ' t I t l

. / t l

=r--.=

*----

SUB-RUDDER=

.

SOFT

/16"BALSA

POLYHEDRAL ETAIL

FUSELAGE

HARD

BA SA

/4'x2-114'x22"

l-o*oWt* nott

THE

BULLDOG"

8/11/2019 Bulldog. Hlg. Article&Plan. Model Builder September 1980 (1)

2/3

:BULLDOG:

Bv

WILLIAM

LANGENBERG

. . An

all-out

competition

HLG, alcit

larger

han

m.ost,

or experienced

6,iir.i;r*r"J'rt-il;;r. tt's he 23rd(andbest) n a series f HLG'sdesignedv theauthor.

.

In

recent

years

he

Popular

model

masazines

ave featured

a

substant ia l

nui.rber

of so-called

beginners"

pro-

iects.

efore

roceedingu ther

w th h s

;r t icle,

feel t should

e

made

lear hat

BULLDOC

does

not

fit into

this

cate-

eorv.

On the

conlrdrY

BULLDOC

s a

Eand-launched

l ider

designed

or the

exoerienced modeler with a better-

than-average

hrowing

arm.

Ihis model is the

lwenlv-third

n a

series

f

or ig inal

and-launched

l iders

which

have

bui l tover

he

past

ecade.

It waschristened

BULLDOC

because

ts

abilities

o

stay

ogether

on the

most

powerful

launih

and

to soar

on

the

i l iehtesthermal

ef lecled

he enacious

qualities

of

its

namesake.

BULLDOC's

predecessorsan he

Samul

n respecl o

5i7e,

proport ions,

weiShl ' and

lorce

arrangemenls.

hrough he

experience

eaine-d rom

these

models,

he

basic

design

n

these

pages

radually volved.

BtiLLDoc

is somewhat

arger

than

the average

outdoor

hand-launched

slider,

yel"

t

is not

so bully

that

th e

"modeler

with a

good

throwing

arm

cannotdchieve

mpressive

eight n

the

launch.

n addi t ion,

he

relat ively

arge

sizeand

low wing

loading

enable

his

model o

floaton

uocu

rents

o

which

ts

smal ler

competi tors

do

not

normal ly

resoond.And orobablymost mportant'

the

arge

ize

bnds

o keep

he

model

n

sieht

6nger

after

t catches

lhermal.

- the

fuselag"

prot i le of

BULLDoc

orovides

a

relatively

arge,

ow

trontal

area.This

ends

to

lower

the

center

of

gravitv

and

makes

he

rudder

area

es s

:ri t ic;1.

A

oolvhedral,

undercambered

wine

with

fair lv

shal low

polyhedraI

aneEs

s used

n

coniunct ion

wi lh th is

fusilaee design. Such a combination

orovid-es

excillent

lateral

and

longi-

iudinal

stabi l i tv.

BULLDOC

s a

stable

flier

n both

caim

and

windy

conditions,

with

nei ther

the

lateral

rocking

nor

susceptibility

o spins

prevalent

n many

hand-launched

l iders.

So

much

for ihe

history

and

design

theorv behind

this

model

l believe

t is

suff icient

o

say

hatwhen

properly

ui l t

and

f lown,

EULLDOC

wil l

Present

a

threat at

anY

contest.

CONSTRUCTION

These

nstructions

will be

brief

since

the

reader sassumedo be amiliarwith

hand-launched

l iders.n

general , . t ry

o

use

lhe desiSnaled

Erades.ol

balsa

n

order

o keep

down

the

wergnt

bear

n

mind that

hi

oerformance

f

the

glider

will be

in direct

proportion o

the care

used

n

its construction.

RUDDER

AND

STABILIZER

Select

some

5-6

lb. semi-quarter

srained 1/16 sheet balsa or the tail

iurfaces. Cut

them

to

their

required

out l ines.

The rudder

is sanded

to a

streamline

shape.

Sand

the stabilizer

into the

airfoii

section

shown

on

th e

Continued

on

Page

96

8/11/2019 Bulldog. Hlg. Article&Plan. Model Builder September 1980 (1)

3/3

ftaa ${nTs

ME AND

MY RC

't

coLoR

rxclusrvE

rGHrs

FnoM

noYAL

CFOWN O A|

Your

choice

PLAIE

BOA' caF on poly

ester/ cotlon T-shin

Af A VINGS

AtrAwlnet

,"."r.4""c,o9f

1

^,^,

6.

SO

Si:. S, M, L, XL + soa

Pollror

Wa do cuslom wotk for

cluba.

lFitl .vant , businclroa

Intonndion

3anl

on

raquagl.

fta

a sHnTs

1132 fl,

RtY

.

t^t

vtcAs,

NtvAoA

(,02187 1624

8'|OI

blockaresimulatedwith black nk,asare

the

control surface

outlines.

The ail skid

smadeout

of two

pieces

ol basswood.

Fil l in the bottom

of the

fuselaqeat the aft end

between

the

lower' iongerons

ith a small

r iangleof

balsa

o support he

tail skid,

The nsignia

oes

n thelopofthetop

wings, n

the bottomof

the ower

wings,

and-onboth sides

of the

rudder,

n

the

locations hown.As ar as can ell here

were

no

other

markings on the

real

airDlane.

