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Synopsis of Workshop Sessions

SESSION 1
FEBRUARY 27-28, 2013
WASHINGTON, D.C.

For Session 1, the workshop planning committee sent all presenters the following guidance on the desired format and content of presentations:

Tables of potentially rewarding high-energy laser (HEL) and high-power microwave (HPM) technologies and systems that are being developed that could be relevant to the Air Force, particularly for defensive applications. For each technology and system, a brief description and its expected performance. Please also provide the period (time line) of R&D [research and development] and testing and when a decision about deployment might occur. If available, please also provide the suggested number of systems that would need to be acquired and the cost of such a system (including development costs).

Wednesday, February 27, 2013

Welcome and Introductions

Gen Ronald E. Keys (USAF, Ret.), Session Chair

Gen Ronald Keys opened the meeting with an overview of the terms of reference for the workshop (Appendix B). He suggested that the workshop objective be viewed as providing useful input to the Air Force on the following key questions:

  • What is the root cause, or causes, for why directed-energy weapon (DEW) systems are not being adopted for Air Force applications? Why are the products from R&D programs not being operationalized? Is it, for example, because:
    — The technology is not yet ready;
    — The DEW alternatives are not sufficiently better than other options (e.g., projectiles); and/or the DEW alternatives are not competitively affordable (including the cost of engineering them into current platforms, etc.)?
  • Does the technology work in the “mud, blood, and beer” of real-world operations, not just in the laboratory?


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3 Synopsis of Workshop Sessions SESSION 1 FEBRUARY 27-28, 2013 WASHINGTON, D.C. For Session 1, the workshop planning committee sent all presenters the following guidance on the desired format and content of presentations: Tables of potentially rewarding high-energy laser (HEL) and high-power microwave (HPM) technologies and systems that are being developed that could be relevant to the Air Force, particularly for defensive applications. For each technology and system, a brief description and its expected performance. Please also provide the period (time line) of R&D [research and development] and testing and when a decision about deployment might occur. If available, please also provide the suggested number of systems that would need to be acquired and the cost of such a system (including development costs). Wednesday, February 27, 2013 Welcome and Introductions Gen Ronald E. Keys (USAF, Ret.), Session Chair Gen Ronald Keys opened the meeting with an overview of the terms of reference for the workshop (Appendix B). He suggested that the workshop objective be viewed as providing useful input to the Air Force on the following key questions: • What is the root cause, or causes, for why directed-energy weapon (DEW) systems are not being adopted for Air Force applications? Why are the products from R&D programs not being operationalized? Is it, for example, because: — The technology is not yet ready; — The DEW alternatives are not sufficiently better than other options (e.g., projectiles); and/or the DEW alternatives are not competitively affordable (including the cost of engineering them into current platforms, etc.)? • Does the technology work in the “mud, blood, and beer” of real-world operations, not just in the laboratory? 18

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• What kinds of issues need to be addressed to facilitate adoption? — Tactical issues—the technology works but is not tactically useful (superior to alternatives) — Cost issues — Intellectual acceptance issues—operational practitioners do not understand the benefits, do not see DEW solutions as a better way of operating In Gen Keys’s opinion, DEW technology has to win its way onto the battlefield. It must add value by doing something better than non-DEW options can, or something that they cannot, do. It has to have a reasonable cost structure and offer affordable capability. Proponents must answer the questions: “Where does it fit?” and “What Department of Defense (DoD) capability gap does it fix?” Air Force Champion’s Vision for Directed Energy Dr. Janet S Fender, Chief Scientist, Air Combat Command (ACC) Dr. David Robie, Office of the Chief Scientist, ACC Dr. Fender and Dr. Robie prepared abstracts of their presentations for inclusion in this report, which have been incorporated below as Box 3-1 and Box 3-2, respectively. Rapporteur Comments: In addition to the points made in Dr. Fender’s abstract above, her presentation and the interactions during and after it with other workshop participants raised the following points that are of particular relevance for themes that emerged during this session and the workshop as a whole (see Chapter 2). • Have the Air Force and the DEW R&D community taken advantage of the unique advantages and capabilities of directed energy—not viewing it as simply a bullet- replacement? • Have Air Force programs been addressing the most critical operational challenges and national challenges? For example, aircraft self-defense, although important in the long term, may not be the biggest national/Air Force challenge in the near term. — Dr. Fender and several other participants suggested that DEW technology development aim at high-priority missions. — Another suggestion, made by Gen Keys and seconded by several other participants’ comments, was that the R&D community ought to seek functional requirements for which DEW systems are best option. For example, do not seek a general requirement to integrate [high-energy] lasers into aircraft. Rather, according to this line of thought, the community would do better by making the case for DEW as a solution for an important functional requirement. • Dr. Fender’s point that successful demonstrations have been viewed as stepping stones to a next generation of technology advancement, rather than leading to an operational capability, evoked many comments and related discussion. A number of participants agreed with one participant’s response that the DEW R&D community needs to get products operational, not just “continue kicking the can down the road 19

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on when useful capability will be ready.” (Related comments and discussion recurred frequently enough throughout the workshop to make this an important theme; see Theme 1.4.) Several other participants thought there could be strong “user pull” for DEW systems, if it were shown to provide compelling solutions [for Air Force capability gaps or emerging threats]. But the solutions have to be affordable, and there must be a credible maturation plan for them. BOX 3-1 Directed Energy: An ACC Perspective Dr. Janet S Fender, Chief Scientist, ACC Airborne DEWs and adjuncts offer potentially significant asymmetric advantages as well as opportunities to realize innovative concepts, including deep magazine weapons, electronic warfare, novel imaging, and secure high-bandwidth communications. Although the Air Force has identified gaps optimally filled by DEWs, executable technology-maturity plans lag tech need dates for integration into future systems. Furthermore, investment strategy is complicated by the lack of a top-level Air Force perspective of highest-priority needs best met using DEWs. Exquisite lethal and nonlethal capabilities of laser and high-power microwave technologies have been demonstrated in realistic environments since the mid-1970s. However, each resounding successful demonstration was viewed as a stepping stone to a next-generation system with more advanced technology rather than an initial capability for operations. Therefore, the preponderance of Air Force investment in DEWs remains in exploratory and advanced research and development rather than technology maturity. Additionally, mutually beneficial partnerships among services and DARPA have been difficult to develop. Now in an era of austere budgets, a DoD-wide coordinated effort is critical to bring DEW capabilities into operations effectively. BOX 3-2 ACC Directed Energy Enabling Concept Dr. David Robie, Office the Chief Scientist, ACC Currently, a number of directed-energy applications will address the most significant mission gaps and needs of the Air Force. These applications include (1) high-power microwaves for counter-electronics applications, (2) high-energy lasers for airbase defense, (3) lasers in concert with electro-optical sensors for target location and identification, (4) laser communications, and (5) high-energy lasers for air superiority missions. Each of these applications is evaluated, assessed, and system-engineered to provide advanced capabilities in a high-threat environment. Finally, each concept is focused on the practical, cost-effective, and technically mature employment of these technologies. 20

