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Suggested Citation:"2. General Observations." National Research Council. 2002. 2002 Assessment of the Office of Naval Research's Air and Surface Weapons Technology Program. Washington, DC: The National Academies Press. doi: 10.17226/10594.
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2

General Observations

OVERALL ASSESSMENT

The committee found the overall ASWT program, as presented, to be reasonably well focused and clearly responsive to the FNC process. Even the D&I thrusts clearly focus on supporting one or more FNCs in the longer term. Furthermore, the quality of the work appeared high, the technical approaches were generally sound, and the results were often impressive, especially in light of the relatively modest funding levels.1 The committee identified several excellent S&T projects that fully satisfied all of the evaluation criteria established. These projects—guidance for projectiles, precision strike navigation, and weapons imagery link—were of high technical quality and appeared to be led by technically competent managers.2 The committee recommends that these excellent projects be continued and that sufficient funding, acknowledgment, and ongoing support be provided to ensure their successful transition into major programs.

The committee had some general observations on the future of naval air and surface weapons that overarch the specific findings and recommendations, which follow in Chapters 3 and 4 of this report. In particular, the committee was concerned with the ASWT program's strong S&T focus on near-term needs and the occasional pursuit of S&T in isolation from future operational requirements. These concerns are discussed in the next two sections, and new topics suggested for consideration in the future ASWT program are discussed in the last section of the chapter.

1  

It was noted during presentations to the committee that revenue from patents is a significant source of funding for the Naval Research Laboratory (NRL). To the extent that this finding can be validated, it is an interesting and impressive measure of the success of NRL in its D&I effort. While other elements of ONR might have less opportunity to follow the lead of NRL (and academia) in aggressively seeking patents and collecting royalties and licensing fees on those patents, the committee, nevertheless, believes there may be similar opportunities to enhance the overall D&I portfolio.

2  

Guidance for projectiles is an effort under the D&I gun weaponry thrust; the precision strike navigation and weapons imagery link efforts are found under the Time Critical Strike FNC.

Suggested Citation:"2. General Observations." National Research Council. 2002. 2002 Assessment of the Office of Naval Research's Air and Surface Weapons Technology Program. Washington, DC: The National Academies Press. doi: 10.17226/10594.
×

BALANCING NEAR- AND LONG-TERM NEEDS

As noted in Chapter 1, ONR began a major funding transition in FY02, when it attempted to bridge the gap between long-term “technology push” research (D&I) and short-term “requirement pull” development (fleet/force initiatives). The current approach to bridging this gap is the FNC process, which attempts to provide a smooth transition across the mismatch between the technologists and the requirements and acquisition communities, all of whom participate in the integrated product team overseeing each FNC.

While the FNC process for aligning and partnering these communities appears in principle to be very successful in focusing S&T investments and creating a clear path for transition to acquisition within the future years' defense plan, it has done so through an almost exclusive ASWT program S&T focus on air and surface weapons near-term needs, to the detriment of developing technologies for the Navy and Marine Corps after next. Moreover, FNCs focus on transition rather than technology, and this is reflected in the ASWT program as follows: (1) there is no 6.1 funding by Code 351 to address fundamental problems, limiting performance and important program areas such as automatic target recognition (ATR) and (2) D&I thrusts are predictably being tailored to fit and align with FNCs.3

Furthermore, there seems to be little or no systems analysis capability within the overall S&T planning process at ONR. While the committee was pleased to see the development of the enabling capabilities effort to serve as scenarios for some aspects of the ASWT program (e.g., TCS FNC), it was not apparent to the committee that any further analysis leveraged those enabling capabilities to understand the requirements for and merits of the technology being pursued. For example, attempting to increase gun ranges using large, double-tamped propulsive loads bothered the committee in that no systems analysis had been conducted to evaluate the utility and systems feasibility of such an effort. 4 Also, of concern was the committee's impression that some ASWT program efforts were not fully aware of synergistic opportunities presented by programs in other Services; for example, the U.S. Army heat-capacity lasers and the U.S. Air Force and government of Sweden programs in reactive materials.

