122 ON THE SUITABILITY OF CURRENT DESIGN OF SUBMARINES 
short time, probably 14 knots for a half-hour. This very high speed is desirable tactically 
for a spurt in intercepting a fast enemy. The long medium-speed submerged radius will 
be used to approach an enemy that is unaware of the submarine’s presence and therefcre 
sees no reason to change its course. 
Great stress has been laid in Captain Rodger’s paper on high surface speed. This is 
considered important for certain services that are being performed in the present war. For 
attack on warships, however, it is of secondary value. The reason is that a submarine 
must submerge immediately it sights an enemy vessel, else it will reveal its presence and 
thereby lose the opportunity to attack. From this time on it must approach awash or even 
submerged. It may be forced to travel 10 or 15 miles under water in order to deliver a 
successful attack. Surprise is a corollary to the submarine offensive and is the basis of all 
offensive strategy. In approaching an area where an enemy force may be operating, it may 
become necessary, for success, to submerge and approach from considerable distances, even 
as far as 20 to 30 miles, depending upon the number of patrol vessels with the enemy, the 
depth of water, etc. 
Submarine engines should be, above all, reliable. They are constantly called upon for 
double duty—driving the Deisel and charging the batteries. In demanding high surface 
speed, much of this reliability is lost. The consequence is machinery breakdowns, and that 
naturally means total unavailability. I know of nothing more abject than a submarine 
with disabled engines. Too much emphasis cannot be placed on the fact that all activities 
of a submarine, even the preparation of the food, depends upon the readiness of her engines, 
which are the source of all her power. 
Even after advocating high surface speed for submarines Captain Rodgers does not 
permit them to use it. “Owing to their essentially defensive nature,” he says in the paper, 
speaking of German submarines, “they were obliged to lie in wait in positions where shipping 
would come to them.” If they must only lie in wait, why is surface speed given the major 
importance? Now if these submarines lying in wait had high submerged speed and conse- 
quently considerable submerged radius in both time and miles, many vessels which would 
otherwise escape would be brought within torpedo range. Furthermore, with reliable en- 
gines the submarine will reach its station and be able to lie in wait. 
It is fairly well known, and the writer has received corroborative testimony recently, 
that Germany is building all her submarines of the offensive type; and that she still aspires 
with sufficient numbers of such vessels to overthrow Great Britain’s control of the world’s 
communications. With this accomplished, of what value will be the command of the sea? 
A great surface fleet cannot be maintained indefinitely if this control is lost. It will defeat 
itself by its very inertia and expensiveness. 
Our problem, in the event of war, is to attack the enemy’s control of communications, in 
order to safeguard our shores from invasion by sea. 
The idea of establishing a defensive cordon of coast-defense submarines lacks imagi- 
nation in the conduct of naval war. It is a defensive policy calculated to do great harm to 
the nation. National policy may be defensive, but, once war is declared, our action must 
be offensive. A defensive war strategy leads to nothing. The members of this Society 
can do no greater service to the state than the instilling of the offensive idea in the conduct 
of naval war throughout our country. Its psychological effect upon our naval policy will 
be of great moment. 
