Detecting AndRanging /SOund Navigation And Ranging
little WW-2 story from the newspapers of the day follows:
Noises Confuse Sub Crews ON Look Out for Sounds of
of Deep Grunt, Purr, drum find Grind Their Teeth With
Surprising Effect, Men at Earphones Of Undersea Craft Find; Navy Records
WASHINGTON, Aug. 19 (AP). -- U. S. submarines turning corners
at 10 fathoms or so have pulled up in surprise and wonderment at hearing such
raucous sounds as "honk, honk! beep, beep!--g-r-rrrr!"
with the earphones who listen to what gees on while their craft is slithering
through the briny deep, often confuse these noises with the hum of enemy
propellers, and signal for a quick stop, look, listen.
But, as it
turned out today, the eerie underwater traffic noises often are caused by
and wildlife service of the Interior Department has reported to its chief,
Secretary Ickes, that little fishes are as noisy as dishes, when
said the F. and W. service in a formal report, "actually grunt, purr, drum,
grind their teeth and make a medley of other sounds that create strong
underwater vibrations even when inaudible on the surface."
The F. and
W. service, aided and abetted by the Navy, has made a series of recordings of
fish noises which are being drummed into the ears of submarine "listeners" so
that they will know the difference between an ichthyological burp and a Japanese propeller.
experts," said the report to Mr. Ickes, "obtained their most surprising results
with the toadfish, a common species of the Atlantic coast known for its ugliness
and its bad temper. Although advised by fish and wildlife service biologists
that the toadfish is an important sound-producer, the investigators were
unprepared for the volume of its voice which they said compared in intensity
with a steam-boat whistle."
capable," the report went on, "of making drumming, grating, or grunting noises
are found both in fresh and salt water in all parts of the world. Whether fishes use their voices to attract, the opposite sex, as a
feeding call, or to express general contentment like a cat's purr is not
reference: (Wilmington, Delaware) Journal-Every Evening, August 19, 1943, p. 10,
Nice to know we can
detect small fishes and obviously, large undersea submarines. Now how about
those “U.F.Other” craft
is for the accumulation of cases that deal with Radar or Sonar so that we can
see from them, what to expect in “returns”. Admittedly, the greatest number of
cases will come from Radar inasmuch as it encompasses aerial UFOs as well as
those on the surface.