America’s military test- and training-range infrastructure is positioned squarely at a crossroads. Challenged by the prospect of a decade of defense-budget sequestration impacts and with increasing modernization and sustainment costs visible on the horizon, affordability concerns will continue to constrain essential modernization plans. The critical requirement to keep pace with advanced-threat technologies, and the associated need to continuously adapt Fleet tactics, techniques, and procedures (TTPs), will further pressurize the prioritization of those range capabilities in greatest need of modernization.
And perhaps one of the most insidious factors to be considered is the need to contend with the proliferation of encroachment concerns from such diverse sources as commercial and residential development, electromagnetic-spectrum interference, cyber effects, operating airspace conflicts—and wind-turbine interference.
The issue of wind-turbine interference with naval test- and training-range operations has played out with increasing regularity over the last several years as wind-farm footprints have expanded in response to the nation’s focus on alternative energy. This is attributable in part to the proximity of attractive wind energy–generation locations to many range facilities critical to naval aviation. Among the numerous sites impacted by wind farms have been the Boardman Naval Weapons Systems Training Facility in Oregon, the Naval Air Warfare Center Weapons Division in California, Naval Air Station (NAS) Kingsville in Texas, the Dare County Bombing Range in North Carolina, and the Naval Air Warfare Center Aircraft Division (NAWCAD) in Maryland.
Conflicting Causes, Clashing Coalitions
The wind-farm encroachment threat that has perhaps garnered the most recent attention is associated with plans to construct a new facility along the Chesapeake Bay on Maryland’s Eastern Shore southeast of NAS Patuxent River. The ensuing debate has pitted strident advocates of alternative energy and regional economic development against an equally passionate coalition of defense advocates concerned about the effects of wind-turbine interference on the highly specialized radar testing conducted by NAWCAD on the Atlantic Test Range. Because of the levels to which this current dispute has been raised, its ultimate resolution will likely establish an important precedent that could portend the outcome of future encroachment settlements.
Before examining the specific issues in this debate—and the national-security issues at stake—it would be worthwhile to consider the operational backdrop against which the current deliberations are playing out. Consider for a moment that the passage of nearly a quarter century has arguably pushed into the recesses the extraordinary warfighting spectacle of Operation Desert Storm. In the very early hours of 17 January 1991, an unprecedented display of rapid dominance unfolded over the Iraqi landscape. The initial joint air campaign included wave after wave of U.S. and coalition assets conducting strikes against targets inside both Iraq and Kuwait, including employment of naval aircraft and the stealthy U.S. Air Force F-117A Nighthawk. U.S. and allied forces, and particularly naval forces, launched a barrage of more than 100 Tomahawk land-attack missiles (TLAMs) from U.S. Navy cruisers, destroyers, and battleships.
F-117A missions were conducted deep into Iraq against hardened command-and-control bunkers, aircraft shelters, and production and storage facilities for nuclear, biological, and chemical weapons, as well as other highly defended military and political targets. Flying into intense anti-aircraft artillery fire and surface-to-air missile defenses, the F-117As flew 1,300 combat sorties and scored more than 1,600 direct hits in the initial 43-day campaign without experiencing a single loss or suffering material damage.1 Many Americans will recall listening to the evening news correspondents reporting from Baghdad that “I hear bombs but I don’t see any planes.” They were to find out later that the reason was that the systems designated to strike critical infrastructure targets inside Baghdad were low-observable F-117As and TLAM assets. As full partners in the campaign, Navy and Marine Corps aircrews operating from carriers, large-deck amphibious ships, and shore-based air stations struck Iraqi targets up to 700 miles from their takeoff locations in the Persian Gulf, Red Sea, and Arabian Peninsula.2
This exceptional military achievement in the opening days of Desert Storm included a dramatic display of American sea control and maritime superiority—overwhelming multidimensional firepower—that had not been previously witnessed on the world stage. The successes achieved in this prodigious demonstration of force heralded the arrival of a new era of military capability, one made possible by a generation of investment in technologies such as smart weapons, unmanned systems and, importantly, stealth capability. This latter category, critical to military successes such as Desert Storm, will remain one in which the U.S. government, academic institutions, and private industry must remain fully invested to pace the evolving threat. The United States must be mindful of the likelihood that future theaters of operation could include anti-access/area-denial conditions involving the presence of long-range antiship cruise missiles, a new generation of cyber- and electronic-warfare threats, and emerging maritime nations with potential to extend their reach to global dimensions.
