The Platform Environment of 2015+
During the three days of this symposium, you ’11 hear a lot about the future from many perspectives. This morning you heard from our distinguished group of keynote speakers about the submarine’s role in preparing and interacting in the future battlespace. To begin the day tomorrow, Dennis Bushnell, a futurist, will talk about the Information Technology Revolution, its impact on the future and some alternative approaches to future warfare. Later tomorrow morning, we’ll take a look at future submarine payloads (Editor’s Note: see the next article in this issue.) in Lora Weiss’ session on 1he Submarine as the Ultimate Asymmetric Threat. Thursday we’ll hear about 1he Submarine in Netcentric Warfare in Brian Sharkey’s session. Later that day Admiral Studeman will paint the picture of Threats of the Next Century. These will all affect the submarine platform.
Even before this year’s Submarine Technology Symposium began, you’ve heard views of the future and discussion of needs from the Defense Science Board report of last summer. This past fall DARPA and the Navy signed a Memorandum of Agreement entitled A Project to Revise Payloads and Sensors of Attack Submarines. Several months later, DARPA solicited industry ideas “to determine how payloads, related sensor technologies and the supporting platform design of U.S. submarines should be reconstituted … to maximize their effectiveness through the 2020 time frame … “. As you are aware, several teams are now funded to develop their id~ over the next 18 months. All of these id~ for improved submarine presence in the battlespace affect the platform.
Across these myriad opinions, options and opportunities for the future, there is a common thread, the submarine. The submarine is the enabler. The submarine is the means by which payload, sensors and their delivery systems (e.g., missiles, UUVs, ASDS) are delivered covertly to and sustained in the theater of operations. The submarine, the Defense Science Board concluded, is a key and enduring element of the future naval force-a crown jewel in America’s arsenal. Our focus for the next several hours is the submarine, The Undersea Platform for Future Maritime Dominance.
Do we profess to know what that future platform should be? No, although you’ll hear some ideas. We do see some glimmers of where to go, in part, based on where we’ve been.
The Historical View
Forty years ago we were designing and building submarines at a rapid pace. We designed and built new ships for new missions or made changes in existing designs to improve on the way we performed the same mission. More recently, the SSN 688 Class illustrates both of these points. As technology became available. the class was continually improved to perform it’s mission, and the design change to add Tomahawk enabled an entirely new mission capability.
Our history also says that the platforms require design commitments early in the design cycle and that only minor changes can easily be accommodated in their 30-40 year life. While the Virginia class is the first class to challenge that view with its modular design that is ready to accommodate technology insertion, many earlier examples point to the difficulty of platform modification to support emerging missions and technologies. Consider the USS GEORGE WASHINGTON, USS PARCHE, USS KAMAHAMAHA and the addition of VLS to the SSN 688 class, all had significant platform changes driven by the need for new missions that were unanticipated at the time of initial design. All of these modifications required a significant effort and had to be done during a major shipyard availability.
History, therefore, gives us this lesson-our platforms must be flexible, not only in design and construction and ability to infuse evolving technologies (as Virginia Class), but flexible in their payload. Payload flexibility allows the ship to perform in a variety of missions at any time, i.e., mission flexibility. In essence, we need to change the way we look at the platform, not as a product, but as the service it performs. We also must recognize that we are in a period where we are not designing many new submarines consequently. flexibility must be included in those that we do design. Our design view must shift from the platform cen1ric design to a mission centric design; not just for our present missions but for our future missions as well. We also must take from history the lesson, that no matter how well we think we’ve envisioned the missions of tomorrow. we will be imprecise. For tomorrow, we must be able, quickly and affordably, to adapt for both known and unknown missions, years before the missions occur. We need to be conceptually adaptable today for the mission of tomorrow. As we all know. anything that does not or cannot adapt becomes extinct.
Just how do we do this?