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Air Force Research Laboratory (AFRL) Initiatives Dr. Robert Peterkin, Chief Scientist, Directed Energy Directorate, AFRL In his introduction, Dr. Peterkin noted that his presentation does not cover AFRL work on Blue Force defense against Red Force DEW threats. The concepts for employment he presented for the near, mid-, and far term are based on developing a fundamental understanding of targets’ vulnerability to directed energy. He described how AFRL works from measures of effectiveness for a potential system (objective system), derives subsystem technical performance measures by decomposing the full system into subsystems, and establishes science and technology (S&T) programs to solve problems in achieving those performance measures. Transitioning the AFRL results to products requires working with industry, and AFRL needs help in transitioning results into near-term DEW products. In the area of narrow-band HPM systems for counter-electronics applications, Dr. Peterkin discussed the Counter-electronics HPM Advanced Missile Project (CHAMP) Joint Concept Technology Demonstration (JCTD) and its SuperChamp follow-on. The key to a long- range counter-electronics application is to concentrate the energy in a narrow frequency range in short pulses. He described how AFRL uses the Joint RF Effective Model (JREM) to optimize firing location and aim-point and to predict probability of kill (pK) for targets. JREM was used in developing CHAMP prior to the system’s flight testing. A single CHAMP missile can engage multiple targets and achieve multiple functional kills. In the CHAMP JCTD, the recharge time between engagements was on the order of tens of seconds. Among the concepts studied was the use of multiple engagement passes (fly-bys) to increase the functional effects on the same target. SuperChamp, the follow-on work to the CHAMP JCTD, has a near-term objective of extending the CHAMP counter-electronics capability to operationally relevant ranges. Its mid- term and far-term objectives are to deliver frequency-agile counter-electronics and cyber/electronic effects from greater distances using other platforms. MAXPOWER is AFRL’s high-average-power HPM system for counter-improvised explosive device (IED) use. The objective is to detonate all classes of IEDs at safe ranges from mobile systems, without prior knowledge of IED location. A test version was deployed to theater for a 1-year operational evaluation. Dr. Peterkin also discussed the use of a quasi- continuous wave (CW) millimeter-wave system as a counter-personnel (nonlethal) active denial system (ADS), for use in driving ground-based personnel away from a clear zone around ground-based assets without employing lethal force. Turning to HEL systems, Dr. Peterkin presented and discussed a conceptual graph of the timeline for technical risk reduction for airborne HEL concepts versus the relative sophistication and specific power of each application (Figure 3-1). 21

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FIGURE 3-1 AFRL laser system concepts and timelines. SOURCE: Robert Peterkin, Chief Scientist, Directed Energy, Air Force Research Laboratory, “Assessment of Directed Energy Research and Development for U.S. Air Force Applications,” presentation to the workshop on February 27, 2013. For “hard kill” laser lethality, the important concept is fluence (energy per unit of area irradiated), rather than power of the emitted beam (kilowatts) or the irradiance (power per unit of area irradiated). Irradiance may be relevant to sensor kill when the laser beam is within the working frequency band of the sensor (in-band sensor kill). Beam quality, spot size, and dwell time are all relevant to pK for hard-kill lethality. Dr. Peterkin discussed how these parameters relate to the challenges for development of antimissile laser defense systems for aircraft and surface ships. Imaging anti-aircraft missiles present a more sophisticated and more difficult-to- counter threat than EO/IR missiles. AFRL and DARPA are collaborating on a concept for a high-energy electric laser on a large aircraft. This program was enabled by substantial DARPA investment in the HELLADS program. AFRL is also participating in the first four industry efforts of the Robust Electric Laser Initiative (RELI), led by the High Energy Laser Joint Technology Office (HEL-JTO). High Energy Laser Joint Technology Office Initiatives Mr. Donald Seeley, Acting Director, HEL-JTO Mr. Seeley prepared an abstract of his presentation for inclusion in this report; it is incorporated below as Box 3-3. 22

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BOX 3-3 HEL-JTO Initiatives Mr. Donald Seeley, Acting Director, HEL-JTO The High Energy Laser Joint Technology Office (HEL-JTO) was established in 2001 as an office within OSD. The mission of the office is to support the designated senior OSD official HEL programs by establishing priorities for the HEL programs, coordinating the programs among the services and agencies, and ensuring that these programs are consistent with the priorities identified in the official’s planning and programming activities. In addition, the HEL-JTO manages a portfolio of technology programs to advance the state of the art in HEL weapon system development; maintain the industrial base for HEL-related technologies; and educate current and future scientists, engineers, testers, and warfighters on HEL technologies and systems potential. The HEL-JTO portfolio consists of laser source development, laser beam control technologies, laser lethality sciences, modeling and simulation, satellite and airspace deconfliction, and educational initiatives. Currently, the major initiative for the HEL-JTO is the Robust Electric Laser Initiative, which will dramatically improve the efficiency and beam quality and reduce the size and weight of electrically powered laser devices that can be ruggedized for military applications. U.S. Army DEW Initiatives at ARDEC Mr. Charlie Freund, Acting Chief, Directed Energy Branch, U.S. Army Research and Development Command, Armaments Research, Development and Engineering Center Mr. Freund’s presentation provided an overview of DEW efforts at the U.S. Army Armaments Research, Development and Engineering Center (ARDEC). The Sparrow Sentry System for Personnel is an HPM application for screening people at portal control points for personnel-borne IEDs. It resulted from a series of down-scopes to the original concept, which was for a IED route-clearing role. The system was 100 percent effective in testing, but in 3 years of deployment there was never an active detonation (individuals were warned of the screening system’s presence). ARDEC is also working on a portable version to screen vehicles at entry control points for IEDs or vehicle bombs and a miniaturized version for screening personnel. Another route-clearing concept in development is the Laser Induced Plasma Channel technology, which works by ionizing air in a channel to an IED target, along which an electrical discharge is sent to detonate the IED from a safe standoff distance. Solid State Active Denial Technology (SS-ADT) uses a 95 GHz HPM beam to drive personnel away from an area to be protected by heating their skin to an intolerable level. The technology is being considered for both fixed-site and vehicle-mounted applications. SS-ADT has considerable SWaP advantages over the Army’s current Active Denial System. A handheld version of the technology is also under development. Funding for the SS-ADT technology is from the Joint Nonlethal Weapons Directorate (JNWD). 23