The High Value of Low-Observable Tech
Low-observable technologies will undoubtedly continue to be one of the most heavily employed tools used by our tactical-aviation forces. The threat level presented by Iraqi integrated air defenses in Desert Storm, or in other more recent conflicts, is not representative of that which potential adversaries are capable of presenting in the future. And the success of previous and current generations of deployed U.S. low-observable platforms against these defenses is not necessarily a measure of our performance against advanced integrated air-defense systems likely to be encountered in future conflicts. It is broadly recognized that while low-observable design features will never be the sole determinant of tactical aircraft susceptibility to detection, these characteristics will remain a critical element in overall platform survivability and mission success.
Many billions of dollars have been invested in the development of stealth technologies during the past 75 years, dating back to the years leading up to World War II. Department of Defense science and technology investments have been instrumental over the decades in understanding the physics of stealth, and these investments have directly led to today’s arsenal of the world’s most combat-effective low-observable aircraft.
Airborne radar cross-section (RCS) testing has been critical to ensuring that the stealth characteristics of our tactical aircraft inventory are actually realized. Accurate measurements depend on using sophisticated radar facilities and associated evaluation infrastructure. Indeed, these complex-signature test-and-evaluation (T&E) facilities have been indispensable for decades in evaluating RCS, jammer-to-signal ratio, and chaff effectivity for generations of fixed- and rotary-winged aircraft, unmanned aerial systems, towed targets, and decoys. The Naval Air Systems Command’s (NAVAIR’s) Patuxent River site is the principal location of this complex and capital-intensive testing for the U.S. Navy, Marine Corps, joint services, and international partners.
An Impending Threat to Aviation Ops
Much of the historical stealth-technology development activity has necessarily gone on in the shadows of government, academic, and private laboratories, in various private industrial facilities, and at DOD warfare centers. This is appropriate given the classification and associated level of sensitivity of the technologies. However, occasionally there are issues of regional interest and national-security focus that force these bodies of work into the public square. One such issue has emerged with the aforementioned proliferation of wind-turbine power-generation facilities throughout the country. With this expansion has come the widespread threat of turbine blade–induced interference with Federal Aviation Administration (FAA) air-surveillance radars, terminal-approach radars, military training–range radars, and test-range radar systems, including those used to evaluate military aircraft survivability.
Wind turbine infrastructure-development projects hold promise in creating a renewable energy alternative to fossil-fueled power generation, and are attractive as job creators to fuel economies in regions that, in some cases, are still laboring under the strains of economic recession. During the past 15 years, the United States has seen an increase in wind-generation capacity from 4 gigawatts (GW) to over 60 GW. In fact, wind energy growth has approximated 30 percent per year for the past five years, and there are projections that by 2030 this capacity could grow to as much as 305 GW, constituting 20 percent of the nation’s electricity.3
At the end of 2013, there were more than 45,000 utility-scale wind turbines and 560 wind-related manufacturing facilities operating throughout the United States. Additionally, commercial utility-scale wind-turbine operations have been established in 39 states.4
Continued expansion of this industry has raised awareness that while the contributions of wind turbines to green energy generation appear promising, unresolved risks remain surrounding the detrimental impacts from operation of these facilities on critical FAA and military radar systems. These systems emit radio waves in the direction of airborne targets and receive return signals from the energy reflected from the surface of the contacts. The signals are processed and converted into information that is used to identify the range, altitude, direction, and speed of nearby objects. Radars determine the presence of moving objects by evaluating the Doppler shift of the target’s echo. Interference from wind turbines occurs when the rotating blades produce echoes with the same Doppler frequency offset as those of target aircraft, such that the wind-turbine returns look like an aircraft to the radar. This can result in the presentation of numerous false tracks, high levels of clutter, dropping of actual live aircraft tracks, and offset of actual tracks to false positions on the radar display.5
