Go Back Report # 262


            The final version of this case, is a combination of two prior reports. The first is Hydrospace by Martin Caidin, © 1964, which follows. Then Ed Hyde's article U.F.O.'s --At 4500 Fathoms! Man's Illustrated (Mar. 1966) which I do not have yet, and these two are combined by Ivan T. Sanderson in his book, Invisible Residents © 1970 


The Thing

Before we visit the liquid depths of hydrospace, I feel compelled to make the observation that we have not yet touched on what is perhaps the greatest fascination of the now inevitable trek into the sea.

            There is something else awaiting us in the depths---something of which we hear very little, and encounter even less frequently, in this technological and computerized age of ours. There is mystery.

            Such as may be found in one instance selected from many. This one happened near Puerto Rico. . . .

            A group of American research ships were cruising on the open sea, the scientists aboard the vessels conducting a variety of oceanographic tests and measurements. Within one ship, the sonar operator clapped his hands in disbelief to his earphones, pressing them tighter against his ears while he studied his instruments with a suddenly intense stare.

            For he had picked up the sound of a submarine, driving hard, driving swiftly through the seas. And it was deep! The sonar man could hardly believe the evidence of his equipment. But he could hear distinctly the noise of that single, mighty screw that pounded and hammered its way through the deeps with a speed that was almost unbelievable. It was all there; the instruments were perfect, and their indications were absolutely clear.

            Every ship in the research group was requested immediately to shut down all engines. They complied at once. Aboard every ship scientists trained their instruments toward that great undersea vessel churning the deep into froth.

            The sound hammered its way through the water. The instruments within and below every research ship picked up the invisible target; the men traced the sound and tracked it with precision.

            In the sonar rooms, at the control and            panels, engineers and scientists stared at one another with widened eyes. Again they turned to their instruments; again they checked with the men of the other vessels. There were startled exclamations. The instruments provided a definite, precise cross-check.

            That throbbing sound, the churning screw that drove with fierce energy . . . was coming to them from a depth of 27,000 feet.

            Its speed seemed unbelievable. At its depth, that unseen and incredible thing---whatever it was ---endured a pressure of nearly 2 million pounds per square foot!

            And it was moving with a speed they could estimate only as being

equal---perhaps superior---to that of the fastest nuclear submarine known.

            The implications were staggering, and the next morning the sonar echoes of that unbelievable thing seemed unreal---like an undefinable nightmare stalking the clearly defined corridors of science.

            Then . . .  they heard it again.

            They listened with their sensitive instruments and their scientific devices, and with exquisite care they tracked the thing and monitored their instruments.

            At different times, they heard, and tracked it, for several days.

And then it was gone.

            They could arrive at but one conclusion.

            Deep, deep down, five miles deep into the realm of hydrospace, there existed a form of life of which we had not the slightest conception, and which must be possessed of physical strength and driving energy that beyond the understanding, or even the imagination, of man.

This reference: Hydrospace by Martin Caidin, chapter 2, pp. 26-27, © 1964    

Then Ed Hyde's article U.F.O.'s --At 4500 Fathoms! Man's Illustrated (Mar. 1966) which I do not have yet.         

Then combined into Invisible Residents:


            Sometime in 1963, the U.S. Navy conducted some exercises to train personnel in the detection and tracking of underwater craft. The maneuvers were conducted off Puerto Rico in the Atlantic some five hundred miles southeast of the continental United States. All reports seem to agree that there were five "small" naval vessels concerned, but in more than one account, the aircraft carrier Wasp, is stated to have been the command ship. There appear also to have been a number of submarines engaged in these exercises, and all vessels were intimately linked by advanced electronic communications systems. There were also aircraft, at least one of which trailed a detection device a little below the surface of the ocean from a line, while flying at very low altitude. The submarines are said to have been "fixed" for what is somewhat mysteriously called "silent running," a performance that cries out for further exposition.

            There then occurred a rather special and particular uproar which, at least as far as I have been able to ascertain, was initiated as follows: A sonar operator on one of the small vessels, otherwise listed as a destroyer, reported to his bridge that one of the submarines had broken formation and gone off in what appeared to be pursuit of some unknown object. This operator did not, of course, know if this was a "plant," since the maneuvers they were engaged in were exercises designed to train personnel in detection of enemy craft, and in such exercises, decoys must of course always be employed. However, this operator's report was not at all within the limits of any such simulation. Trouble was that said unidentified subaqueous object was traveling at "over 150 knots"!