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U.S. Army DEW Initiatives at the Space and Missile Defense Command (SMDC) Dr. Kip Kendrick, Chief, Directed Energy Division, U.S. Army Space and Missile Defense Command, Army Forces Strategic Command Dr. Kendrick described work on a RELI-class HEL system (35 percent laser efficiency) with an advanced beam control system that allows it to fit on a Stryker-class Army vehicle for base defense against rocket, artillery, and mortar fire (counter-RAM). RELI uses a fiber bundle solid- state laser that has the advantage that repairs can be done in the field. The concept for this system was included in the recent Indirect Fires Protection Capabilities II (IFPC II) Analysis of Alternatives (AoA) for the base-defense counter-RAM role. Dr. Kendrick described how this technology has evolved from previous Army involvement in the Tactical High Energy Laser (THEL) and Joint High Power Solid State Laser (JHPSSL) programs. He then discussed the Army’s ongoing role in the HEL-JTO’s RELI program and the Army roadmap for HEL R&D. The IFPC II AoA resulted in selection of a missile system even though the HEL system scored well. In light of that choice by the Army Training and Doctrine Command, the workshop participants discussed with Dr. Kendrick his views on the hesitance of the warfighter community to move forward with operationalizing DEW concepts. He emphasized the importance of developing credibility with the warfighter community while development is ongoing. DEW is a paradigm shift for the user, he said, and the S&T community needs to address warfighters’ concerns on issues such as supportability and reliability. In response to a question, he said it is important to address doctrine and concept of operations (CONOPS) for a DEW application. Defense Advanced Research Projects Agency (DARPA) Initiatives Dr. Richard Bagnell, Strategic Technology Office, DARPA Dr. Bagnell’s presentation described DARPA programs for the High Energy Liquid Laser Area Defense System (HELLADS) and for the Laser Weapon System Module (LWSM) of HELLADS. A key point he made about the LWSM is that the system’s footprint is driven by the power and thermal management subsystems necessary to meet the duty cycle and magazine requirements. Discussion of Day 1 Presentations Gen Ronald E. Keys (USAF, Ret.), Session Chair Gen Keys asked the participants to comment on the day’s presentations, going in a clockwise direction around the table from his left. After Session 1, the rapporteur organized his notes on this discussion under the following five emerging themes of the workshop: • Are the right applications and CONOPS for DEW being considered? • Does DEW have credibility with the warfighter? Does the warfighter understand and accept the opportunities that DEW systems might provide? • The Air Force DEW R&D community may need to stop kicking the operational capability can down the road. 24

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• What are the potential paths forward for transitioning Air Force DEW science and technology products to operations? • What are the priority R&D opportunities? The first three of these themes subsequently became Themes 1.1, 1.3, and 1.4, respectively, in the overview of themes and major points from the workshop as a whole (see Chapter 2). The fourth theme evolved into Theme 3 in the overview, and the fifth theme became Theme 3.1 in the overview. Individual participants’ comments related to these five themes are represented in the overview. Thursday, February 28, 2013 Welcome and Introductions Gen Ronald E. Keys (USAF, Ret.), Session Chair In his comments to open the second day of presentations and discussion, Gen Keys offered the following observations: • DEW proponents should be careful to differentiate between early adopters and beta testers. Based on his experience, Air Force warfighters may have been scared off DEW by too often being used as unwitting beta testers, when they thought they were being early adopters of an operational capability. (See Theme 1.3.) • It will be important to get the right CONOPS that fit the capability of a DEW technology or system. As an example, he recalled how a HEL system demonstrated for the B-1 bomber and became irrelevant when the CONOPS for the B1 changed from the original design for low altitude and high speed to the current CONOPS of flying at medium to high altitude. (See Theme 1.1.) • It is okay, he suggested, to present an HEL program as a technology maturation program, but do not sell it as leading to a fieldable weapon system if that is not a likely direct outcome if the proposed program is successful. (Relevant to Themes 1.2 and 1.3.) • Air base defense is a natural good fit for a big-laser (i.e., large size, weight and power, or SWaP) defense system. Another key application could be anti-access. (In subsequent discussions, particularly during Sessions 2 and 3, Gen Keys emphasized that air base defense is not currently seen by ACC and others as an Air Force mission. See Theme 2.) OSD Initiatives Dr. Spiro Lekoudis, Research Directorate, Defense Research and Engineering, OSD Dr. Lekoudis prepared an abstract of his presentation for inclusion in this report; it is incorporated below as Box 3-4. 25

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BOX 3-4 Topics in Weapons Research and Engineering Dr. Spiro Lekoudis, Research Directorate, Defense Research and Engineering, OSD A discussion relevant to aircraft self defense is relevant and appropriate, as technology proliferates and the sophistication of potential adversaries increases with time. Examples of such trends are (1) the challenge to the U.S. superiority in electronic warfare, (2) digital signal processing is expanding, (3) networked passive-active sensor combinations are appearing, (4) software-driven waveform generators are coded, (5) weapon seekers are gaining spectral diversity, and (6) counter-countermeasure capabilities and advanced jamming techniques are evolving. In addition, modern integrated air defense systems are networked, mobile, and redundant. Advanced high-speed air-to-air radar-guided threat missiles, designed to expand current no-escape zones by a factor are also being fielded. As well, electro-optical sensors, immune to some of the existing countermeasures, are being fielded. Focusing on the potential threat from high-speed missiles, there are two broad areas that both deserve attention: (1) missiles that can sustain high-speed; and (2) missiles that can engage at high speeds. In the first category, the response benefits from accurate tracking, ability to use electro-optical sensing as well as expanding the threat engagement envelop. In the second case, more dangerous because of the reduced reaction time and the lack of help from earlier tracking, the intercept calculations are becoming more complex. It is important to focus attention on the complete kill chain as well as the contribution of new and evolving technological capabilities that can respond to such threats. Recent demonstrations of engagement with very compressed timelines and the increased power available to directed energy systems are two examples of defense science and technology that could contribute to future challenges of aircraft self defense. Department of Energy (DOE) Initiatives Dr. Vance Behr, Deputy Director for Military Systems and Technologies, Integrated Military Systems Center, Sandia National Laboratories Dr. Behr prepared an abstract of his presentation for inclusion in this report; it is incorporated below as Box 3-5. 26

