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The Need for Land-Use Planning for AirportsFAA Advisory Circular 150/5050-6, Airport Land -Use Compatibility Planning states: "There are existing compatibility problems around many airports; conflicts between airports and their urban environments are evident across the United States. This represents a serious confrontation between two important characteristics of urban economics - the need for airports which meet transportation needs and the continuing demand for urban expansion. Airport owners are finding essential expansion to be difficult and expensive or even impossible at any cost. New residential and noise sensitive development seems to surround the airport on all sides and is the source of continual threat of law suits for noise damage. On the other hand, ordinary citizens with investments in homes view the airport and its noisy aircraft as a threat to both hearing and peace of mind. To them the airport seems to be ever expanding, with more and larger jets added every year. The objective of airport -land use compatibility planning and implementation is the achievement and maintenance of compatibility between the airport and its environs. Inherent in this objective is the assurance that the airport can maintain or expand its size and level of operations to satisfy existing and future aviation demands and that persons who live, work, or own property near the airport may enjoy a maximum amount of freedom from noise or other adverse impacts of the airport. Equally important is the protection of the public investment in n facility for which there may be no feasible future replacement. The compatibility plan includes both a physical plan and an implementation program. It is normally prepared through the cooperative efforts of the airport sponsor and the local planning agency(s). Inputs from both airport users and citizens affected by the planning are essential to the study effort and are best obtained through a citizen participation program." "While most planners and airport sponsors will admit the present system of preserving compatible land use around airports isn't working, it may be more difficult to let go of concepts and policies upon which the system is based and which have proven faulty. The first assumption is that FAA grant assurances will result in compatible land use planning and implementation around airports. - MT. Systems Plan 1 5/29/97 The federal government historically maintains that land use around an airport is the sponsor's responsibility, yet the result has been less than satisfactory. The reason for the present system's failure may rest with the lack of incentives or sanctions for local governments to comply", wrote Katherine L. Houk.' "Only a mix of policies mandated at the state level and implemented by local governments is effective in preserving resource land," writes Arthur C. Nelson2. The development of models must also include, "...cultural preference, regulatory systems, political structures, and prevailing ideologies," adds L.S. Bourne ;3 i.e.," an airport does not exist in isolation, but should be a land use integrated into the total community environment. Airport sponsors will have less opportunities in the future to deal with incompatible land uses. The airport sponsor has the ultimate liability regarding land use. "Finally, one old policy needs to be given new emphasis. Airports are not compatible with residential uses, whether single or multi -family dwellings. Time and again, local governments have changed industrial zoning around airports to allow one or more developers to construct homes too close to an airport"'. An important airport land use compatibility issue is safety. This issue includes both the safety of the public on the ground and the safety of flight operations. A primary concern in achieving airport land use compatibility involves safety at and around an airport. All modes of transportation, inherently, pose some safety risk. It is important to identify those safety risks that are associated with air transportation in order to minimize the consequences of accident potentials. Specific areas near airports are exposed to various levels of accident potential. Identifying and protecting these specific areas around an airport through effective land use controls is essential to ensuring the safe and efficient operation of an airport and in protecting the public from the impacts of a potential aircraft accident. Areas around the airport also should 11(atherine L. Houk, Alternative Models for Developing Compatible Land Use Around Airports, a paper submitted in partial fulfillment for AAAE Certification. 2Arthur C. Nelson, "Preserving Prime Farmland in the Face of Urbanization: Lessons from Oregon", APA Journal, Autumn, 1992. 3L.S. Bourne, "Self -Fulfilling Prophecies? Decentralization, Inner City Decline, and the Quality of Urban Life", APA Journal, Autumn, 1992. MT. Systems Plan 2 5/29/97 be free of development that could pose a hazard to pilots operating aircraft in the airport environs. 1. Safety Impacts Complex safety issues are major factors which affect pilots, airports, and surrounding airport land uses. There are several factors that determine, from a safety perspective, which areas around an airport need to be protected. These factors include: the phase of operation during which aircraft accidents most often occur, the cause of these accidents, and the location of these accidents relative to the airport. Data from the National Transportation Safety Board (NTSB) regarding these factors are available to determine these areas. The NTSB maintains extensive data on air carrier and general aviation accidents and their causes. Table 1 shows the number of commercial and general aviation aircraft accidents that occurred during each portion of flight in 1990. From an off -airport land use planning perspective, the characteristics of accidents near airports are of the greatest concern. The statistics presented in Table 1 show that, in 1990, 60 percent (28.0 and 32.0) of all commercial aircraft accidents and 64.1 percent (40.0 and 24.1) of all general aviation aircraft accidents occurred during the landing or takeoff portions of flight. The conclusion that most of the risk involved with air