CalPilots response to – Public Comment to Draft Environmental Impact Report (EIR), North Sky River
June 20, 2011
JACQUELYN R. KITCHEN, Planner III
Advanced Planning Division
Planning and Community Development Department
Kern County
2700 “M” Street, Suite 100
Bakersfield, CA 93301-2323
Re: Public Comment to Draft Environmental Impact Report (EIR), North Sky River and Jawbone Wind Energy Projects (SCH# 2010121042)
Dear Ms. Kitchen:
The California Pilots Association is a non-profit public benefit California Corporation formed in 1949. Its mission is to promote, preserve and protect the state’s general aviation airports and to advocate for safe and responsible development in areas that materially affect the operation of aircraft utilizing such airports.
In recent years CalPilots has viewed the convergence of competing interests between wind energy and California general aviation with great interest. California Pilots Assn. (CalPilots) has previously submitted public comment with regard to the placement of wind turbines in proximity to general aviation airports where the proposed wind turbines dangerously encroach onto the airspace surrounding active general aviation airports. In those comments we outlined our concern that proper safety analysis and full study be given to any decision regarding placement of wind turbines near any airport.
More than ever, the land surrounding America’s general aviation airports is attractive to energy developers. Historically, airport land use commissions were loath to permit incompatible land uses in areas surrounding general aviation airports when that use involves habitable structures. However, the question of whether such uses as solar reflector farms, small “peaker” power plants, or wind turbine farms are incompatible land uses is largely uncharted territory. CalPilots recognizes that sensible development of clean energy in prime wind energy regions such as Tehachapi-Mohave Wind Resource Area requires a balancing act between the widely recognized demand for clean energy, and the equal imperative to mitigate hazards to air navigation. 1 It is a complex equation. New and replacement turbines are nearly 500 feet tall. On the one hand, during former Governor Schwarzenegger’s tenure California adopted ambitious energy policy goals of meeting 33 percent of its electricity needs by the year 2020 from renewable resources. 2 On the other hand, wind energy developers find themselves hemmed in by competing demands of the military, environmental interests, recreational use and the myriad other interests identified in the Draft Environmental Impact Report (the “DEIR”). Moreover, CalPilots fully understands that developing wind energy stands as a powerful inducement to growth; it creates jobs, and is quickly becoming a major source of tax revenue for county governments.
Kelso Valley Airport (CN37) (hereinafter “Airport”) is a private airport located westnorthwest of the proposed wind turbine projects. The airport consists of two runways configured in a perpendicular fashion: runway 01/19 length 3,988 feet and runway 17/35 length 3,060 feet. The field elevation is 4,047 feet. Our understanding is the Kelso Valley Airport is and will be principally used as a glider airport. The California Pilots Association is concerned about the proposed construction of the North Sky River and Jawbone Wind Energy Projects that propose to erect a number of up to 500- foot tall wind turbine generators (“WTGs”) in the glide path of the gliders. It is of paramount importance that the Project be critically examined and if necessary modified to eliminate this safety hazard and allow the Airport and the Project to coexist.
First, let us be clear about what our concerns are not: first, California Pilots Association does not inquire into the propriety or review of conditional use permits for private airports, and the Association takes no position as to whether Kelso Valley Airport should receive a permit. That is a land use and zoning matter between the private land developer, the California Department of Transportation (“CalTrans”), and local government. Our understanding is that the owner of the Airport has applied, or will apply for a new conditional use permit. Second, CalPilots takes no position as to whether glider aircraft as a category of general aviation aircraft have any inherent “right” or license to fly in certain areas to take advantage of certain thermal (i.e., convective lift) generating topography. Rather, our position is that all general aviation should be conducted in accordance with sound principles of aeronautical safety, irrespective of the category or type of registered aircraft.
However, leaving aside for a moment the question of the approved future use of Kelso Valley Airport, the California Pilots Association does have significant concerns regarding the inadequacy of the substance and process by which the safety interests of the Airport and the economic interests of wind energy developers are balanced. Our concern would remain the same whether a private or public airport was at issue. A review of the DEIR reveals that the County has given no thought to the performance characteristics of the aircraft in question, the typical flight profiles or the issues of aeronautical judgment encountered by the pilot. These factors must be considered in any intelligent discussion of whether a wind turbine poses an hazard to air navigation. A glider and tow-plane combination performs a departure with a very shallow climb angle; the system is basically underpowered and is only exacerbated by a high density altitude on summer days.
