PRAENUNTIUS FUTURI "II"
By J.V. Ferrero, LT, USN
Jim Ferrero was the Engineer on Albacore at the time of writing this piece. This article was published in a submarine "Combat Readiness" publication and in a SubLant Information Bulletin in the 1956-57 time frame.
When I was editing this article for inclusion on the website, Jim wrote the following: "When I wrote that paper, it was based upon the "War" potentials at that time (the mid 50s). Our submarine force was just beginning to increase in numbers of attack subs and ballistic missile subs (the boomer force). The Navy was building towards 100 attack subs and 40+ boomers. The USSR, like the Germans, made the submarine their capital ship and built a force structure of over 500 subs of various configurations. My ideas were also tempered by how the sub was used in WWII. I envisioned sub-to-sub conflicts with many targets for our boats plus the USSR ASW force. Since that time, much has changed and technology advances (the digital world) made my concept good. Also the EDO world, lead by Rickover, negated the "fighter sub" idea. Based upon today advances in aircraft integrated weapon systems, such as in the F-14 and F-15, I suggest we not add this paper to the Albacore readings. I don't think our audiences would find it interesting. Of the ideas contained in this paper, I can only think of one which materialized--the conformal sonar array."
"By the way, many of the weapons used in my paper some were under evaluation by SUBLANT'S SUBDEVGRP 2, located at that time in New London. The data I got on the D-40 eval came from my skipper, Jon Boyes, who was involved in it on his previous sub. The missile came from an Army program, mounted in small tubes attached to the sail, and could be launched submerged (much like today's VLS used for Harpoon). It was to be used by the sub against enemy ASW forces. A like(similar) eval used Sidewinder missiles. The rest of the weapons you questioned were sub-to-sub and sub-to-air missiles in various stages of development, now in the fleet. I do not know the status of the integrated weapons control systems concept on today subs. Having been personally involved in today's airborne multi shot systems from a single weapon platform, I tend to believe that the sub force is years behind in multi shot system development. They are years behind in man-machine relationships - but then maybe it isn't important since the target rich environment afforded by the USSR is no longer available."
I disagree with Jim about not adding this paper to the website. I think it provides a well thought out concept on how to use the tactical advantage provided by a nuclear ALBACORE.
(Note: Words in italics are the editor's.)
During the past few years, great strides have been taken in submarine hull design and power plants. The NAUTILUS has convincingly proved the use of nuclear power to be feasible, practicable and acceptable. During this same period, ALBACORE has proved the need for an idea hull form and adequate control systems. When these ideas are brought together in the form of the SKIPJACK (SSN 585), this new submarine will have the possibilities of being the most formidable weapon of modern warfare. Based on the performance of ALBACORE, she will have the following tactical capabilities:
a. Turning diameter -- 165 yards
b. Turning rate -- 50/sec
c. Rate of depth change -- 25 ft/sec
d. Acceleration (2 - 26 knots) -- 2 min 40 sec
e. Hydrodynamically stable at all speeds
f. More speed for less shaft horsepower (7,360 shp = 26 knots)
g. Speeds in excess of 35 knots predicted for 15,000 shp.
In order to adequately use this vehicle at hand, it is necessary that we investigate a fire control system that is entirely new. It is the purpose of this paper to discuss our present submarine fire control systems in respect to the "NEW" submarine and then to present a system which could use the potentialities of our new weapon to the greatest advantage.
The fire control systems presently being employed by our operational submarines are modifications to basic systems used during World War II. This system was built around a commanding officer getting information from his periscope, radar or sonar. This information was then put into a torpedo data computer and a lead angle for the torpedo would result. The fire control party involved some 15 to 18 men. Ship control was maintained by two enlisted men and an overseer, the diving officer. This system worked well for the type of war which the U.S. fought. It was based on a slow moving surface craft which was designed to submerge and which could gain a favorable firing position. Our enemy did not have a good sonar or good radar. With this system, only one target at a time could be taken under fire.
With the advent of the nuclear ALBACORE, this type of fire control system would not utilize the capabilities of the weapons being made available. There would be too much dead time between the C.O.'s decision and the results desired. This new vessel is just too fast and too maneuverable to be hindered by inefficient human amplifiers. Our potential foe has sonar and radar which we believe to be equal to ours. Take, for example, the AN/SQS-4 Sonar; it has active ranges out to 10,000 yards. Radar can detect a snorkel or periscope at long ranges. Just think of trying to get through our present screens using the tactics of World War II. We are going to have to shoot our way through the screen in order to get at the main body. We surely cannot do this with our present systems! Or consider being engaged by an enemy sub in a dogfight beneath the seas. That sub could easily have the same capabilities of our nuclear ALBACORE. Due to these factors and current weapon developments, the old fire control system would not fill the bill.
It is therefore necessary that some new concepts be accepted in the submarine service. Consider the analogy between aerial dogfights and SS vs SS in a dogfight. It is going to be necessary that the Commanding Officer or the Executive Officer become the submarine pilot. We cannot accept the dead time that is inherent in our old system. We must have almost the same conceptual FCS as that of an all-weather fighter pilot. All equipment must be at the pilot station in order to conduct an efficient attack.