Thermals orever Even

ndoors.

.

Butfdog

. , , ,

Continued

from

page

59

pran.

WING

The wing is the

main elementof

the

CUSIO,,

TUNEO

ENC//[ES

CON'fTfircN

ACCESSOA'ES

Cor, OS l.t,

noatt a

Sttr..

fte..

EDttna.

soacLlrt,.

ln

clt,om

f.o- oat/oal

at.t

...at .nola...

fh.o,,t.cl f.o.'t ara{.D|..

Comctaaa

6ianao.,

ol

t,oca a cu.,otr

D.taa.

tl.td-,o.gaa Lama asct .. clt o6 na..tt

r.lrat,

,aclnt .h..1.,

QU|t

lt

a,

ttt.,

.ttsl.olat,

a

6.., o,t...,

Er..tattlre lo. e/C t co.a.ot

,lrt.

..ctre

,teo.Ar

AAA , t t .e.cl.r:

ooo.tr... .Ora X aO' ..,t.t

ltn.. t2 aC

Pttt.

Fo. .t.a.tl.d b.ocrt

r., ..n.t 25

c.aa, ,c:

t.a,on X.at,.at...lrlD aot

2cat L.?tra

tl a

c. t l . t2a5t

' ] t :

(7|a)

a'o-sraz

model and reouires he most etfort to

build. Start

work by choosinga

sheetof

5-6 lb. semi-quarter

grain

balsa

1/4 x

4-1/2

x 20 nches ong. Cut the

wint to

the

proper

outl ine

and then

glue

the

1/16 x 3/16 spruce

strip to the

leading

edge.

When this

is

dry,

taper he

wing

blank from a 1/4-inch hickness i

the

center to 1,/16

nch at each tip.

Nexl,

sand

he

proper

undercamber

nto the

lower surface. hen carveand sand he

wing into the linal desired

irloilshape.

Finally,cement

in the required

poly-

hedral angles sshown

on the

plan.

fUSELAGE

Usea oiece

oI 15 b.6alsa'l/4

x2-1/4\

22 inches

ong for the

fuselage.

Carve

and sand

it to shape using the cross-

sections

hown on

the

Dlan.

f desired,

the

Iuselagemaybe built up using

3/16

x 3/4 inch piece of spruce or the tail

boom splicedor

laminated

nto

a

for-

ward section

of balsa.

ASSEMBTY

Clue the stabil izer

n

place,

olloweo

by

the rudder and

sub-rudder.When

thesearedry atiach

he wing,ensurinta

good

fit

between

uselage nd under-

cambered

section.

nstall he throwing

patch

and

checkalignment

hrouthout.

Double coat all glue joints for added

strength.

BUlLDoc should balance

t the C.C

point

on the

plan.

I have ong

favored

permanent

ballastover

modeling clay,

sincebalancing laycan

produce

up to

three

imes he coefficient f drag

as he

norma fuselage cross-5ection.

Per-

manentballast

; the orm of

lead

canoe

inserted n the

noseand smoothed ver

with

glue

or

plastic

wood, thus

per-

mitting

a smooth

uselage ontour o be

maintained.

fINISHING

Two coats of thin nitrate dope should

be

sulficient for the empennage

and

fuselage. recommend the following

procedure

for the wing. Rub talcum

powder

into the

pores

of

the wood and

wipe off any excess. Seal the powder

with

one

coatofthin

nitratedope.Then

sand the

wing smooth. Complete

the

linishing

process

y applying

wo

more

coatsof

nitratedope and hen

polishing

the winr

with

automobile

wax. Be

sure

to

add v-our

AMA license umber o tne

upper

ight

wing

as

shown n the

photo-

traPns.

TlYING

BULLDOC should

weigh about

1. 2

oz. complete.

Before attemptint test

fl ights, remove any

warps which may

have appeared

n the flying surfaces.

Then adiust model for lelt circles of

about

ifiy feet in diameter.

Because f

its size and

polyhedral

arrangement,

BULLDOC ansa{elv

andlea consider-

able

amount of rudder.

or best esults,

the slider should be launchedat a 45o

angle to the

r i tht. When

pro pe

y

adiusted and thrown. it should

make

about

three-ouarters f a turn

to the

right before

eveling

ff

into

a

eft

glide.

Alter directionof launchuntilthe

model

pul ls

out on top,

headingnto he

wind.

Practice aunchins he BULLDOG ntil

you

are

confideni the

model wil l

pull

out

into

the

wind under

varyingweather

conditions.

Under

present

ontest onditions,

he

hand-launched

lider

event

inevitably

involvesan

element of luck.

I firmly

believe,however, hat

you

can become

more consistently

ucky

by developing

vour abi l i tv

to f ind and

launch into

ihermals. n this

regard,do not hesitate

to

piggyback

otf a competitor circling

overhead in a thermal. You can be

certainyour competitorswill piggyback

off

you

if they can

Workbench.

,

Continued

from

page

6

traded that two-wheeler

n

for

a

four-

wheeler.

INDUSTRY

NEWS

Just

eceived

word from

Joe

Bridithat

Bridi Hobby Enterprises

as

purchased

Pro Line

Electronics,nc., lock, stock,