Laurel outlook., 1946-05-01
Fleets Action
In Battle Tried
Tests Made in Water Basin
To Show How Warship
Would Act in Fight.

PHILADELPHIA.-When a NAM
moth battleship or carrier in the
Pacific vas a target for Japanese
bombs or wallowed in hurricane
seas, the captain and his crew would
know exactly how the ship would
perform because Of a relatively
tiny 8-foot model that sailed months
before in an indoor basin of water.
Similarly, the first LCIs and LISTS
were sent on vital, but hazardous
assignments halfway across the
world because the designers of the
new type craft, previously INFESTED
in warfare, were certain of their sta
bility and operation.
Model ship building used to be
little more than an intriguing hobby,
but the technique has been greatly
extended in recent years, according
to Henry E. Bossell, president of
the Cramp Shipbuilding company,
and it reached a new high during
the war.
Behind the 10, 000-ton cruiser that
slides off the ways at a shipyard,
he explained, is a'series of scale
models showing how the craft can
be Unanswered under any condition,
how much strain the structural
parts can withstand, where the
shell plates are to be placed, where
the machinery will be fixed and the
boats and cargo stored.
Safety Assured.
Veterans returning home recent
ly have been carried by transports,
for instance, that braved 100-foot
waves with safety. There was a
minimum of concern aboard, since
the ship in miniature had come safe
ly through equally rough seas in a
small tank during its first stage of
designing. Even the force of an I'M
derwater explosion can be tested in
this manner.
These unitarian models are sell
dom seen by the general public, but
they are the forerunner of the intri-
cate exhibition models, which often
cost $4,000 to SIS, 900. They also
found a new purpose during the high
production war period in teaching
apprentice ship builders all the de-
tails of their industry.
The first models are of simple
construction, often a rough draft
carved out of wood to give not the
appearance but the shape of the yes
sci, Mr. Rossell said. Usually they
measure 16 to 20 feet in length, but
sometimes the miniature is only 4
or 5 feet long, scaled at one-eighth
or one-sixteenth of an inch per
foot.
Tested in tanks or basins, the
models are used to predict the
speed resistance, turning character
istics, roll and pitch and strength of
structural parts under a load of the
finished ship. They must be lowed
through the water, which has mech
anism to produce any type of sea,
or they may be equipped with small
horsepower motors and propellers.
Measure for Steel.
Other rough models show the
placement of shell plates, enabling
the manufacturer to estimate exact
ly how much steel should be ordered
before the ship is under construc-
ton. Hollow models of brass or plas-
tic permit the designer to place min
lature machinery inside the hull,
conflicts and %overcrowd-
arrange the bridge and steer
ing gear or test the cargo appara-
tuS.
In Philadelphia examples of this
latter type are now on exhibition at
the Franklin institute in a navy dis
play of the LIST "Queen of the In
yasion." Built for the navy by a
New York firm of naval architects,
hey were the starting point for the
INVASION craft production.
"A large steel model reproduces ev-
cry piece of machinery, apparatus,
'ivet, bolt and screw in the LIST.
Another wooden model, accurately
and operated by a push-but-
on, demonstrates the lowering of
he door and ramp with tanks and
rucks ready to drive onto the beach
Included in this technical class of
hip models at a shipyard, Capt.
Garland Fulton, chief of engineer
ng at Cramps, pointed out, is the
'ne-half to one-quarter size wood
md paper dummy called a 'mock-
Ip." Not a thing of beauty, he x
'lained, it is used by workmen to
tudy sections of the ship and work
ut details such as piping, ventila-