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BOX 3-5 Sandia National Laboratories’ Directed Energy Initiatives Dr. Vance Behr, Deputy Director, Military Systems and Technologies, Sandia National Laboratories This talk presented information on a variety of directed energy initiatives that are underway or were recently conducted at Sandia National Laboratories. The topics were broadly divided into those dealing with Ultra Short Pulse Lasers (USPL), HPM, and supporting technologies. In the area of USPL, a number of topics were reviewed, including defensive applications of USPL, a few results from the recent Military Utility Study completed for HEL-JTO, and the different effects of USPL versus continuous wave or long-pulse lasers in various media. A number of activities were reviewed in HPM application space, including the Sandia pulsed power system contribution to the recent CHAMP JCTD, efforts in electronic battle damage assessment, efforts to model the coupling of high-power transient electrical waveforms into electronics, design efforts for frequency agile and steerable HPM antennas, compact HPM sources, and effects measurement of 8-95 GHz radio frequency illumination of representative unmanned aerial systems flight status and command systems. Research in the area of photoconductive semiconductor switches was also presented because of its potential for use in HPM energy delivery systems. U.S. Missile Defense Agency (MDA) Initiatives Dr. Steve Post, Laser Technology Program Manager, MDA Dr. Post began by reviewing the chronology of the Airborne Laser (ABL) program. He noted that the ABL system was incredibly complex, in part because the chemical-oxygen-iodine laser (COIL) required a lot of safety systems on the aircraft. Among the lessons learned from this demonstration program, he noted that it successfully engaged both solid and liquid boosters representing long-range ballistic missile targets. In his opinion, the ABL laser system would work for area defense. The system was sold as ready for transitioning to an operational capability (“ready for prime time”), but in fact most of the technology subsystems were one-of- a-kind integrations. Next, Dr. Post described MDA’s continuing program in DEW defensive systems, including the Diode Pumped Alkaline Laser System (DPALS) and systems carried on remotely piloted aircraft (RPA), and the Fiber Combining Laser (FCL) program. In response to a question on MDA collaboration with the HEL-JTO, Dr. Post said there were informal synergies across programs, rather than formal collaborations. Lincoln Laboratory Initiatives Dr. Daniel Ripin, Assistant Leader, Laser Technology and Applications Group, MIT Lincoln Laboratory Dr. Ripin described the status of the technology for combined fiber lasers, including advances in beam-combining technologies and quantum cascade lasers. Lincoln Laboratory is 27

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investigating hybrid beam-combining techniques (using both wavelength beam combining and coherent beam combining), which could be used to combine a hundred to a thousand single fiber lasers. Dr. Ripin sees fiber amplifier evolution, as in the DARPA goal to produce a 3 kW single-fiber laser, as a good example of laboratory-industry partnering. The DARPA program is currently achieving 5 kg/kW for the Excalibur laser system mounted on a Reaper RPA. Excalibur uses eight 3-kW fibers in the laser array. Office of Studies and Analyses, Assessments and Lessons Learned, Headquarters U.S. Air Force Directed Energy Implications for Future Force Structure Mr. Jeffrey Saling, Chief, Mission Analyses Division This presentation reviewed recent force structure analyses by the Office of Studies and Analyses, Assessments and Lessons Learned, Headquarters U.S. Air Force, including the 2009 Directed Energy Net Assessment and the 2013 Directed Energy Force Application Study. The purpose of the 2009 assessment was to study in depth the effects of projected adversary directed energy air defenses on U.S. air combat missions. The key question it sought to answer was “How will directed energy challenge or marginalize our advantage in air and space?” The analysis indicated that anticipated Red Force defensive DEW capabilities, including both HPM and HEL systems, could substantially compromise the effectiveness of Blue Force air attacks. From the modeling and simulation of representative scenarios, the conclusion was that a Red Force integrated air defense system infused with DEW defensive anti-air systems poses a significant risk to Blue Force strike mission success, but it was difficult to fully assess the impact on Blue Force systems without additional susceptibility testing to feed into the models. The second part of the briefing reviewed a 2011 presentation that Mr. Saling and Dr. Robie had prepared on Blue Force DEW systems as an enabling concept for future mission scenarios. The DEW concepts that were included in that presentation were long-range air superiority (LRAS) using DEW systems for both offensive counter-air and defensive counter-air roles, a next-generation tactical laser weapon (assuming a 150 kW solid-state laser) for nonkinetic attack with low potential for collateral damage, combat ID using a synthetic aperture LADAR employed as a cued sensor, nonkinetic counter electronics (a CHAMP-like air-launched cruise missile), and a Laser Strike Fighter concept for both offensive (engaging tactical air targets and ground targets) and defensive (counter-SAM and counter air-to-air missile) roles. The third part of the briefing was the 2013 Directed Energy Force Application Study, which ACC had requested. This study included aircraft-based DEW concepts for offensive and defensive counter-air in air mission scenarios run with the Brawler scenario simulation system. The concepts studied included LRAS with a large (1.5 MW) COIL mounted in a wide-body aircraft and a Laser Strike Fighter configured as an F-35 B equipped with a 150 kW solid-state laser. The defensive counter-air scenario with the LRAS concept showed increased Blue Force survivability and increased Red Force attrition compared with the no-LRAS scenario. Similarly, the longer-term Laser Strike Fighter concept showed an increase in Blue Force survivability and an increase in Red Force attrition relative to the same counter-air scenario run with a Joint Strike Fighter without the HEL weapon system. 28

