The sun. [volume] (New York [N.Y.]) 1833-1916, 1903-08-02
TRIPLE SCREWS F0R WARSgrps
ahner Engineer MeNiIie's GplnIcn Of That.
Practical yaIup

| 10 THE EDITOR OF The SUN-a Sw, Ia r,,.-
euitorlat OF july 30 concerning The vo,.".
oi inc hcarsarGe reference is mad, 10 ~.
| endurance speed trial of the cruiser G. olur,tts
winch occurred in The summer of Iso, n.,.,
that vessel crossed the Atlantic AT an avor,,'
speed ot il Il knots using natural draf, onIv
In ms editorial 1t is stated The Col,,,,,
Is one OF our two triplc-screw cruisers ,,Jt,a
chiet engineer at the end of her tcs, said U.s.
nc thought she would have done better Mad Nv,
ohru propeller been removed entirely T,,o
experiment of triple screws is accented o..
failure now II would be a value tLorar,r,
to test on a long voyage the speed o, A cr,,,,.
having the standard system Of propj,si,,
twin screws"
The use Of triple screws is highly fayorol L.,
inc onclals OF the German, Russian unI
french Admlralties In fact, II has hnAr oea
cially stated that Germany Will not here,f,o.
use any but triple screws in the hattlasb,,,
OF the home squadron The number of ,r,,T,
screw battleshps now in commission IL ~,
least treble those that were in existence who,
the Columbia made her successful run fro,,
southampton to New York.
A few DAYS after the Columbia reached Xsr
York the chief engineer of the vessel pers,n.
ally called my attention TO the statement tha,
had been attributed TO him as 10 the adyant,s.
In
third screw He told me that he had hoo,
instructed. since ne meant to say that bv
reason of the bunker construction. which
made it impossible TO secure sufficient coal 10
use forced draft. the third engine could not i'm
used az efficiently as the design provided for
Since the run Of the Columbia the question:
OF Installing triple screws has been very clr".
navies. Both in the French and German
navies triple screws were originally installed
for structural and economic reasons FL.
perience with these vessels has demonstrates
that tactical advantages can be secured from
such an installation since the man puvriny
qualities OF the ship are greatly improved where
discovered that the art Of steering can be &C.
CURED much more readily by the seamen
where there IL such an arrangement Of power
Is it not fact that the Cunard Stearnshrp
Company have practically settled upon TRIPS
screw design of motive power for the new
greyhounds which they are contracting foro
day the transatlantic steamer to be fitted with
turbine engines installation of motive
power where there may be not only three but
seem that the logical development of marine
machinery installation is in the direction NJ
more than two screws.
The latest British armored cruisers have an
installation Of 10000 horse power OF machIn.
cry. and 1t will only require the breaking Of
one OF the propeller shafts Of such an instal IA
such power should be transmitted through two
or through three shafts.
The installation Of three screws will also
materially redSce the excessive vibration NJ
machinery which is so obnoxious to ocean
going passengers. and which will seriously
increase the wear and tear of the hull strIC-
ture Those who have crossed the Atlantic
on an ocean liner fitted witbh triple screws
have noticed the improved comfort resulting
from the decreased vibration Of such machin.
cry over that of vessels where the power ia
transmitted through two shafts.
The trlDle-SCrew design liz the logical mr.
rangement of machinery Of cruisers. battle-
ships and ocean liners where there is nm ex-
cess Of 20 900 horsepower Of machinery IL
will not only be found that there are econom-
ical, structural and tactical reasons for such
an installation. but experience will show that
the life of the ship will be longer 1t is simply
engineering retrogression TO fail to Use trlpls
screws IN very large, powered vessels. and tins
opinion Is sustained by the experience and
judgment Of those officials OF naval and mer.
camille services which are in possession OF
such ships. GEO. w. MELVILLE.
Engineer-in-Ch Z. S Navy.
WASHINGTON, July 80