There have been no serious safety incidents to date related to wind-turbine interference with military-surveillance radars, and the majority of proposed wind-turbine projects present no concern to the DOD. Because of the risks to the FAA’s ability to continue to safely track the nation’s air traffic in regions in proximity to wind farms, ongoing research is being conducted to identify procedures and technologies to mitigate FAA and military air-traffic control (ATC) radar-frequency interference. These approaches have resulted in only limited success to date, with most requiring further technology development and considerable additional funding.6 Due to these technical hurdles, many authorities believe that proper siting of turbines may be the only effective means of interference mitigation.7
The DOD Siting Clearinghouse was established in 2010 to evaluate the impact on test, training, and operational missions from those energy projects in proximity to military facilities that present a potential encroachment threat. Organized under the Deputy Under Secretary for Installations and Environment, the clearinghouse is responsible for coordinating the assessment of commercial energy projects across each of the services. The Navy evaluated 2,075 proposed energy-related projects in 2013, including wind-farm projects, and determined that 96 percent of them would have little or no impact on its operations. Only eight projects were found to have an adverse impact on the Navy’s mission such that formal mitigation activities would be required.8
Aircraft Signature Testing
As much of a concern that the proliferation of wind farms poses to U.S. commercial and military ATC operations, there exists a commensurate concern surrounding the unique and highly specialized radar systems associated with dynamic RCS testing of military aircraft and weapon systems. Critical to maintaining the superiority of stealth technology as a warfighting advantage is the unique infrastructure that has been developed over the decades to measure its performance in open-air range testing within the Atlantic Test Ranges (ATR), a 3,000-square-mile expanse extending over the Chesapeake Bay and Maryland’s Eastern Shore.
The single most critical of these radar systems is known as the Advanced Dynamic Aircraft Measurement System (ADAMS). The only system of its kind in the world, it has operated for more than 40 years from its location at NAS Patuxent River. The highly integrated ADAMS facilities provide telemetry, tracking data, range control, airborne instrumentation, and RCS data acquisition, all in a centralized workstation environment that provides analysis and display of the ground-to-air RCS measurements in real time. ADAMS data products include depictions of amplitude, Doppler, and downrange and inverse synthetic-aperture radar outputs.
To ensure mission success and aircrew survivability, it is critical to measure and understand the interaction between an airborne platform and the electromagnetic energy that may impinge upon it. This measurement information, first and foremost, provides a means to assess the platform’s survivability in a threat environment. Signature data is analyzed during vehicle development and modernization to provide diagnostic information needed to optimize its performance characteristics and ensure specification compliance. As a platform matures and its configuration changes throughout its life cycle, it is important to quantitatively reassess its radar reflectivity. RCS data also is considered essential for electronic-countermeasures development, to provide information for noncooperative-target recognition, and to support the development of TTPs.
Highly trained and experienced engineers, scientists, and analysts are responsible for evaluating the data. “I want to know how I’m presenting myself nose-on, what I look like broadside, what I look like going away from you,” NAVAIR Test Manager Larry Miller said. “We’re trying to measure the signature of the aircraft and then determine what kinds of countermeasures and tactics—dropping chaff, jamming enemy surveillance, flying evasively—are required to protect that aircraft in a hostile situation.”9
Key to the ability of ADAMS to perform these Fleet mission-essential functions is maintaining electromagnetic interference–free environmental conditions that allow high-fidelity measurements critical to evaluating aircraft stealth performance. Failure to do so will ultimately impair mission performance of the naval aviation platform inventory, diminish the multigenerational investment made in low-observable technology, and erode the continued evolution of Fleet TTP development.
