The TRIDENT Program
With this report, the Submarine League’s Government Affairs Committee begins a series of overviews of specific major submarine development programs. This article on the TRIDENT program stems from a meeting of the Committee with RADH Ted Lewin, the Director of the Strategic Submarine Division or OPNAV (OP-21).
The Committee’s first question was about the current status of the SSBN force. Admiral Lewin noted that in the period since GEORGE WASHINGTON made the first POLARIS patrol in the fall of 1960 there have been over 2400 SSBN patrols and the strategic submarine force now numbers some 28 POLARIS/POSEIDON class ships and 7 operational TRIDENT boats. The 28 POLARIS/POSEIDON boats are of the 616, 627 and 640 classes which originally numbered 31 but the SAM RAYBURN was decommissioned last year to stay within the SALT limits on SLBH launchers, and two others are being dismantled now. Additionally ten boats of the 598 and 608 classes have either been decommissioned or are serving as attack boats. NEVADA (SSBN 733), a TRIDENT, is due to be delivered in the fall of this year, with more TRIDENTS to be delivered by December or 1990 for a rate of about one a year. Two TRIDENTS were authorized in each of the FY 75 and 78 budgets.
Twelve of the 28 POLARIS/POSEIDON boats have been backfitted with the 4000 nautical mile range TRIDENT I missile (C4) and are currently operating out of Kings Bay, Georgia. A tender provides for their maintenance, but later a large, modern base presently under construction will be the east coast version of the present base at Bangor, Washington. The other 16 POLARIS/POSEIDON boats still carry the 2500 n.m. POSEIDON (C3) missile. They operate out of Holy Loch. Scotland and Charleston, South Carolina. (Rota, Spain was discontinued as an SSBN forward site a number of years ago.)
In the Pacific, with the phase out of the short range POLARIS missile, SSBNs no longer operate out or Guam. The new construction TRIDENTS with their greater range C4 missiles, operate from the base at Bangor.
The exact size of the TRIDENT submarine force has not yet been determined, but the expectation s for about 20 new TRIDENTS. The exact force size according to Admiral Lewin, should be determined by requirements for replacement of the present SLBM force, future arms control agreements, the balance required within the strategic TRIAD, and the perceived need for survivable strategic forces.
The TRIDENT submarines of the OHIO class are built to accept the much larger TRIDENT II missile (D5) when it becomes operational. At 130,000 pounds, it weighs twice as much as the shorter and thinner C4. It can be recalled that as the original 41 POLARIS/POSEIDON boats progressed from the 30,000-pound A1 and A2 single warhead missiles to the 35,000-pound A3 with its multiple warheads, only relatively minor ohanges were required to refit the older boats to the newer missiles. Major differences in ship structure however, resulted from re-engineering of the SSBN to accommodate quieting improvements and provide for more space forward.
The POSEIDON boats’ ballistic missiles weigh 65,000 pounds aod their diameter was 74 inches instead of the 54 inch diameter for the POLARIS missiles. Tube liners were removed from later classes of SSBNs to accommodate the larger diameter, but the growth in weight could not be tolerated by the earlier boats. Such problems however are not envisioned for the 726-class TRIDENT boats, and eventually all will be back- fitted with the DS missile. That will still mean that the u.s. SSBN force will have three types of missiles since there are no current plans to backfit the C4 into those boats now carrying the POSEIDON missile.
Production of C4 missiles is ended, with the NEVADA (SSBN 733) being the last of the TRIDENT I subs. A restart of C4 production to extend this capability beyond the first eight TRIDENT subs would cost several billion dollars for a new run of missiles and about one billion more to acquire equipment to go into the ships. The whole process would also take longer than that now needed to reach 100 units with the DS missile.
The mix of POSEIDON, TRIDENT I and TRIDENT II systems does not offer the flexibility of a single system but the TRIDENT systems give increased range, increased accuracy and increased payload over the POSEIDON. The TRIDENT II’s DS missile moreover responds to the need for a ballistic missile with a hard target kill capability. This would hold at risk those hardened facilities (missile silos, etc.) that the Soviets prize highly. The DS will permit significant increases over the C4 in payload and a significant improve-ment in accuracy but its fully loaded range is comparable to the fully loaded C4.
The new D5 missile will use all the available space within the launch .tube, have greater propulsive power, and its total weight will be greater.To achieve hard target kill capability, larger and heavier high-yield warhead, designated the HKS is being developed. Thus for the same number of multiple warheads there is no significant increase in range over the C4.
The D5 missile will also be capable of carrying the same MK4 warhead used on the C4 missile. Thus, with a full load of MK4s, the DS will have a substantial increase in range over the C4’s 4000-mile range.
The D5 is currently in full scale engineering development and all initial system testing is proceeding satisfactorily toward a first flight test early in 1987 from Cape Kennedy. The ninth 726 class submarine, USS TENNESSEE (SSBN 734), to be delivered in late 1988 will be used for the evaluation launches from an SSBN. The first Demonstration and Shakedown Operation is expected in 1989. That SSBN will then be the first of the big boats to be based at Kings Bay in Georgia.