As a result of these concerns, the committee believes that a program realignment will be needed in Code 351 if future naval air and surface weapons technology is to have a balanced S&T investment portfolio so it can meet both near- and long-term needs. In all three of its earlier assessments, NSB recommended in one form or another the need for systems analysis as part of an overall S&T planning process at ONR.5 Most recently, in its 2001 assessment of ONR's Aircraft Technology program, NSB

3  

The strategic choices made in selecting the largely 6.2 and 6.3 activity pursued by Code 351 means that the activity (from a technology standpoint at least) has a good chance of eventual deployment by the fleet; however, no ONR ASWT program efforts are being funded at the 6.1 level, and only $5 million of Code 351 aircraft funding is allocated for intelligent autonomy efforts. Interestingly, some of this 6.1 effort now being incorporated into the Autonomous Operations FNC appears to derive from small business independent research (SBIR) and independent research and development efforts. Nevertheless, the ASWT program's direct links to 6.1 appear to be relatively modest, beyond a general awareness that 6.1 research or its equivalent is often the ultimate source of transformational technology.

4  

Another example relates to the D&I thrust directed energy. There are many system and operational issues that must be considered for shipboard free-electron laser directed-energy weapon, including radiation and electrical power and volume requirements. The current program is aimed at demonstrating the feasibility of a scale-up to the 100-kW level, along with studies of radiation management and electrical power requirements.

5  

Naval Studies Board, National Research Council. 1999. 1999 Assessment of the Office of Naval Research's Air and Surface Weapons Technology Program, National Academy Press, Washington, D.C.; Naval Studies Board, National Research Council. 2000. 2000 Assessment of the Office of Naval Research's Marine Corps Science and Technology Program, National Academy Press, Washington, D.C.; Naval Studies Board, National Research Council. 2001. 2001 Assessment of the Office of Naval Research's Aircraft Technology Program, National Academy Press, Washington, D.C.

Suggested Citation:"2. General Observations." National Research Council. 2002. 2002 Assessment of the Office of Naval Research's Air and Surface Weapons Technology Program. Washington, DC: The National Academies Press. doi: 10.17226/10594.
×

recommended that a long-range strategic plan be developed to provide (1) a framework for future ONR S&T investments, including emphasis on D&I and (2) a vision for new capabilities, including advanced concepts at affordable costs. The committee believes that this earlier recommendation remains applicable today.

Recommendation: In collaboration with other Department of the Navy elements, ONR should develop a strategic naval air and surface weapons technology plan that will achieve a balance between near- and long-term goals. This effort should include collaboration with both the Marine Corps Combat Development Command and the Navy Warfare Development Command, given their concept-based approaches, as well as the help of the Office of the Chief of Naval Operations and the Naval Air Systems Command, given their influence on naval air and surface weapons technology needs. Such collaboration might even help to stimulate, evaluate, and transition new technologies to fleet experiments and expedite their transition to operational use. Moreover, systems analysis should be used as a means for developing this strategic plan as well as throughout the overall S&T planning process at ONR. Finally, as part of this strategic plan, the committee recommends that all projects relevant to an S&T air and surface weapons capability throughout ONR and the Department of the Navy be collectively reviewed, even though they exist in several functional organizations.

RESPONDING TO FUTURE OPERATIONAL REQUIREMENTS

The committee's first review criterion was the appropriateness of the ASWT program investment strategy within the context of Navy and Marine Corps priorities and requirements. In many thrust areas (e.g., precision strike navigation and cruise missile real-time retargeting), the ASWT program seemed to be responsive to operational requirements, while in other areas (e.g., gun weaponry and directed energy) there seemed to be a much weaker connection between the technology and the naval requirement.