Signature Measurement’s Uncertain Future
The greatest threat in several decades to the unimpeded operation of the ADAMS facility is the growing encroachment concern posed by the wind-turbine farm project planned for construction along the Chesapeake Bay on Maryland’s Eastern Shore, approximately 30 miles from the ADAMS installation at NAS Patuxent River. The project has been in the planning stages for four years and is a commercial venture sponsored by Texas-based Pioneer Green Energy. Current plans for the project include installation of an initial 25 wind turbines near the town of Westover in Somerset County. Located adjacent to a main power-transmission line, the wind turbines would be placed about 1,000 feet apart. Project plans include a tower-design height of 464 feet, with 187 foot-long blades capable of spinning as fast as 200 mph. Adam Cohen, vice president of development for Pioneer Green, said, “In a rural wind speed–type site, you need to be capturing some of those higher wind speeds. We can’t be shorter, because then the project loses its economics.”10
A mission-compatibility evaluation of the Pioneer Green project was initiated by the DOD Siting Clearinghouse, and the Navy-level assessment is complete, with a determination that a curtailment agreement to limit turbine operations during ADAMS testing would satisfactorily mitigate risk to mission impact. However, on 30 October 2014 Deputy Secretary of Defense Robert Work forwarded a letter to Secretary of Transportation Anthony Foxx objecting to the project because of its potential to significantly impair or degrade DOD research, development, test, and evaluation (RDT&E) operations, and to place military forces at greater risk when they go in harm’s way.11 A disapproval decision must involve a determination that the project presents a demonstrated threat to national security, which is defined to include significant impact to RDT&E activities.
NAVAIR commissioned the Massachusetts Institute of Technology Lincoln Laboratory (MIT LL) in early 2012 to conduct an independent assessment of wind-turbine impact on ADAMS radar performance. This study found that the ADAMS system will be significantly affected by wind turbines within its line-of-sight (LOS) and that the mission could not be accomplished with the presence of wind turbines in the main lobe of the radar beam. However, it was determined that there might exist several mitigation options that would permit continued operation if the turbine locations were repositioned in the side lobes of ADAMS.
The report concluded that preservation of the entire current ADAMS field of view may be unrealistic given current turbine siting plans, but that impact-mitigation efforts can preserve the mission with a smaller ADAMS operating footprint. For this reason, the study recommended that an exclusion be placed on turbine siting within the radar’s LOS until mitigation options were available. Among the mitigation technologies recommended for further study were system relocation, interference-blockage fences, test-planning changes, modifications to ADAMS waveforms or radar parameters, and azimuth restrictions and minimum range restrictions on turbine locations.12 The second phase of the MIT LL assessment to evaluate the feasibility of these proposed mitigation approaches began in July 2014 and is expected to be completed in mid- to late 2015.
Acknowledging the interference effects on ADAMS and desiring to keep project approvals moving forward, Pioneer Green offered to curtail its operations for 950–1,500 hours per year when dynamic RCS measurement testing is being performed. It should be noted that this testing is often conducted continuously over multiple weeks, at levels approaching 100 days a year. On the basis of the Pioneer Green proposal, Pentagon officials have continued working with the developer to negotiate the details of a curtailment agreement.
This arrangement would present an unacceptable risk to ongoing signature-collection operations because of the lack of government authority such an agreement would offer. If the company subsequently sold the operation to another interest, the existing agreement would not necessarily be enforceable. Furthermore, there are a number of additional wind-turbine projects in the region in various stages of planning, incentivized by attractive federal tax credits. With the expected expansion of wind farms in the area, it would become increasingly difficult to curtail energy production when forecasted or emergent test operations dictate. A requirement to curtail power generation for extended periods could eventually lead to significant economic loss for operators, and would likely lead to advocacy for relaxing the restrictions.
A curtailment agreement could also present operational-security concerns. Ongoing surveillance of RDT&E and acquisition-program activity by foreign intelligence agents is of continuous concern, particularly in ATR’s open-air range testing environment. Strict measures are in place to defend against these threats, but with the prospect of a high-visibility curtailment of wind-turbine activity, potential adversaries will be provided with unusually obvious cueing to high-sensitivity RCS testing.