transportation is associated with the takeoff and landing portions of flight is supported by these statistics. The critical areas at an airport that need to be secured and protected from a land use compatibility standpoint include the approach paths and departure paths to the runways. To enhance airport safety it is important to maintain obstruction -free airport airspace and a reasonable amount of vacant land at both ends of each runway. Areas to be maintained and the dimensions of these areas are dependent upon the type of aircraft that operate at the airport. MT. Systems Plan 3 5/29/97 Table 1 NUMBER OF ACCIDENTS BY PHASE OF AIRCRAFT OPERATION IN 1990 Number of Accidents in 1990 Phase of Operation Commercial General Aviation Approach/Descent/Landing 7 (28.0%) 897 (40.0%) Takeoff/Climb 8 (32.0%) 540 (24.1%) Cruise 4 (16.0%) 369 16.5%) Taxi 4 (16.0%) 61 (2.7%) Static 2 (8.0%) 23 (1.2%) Maneuvering 0 (0%) 303 (13.5%) Other/Not Reported 0 (0%) 47 (2.0%) 25 Source: National Transportation Safety Board (100%) 2,240 (100.0%) In addition to knowing the phase of operation during which aircraft accidents are most likely to occur, the most frequent causes of aircraft accidents should be identified. Identifying the cause of accidents as it relates to development activities is important to land use compatibility planning. Table 2 identifies the causes of the aircraft accidents that occurred in 1990. In some cases, more than one factor contributed to an accident. Data presented in Table 2 indicate that commercial aviation aircraft accidents are most often attributed to pilot error. General aviation aircraft accidents, however, are often related to the terrain and obstructions surrounding an airport. In 1990, terrain ranked as the fourth leading factor associated with general aviation aircraft accidents. Conflicts with objects, such as trees and wires, ranked as the fifth leading factor associated with general aviation accidents. A pilot's preoccupation with the terrain and structures immediately surrounding an airport can contribute to accidents. Structures in the approach path of a runway also contribute to aircraft accidents. Clearly, for the safety of both air travelers and the general public, it is best to maintain obstruction -free airspace as part of compatible land use planning for the area around each airport. MT. Systems Plan 4 5/29/97 Table 2 Cause of Factors Associated With Aircraft Accidents in 1990 Number of Related Accidents Cause/Factor Commercial General Aviation Pilot 10 1800 Terrain 0 454 Weather 7 485 Propulsion System/Controls 2 486 Object (tree, wire, etc.) 1 187 Other Person (not aboard) 7 176 Light Conditions 1 127 Landing Gear 1 68 Systems/Equipment/Instruments 2 83 Airframe 0 37 Flight Control System 0 43 Airport/Airways Facilities, NAVAIDs 2 14 Other Person (Aboard) 4 16 Source: National Transportation Safety Board I Perhaps the most critical factor in determining which areas around an airport should be protected is knowing where aircraft accidents occur. Data compiled by the NTSB indicate that the largest number of aircraft accidents occur on airport property. Specific data regarding the location of general aviation aircraft accidents, relative to the airports' location, are also available from the NTSB. With regard to, generar aviation aircraft accidents, data from the NTSB indicate that roughly 45 percent of all aircraft accidents occurred on airport property, while 15 percent occurred within one mile of the airport, and 40 percent occurred beyond one mile of the airport. Considering the general aviation aircraft accidents that occurred within one mile of the airport, 33 percent of these occurred within one -quarter mile of the airport, 29 MT. Systems Plan 5 5/29/97 percent occurred in the airport traffic pattern; the remaining 38 percent occurred within one mile of the airport. These data suggest that land use under the airport traffic pattern and within one -quarter mile of an airport should be considered, in addition to the land use off the approach ends to the runways, when addressing compatible airport land use. There are three basic approaches to attaining a high degree of safety compatibility around an airport: limiting the density of development; providing open areas for emergency aircraft landings; and limiting the height of structures, which is treated as a separate issue in another aspect of this study. a. Density Development A primary means of limiting the risks of damage or injury to persons or property on the ground due to near -airport aircraft accidents is to limit the density of land use development in these areas. The question of where to set these limits is dependent upon both the probability of an accident and the degree of risk that the community finds acceptable. From the previous sections, it is clear that accident probabilities increase with closer proximity to runway ends both because of greater concentration of aircraft over that area and because aircraft are flying at low altitude. The areas where aircraft regularly fly less than 500 feet above the ground are regarded as the most critical. Low flight altitudes present the greatest risks because they offer pilots less opportunity to recover from unexpected occurrences. Because aircraft are turning to follow the traffic pattern, this area encompasses more than just the area beneath the FAR Part 77 approach surface. Turns mostly take place between 2,000 and 5,000 feet from the runway end, depending upon the aircraft type, the number in the traffic pattern, and the pilot's flying techniques. These points raise the question of the degree of risk to which adjacent uses will be subjected. Perhaps the .best measure of development density in this context is the number of persons per acre. Because the risks differ inside a building versus outside, different standards are often applied for each condition. Some airports and local communities have set development density limitations ranging from 25 to 100 people for various parts of a runway approach corridor. Shopping centers are likely to - average about 75 people per acre and restaurants are often over 100. In general, high density residential development and places of public assembly should not be permitted in the airport's approach corridors. MT. Systems