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presentation on the ENDURANCE program [given during the third session] was a good example of a pod-based HEL system that could be carried on a Reaper RPA or other aircraft. Another counter-comment was that, during a simulation-based analysis of alternative self-protect systems for the F-15, a HEL system was assessed to be more effective than a gun system. Tuesday, March 19, 2013 Session 2, Day 2: Welcome and Recap of Day 1 Gen Ronald E. Keys (USAF, Ret.), Session Chair Gen Keys welcomed the participants to the second day of Session 2 of the Workshop on Assessment of Directed Energy Research and Development for U.S. Air Force Applications. He noted the presentations that had been given on Day 1 and summarized highlights of the participants’ discussions. Returning to the issue raised in the Day 1 wrap-up discussion of what might be the key DEW applications—and particularly HEL weapons—for nearer-term Air Force applications, a participant noted that aircraft-carried HEL systems for antisensor and combat ID applications had not been discussed yet in Sessions 1 and 2. The chair agreed with the point and added that the participants also needed to think about counter surface-to-air-missile (counter-SAM) applications, applications to counter surface-to-air aiming subsystems and counter-optics, and counter-sensor applications generally. For those applications, he explained, the energy and power for effectiveness does not need to be as high as for vehicle-skin defeat mechanisms. A HEL in the 25-30 kW range might suffice, he said, but adequate stand-off range would be a critical requirement. In the third-session review of Session 2 highlights, several participants agreed with the chair’s comment that the counter-sensor and combat ID applications for HEL are good missions for the Air Force. One participant noted that the range for such “lower-power” HEL systems might be even lower, perhaps down to 10 kW. Another comment on the last statement was that weather (e.g., clouds) remains an issue [in addition to stand-off range], and a third participant suggested that critical requirements would be “adequate range, tracking, and pointing.” Boeing DEW Initiatives: CHAMP JCTD Overview and Follow-on Next Steps Mr. Keith Coleman, CHAMP Program Manager, Phantom Works, Boeing Mr. Coleman prepared an abstract of his presentation for inclusion in this report; it is incorporated below as Box 3-6. 35

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BOX 3-6 CHAMP JCTD Overview and Follow-on Next Steps Mr. Keith Coleman, CHAMP Program Manager, Phantom Works, Boeing The CHAMP (Counter-electronics HPM Advanced Missile Project) program designed, developed, and flight-tested a missile-deployed HPM weapon system. CHAMP allows warfighters to target the electronic systems of an adversary and disable their ability to function. By using an HPM warhead, CHAMP provides a highly effective but nonlethal counter-electronics capability to minimize or eliminate target collateral damage. The CHAMP team integrated a spectrum of complex systems (flight controls, power distribution, HPM source, targeting systems, etc.) creating solutions in a number of flight control and materials fields on their way to a successful flight test on October 16, 2012, at an Air Force flight test range. Problems that were overcome included pulse power generation, voltage isolation, electromagnetic protection of vulnerable missile flight systems (prevention of self-kill), precise targeting, weapon pointing and triggering techniques, microwave beam propagation to target, prediction and verification of microwave weapons effect on targeted electronics, and development of the concept of operations and operational analysis of a new class of missile. The CHAMP team, which included members from the Air Force, Boeing, Sandia National Laboratories, and Raytheon, developed this engagement capability with the potential to minimize reconstruction requirements post-conflict. The weapons system provides the capability for multiple, nonlethal, pinpoint airborne strikes against targets that were previously denied due to proximity to, or co-location with, noncombatants. A rapid acquisition program was proposed and is available to provide assets for warfighter use in the near term. Raytheon DEW Initiatives: CHAMP Payload and Effects Testing Dr. Peter Duselis, Raytheon Company Dr. Duselis began by noting that the CHAMP payload in the 2012 flight test was at TRL 7. The current HPM source used in CHAMP, ACES, requires a vacuum pump to maintain the system, and the vacuum condition in the system is the critical factor for system shelf life. It will hold a vacuum for a year, then requires 24 hours to pump down to the working pressure. Dr. Duselis also described the software modification that would allow CHAMP to used the onboard power of the B-52 carrying it before release. He reviewed the flight test results, which Mr. Bruner and Mr. Coleman had also covered, but provided more detail on the level of effects on the target electronic systems. Dr. Duselis then reviewed the major components of the proposed CHAMP payload improvements and explained their value. Overall, the proposed upgrades would provide higher effective radiated power, eliminate or simplify subsystems, and multiple pulses on target. For the proposed two-pulse option, pulses could be as close together as 10 ms. HPM effects testing is necessary to answer questions about HPM effectiveness against potential targets. In June 2011, Raytheon and AFRL entered into a cooperative research and 36

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development agreement (CRADA) to enhance the existing database for HPM effects. Dr. Duselis presented details of the effects testing done at White Sands Missile Range, including the effects of the ACES-derived HPM beam on various targets of interest for Air Force counter-electronics attack. The workshop participants and Dr. Duselis discussed potential uses and CONOPS for a CHAMP-like counter-electronics capability. General Atomics DEW Initiatives Dr. Chris Pehrson, General Atomics Dr. Pehrson presented the briefing for Dr. Michael Perry, Vice President, Laser and Electro-optics, General Atomics, who had a last-minute schedule conflict. The presentation began with an overview of the emergence of electrical power systems suitable for DEW systems on jet-powered armed reconnaissance RPAs such as Predator and Avenger. The second topic was the integration of optical radar (LIDAR) into widely deployed EO/IR turrets. The third topic was on the emergence of tactical laser weapons in the DARPA HELLADS program, including the second-generation HEL Avenger system and the third-generation Laser Weapon Systems Module (LWSM). Dr. Pehrson described the evolution of Predator/Avenger RPAs and characteristics of the latest generation. He then presented characteristics of the Spi-3D LIDAR and its use of three- dimensional (3D) voxels to get precise ranging and targeting data over the entire field of view of the LIDAR, enabling real-time precsion-targeting of multiple targets. This capability can be installed in existing Predator airframes with only minor modification to the sensor ball. On electric lasers for tactical laser weapon applications, Dr. Pehrson noted both advantages (ultra- precise effects, deep magazine, low cost per shot) and constraints (aimpoint must be maintained on moving target for 3-4 seconds, not an all-weather capability) of tactical laser weapons. He contrasted the SWaP requirements of the new distributed-gain electric lasers with the SWaP requirements of the Airborne Tactical Laser. This new electrical laser would potentially fit entirely within the internal bay of an Avenger RPA and has an output of 100 kW. The recharge time is 2-4 minutes versus more than an hour for the ATL, and the magazine depth is unlimited. Next, Dr. Pehrson discussed the DARPA High Energy Liquid Laser Area Defense System (HELLADS), which aims to take a distributed gain solid-state tactical laser system from concept to weapon system demonstration with a 150 kW output power objective. A HELLADS Demonstrator Laser Weapon System (DLWS) with 150 kW output is now complete and is scheduled to be delivered to White Sands Missile Range on June 30, 2013. RELI is a second-generation HELLADS that is now undergoing laser performance validation. First light for the laser head, Dr. Pehrson reported, was on March 19, 2013. Its size and weight are small enough to enable it to be carried under a Predator C Avenger RPA (the HEL Avenger concept), and its output power is about 100 kW. Unit cost of the HEL Avenger laser system will be about $20 million to $22 million. Dr. Pehrson presented information on modeling and analysis tools that will be used to model efficacy of the RELI system, when mounted on an airborne platform, against a range of potential targets. The next generation beyond the RELI unit cell in the HEL Avenger system will be a 150 kW HELLADS DLWS laser, 37