The Economics of Displacement
The DOD and Navy have invested heavily in NAS Patuxent River as a result of prior Base Realignment and Closure decisions, and the result has been a singularly unique full-spectrum RDT&E and acquisition center of excellence. This includes the aggregation of end-to-end capabilities that exist nowhere else in the world. It is estimated that well over $3 billion has been invested in NAVAIR critical infrastructure at Patuxent River in recent years. The investment cost per acre of approximately $408,460 is significantly greater than the average of all Navy bases.13 The cost to relocate the ADAMS facility to an alternate location has been estimated at more than $100 million. ADAMS displacement would sever the intrinsic coupling of numerous critical facilities, and decouple T&E processes, workforce, and data networks that are highly leveraged across the organizations.
The economics associated with the wind farm do not present a compelling rationale for authorizing this project in light of the potentially deleterious effects on the Patuxent River economic engine. Advocates for the project claim that the estimated $200 million investment project will bring in several hundred temporary jobs, and result in $44 million in future tax revenues during a 40-year operating period, on average about $1 million per year. Follow-on positions to sustain operations are expected to total about five to ten individuals.14 By contrast, the Maryland Department of Business and Economic Development estimates that Patuxent River contributes $7.5 billion a year to Maryland’s economy.15 There are approximately 41,000 local jobs that support the defense-related work performed at Patuxent River, and it is estimated that 70–80 percent of the economy of the adjoining St. Mary’s County is fueled by operations at Patuxent River.
The economic impact could be severe to a large test program from even a single day of delayed or canceled operations, upwards of $1 million per day to a major development program. Several large active programs have made significant investment in ADAMS in recent years, and at least one has expressed concerns that a curtailment agreement will be insufficient to protect critical T&E schedules. The 2014 Report to Congress on Sustainable Ranges, submitted by the DOD’s Head of Personnel and Readiness, highlighted that the Pioneer Green project is one of the office’s greatest concerns. The report states that the “proposed renewable-energy development near Navy facilities at Patuxent River, MD . . . could cause significant degradation to the Navy mission, and it is unclear if mitigation efforts will eliminate the potential impacts to Navy readiness.”16
Among the other negative consequences of wind-turbine projects, there also is growing concern about the impacts of the large turbine blades to the resident bald eagle, other native wildlife, and migratory bird populations. The bald eagle population in the Eastern Shore region has made a recovery in recent years. There are estimated to be 30 nests of the species within a ten-mile radius of the proposed construction zone in Somerset County, and three nests within the immediate location of the planned facility. The U.S. Fish and Wildlife Service has declared the area to be “extremely attractive to the birds” and has warned Pioneer Green that their project “appears to present significant risk to eagles and urged that the planning be descoped.” At the originally planned size, the agency projected that the turbine blades could kill up to 43 eagles a year. Pioneer Green estimates were considerably lower, ranging from 15 to 18 birds annually. Even at that level, though, the estimated deaths would be larger than from any other planned project across the United States.17
Reconciling a Way Forward
In response to widespread concerns over wind-turbine interference with Patuxent River testing, a draft bill was overwhelmingly approved by the Maryland House and Senate in the 2014 legislative session that would have placed a one-year moratorium on the Pioneer Green project until the planned MIT LL study of mitigation options was completed. Despite the strong support for the bill in the Maryland legislature and direct personal appeals from Senators Barbara Mikulski (D-MD) and Benjamin Cardin (D-MD) and Congressman Steny Hoyer (D-MD), Governor Martin O’Malley vetoed the bill on 16 May 2014. In the Senate Appropriation Committee’s report of the Fiscal Year 2015 defense-spending bill, Senator Mikulski introduced language barring the Navy from reaching a deal with Pioneer Green to turn off the turbines during ADAMS testing at Pax River until MIT LL completes its study.