3 Moreover, a modern glider wing is one of the most efficient airfoils ever designed with glide ratios in the range of 40-50:1. Hence a glider returns to the airport with a very shallow descent angle. Moreover, wind turbines are not merely solid obstacles of a given height to be overcome by a glider. Wind turbines create wake turbulence4 to which lightweight gliders are particularly vulnerable, and these effects too must be considered. These facts, not appreciated in the DEIR, should make clear that 500-foot tall 3 Ironically, conditions of high density altitude draw large numbers of gliders because these are also the conditions best suited to long, high altitude cross-country flights. However as we pointed out, we make no judgment as to whether pilots should fly in these conditions, but only observe that because a glider is a glider, they just do. 4 Wind turbine wake aerodynamics, Vermeera, S^rensenb, Crespoc, Progress in Aerospace Sciences 39 (2003) 467– 510, available online at www.sciencedirect.com wind turbines, if placed within sufficiently close proximity of an airport used for glider purposes, have considerable potential to pose a substantial risk to aeronautical safety. Yet the DEIR contains a scant three sentences regarding the Project’s safety hazard impacts on the Airport. There is no analysis of these impacts whatsoever; impacts that would be intuitively obvious and of concern to any pilot of any aircraft. Astonishingly, the DEIR arrives at the cursory conclusion that the impacts would be “less than significant.”
Great reliance is placed upon the provisions of Federal Aviation Regulation (FAR) Title 14, Part 77 as a means of mitigating aeronautical safety impacts of wind turbines. 5 However, sole reliance upon FAR Part 77 6 as an insurance policy against collisions between gliders and wind turbines is misplaced. 7 First, nothing in either Part 77 or its authorizing statute, 49 U.S.C. § 44718, grants the FAA the power to regulate how land is used insofar as structures that may penetrate navigable airspace are concerned. The FAA is not empowered to prohibit or limit proposed construction it deems dangerous to air navigation.” Second, the criteria involved with a hazard/no hazard determinations are not necessarily a litmus test. FAA Order JO 7400.2G Procedures for Handling Airspace Matters vests considerable discretion in the FAA to determine what, and what is not a hazard to air navigation. A structure that exceeds one or more of the standards in Part 77 is presumptively a hazard to air navigation. However, it does not logically follow that everything that does not exceed a Part 77 standard is not a hazard to air navigation. California Public Utilities Code §§21001 et seq. (the State Aeronautics Act, or “the Act”) defines “airport hazard” as any structure which obstructs the air space required for flight of aircraft in landing or taking off at an airport or which is otherwise hazardous to the landing or taking off. 8 A Part 77 finding of “no hazard” should be but one indicia among many for consideration when evaluating the safety of wind turbines in close proximity to an airport. Settling the question of whether the proposed wind turbines pose an issue of aeronautical safety at Kelso Valley airport or any airport for that matter, should not be made in a vacuum and should be subject to considerably more scrutiny than that represented in the DEIR.
Kindly direct responses to this letter to my e-mail address or direct line.
Sincerely,
Christopher P. Mannion
Vice President
CalPilots Region 5
1 Leora Broydo Vestel, New York Times “Wind Turbine Projects Run Into Resistance,” August 16, 2010.
2 Governor Edmund G. Brown, Jr. signed SBX1 2, on April 12, 2011 which requires one-third of the state’s electricity to come from renewable sources. The law increased California’s current 20 percent renewables portfolio standard target in 2010 to a 33 percent renewables portfolio standard by December 31, 2020.
3 Ironically, conditions of high density altitude draw large numbers of gliders because these are also the conditions best suited to long, high altitude cross-country flights. However as we pointed out, we make no judgment as to whether pilots should fly in these conditions, but only observe that because a glider is a glider, they just do.
4 Wind turbine wake aerodynamics, Vermeera, S^rensenb, Crespoc, Progress in Aerospace Sciences 39 (2003) 467–510, available online at www.sciencedirect.com
5 In pertinent part: “ Implementation of MM 4.8-8 as well as MM 4.10-1 would ensure that the proposed project is consistent with the Kern County ALUCP and would not impact operations of aircraft using Kern County airspace and accessing proximate public airports…” (emphasis supplied).
6 FAR Title 14, Part 77, establishes the standards for determining obstructions in navigable airspace, including height limitations on structures taller than 200 feet or within 20,000 feet (3.8 miles) of an airport.
7 We note that since Kelso Valley is a private airport, its permit for use does not derive from the Federal Aviation Administration (the “FAA”). Rather, that authority derives from the CalTrans Aeronautics Division. However as a practical matter California Public Utilities Code §§21001 et seq. (the State Aeronautics Act, or “the Act”) imposes by
reference the requirements of FAR Part 77 as a condition for issuing a permit.
8 “Airport hazard” means any structure, object of natural growth, or use of land, which obstructs the air space required for flight of aircraft in landing or taking off at an airport or which is otherwise hazardous to the landing or taking off. California Public Utilities Code Section 21017