An important example of a requirement is that for naval fire support. The committee was told that the projected concept of operations (CONOPS) for naval fire in support of Marine forces requires deep, accurate, high-rate, high-volume delivery of ordnance inserted as far inland as 200 nautical miles (nmi). These airborne units would not carry artillery for volume fire. Most targets will be time critical for one reason or another. Once the process time from surveillance to target detection, identification, and assignment is reduced, there are two basic ways to provide support fire and reduce the time to weapons on the target: the first is to minimize the weapon flight time from launch platform to target, the second is to loiter the launch platform or weapon close to the expected target-rich area. Almost all current Code 351 time-critical and precision-strike technology programs are focused on the second approach using cruise missiles or aircraft/uninhabited combat air vehicle (UCAV)-launched weapons. Two exceptions are the gun weaponry thrust, which is applicable to ranges of not much more than 50 nmi, and the hypersonic weapons technology project (under Propulsion and Aeromechanics), aimed at ship- and air-launched Mach 5 or 6 air-breathing cruise missiles with ranges in excess of 400 nmi.

The difficulty with the current emphasis on loitering weapon platforms or weapons for long-range TCS is limited payload capacity and limited endurance. The Navy has the ability to position platforms with very long endurance and with capacity for large volumes of sustainable fire in support of expeditionary forces deployed from the fleet.

The NSB's 1999 assessment of the ASWT program pointed out the obvious application and advantage of solid-rocket-propelled weapons at the longer ranges in lieu of trying to push gun-launched rocket-assisted projectiles or extended-range guided munitions (ERGMs) to ranges that would introduce

Suggested Citation:"2. General Observations." National Research Council. 2002. 2002 Assessment of the Office of Naval Research's Air and Surface Weapons Technology Program. Washington, DC: The National Academies Press. doi: 10.17226/10594.
×

many other problems (e.g., erosion and logistics). The committee is aware that the Naval Sea Systems Command (NAVSEA) is working on a naval version of the Army tactical missile system but believes this would offer only an interim and limited capability. The committee was told that there are two obstacles to the use of solid-rocket weapons for volume fire support: (1) the inability to provide an at-sea reload capability and (2) the limited number of launchers and the limited magazine space available onboard most surface combatants. In the committee's view, both of these obstacles are surmountable. Any long-range volume fire from surface ships will require solutions to both problems, yet there is now very little visible work under way to develop the required technology. Some high-payoff technology is sorely needed in this area.

The committee believes that ONR should take the initiative for some imaginative D&I work and analysis on ship-launched missile and stowage/launch concepts for the longer-range fire-support role. As one example, it is estimated that based on a propellant with a specific impulse (Isp) of 265 sec and a mass fraction of 0.85, a single-stage 9-in.-diameter missile less than 10 ft long with a launch gross weight less than 360 lb can accurately deliver a warhead equivalent to a 155 mm gun-launched projectile weighing about 90 lb to a distance of almost 200 nmi in less than 5 minutes. If a four-pack stowage and launch canister can be designed for individual missile cold launch and empty canister jettison, a stack of two four-pack canisters would fit in each existing vertical launch system (VLS) position.6 If, say, 32 of 64 VLS positions were assigned for fire support, there would be 256 (32×8) rounds in firing position exclusive of other magazine capacity. A single tier of these launch modules would be ideal for the fast littoral combat ship concept. A second example is a 21-in.-diameter, two-stage missile using the existing type canister and Mk 72 booster as its first stage and the 21-in.-diameter second stage currently under consideration for Standard Missile, third generation (SM-3) growth options. Such a missile with a launch gross weight (LGW) of 5,900 lb could deliver 1,400 lb of munitions to a distance of 375 miles (600 km) in less than 7 minutes. (This LGW is substantially greater than current Standard Missiles and would have to be examined for handling and plenum compatibility.)

Advances in rocket-propelled gun-launched projectiles have been impressive, providing ranges in excess of 50 nmi. Attendant to these achievements has been the development of microelectromechanical system (MEMS) inertial components and Global Positioning System (GPS) elements that appear capable of withstanding the gun launch environment. However, the committee believes, as it did in the 1999 review, that a longer range should not be sought for this technology. Longer-range fire missions are probably better handled by solid-rocket-propelled ballistic missiles. While the attendant barrel erosion problems, setback acceleration requirements, and logistic issues of a gun round that is more than 10 ft long (and requires double tamp loading) are interesting to work on, in the committee's view they are barriers to effective use in the longer range fire-support role.