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incorporated in the Airborne LWSM. The long-term objective for Airborne LWSM is to successfully attack and take out an integrated air defense system. Navy Initiatives (China Lake) Mr. Tom Glover, Head, Emergent Weapon Systems, Directed Energy Weapons, Naval Air Systems Command (NAVAIR) Mr. Glover gave his briefing by telephone, with briefing slides displayed at the workshop meeting room. He reviewed the NAVAIR roadmap for HEL weapons R&D and transition. The roadmap projects reductions over time in the SWaP for different tactical platforms. A key issue for reducing SWaP is the ruggedization needed so that systems can withstand carrier-based take-off and landing. Multiple departments within NAVAIR are involved in work on integrated laser systems for different Navy platforms. Mr. Glover also reviewed the NAVAIR roadmap for HPM weapons R&D. For the Navy, HPM is a niche application, compared with HEL weapon systems, which are seen as being used on many platforms for different applications. Turning to countermeasures development, Mr. Glover discussed anticipated near-, mid-, and far-term HEL and HPM weapon systems that potential adversaries may have. The NAVAIR countermeasures group has developed a “laser technology landscape,” which Mr. Glover presented. He discussed laser threats to Navy sensors and NAVAIR’s plans to work with AFRL on sensor protection. He also discussed hardening required to defend electronics against an HPM threat environment, including NAVAIR plans for live fire test and evaluation for survivability against HPM attack. He closed the presentation with a summary of joint Air Force/NAVAIR activities. Technological Assessment of Foreign Directed Energy Mr. Michael H. Bernard, Senior Intelligence Analyst, AFRL This assessment covered both radio frequency weapons (RFW) such as HPM and HEL weapons. Mr. Bernard described what is known about the technical status of work in specific foreign R&D institutes on both RFW and HEL weapons. Discussion of Day 2 Presentations and Plan for Session 3 Gen Ronald E. Keys (USAF, Ret.), Session Chair The following high-level points were suggested by one or more of the Session 3 participants who were present for this final discussion. Elements of these points have been incorporated in the thematic overview in Chapter 2. • Many of these participants who spoke agreed that some DEW technologies are ready for tactical application, in the sense that some capability does work and could have operational value. The Army and Navy have demonstrated prototypes. What is missing is what some described as a capabilities-based assessment and others described as “an operational need backed up by an Analysis of Alternatives.” They agreed that the focus of this assessment, however structured, should be to 38

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determine how DEW capability could complement, expand, or replace kinetic weapon alternatives. — Several emphasized that this assessment, however done, should focus on what can be done now and what can move now from demonstration to prototypes. (See Theme 3.1 for more on this point.) — Many participants thought the compelling missions for DEW need to be identified. One suggested that an important area to consider is the potential integration of kinetic weapons and DEWs—for example, in a campaign-level analysis of how they would work together. A specific example suggested by a participant was target marking, with a DEW to prepare and mark a target for a follow-up kinetic attack (this was not intended to mean just a laser-designation application). Another participant mentioned counter-sensor and combat ID roles as mission area where DEW and kinetic weapons could work together. • With respect to HPM weapons, many of these participants thought it important to go forward with CHAMP acquisition. — For example, one participant suggested taking advantage of the interest in CHAMP from at least one COCOM—get an initial capability out there and then look at how to improve it. — Several participants who favored going forward on CHAMP did not favor doing all of the proposed upgrades as part of an initial buy. One of them explained that the upgrades, although valuable, introduced technical and programmatic/schedule risks that were best avoided at this point. A block-buy evolution of capability was suggested by one participant. • There was considerable discussion, with a range of views expressed, about the near- term prospects for laser DEW capabilities. The views expressed on this topic are represented in the Chapter 2 discussion of Themes 1.2, 2, 3.1, 3.2, 3.3, and 3.4. • With respect to Blue Force defense against Red Force DEW systems, a number of these participants suggested that an assessment (again, a capabilities-based assessment or something like an Analysis of Alternatives) was needed of counter- DEW options. What is (are) the most effective way(s) to counter Red Force DE capability, either offensive or defensive? — An important issue for counter-DEW, several agreed, is the relative cost of alternatives, including kinetic as well as nonkinetic (DEW) alternatives. As one participant expressed this issue, “What other capability would be worth giving up to get a DEW capability for counter-DEW?” — In the context of Blue Force airborne DEW weapons to counter Red Force defensive, ground-based DEW weapons, several comments suggested that an open question is whether airborne DEW weapons would be successful in “jousting” with the larger, more powerful Red Force systems. Other comments suggested that countering Red Force defensive DEW systems might be best done by CONOPS that combined DEW and kinetic weapon capabilities. 39