The legitimate competing interests of national security and energy security must be adjudicated in an environment of full disclosure and respectful dialogue. There are frequent reminders that national security and energy security are linked, and that if we effectively harmonize them America will be well on its way to a more secure and affordable future. Notwithstanding, when these objectives are juxtaposed on the basis of their objective merits, it can be argued that the downside risks of the currently planned wind farm to national security do not justify the upside economic potential. Alternative courses of action are available to ensure that wind-energy potential is realized while ensuring an interference-free environment for continuation of the critical ADAMS mission.
Additional time is required for completion of the MIT LL study to identify the value proposition of several potential mitigation measures to be considered by the Navy. Until this study is completed in 2015, it is highly imprudent to take any further steps to authorize the Pioneer Green project. Upon completion of the study, the service must evaluate the technical feasibility and cost effectiveness of the mitigation options. Little discussion has been held to understand the options available to adjust the planned location of the wind farm and modify tower height to prevent ADAMS radar-lobe interference. This information must be made available to the Navy and considered among the range of available mitigation options. Expedient but ineffective and ultimately potentially harmful solutions such as a curtailment memorandum of agreement should be dismissed outright for operational, economic, and security reasons. Additional research investment must be made in those technologies that demonstrate promise in resolving wind-turbine interference, as technology has the potential to become one of the DOD’s primary means of protection against mission impact. Finally, this current issue highlights the necessity of requiring earlier detailed discussions between commercial energy interests and all appropriate levels of the DOD and the services concerning the nature of projects with encroachment potential.
The strained process that has played out in dealing with the Pioneer Green project spotlights the essential need for systematic analysis earlier in the approval time line, before potentially damaging actions are too quickly accepted on the basis of inadequate due diligence. Our nation’s security interests deserve no less.
1. Nighthawks Over Iraq: A Chronology of the F-117A Nighthawk Stealth Fighter in Operations Desert Shield and Desert Storm: Special Study 37FW-HO-91-1 (Office of History: Headquarters 37th Fighter Wing, 12th Air Force, Tactical Air Command, 9 January 1992).
2. The United States Navy in “Desert Shield”/“Desert Storm” (Washington, DC: Office of the Chief of Naval Operations, Ser 00/lU500179, 15 May 1991).
3. American Wind Energy Association website, www.awea.org/resources.
5. Andrew Shchuka and Inderbir Sandhu, “Air Traffic Control Wind Farm Interference Mitigation,” Technology Today: Highlighting Raytheon’s Technology, 2012, no. 2, 28–31, http://www.raytheon.com/news/technology_today/archive/2012_i2.pdf.
7. Lisa Linowes, “Wind Energy and Radar: A National Security Issue,” Master Resource (energy blog), 26 September 2011, www.masterresource.org/2011/09/wind-radar-national-security/#sthash.nrZk0QW0.dpuf.
8. Statement of the Honorable Dennis V. McGinn, Assistant Secretary of the Navy (Energy, Installations, and Environment) before the Subcommittee on Readiness and Management Support of the Senate Armed Services Committee, 2 April 2014.
9. Matthew Hay Brown, “Wind Energy Plans Pose Challenge to Navy Testing,” Baltimore Sun, 16 November 2011.
11. Robert Work, “Great Bay Energy Center Project,” letter to Secretary of Transportation Anthony Foxx, 30 October 2014.
12. Ken Cole and Allen Hearn, “Wind Energy Mitigation: ADAMS Radar,” MIT LL Briefing, 21 May 2012.
13. Strength, Weaknesses, Opportunities and Threats (SWOT) Analysis of Naval Air Station Patuxent River & Associated Facilities (Alexandria, VA: Public Private Solutions Group, May 2014).
14. Todd Morgan, St. Mary’s County Board of County Commissioners, letter to the editor, The Enterprise, 3 May 2014.
15. Statement of Congressman Steny H. Hoyer (MD-5) before the Maryland Senate Finance Committee in support of H.B. 1168, 1 April 2014.
16. Nicole Clark, “Why Wind Turbines Ruffle Pax River Supporters,” Southern Maryland News, 15 April 2014.
17. Timothy B. Wheeler, “Eastern Shore Wind Project Confronts Eagles, Navy,” Baltimore Sun, 28 April 2013.