It should be mentioned that two of the arguments used to justify pushing gun technology to provide fire support at ranges in excess of 100 nmi are the limited magazine space aboard combatants and the inability to replenish missiles at sea. Several presentations indicated that the Navy cannot reload a VLS

6  

The committee believes the cold launch of shipboard missiles provides additional flexibility and firepower. This capability, a variant of the system used for years in ballistic missile submarines, nuclear powered (SSBN) offers several advantages. One scheme would employ a gas generator and water reservoir in each canister to generate the steam pulse to eject the weapon. Such a capability would allow much more flexible ship configurations without the plenum requirements currently needed for VLS-based weapons. It would also allow weapon mixes with easier reload capability. Canted launchers could protect the ship from post-eject fallbacks and would allow stacking canisters within the same real estate, jettisoning spent containers or hang fires (missiles not obeying firing instructions) to allow access to lower weapon canisters if firing order is top missiles first.

Suggested Citation:"2. General Observations." National Research Council. 2002. 2002 Assessment of the Office of Naval Research's Air and Surface Weapons Technology Program. Washington, DC: The National Academies Press. doi: 10.17226/10594.
×

at sea. The committee is concerned that Code 351 assumes that this situation must continue. (In the 1960s, the FAST (fast automatic shuttle transfer) system was built and installed, but later abandoned owing to its complexity and many failures. These problems created a valid skepticism about such capabilities, but today's automation technologies offer solutions to many of the problems encountered back then.) While this is a logistics issue not directly in the purview of the ASWT program, it limits the program's choices. Today, it certainly affects the Navy's ability to provide sustained fire support with missiles. In the long term, the committee believes there will be an increasing need to use ship-based missiles for sustained strike and fire-support missions. To this end, the present limitations on at-sea missile reloading must be overcome. The committee believes, based on prior Navy work, that at-sea VLS reloading would be technically and economically feasible.7

Recommendation: NR should consider funding a significant D&I effort and a related analysis to address the emerging need for rockets for naval fire support. This future program should have the following components:

  • A new family of stowage and launching canisters that will allow cold launch steam or compressed-gas ejection of rocket-launched weapons from existing VLS-equipped combatants as well as from specialized new combatants. This effort should consider developing the ability to launch a volume-limited 21-in.-diameter, 21-ft-long missile round. It should also consider a configuration that would allow individual launch in the same manner of four 9-in.-diameter, 10-ft-long weapons.

  • A solid rocket weapon that builds on the integrated high-payoff rocket propulsion technology (IHPRPT) thrust and the excellent microelectromechanical systems (MEMS) precision-guidance work now being pursued by Code 351. This additional effort would investigate rocket-launched weapons of the type mentioned above to meet the future Marine Corps deep fire support requirements. Such weapons, cold-launched, could be carried by other types of combatants such as the littoral combat ship now in the concept development stage. A littoral fire support ship would be an interesting adjunct to the cold launching of weapons discussed above. Such a ship carrying a large number and mix of solid-fueled missiles and weapons in various sizes along with the self-defense weapon systems of other combatants could serve as an at-sea resupply ship for other combatants as well as a weapon launcher self-directed or from Aegis ships via cooperative engagement capability (CEC). Such a ship would be large enough to support positive handling schemes that might allow safe at-sea transfer and emplacement of larger weapons. The small, fast littoral combat ship concept could take advantage of this reload capability as could guided missile destroyers (DDGs) and other Aegis platforms.

  • A systems development and analysis effort addressing at-sea reload in the context of a specialized large-magazine ship capable of both resupply and direct launch of weapons. Such a capability would be valuable for sustained support of expeditionary forces in many scenarios. A littoral fire support ship with large magazines and many more launch positions could provide high-rate, high-

    7  

    For several years, the Naval Surface Warfare Center's (NSWC's) Port Hueneme Division has demonstrated a transportable rearming method (TRAM), estimated to be capable of reloading a VLS at a rate of 15 missiles/hr in sea state 5. In its 1997 Technology for Future Naval Forces study, the NSB stated that whether or not TRAM proves to be a satisfactory solution, the Navy should find some system for at-sea reloading (Naval Studies Board, National Research Council. 1997. Technology for the United States Navy and Marine Corps, 2000–2035: Volume 8: Logistics, National Academy Press, Washington, D.C., p. 14).