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SESSION 3 APRIL 24-25, 2013 WASHINGTON D.C. Wednesday, April 24, 2013 For this session, the workshop planning committee developed guidance specific to individual invited presenters on questions to be answered or topics to be addressed. The guidance given for the presentations from the Air Force Air-Sea Battle Office, the Army, and DARPA was specific to each of those topics and is included in the synopses below. The three presenters from industry (Lockheed Martin, Northrop Grumman, and Boeing) were given the same guidance: Describe fairly near-term (5 years or less) laser DEW concepts that address Air Force missions. Include effectiveness for Air Force missions and CONOPS thoughts. To this end, the workshop participants do not need details about the technology, per se. These missions could involve low- to-medium power lasers (e.g., 10 or 10s of kilowatt power levels). NOTE: HEL-JTO, MDA, AFRL, MIT/LL, DARPA HELLADS, Army SMDC, Navy ONR, ACC, and General Atomics have already provided briefings. The workshop participants would prefer that the briefing not be proprietary since a summary of the briefing will go into a National Academy document. The presentation can be up to the Secret level. Welcome and Introductions Gen Ronald E. Keys (USAF, Ret.), Session Chair Gen Keys opened the meeting and asked the participants to introduce themselves. He then proceeded directly to the first topic, which was to discuss and comment on the rapporteur’s draft themes and major points from the first two sessions. Discussion of Themes and Points from Sessions 1 and 2 Dr. Robert Katt, Rapporteur As he did at the beginning of Session 2, Dr. Katt reviewed with the Session 3 participants a draft of highlights (key themes and points made by individual participants) from the previous two sessions. The participants’ comments were captured for incorporation into the final version of themes presented in Chapter 2 of this workshop report. Air-Sea Battle Concept of Operations Col Jordan Thomas, HAF/A5X The specific guidance sent to Col Thomas was to address the following questions: 1. Which service has the lead for protecting such fixed bases as Guam? 2. Has this [protection of fixed bases] been coordinated with the Army for their base protection [mission]? 40

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3. Are directed energy weapons (DEW) being considered in the trade space for that protection? 4. What Air-Sea Battle operational needs could potentially be met by DEW? 5. Have any threats been identified by [the Air-Sea Battle organization] that suggest potential Blue Force DEW applications? Col Thomas noted that Air-Sea Battle is not new for either the Air Force or Joint forces, but it has not been updated since about 2000. With respect to question 1, he said that, according to JP-3-10 doctrine, the lead service for protecting a fixed base depends on the command structure set up by the responsible COCOM. There is no single executive agent for area air defense coordination. He then described some of the current planning for defense of Guam. On question 2, Col Thomas said that the Army and Navy have their own DEW programs. There is no coordination between them and the Air Force. With respect to question 3, Col Thomas said that DEW is not included in the defensive solutions being considered by the Air-Sea Battle Office. He agreed that it could be a capability of interest. Base defense is the number-2 priority, and the Air-Sea Battle Office sees a need for a capabilities-based assessment for base defense. But to his knowledge, neither the Air Force nor the Joint Staff have done or considered such an assessment that includes DEW. In response to a later question, he said that DEW capabilities are not included in Air Force and Joint wargaming. In response to question 4, Col Thomas said that the principal long-term threat for his office is A2AD (anti-access/area denial) by an adversary. The trend toward higher precision in Red Force offensive systems means that A2AD is becoming a concern with respect to an increasing array of potential adversaries. In response to a question, he said that nearer-term threats, such as having to operate in Southwest Asia or South Asia, are also a concern. Col Thomas also highlighted the key principles that the Air-Sea Battle office is applying to planning for various scenarios. He responded to participants’ questions about how specific DEW capabilities might be useful. Results of Army DEW Analysis of Alternatives (AoA) Dr. Kip Kendrick, Chief, Directed Energy Division, U.S. Army Space and Missile Defense Command, Army Forces Strategic Command For this briefing, Dr. Kendrick was sent the following guidance from the workshop planning committee: 1. Describe the AoA that was done for the counter rocket, artillery, and mortar base defense mission and the outcome of the AoA. 2. Why was the final decision for the go-ahead not the alternative that came out on top for the AoA? 3. Summarize what the AoA found were the advantages of DEW over alternative kinetic solutions. Dr. Kendrick started by providing more background on the IFPC II AoA than he had given in his presentation to Session 1, including the motivation and the specific scenario and 41

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parameters that had to be addressed. One requirement was to provide complete life-cycle cost estimates for two battalions of each alternative capability. The DEW options did well on cost because they did not have to replace bullets or missiles. With respect to the ratio of threat kills to the total number of threat targets presented, the 100 kW HEL system had the highest score, followed by the EAPS missile option and the 50 kW HEL option. For the HEL systems, the beam control system and laser head were identified as having moderate technical risk, given their developmental status. Also, the DEW options were viewed as unsuccessful in fog, rain, and sandstorms. Since the AoA, the Army has expressed increased interest in cruise missile defense as part of defending a FOB. To Dr. Kendrick’s knowledge, HEL systems were not included in the Army’s analysis of cruise missile defense alternatives, although he offered to provide data to them. In response to participants’ questions about his sense of the Army leadership’s resistance to HEL for base defense, Dr. Kendrick recounted the story of how the Army refused to consider main battle tanks in World War I. The Army was not interested until after Winston Churchill set up the Land Ship Commission and successfully deployed British tanks in trench warfare. He sees DEW systems as in an analogous position, with no specific formal requirement and no acquisition program. Dr. Kendrick is working on requirements for a couple of DEW platoons for the Army. To get to an advanced prototype, he needs an advanced beam control system. He is looking for funding to do a full-up prototype system for a Joint prototype demonstration with Air Force and Navy support, but not a JCTD. DARPA Airborne DEW Initiatives Dr. Joseph Mangano, Program Manager, Advanced Lithograph Program, Microsystems Technology Office, DARPA The specific guidance sent to Dr. Mangano for this briefing was as follows: 1. Describe your laser program, including its progress to date and its future plans, as well as its relevance to the Air Force. 2. Provide examples of Air Force operational needs that could possibly be met by low- and/or medium-power lasers. Dr. Mangano’s presentation focused on the DARPA Endurance and Flash programs, both of which use fiber laser arrays. The technological objective is to achieve “ultra-low SWaP” at 2 kg/kW specific power and a size of 1 m3 per 100 kW. The SWaP is critical for both these programs, he said, and the integrated system must be conformal to aircraft platform constraints. As applications of interest, he mentioned aircraft self-defense and mid-course ballistic missile defense. In both technologies, the light reflected from the target (the return) is used to tune the combined multiple beams from 3-kW laser fibers. The individual 3 kW fibers operate at 35 percent wall-plug efficiency. This works well enough that the beam at the target is close to the diffraction-limited spot size. Although Dr. Mangano said the limits of scalability for this beam- combining approach are not clear, he can do a hundred or more fibers together and believes the technology is scalable to a 1 MW output beam. 42

