Vice Admiral William S. Sims, Commander, United States Naval Forces Operating in European Waters, to Bureau of Steam Engineering
SENT: July 7, 1917. TO: Bureau of Steam Engineering.
Submarines operating in war zone generally run at speeds varying from one and three quarters knots to three knots (stop) WILKES exercised with British submarine running submerged at four to five knots (stop) Results generally poor both for directional and listening observations although the boat was recogni<z>able at maximum distance of about twelve hundred yards (stop) Advise against making further installations for present of the Submarine Signal Companies special equipment but strongly recommend continued and energetic experiment and development of same especially amplification of beat (stop) Study of noises made by auxiliary machinery of destroyers desirable (stop) Request results by cable of any recent test New London (stop) The information and recommendations in this cable based upon report by Lieutenant-Commander Castle who witnessed the experiments.
Source Note: Cy, DNA, RG 45, Entry 517B.