Suggested Citation:"2. General Observations." National Research Council. 2002. 2002 Assessment of the Office of Naval Research's Air and Surface Weapons Technology Program. Washington, DC: The National Academies Press. doi: 10.17226/10594.
×

volume, long-range fire support. With more deck area, it might also provide a stable base for facilitating at-sea replenishment of new cold-launched weapons as well as existing VLS canister designs.

RECOMMENDED NEW PROGRAM AREAS

The committee suggests four new program areas for ONR's consideration in the future ASWT program. The topics range from basic research to advanced technologies.

Compelling Problems of the Time Critical Strike FNC

As discussed in Chapter 4, the committee believes that none of the TCS FNC thrusts are likely to fail to achieve their objectives. Most appear to have a high probability of a successful transition into the acquisition process. However, while the TCS FNC thrusts appear to address specific limitations of current systems (or, in the case of gun technology, future gun systems), the committee was disappointed with the TCS FNC overall, because it does not aggressively address some of the more urgent problems of time-critical strike. Areas that need to be investigated include the following:

  • Improved decision aids that will accelerate the required analyses of the potential for collateral or unintended damage that must accompany each target nomination before weapon release can be authorized for a given target.

  • Improved sensor systems and processing algorithms to allow more efficient discrimination between targets and decoys and between military and civil targets.

  • New or expanded CONOPS and new command, control, and targeting systems for loitering weapons and the platforms (e.g., UCAVs) that might carry them.

  • New or expanded CONOPS for a precision, high-speed, surface-to-surface weapon that can reach its intended target from long standoff distances in times that are short compared with the dwell times of mobile or relocatable targets.

  • A more systems-oriented approach to the target recognition-weapon assignment chain by considering all potential sources of data that can be applied and robust means of fusing those data for effective and rapid correlation of scenes and viewpoints as they change with time. There exist tools and capabilities that should be but are not being applied to the current work, which is focused on today's weapon system CONOPS.

Offense-Defense Coordination and Deconfliction

Based on the information presented to the committee, Code 351 has no current or future efforts aimed at addressing offense-defense coordination and deconfliction. It is widely known that conflicts in the use of airspace will arise in intense actions, yet the doctrine necessary to help commanders resolve the conflicts has not yet been defined either by the Joint Chiefs of Staff (JCS) or by the Joint Theater Air and Missile Defense Organization (JTAMDO). Nevertheless, if the Navy and Marine Corps are to conduct expeditionary warfare successfully, their actions will need to be coordinated to avoid fratricide and other unintended effects. In many situations, the payoffs of the systems that Code 351 is developing will be negated unless better coordination is achieved. Accordingly, the committee recommends that ONR, in collaboration with the appropriate Department of the Navy offices, undertake to develop the technical means and CONOPS by which the Navy and Marine Corps could achieve the coordination necessary for expeditionary warfare, even in the absence of such means at the Joint level and in the other

Suggested Citation:"2. General Observations." National Research Council. 2002. 2002 Assessment of the Office of Naval Research's Air and Surface Weapons Technology Program. Washington, DC: The National Academies Press. doi: 10.17226/10594.
×

Services. The CEC, as it evolves with upgrades which integrate the surveillance aircraft (E-2C), offers a framework for providing the connectivity for a naval single integrated air picture and presumably could integrate Marine ground units as well to achieve total theater situational awareness.

Asymmetric Threats

The committee was briefed on concerns about asymmetric threats and the special requirements imposed by them. While the need for improved ship defense against asymmetric threats within the constraining environment of foreign waters was clearly conveyed, there was only a tenuous connection to activity in Code 351 thrusts. Layered defense is clearly needed with high probability of single-shot, single-burst kill using multispectral acquisition and tracking. One area that appeared to be directly applicable to the problem of small-boat or jet-ski targets coming out of the sun was the infrared sea clutter rejection work. Of particular interest in light of the constraints on rules of engagement within ports of call would be the application of nonlethal concepts that are currently in development in other Services, discussed in Chapter 3 under “Directed Energy.” The committee recommends investigating some nonlethal approaches in future Code 351 programs, or, at a minimum, integration of nonlethal approaches into systems in coordination with Code 353 (Expeditionary Operations Technology Division).

