The history of undersea warfare weapon development leads to two basic conclusions: the weapons developed for the attack submarine have suffered from serious deficiencies in numbers,
effectiveness and reliability in the operational environment, while the weapons developed for the
strategic ballistic submarine have been satisfactory in all respects.
It follows then that an examination paths used in the development of submarine weapons produces reasons why paths ended in such disparate results. analysis shows that in the case of ballistic
missiles, the optimum missile characteristics were determined. Then the missile was sized out
and the platform designed to complement the weapon. Incompatibilities between the ballistic
weapon and its submarine platform were identified and compromises made. The compromises usually
favored the weapon even at the cost of platform effectiveness. As a result of this straightforward approach, the deterrent value of the strategic submarine system is referred to in terms of the weapon used the number of warheads that can be brought to bear on certain targets, the maximum range and accuracy, the confidence inherent to weapon use and the vulnerability of the system including the
missile.
In contrast, the fast attack submarine weapon system is described in terms of platform parameters 1. e., submarine speed, depth, radiated noise levels, and performance relative to similar foreign submarines. The characteristics of the attack submarine’s weapons — her torpedoes — as to tubes for launching and targets available are evidently secondary to the importance of platform capabilities. Design compromises between the platform and the weapon favor the platform rather than the weapon. This is exemplified by the reduction from 10 launch tubes over the years to 4 launch tubes, the placing of tubes well back from the bow, the lack of emergency modes for launching weapons and the static number of loadout torpedoes — while the size of the submarine platform was more than
tripling.
An analysis is thus needed to determine what platform characteristics best complement antisubmarine or antiship weapon characteristics — whether torpedo or missile -to produce the most efficient use of our submarines for the destruction of enemy surface and submarine forces. The efficiency of the attack submarine should then be measured against targets and the circumstances under which they would be taken under attack.
The MK39, the first wire-guided torpedo was too slow to be used operationally and hence was
dropped in favor of the MK37. But the MK37 eventually proved too slow for the newer Soviet
submarines. A dual-platform torpedo was then called for, mainly to save money — but also on
the premise that a submarine’s torpedo is little different than a torpedo used by a surface ship.
Actually the MK!48 was designed to meet the criteria of an over-the-side launch by a surface
ship. The target would be aware of the launch, therefore the torpedo need not be covert. But it
required high speed to catch an alerted target, which in many cases would immediately activate
torpedo countermeasures. In my Bu Ord job in the early sixties we pushed the EX10 for antisubmarine use — not recognizing that enemy surface ships would be possible targets. At that time, the Soviet surface fleet was little to be worried about. But 1 ts submarine force of over 300 units
was. Thus, making the MK48 a dual-purpose torpedo — secondarily to sink surface ships — didn’t
seem critical. But as the MK!48 was developed in the late ’60s, it became apparent that while the
weapon was optimized for submarine targets it was bound to suffer in effectiveness against a Navy
with efficient surface warship targets. And while it was being designed to be effectively used
primarily by surface ships, the covert, mobile character of the nuclear submarine presented such
a different set of characteristics as to make effective compromises between the weapon and the
vastly different types of platforms almost impossible. It seemed then that the best answer
was to develop the MK48 for purely submarine use. Although only submarines now use the MK48 torpedo, it wasn’t so designed. Indications were that another type of torpedo should be developed for
surface ship targets when they became a valid threat.
It is not apparent that the characteristics of the nuclear attack submarine has in any way been
driven by the MK48 torpedo. Today’ s submarines are little different than the nuclear submarines
which used the MK37 torpedo.
Because there seems to be little relationship between the present torpedo design and the design
of the platform which employs it, new torpedo characteristics should be responsive to the
answers for comparable questions that resulted in the successful marriage of weapon and platform in
the Trident program.
The questions which need asking appear to include :
- What are the major surface and submarine targets which have to be distinguished for weapon planning purposes?
- What are the numbers of targets of each type which will exist when the weapon is operational?
- What is the probability of target countermeasure efforts and their possible effectiveness estimate?
- What is the importance of warhead size to the type of targets to be destroyed? (The great distance between outer and inner hulls of recent Soviet submarines highlights this point.)
- What is the type of terminal homing versus the sophistication of the target?
- What is the optimum attack range for various classes of targets?
- What is the tradeoff with missiles as a result of the these factors?
- What technolgoy is available now or in the near future to meet the desired characteristics
of a torpedo for the next decade? - What is the estimated quantity of torpedoes required by the attack submarine force the stockpile, based on an expenditure rate which reflects the hardness of modern targets and the wastage on false or inappropriate targets?
The answer to questions involving these elements should result in identifying those weapon
characteristics and the numbers to destroy or immobilize a target population which needs to be well defined.
Whereas the SSBN and its SLBM were evolved from analyses similar to the foregoing and resulted in
a platform which complements a weapon designed to best destroy a specific target complex, the
nuclear attack submarine which is optimized for detection and classification of targets rather
than for destroying them will probably require changes to accommodate a new torpedo for the ’90s
that is responsive to the factors just noted.
The foregoing questions have been addressed in depth in the past, but not within the framework of
a platform/weapon system analysis comparable to that employed in the development of the strategic
submarine/missile system.
The Falkland Islands War demonstrated how an inflexible straight-running, short-range, loud
torpedo can have a platform, the nuclear submarine Conqueror, which with its great covertness and
high mobility complemented the torpedo’s shortcomings. Conversely, the quiet, long range,
wire-guided Tigerfish torpedo which was also on board the Conqueror, if used against a high speed
submarine would require a platform of great covertness and mobility like Conqueror. What is
suggested by this Falkland’s experience is that the nuclear submarine can normally attain a highly
favorable attack position against a surface target, thus allowing use of torpedoes far simpler
and less costly than the present MK48 torpedo.
Past torpedo war time experience shows that: there was a critical shortage of weapons at the start of each conflict; there were critical failures of supposedly well tested vital components, i.e., exploders and depth control mechanisms; and torpedoes were not rapidly produced under wartime conditions.
An awareness of torpedo history plus a good understanding of the important elements in
deriving a concept for a torpedo leads to: an understanding of how the submarine platform can
be designed to optimize the effectiveness of its weapon; a recognition of the futility of developing a dual-purpose weapon, a good definition of a single-purpose antiship torpedo and a different single-purpose anti-submarine torpedo; and finally, that compatible platform/weapon systems lead to less costly solutions for the destruction of the total targets available to attack submarines.
At present, there is great interest in the direction to be taken for the next attack submarine. If one starts with a concept for a best weapon — whether it be torpedo or missile — for the next SSN, and reflects those attack submarine characteristics which make the weapon most efficient, then the U.S. is certain to continue its dominance of the undereas and surface areas of the worlds oceans.
R. C. GILLETTE
