The daily morning journal and courier. [volume] (New Haven, Conn.) 1894-1907, 1900-11-13
TRIALS OF THE VIPER.
Statement From Her Inventor, the
Hon. Charles A. Parsons.

i Hon. Charles A. Parsons.
Sir: The recent trials of II. M. S.
Viper, which is the first torpedo boat
destroyer to be fitted with steam tur-
bine propelling machinery, have at
tracted much attention, and as the re-
suits, which have been published from
time to time in your columns, have
proved entirely successful, the spec-
fed speed being greatly exceeded and
all previous records Gncluding those of
the Turbinia) having been broken, per-
haps / may be allowed to discuss Ger
tain points in connection with the fig
ures attained, which are of considerable
interest and Importance. We had not
ourselves thought of making a strict
comparison between the coal consump-
ton of the Viper at any particular
speed with that of other vessels of SIM
liar tonnage, as she differs in essential
particulars from all other vessels and
such comparison would be entirely
misleading unless accompanied by
fun statement of the principal features
of the vessels to be compared, with
their necessary bearing upon the re-
suits But, as other persons have
thought well to make an unqualified
comparison, I now propose to briefly
place the case on sound footing. and /
may add that the comparison is inter-
esting and instructive, especially to
those whose business it is to design or
to use fast vessels.
The trials Of the Viper have been
somewhat more elaborate than usual
for torpedo boat destroyers though
they do not by any means as yet cover
the whole of the ground They have
included coal consumption trial of
the contract speed of thirty-one knots
the mean speed during the three hours
being Bills knots, and the coal con-
sumption, as determined from the usual
hull resistance experiments, 2.3S pounds
per indicated horse power per hour, the
contract being not to exceed 2.5 pounds
per indicated horse power. The power
required for this speed is about two
thirds of the maximum for which the
engines and boilers We're designed, the
maximum being upward of 1890 ndi-
Gated horse power, which power has
been realized on preliminary, but Off
ctal, full power contractors trials, the
maximum mean speed then reached
being 36,S5S knots
The second official trial was a three
hours coal consumption trial, with the
air pressure limited to three and one
half inches, and carrying the full
weights as determined by the previous
trial under the usual admiralty condi-
lions.
A mean speed of 49, S3S knots was
maintained with about four-fifths of
the maximum power, the coal consump-
ton being at the rate of 249 pounds per
indicated horse power per hour.
The third official trial was the usual
twelve hours coal consumption trial at
cruising speed
In recent years the stipulated speed
on this trial has been increased from
thirteen knots to fifteen knots (this /
mention as the coal consumption of the
Viper at thirteen knots) The ascer-
tanned coal consumption of the Viper
on this trial was at the mean rate of
twenty-seven hundred weight per hour. |
1t should be mentioned, however, that |
Fl. M. S. Cobra. the second fastest ship !
afloat, with the same sized turbine en-
cines and similar in every respect to
the Viper, but loaded to service condi-
tons and having a displacement of 44G
tons or about sixty tors greater than
the Viper consumed on her official fif-
teen-knot trial 24.5S hundred weight per
hour. In her case the port engines
only We're used, the starboard engines
being dragged round by The propeilers,
and it is probable that the Viper with
ler less displacement would, when
Using one set of engines only, burn less
coal than the Cobra. AS, however, it
would be instructive to ascertain this
'esult definitely, 1t is probable that this
est will be made at an early date.
Now to the case in point.
A comparison has been made of the
coal consumption Of the Viper and the
Albatross at a speed of about thirty
me knots.
1t so happens that the two vessels
laVe the same displacement, and it is
acitly assumed in the accounts that
he horse powers necessary to drive the
wo vessels is the same, which is by no
means the case, for the following rea-