Automatic Target Recognition Fundamentals

The ASWT program-related efforts encompassing automatic target recognition (ATR) appeared to be focused on a valid near-term need—the ability to reduce the time from the acquisition of surveillance data from single-spectrum sensor assets to verified target recognition, validation for a strike decision, and then tasking the shooter in a form that the shooter can correlate with an aim point or what he/she will see as he/she approaches the target. There are four key problems with the specific application presented to the committee—the processing of F-18-carried shared advanced reconnaissance pod (SHARP) sensor data correlated with Global Hawk data to identify and assign targets in a cluttered environment. First is the correlation and fusion of area scenes from different sensors with different viewing angles, distances, optical and radio frequency (RF) spectrums, resolution, and display media. Second is the discrimination of potential objects of interest from normal terrain and vegetation, especially when camouflaged, based on unique signature characteristics. Third is placing those objects in the context of the area to determine combat identification for a strike decision, and fourth is providing the strike mission plan together with the data necessary for the shooter to approach, properly designate, and engage the target. The sense of the committee was that the recognition problem was being approached somewhat in isolation and without considering other parts of the system chain. In particular, advantage should be taken of multispectral images, special-purpose array processors designed for high-speed scene-to-scene correlation, and commercially available high-speed terrain-rendering engines to create common viewpoints for images from multiple sensor platforms.

In summary, ATR under harsh, deceptive, and dynamic environments remains a distant goal under Code 351 programs. There are many areas of fundamental research in other ONR programs that could have considerable impact, but they were not briefed to the committee. Even if they are addressed elsewhere, their omission from the Code 351 agenda slows the pace with which they might be incorporated into FNCs. The committee recommends that in cooperation with other relevant ONR activity, Code 351 accelerate the ATR program.

Suggested Citation:"2. General Observations." National Research Council. 2002. 2002 Assessment of the Office of Naval Research's Air and Surface Weapons Technology Program. Washington, DC: The National Academies Press. doi: 10.17226/10594.
×
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Suggested Citation:"2. General Observations." National Research Council. 2002. 2002 Assessment of the Office of Naval Research's Air and Surface Weapons Technology Program. Washington, DC: The National Academies Press. doi: 10.17226/10594.
×
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Suggested Citation:"2. General Observations." National Research Council. 2002. 2002 Assessment of the Office of Naval Research's Air and Surface Weapons Technology Program. Washington, DC: The National Academies Press. doi: 10.17226/10594.
×
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Suggested Citation:"2. General Observations." National Research Council. 2002. 2002 Assessment of the Office of Naval Research's Air and Surface Weapons Technology Program. Washington, DC: The National Academies Press. doi: 10.17226/10594.
×
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Suggested Citation:"2. General Observations." National Research Council. 2002. 2002 Assessment of the Office of Naval Research's Air and Surface Weapons Technology Program. Washington, DC: The National Academies Press. doi: 10.17226/10594.
×
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Suggested Citation:"2. General Observations." National Research Council. 2002. 2002 Assessment of the Office of Naval Research's Air and Surface Weapons Technology Program. Washington, DC: The National Academies Press. doi: 10.17226/10594.
×
Page 19
Suggested Citation:"2. General Observations." National Research Council. 2002. 2002 Assessment of the Office of Naval Research's Air and Surface Weapons Technology Program. Washington, DC: The National Academies Press. doi: 10.17226/10594.
×
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The Office of Naval Research (ONR) contracted with the Naval Studies Board (NSB) of the National Research Council (NRC) to establish a committee to review ONR's Air and Surface Weapons Technology (ASWT) program. The committee convened on May 14 and 15, 2002, and reviewed more than 20 science and technology (S&T) efforts that were presented as constituting the ASWT program. The committee then met separately on May 16, 2002, to formulate its findings and recommendations. This report represents the consensus views of the committee and is based on the information presented prior to and at the review, as well as on the committee members' accumulated experience and expertise in military operations, systems, and technologies.

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