The first West Coast operation for the DS will probably happen about 1994 — out of Bangor, Washington. By 1989 the DS missile production line should be up to speed and about six missiles per month produced for as long as it takes to outfit the entire 726-class.
The evaluation of the DS was aimed at roinimizing technical risks, shortening the developcent period and containing overall program costs. The DS missile itself is not just an enlarged C4. The missile’s electronics, guidance system, rocket nozzles and post boost control are all new designs. Other features, such as the thrust vector controls, are scaled up from the C4. The rocket propellant is a technical descendent of the MX development program — and that had its origins in the original C4 program.
Other elements of the complete TRIDENT II system however are evolutionary from the earlier TRIDENT I program. The launcher retains the C4 launch control system but requires a new gas eject system to launch the much heavier D5. On the other band, the navigation subsystem will use an electrostatic gyro for navigation instead of as a monitor and will have such new sensors as a velocity-measuring sonar and a gravity-sensing system in order to meet the improved accuracy specifications. In the fire control system, the same basic computer architecture is used but the memory is greatly expanded.
Overall, the operations to date of the TRIDENT system were characterized by RADM Lewin as “superb”. He said that the 40 patrols and over 45 successive, successful missile launches in the last three years have shown that the boats and missiles, with their support structure, are all highly reliable and noted that the new TRIDENT submarines are both faster and quieter than the design specifications called for. High reliability of the system was a key objective and can be seen in the improved maintainability built into the TRIDENTs, their better integrated logistics support systems, and their improved shore based facilities which were designed from the ground up as a part of that goal.
The TRIDENT subs have special accesses for removing and reinstalling equipment without having to cut the pressure bull or clear massive inter-ference in the submarine. There is a very large logistics hatch around the familiar man-sized batch and inside that logistics batch there are no major equipment or ventilation lines or cable runs that have to be moved in order to get whatever in or out of the ship. In addition, the process of repair and maintenance is enhanced by the creating of a TRIDENT repairables pool. The use of complete spare “modules”, such as a pump, can be offloaded and the spare immediately put in as a replacement so that the offloaded piece of equipment can be repaired, tested, and quality-checked in the ship before taking its place in the repairables pool. Logistical loading of provisions and consumables is also done on a pre-planned basis and utilizes containers that go through the logistic hatches.
The total support aspect of the shore based facilities can be seen in Bangor, with home port, refit site and off crew training all on the same base. This colocation provides obvious advantages while both the Blue and Gold crews can work on their TRIDENTs during a refit period.
The patrol cycle reflects this built-in efficiency. The cycle consists of about 95 days with the refit being allotted 18 days, the refresher training and final loadout 7 days, and the patrol itself being about 70 days long. That in itself is not very different from the POLARIS/POSEIDON routine but the real difference shows up in the overhaul cycle. Overhauls will probably still take between 12 to 18 months but the frequency between them has been stretched out to 10 years. That means that OHIO, the first TRIDENT. will be operating until 1991 and the realized time-at-sea portion of the boat’s life will be up to about 66J as opposed to about 55J for POSEIDON boats.
Admiral Lewis summed up the TRIDENT development program. stressing the efforts that have been made to look for cost-saving initiatives and to use off-the-shelf hardware. In discussing contractor competition in the strategic submarine program, Admiral Lewin noted that there is an effort to have TRIDENT constructed at Newport News in addition to their present sole construction at the E.B. division of General Dynamics.
Within the SSPO managed strategic weapon system there are six major areas in which contractors are now working on the TRIDENT II program. They are: NAVIGATION, Sperry, assisted by Autonetics and G.E.; FIRE CONIBOL, General Electric; LAUNCHER, Westinghouse; HlSSILE/REENTRY, Lockheed, assisted by Hercules Thiokol, CSD-UTC, and General Electric; GUIPANCE, Charles Stark Draper Labs, assisted by G.E., Raytheon, SKD and HAC. INSTRUMENTATION, Interstate Electronics Corp.
Admiral Lewis also stressed the importance of the continuing and ongoing SSBN Security Program which his office oversees in order to assure the highest possible degree of survivability for the strategic submarines during their operation. It is the business of that program to assess all potential threats and insure that adequate counter-measures are in place or are being developed to be ready when the threat might be operational. In looking at ASW threat technology, both acoustic and non-acoustic are examined and the security program secures the assistance or the most capable members of the scientific community as well as strategic programs’ own technical starr. About $50 million per year is put into this comprehensive program of analyses, consulta-tion, examination and development in order to keep ahead of the threat to U.S. strategic submarines.
Admiral Lewin stated most emphatically that there is no forseeable breakthrough in ASW technologies over the forseeable future. He further said that the Intelligence Community shared in that assessment. The point or the program is not to stand on any such determination but to continually survey the spectrum of possibilities, then when any particular technology shows potential, to develop counter-measures for defeating this threat.