Many new weapons are presently being designed and evaluated for submarine use. The D-40 missile, SLIM, SAM, and hydroduct will be used by our new submarines. These missiles do not lend themselves to the type of FCS which we HAD. The D-40 missile, for example, will permit a submarine to launch a missile submerged. This missile will then become airborne and can be directed at nearby helicopters or surface craft. (Editor's note: The anti-helicopter missile is still a submariner's dream.) The hydroduct is being designed to run about 20,000 yards at 100 knots. (Editor's note: The Mk 48 ADCAP - ADvanced CAPability torpedo approximates these capabilities.) This weapon could be used very effectively in submarine dogfights with other subs or surface craft. Plans are presently being made for a missile (SSM - Surface to Surface Missile) which can be launched submerged, become airborne and travel some 60 to 80 miles to hit a distant task force. (Editor's note: Submarine launched HARPOON and TASM - TOMAHAWK Anti-Ship Missile -missiles did become deployed on SSNs.)
Presently, the primary mission of our submarine force is anti-submarine warfare. For that reason, it is necessary that our FCS be made to accomplish this mission.
It is proposed that an experimental fire control system as described herein be considered for installation on the ALBACORE during Phase III of her test period. This paper is not designed to go into all of the "nuts and bolts" of this system, but rather to establish the parameters for it. In the interest of consolidating this new idea with present shipboard control installations, this system will fit in with the present experimental diving panel, automatic pilot, and automatic helm, all produced by Sperry Gyro Co.
The fire control problem for the Navy's all-weather fighter aircraft is identical to that of a submarine except for the media in which each operates. The systems installed in these aircraft have several desirable features and therefore will be used as the basis for the submarine system. This particular system is compact and will save much space on a pursuit submarine.
Basically, this new system must accomplish two things: (1) Locate submerged or surfaced targets and provide information enabling the S/M pilot or autopilot to maneuver into a firing position; (2) Direct a lead-pursuit or lead-collision attack with the weapons previously discussed. In the past, due to the slow submerged speeds, it was necessary to attack our targets from ahead. This resulted in a lead-collision type of attack. With the higher speed and more maneuverable submarine, an attack from any sector may be made. That is the reason for the use of a lead-pursuit attack.
The system will have the following modes of operation: (a) Autopilot controlling, (b) Pilot controlling, (c) Pilot control to override autopilot signal. As in the all-weather fighter aircraft, it is necessary that we have automatic control systems. These systems must be directed by certain target inputs to a computer and the end results monitored by the S/M pilot.
The heart of this FCS will be good sonar equipment. It is necessary that it have the following characteristics:
(a) Passive range of 50 miles
(b) Active range of 10 miles
(c) Bearing accuracy of:
+/- 1° at 10-50 miles
+/- 1/4° at 0-10 miles
(d) Be faired in with ALBACORE hull design
The sonar gear desired will probably be large and bulky. However, there is no reason why it cannot be built into the basic hull configuration of an idea submarine form.
Reference was made previously to a computer. An analog computer, such as the one used in the Navy fighter plane, must be developed for use with this system. The computer will be capable of accepting initial manual inputs of target's angle-on-the-bow and estimated target speed during the passive sonar phase. During this phase, it must solve for a course that will close the target's track. The solution will be presented on a sonar PPI scope at the S/M pilot's station as a virtual target. When active sonar is used, an exact target's course and speed, based on steady or intermittent range information, will result. Once again, the solution will be presented on the S/M pilot's attack scope.
The sonar PPI scope at the pilot's station will present the following information:
(a) Direction to steer.
(b) Target's bearing.
(c) Range rate (0-75 knots)
(d) Range to target (when active)
(e) Three range selections (50 mi, 10 mi, 2 mi)
(f) An artificial horizon in order to show whether the target is above or below the S/M.
In order to aid the pilot during his attack, certain auxiliary devices will be needed. A visual or audible system should be used to tell him: (1) When within the selected weapon firing range, (2) Weapons are ready to fire, (3) Test depth is being exceeded, and (4) A break-away point indication so as to avoid a collision with the target.
The diagram that follows proposes the arrangement for this new system. It is shown as being integrated with presently installed equipment. In this manner, many of the sub components of each system may be eliminated and much space may be saved.
Now that all the components of this new FCS have been set forth, it is necessary to describe how it might be used. We therefore must assume that our Commanding Officer or Executive Officer will be the pilot. He will be in charge of running the entire approach and attack from one position, called the S/M attack station. Only one man makes the attack.
When a target is detected by passive sonar, it will be tracked for a short period of time by a sound operator. Based on observed information, the S/M pilot will crank in an assumed angle-on-the-bow and speed. This information will go to the computer. It will solve a maneuvering board problem and send the solution, a course to steer, back to the attack scope. The course may either be steered by the autopilot or the pilot. Periodic single ping ranges will be attempted by the pilot. When active contact is made, the pilot will go to active sonar. With steady or intermittent range information, the computer will present a real target, or targets, to the pilot. Target pip will be maintained in the center of the scope in order to close the target. The scope will also present to the pilot information previously discussed. These inputs will also go to the weapon's computer which will be continuously putting information into our weapons. When within firing range, a buzzer will let the pilot know that he can fire at any time.
The question may arise as to what would be done "if" a helicopter had contact on such a submarine trying to attack a carrier task force. The C.O. could launch a D-40 missile against such a vehicle! Another question might arise as to multiple targets. It is exceedingly easy with this system to take a new target under fire. It is only necessary for the S/M pilot to lock onto another target and fire his weapons.
In retrospect, it can be seen that our present submarine fire control systems are inadequate for our new submarines. By modifying such equipment, the desired results cannot be obtained. It is necessary that a complete, new system be designed based on ideas contained herein. The new submarine is useless unless we have efficient means of employing its potentialities.
The ideas presented here may sound as if we are in the "Buck Rogers" era -- well, we are.