Windmills & Airspace Can We Work Together?

May 29, 2008 Windmills & Airspace Can We Work Together? J. Randolph Babbitt C O N F I D E N T I A L www.oliverwyman.com

Windmills & Airspace Overview of Airspace Issues For Wind Turbine Sites The FAA s Role and Procedures The FAA s Basic Steps The Basic Types of Airspace Impacts Identify The Potential Conflicts Resolving Adverse Impacts. Questions & Answers Source: 8pt Arial 1 Footnote Note: 1

Windmills & Airspace Overview of Airspace Issues For Wind Turbine Sites The FAA s Role and Procedures The FAA s Basic Steps The Basic Types of Airspace Impacts Identify The Potential Conflicts Resolving Adverse Impacts. Summary and Recommendations Source: 8pt Arial 1 Footnote Note: 2

The FAA s Role and Procedures The FAA has oversight of any object that could have an impact on the navigable airspace or communications/navigation technology of aviation (commercial or military) or Department of Defense (DOD) operations. One of the most important early goals in any wind project is obtain a Determination of No Hazard from the Federal Aviation Administration (FAA) meaning the project does not adversely affect air traffic or radar systems. The FAA requires that a Notice of Proposed Construction (Form 7460-1) be filed for any object that would extend more than 200 feet above ground level and / or closer than 20,000 feet to a public-use airport with a runway more than 3,200 feet long. Best business practice File the 7460 regardless 3

The FAA s Basic Steps The Proponent of any potential obstruction files form 7460 FAA will then undertake an initial aeronautical study and issue either a Determination of No Hazard to Air Navigation (DNH) and you may proceed with construction; or, FAA issues a Notice of Presumed Hazard (NPH) along with a technical analysis which will explain the cause of the NPH and the forecast impact on air operations. The proponent should request further study and circularization to interested parties which will include a public comment period After comments are received and there remains an operational impact, the FAA may offer to negotiate an acceptable height for a project that has received a DNH. If no agreement can be reached, FAA will issue a Determination of Hazard (DOH). That DOH can be appealed to FAA Administrator on the basis of technical flaws in the evaluation If unsuccessful, the only recourse remaining is to bring the issue before a Federal Court. 5

The Basic Types of Airspace Impacts Imaginary Surfaces Both aircraft flight routes and the airspace near airports provide defined space dedicated to the takeoff, travel, and landing of aircraft. You can imagine these spaces as three dimensional highways of airspace with very specific boundaries. These three dimensional highways are defined as imaginary surfaces. If an imaginary surface is penetrated by a constructed object (e.g., a turbine), the FAA will then do a more extensive study to determine whether the turbine poses an operational problem for the relevant airport or for a specific flight route between navigational aids or airports. If the penetration does not pose an operational impact it will be determined not to be a hazard. 7

Imaginary Surfaces Graphical Depiction COURTESY OF THE 8

Imaginary Surfaces Graphical & Google Earth View 9

The Basic Types of Airspace Impacts Operational Impacts Public airports utilize basic rules of operation for either visual flight rules (VFR) and instrument flight rules (IFR) and Operational impacts are those that affect either VFR or IFR operations. Examples would include: An increase in the minimum flight altitude in a specific area Having to modify procedures to divert air traffic away from an obstacle Increasing the minimum climb gradient (steepness) for airport departures Increasing the minimum descent altitude at the obstacle location for airport arrivals and approaches Airlines & commercial operators are generally resistant to operational changes that would increase workload in the cockpit during critical takeoff & landing periods or impose non-standard flight restrictions. 10

The Basic Types of Airspace Impacts Electromagnetic Interference (EMI) Experience has shown that wind turbines can degrade performance of air traffic control (ATC) or air defense radar. The problem is primarily the intermittent appearance of radar contacts at the location of the wind turbine because of blade rotation and the angle of the turbine For ATC radar the interference is generally limited to wind turbines that are within the radar line of sight. There is a difference between Primary and Secondary Radar Studies don t reflect significant impact on Secondary Radar DOD issues do focus on the impact on Primary Radar The problem diminishes significantly and linearly as distance increases between turbines and the radar facility 11

Identify The Potential Conflicts Most projects will find it cost beneficial to conduct a preliminary Airspace Analysis by a qualified consultant at the first planning stage of a project. This relatively inexpensive step will: Identify potential airspace and EMI issues and conflicts Avoid wasting time, money and effort Help determine the most efficient the site plan that will comply The FAA does offer a preliminary website review to identify radar issues, however there is considerable latitude by the FAA as part of its formal review of a Notice of Proposed Construction and the FAA s evaluation of potential conflicts with air traffic is significantly more objective than its evaluation of radar issues Don t overlook the people aspect. There are a variety of objections that can and will arise from the neighbors including noise generation, impediment to existing views and wild life concerns 13

Windmills & Airspace Overview of Airspace Issues For Wind Turbine Sites The FAA s Role and Procedures The FAA s Basic Steps The Basic Types of Airspace Impacts Identify The Potential Conflicts Resolving Adverse Impacts Questions & Answers Source: 8pt Arial 1 Footnote Note: 14

Resolving Adverse Impacts There are several possible avenues to mitigate Adverse Impacts The criteria does require that the adverse impact be substantial (meaning to routinely affect a high volume of traffic daily) and further study may well show the impact to be not substantial A modification of the height of a proposed turbine Position the turbine (s) at a greater distance from an airport or radar facility or further away from a specific approach or departure corridor Negotiate with the FAA to adopt a procedural change that would mitigate the problem The FAA s primary role is to protect the National Airspace, but they have proven to be most helpful in finding alternatives to accommodate and facilitate projects as long as those changes are not compromising safety 15

Windmills & Airspace Questions & Answers 17