The Path to Platform Adaptability and Flexibility
First, we must be prepared to expand beyond our traditional platform paradigm of a conventional single hull with cylindrical sections. There is a growing belief that a double hull is the correct approach for the future. An obvious, key aspect of a double hull approach is the ability to make use of the space between the hulls and the additional hull surface area. Double hulls enable greater flexibility in the design of the inner pressure hull and the hydrodynamic outer envelope. The pressure hull can be optimized for structural, structural-acoustic and arrangement considerations while the exterior hull is optimized for hydrodynamic and stealth requirements. Locating the main ballast tanks ‘along the hull, between the annulus, shortens the ship and moves it closer to the optimum hydrodynamic length/diameter ratio.
Central in the approach for mission adaptability lies in driving platform flexibility from the outside with an outside-in design philosophy while optimizing the interior volume design. The outside-in approach for payloads, sensors, stealth and other design features, allows a consistent interior volume for a variety of mission approaches, thereby gaining the maximum in platform affordability. A guiding principle of this approach is to minimize the ship impact of internal upgrades while incorporating system level upgrades (sensors and payloads) externally where ship impact would be minimized.
Internal improvements have come a long way. Virginia class has design and construction flexibility and forward-fit technology insertion flexibility. We need to continue to make the inner volume technology insertion friendly. Beyond common interior volumes for a number of submarines, commonality of interior systems and components across multiple Navy platforms and programs also leads to Navy-wide affordability.
Outside-In design for external weapons and sensors relies heavily on a plug and play approach, like that so successfully demonstrated in the Virginia class Structurally Integrated Enclosures for onboard electronics. The concept of universal weapons modules and sensor packages with common platform interfaces (i.e., plugs) will greatly enhance flexibility.
As we have created new designs in the past, we have been very well served by staunch, thorough attention to the lessons from the past. With the necessity to assess and indeed implement more drastic design changes in a force of fewer ships, it is even more imperative that we build on the past lessons and retain sound design assessments.
Our platforms need to be flexible in theater, adapting to changing mission and situations. We also must move into a platform of platforms, mother-ships with adjuvant vehicles and progressively smaller emerging platforms. Our platform adaptability can foster mission flexibility and affordability by allowing our least expensive platforms to be used in the highest risk areas.
While the conclusions are some months away, a likely outcome of the ongoing DARPA/Navy Payload and Sensors program, will be a strong emphasis on adaptability and flexibility of the platform.
Technology today supports extending the modular flexibility of ship design into the life cycle of the ship. At the August 31, 1998 meeting of the Submarine Technology Oversight Council held at Electric Boat, Electric Boat presented how new technology will be able to support Life Cycle Modularity in the future, resulting in a Plug in Play compatibility for major sections and modules of future submarines.
Admiral Bowman amplified that theme in his recent article Submarines in the New World Order that appears in the Spring 1999 issue of Undersea Warfare. I quote from the Admiral’s article:
“Modular construction is the most cost-effective and operationally supportable means of providing for technology insertion into our new submarines. Significant modularity is already embodied in the design and construction of the new Virginia (SSN-774) class attack submarine. This design will facilitate planned technology insertion over the life of the class. In designing follow-on submarines, these modular concepts will be carried to their logical conclusion, to yield maximum flexibility in operation, economy in procurement and construction, and improvement in our modernization rate.
” With modular construction, we will also be able to deploy significant payload variations in our submarines using a single basic design. The modular architectural approach implements a basic, standardized structural shell that contains the nuclear propulsion plant and ship control functions, along with fundamental self-defense capabilities. Variable payloads can then be configured as plug-and-fight modules that would mate with the basic hull form, using standardized electrical and mechanical interfaces. These SSNs with optimized special payloads must preserve the submarine’s core advantages of stealth, mobility, and endurance and retain their important multi-mission capability. But the added flexibility to substantially enhance a chosen mission area-or set of mission areas-would offer a significant advantage over what I’ve called our traditional Noah’s Ark submarine design concept, in which small numbers of everything are carried aboard each submarine all the time, potentially to accomplish any conceivable submarine mission.
” A truly modular design would permit unprecedented flexibility for operational commanders to tailor their fleets.”