            The deck officer on watch immediately reported to the skipper, said to have been a lieutenant commander, and this officer was not amused. Nonetheless, after calling his communications boys on the intercom, he got in touch with the command vessel, the Wasp, but was further frustrated to find that their radio intake was virtually jammed with similar reports coming in from all the other ships and from the sonde1 (sic) -trailing aircraft. Then comes a curious note from more than one of the reports that I have. This is to the effect that no less than thirteen craft (including submersibles and aircraft, one must suppose) noted in their official logs that their underwater tracking devices had latched onto said high-speed submersible, all of which is said to have immediately been reported to C.O.M.L.A.N.T. in Norfolk, Va. At this point, all the reports become somewhat vague and obscure. Various numbers of people, in various numbers of ships, are alleged to have observed or heard the sonar blips caught by their own operators, and all to have concurred in the fact that this object was being driven by a single propeller at more than 150 knots.

            The world record for a propeller-driven surface craft is 200.42 mph, but this was with a Rolls-Royce-engined hydroplane. The record for a diesel-engined surface craft is 60.21 mph. The all-time high was achieved by Sir Malcolm Campbell in his turbojet-engined Bluebird K.7, at 328 mph. The fastest speeds for submerged submarines have been achieved by the Skipjack class of tear-drop-shaped nuclear vessels of the United States Navy. The semiofficial record is 45 knots (51.8 mph). Thus, the object recorded above beat anything that we can do at the present stage of our technological development by nearly four times in speed.

            But that was not the whole story. It is said that the technicians kept track of this thing for four days, and that it maneuvered round about and down to depths of 27,000 feet. The record dive for a standard submarine is 6,250 feet, achieved by the U.S. Aluminaut on the 12th of November 1967, twenty miles off the west coast of Grand Abaco Island in the Bahamas. The record for mere submersion is, however, the descent to 35,800 feet made by the little Trieste in the Pacific in 1960.  However, this craft could hardly move along at all, while the Skipjacks cannot go down to more than a sixth of that depth. In other words, this thing was literally out of our world. What was it? Perhaps a more pertinent question is, are these reports true? As I have said, I have been unable to obtain any confirmation of them. The authors who originally wrote of them are known and are respectable writers of factual matters, and they have specialized in underwater investigations, and apparently with much help and advice from naval authorities. This is thus, at least as far as I am able to state as of the time of writing, a dead end. We are then presented with the corollary question as to how possible and/or probable any such things as the item described above might be. Here we enter a really extraordinary world that, except in a very few abstruse quarters, has not up till now been brought to the attention of the general public. First, it transpires that this is by no means a unique case. Not only do the authors identified above constantly state that there have been numerous other reports of a similar nature by and to our Navy since that date, but that still others have been reported by several other navies. Second, there have been equally surprising reports made by both naval and commercial ships’ officers, mostly giving names and dates, and going back more than a hundred years. Moreover, of those incidents which have occurred since this classic, several are outstanding and are very properly documented.                                                                                                             

This reference: Invisible Residents by Ivan T. Sanderson, pp. 20-23, published 1970

Original reference: Martin Caidin, Hydrospace, New York: E. P. Dutton, 1964

Secondary reference: Ed Hyde, “UFOs-at 450 fathoms!”, Man's Illustrated, March 1966

Note #1: “sonde” I believe this to be a typo for “sonar” in because D is close to A on the keyboard and E is next to the R.        

UFOCAT PRN – 73270 [DOS: ??-??-1963]

UFOCAT URN – None   Hydrospace by Martin Caidin, New York: E. P. Dutton, 1964

UFOCAT URN – None   "UFOs-at 450 fathoms!" by Ed Hyde, Man's Illustrated, March 1966

UFOCAT URN 073270  Invisible Residents by Ivan T. Sanderson, pp. 20-23, published 1970

UFOCAT PRN – 75993 [DOS: ??-??-1964]

UFOCAT URN 075993  UFO Nachtrichten, June 1971   

Atlantic Ocean

Location as given in the text “some five hundred miles southeast of the continental United States” (Florida) would place the ships more in the area of Cuba and Haiti rather than Puerto Rico.-CF-


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