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The Endurance program is aimed at defeating EO/IR guided surface-to-air missiles that threaten airborne platforms at altitudes up to 50,000 feet. Dr. Mangano described what he sees as the capabilities of current state-of-practice Red Force surface-to-air missiles, as well as some of the emerging threat capabilities, and he discussed how an Endurance system would likely perform against these threats. The program is planning to use a HEL pod that is small and light enough to fly on legacy aircraft as well as advanced next-generation aircraft. The Flash program is focused on defeating existing EO/IR guided air-to-air missiles, as well as surface-to-air missiles, with a beam power of up to 300 kW. The Excalibur program was the predecessor of Flash. Dr. Mangano described the key technologies and the program roadmap to go from the current Excalibur program to Flash capability that includes a 30-shot magazine. In closing, Dr. Mangano gave the current milestones for the Endurance and Flash programs between FY 2014 and FY 2017. Lockheed Martin HEL Efforts Mr. Thomas Burris, Lead Systems Engineer, Directed Energy Program, Lockheed Martin Mr. Burris prepared an abstract of his presentation for inclusion in this report; it is incorporated below as Box 3-7. Northrop Grumman Laser Efforts Mr. Kenton Ho, Director, Laser Products Directed Energy, Northrop Grumman Mr. Ho began with an overview of Northrop Grumman’s current (2013) HEL programs. Northrop Grumman is now working with solid-state lasers in the 100 kW class. He described the BOX 3-7 Lockheed Martin HEL Efforts Mr. Thomas Burris, Lead Systems Engineer, Directed Energy Program, Lockheed Martin Laser weapons can create a wide range of effects that span the find, fix, track, target, engage, assess (F2T2EA) targeting chain. There are advantages in time (proactive effects, counter salvos), favorable cost-exchange ratios, precision, reduced collateral damage potential, and magazine depth (e.g., increase mission duration). Lockheed Martin has performed numerous airborne operations analyses and aircraft integration studies that have led to the following conclusions: (1) directed-energy weapons will not replace kinetic capabilities, but rather directed-energy and kinetic weapons are complementary and synergistic; (2) high-energy laser weapons can help fill numerous capability gaps spanning the breadth of offensive and defensive missions; and (3) multiple, compelling applications have emerged as opposed to a single “killer application.” A final point worth noting is that a first-generation laser weapon needs to provide sufficient output power and beam quality to enable operational capabilities that are commensurate with the high cost of the laser weapon system and aircraft integration. 43

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Maritime Laser Demonstration, which involved engaging small-boat threat scenarios out to 6,000 yards. He also described the attack performance of a 10 kW HEL pod mounted on a RPA. The presentation included an overview of Northrop Grumman studies of HEL weapon systems on tactical aircraft for defense against surface-to-air missiles in an A2AD scenario. HEL systems from 25 kW to 150 kW were considered and were evaluated against low-observability alternatives. Mr. Ho emphasized the increase in aircraft “autonomy” and flexibility provided by a multiuse tactical HEL weapon system. In closing Mr. Ho said that ACC needs to give industry a clear requirement, then let industry work out the best, most affordable way to meet it. Boeing Airborne DEW Systems Dr. Harold Schall, Boeing; Mr. Michael Black, Boeing Dr. Schall prepared an abstract of his presentation for inclusion in this report; it is incorporated below as Box 3-8. General Discussion on Day 1 Presentations Gen Ronald E. Keys (USAF, Ret.), Session Chair Gen Keys asked the participants for comments on the Day 1 presentations. The participants’ comments have been selectively incorporated in the rapporteur’s overview of workshop themes (see Chapter 2). BOX 3-8 Boeing Airborne DEW Systems Dr. Harold Schall, Boeing; Mr. Michael Black, Boeing Boeing has made significant progress over the past decade maturing HEL system technologies and demonstrating the capabilities of integrated HEL systems. Demonstrations such as the Airborne Laser’s lethal shootdown of a boosting missile and the Airborne Tactical Laser’s precision strike engagements against static and dynamic targets have clearly shown the unique capabilities offered by a directed energy weapon. Based on the current state of HEL system technologies, Boeing has identified three Air Force mission areas that it believes can be addressed in the fairly near term by low- to medium-power lasers. These mission are (1) Aircraft Self Protection from Advanced EO Threats, (2) Precision Air-to-Ground and Air-to-Air Engagements and (3) Long Range Detection and Engagement from Airborne Platforms. The mission space addressable in the near term spans a wide space and multiple platforms. This presentation describes the directed-energy concepts and capabilities that address these Air Force mission areas. 44

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BOX 3-9 CHAMP Advocacy Brief Dr. David Robie, Office of the Chief Scientist, ACC The Counter Electronics High Power Microwave Advanced Mission Program (CHAMP) Joint Capabilities Technical Demonstration just completed a 3-year, $70 million development effort with outstanding results. The Air Force would like to leverage this positive outcome and investment to provide the warfighter with game-changing capabilities. This presentation discusses the requirements for the capability, the results of the operational utility assessment, a discussion of the survivability of the weapon and an evaluation of countermeasures to the weapon’s effects. It concludes with a presentation of courses of action to field this asymmetric and disruptive capability. A Retrospective Look at the Northrop Grumman Laser Weapon System Initiative (LWSI) Dr. Thomas Romesser, Independent Consultant, Member of the Workshop Planning Committee To provide the workshop with a historical perspective on the degree to which technology HEL status forecasts and envisioned DEW applications have (or have not) changed in the past decade, Dr. Romesser presented and discussed a PowerPoint briefing he had prepared on the Northrop Grumman Laser Weapon System Initiative (LWSI) in 2003. ACC Draft Briefing on CHAMP Dr. David Robie, Office of the Chief Scientist, ACC Dr. Robie prepared an abstract of his presentation for inclusion in this report; it is incorporated below as Box 3-9. Discussion of Potential Workshop Themes and Key Points Gen Ronald E. Keys (USAF, Ret.), Session Chair Gen Keys asked the participants for their general reflections on this session and the workshop as a whole (for those who had attended other sessions). He also asked for any additional comments they had on the draft themes and major points that had been presented and discussed on Day 1 of this session. The participants’ comments have been selectively incorporated in the rapporteur’s overview of workshop themes (see Chapter 2). 45