Plan 6 5/29/97 Another facet of the safety\density issue is how to reduce the risks for the occupants of an aircraft in the event that an emergency landing cannot be avoided. Given that aircraft are normally controllable during an emergency descent, pilots will head for the best available open space if they cannot reach the airport. An open area does not have to be very large to enable a successful landing for the occupants to survive the accident with limited injury. Because the pilot's decision in selecting an emergency landing site is reduced as the aircraft's altitude decreases, open areas should preferably be spaced more closely in those locations overflown at low altitude. C. Height of Structures Ordinances for height restriction as per Part 77 is addressed in a separate section. d. Lights Lights that shine upward are potentially hazardous since they can detract from a pilot's ability to identify an airport at night. A pilot may perceive such lights from adjacent land uses as part of the airport and/or runway lights. e. Glare Reflective surfaces can also produce a blinding glare, distracting pilots. Other visual difficulties can result from smoke generated by nearby business, industry, or field burning operations. f. Smoke Smoke can create severe visual difficulties when a pilot is either looking for an airport or preparing to take -off or land. An extensive amount of smoke can drastically curtail airport operations. Dust, fog, and steam, which all contribute to reduced visibility, can limit the effectiveness of .an airport. g. Electronic Interference Land uses that airports. Such communications. generate electronic transmissions should not be permitted near_ uses can interfere with aviation navigational signals and radio MT. Systems Plan 7 5/29/97 h. Bird Attractants Land uses such as water impoundments, garbage dumps, sanitary landfills, or sewage treatment plants often attract birds. Increased numbers of birds around airports increase the possibility of collisions between birds and aircraft. Damage to an aircraft and its occupants from a bird strike can be devastating. FAA Order 5200.5 Guidance Concerning Sanitary Landfills on or Near Air{Zorts states that sanitary landfills, because of their bird attractive qualities, are considered to be an incompatible land use if located within specified distances as cited by the FAA. As stated in FAA Order 5050 4A Airport Environmental Handbook, the FAA advises against locating such facilities within 5,000 feet of all runways accommodating or planned to accommodate piston -type aircraft, and within 10,000 feet of all runways accommodating or planned to accommodate turbine (jet) powered aircraft. These other potentially hazardous conditions should be recognized when planning compatible land use in the airport environs. In general, places of public assembly; distracting lights, glare, smoke, electronic interference; and bird attractors should not be within runway protection zones, approach zones, transitional zones, or beneath the airport traffic pattern. Additionally, sources emitting electronic interference and bird attractors are not acceptable forms of land use within the horizontal and conical zones. For those concerned with compatible land use in the airport environs, it is best to take steps to protect an airport before incompatible land use occurs which results in either safety or noise related problems. Planners have a number of "preventative measures" which they can consider adopting or implementing to prevent encroachment of incompatible activities into areas around airports which should be protected to ensure safety and noise compatibility. If incompatible land use or activities already exist in the airport environs, "corrective actions" can be taken. a. Preventative Measures It is always best to take actions that will prevent incompatible land use, as opposed to taking action to correct such activities after the fact. Planners have at their disposal a number of approaches that can be considered to prevent the development of activities or land use in the airport environs which would be incompatible from a safety or noise standpoint. Preventative measures can generally be divided into three categories: Planning, Ordinances, and Acquisition. These preventative measures are discussed in the following sections. MT. Systems Plan 8 5/29/97 • Any actions taken to promote compatible land use in the airport environs should be directed by an overall plan which is formulated based on safety related concerns and criteria discussed earlier in these guidelines. Initial planning steps that should guide preventative measures to insure compatible land use are discussed in the following sections. Planners have at their disposal ordinances which can be adopted to control both the height of development in the airport environs (necessary to comply with FAR Part 77) and also land use that is permitted within the Airport's zone of influence. Adopting both height and land use related control ordinances before development occurs in the airport environs is the best approach to insure long-term land use compatibility. a. Zoning Zoning is an exercise of the police powers of state and local governments which designate the use permitted on each parcel of land. The purpose of zoning is to designate those areas of the community most suitable for particular land uses. A zoning ordinance includes a map which delineates various land use zones called districts. The uses permitted in each district are also stated and defined in the zoning ordinance. The primary advantage of zoning is that it can promote compatibility while leaving the land in question in private ownership, on the tax rolls, and in a mode to produce economically. At the same time, zoning is subject to change and must be continually evaluated if it is to remain a viable land use compatibility tool. For zoning to be viable, there should be a reasonable present or future need for each designated land use. Zoning is the most commonly used form of land use control. Used within its limitations, zoning is the preferred method for controlling land use to achieve airport -environs compatibility. Zoning controls need careful tailoring in order to satisfy both the characteristics of the airport and the special conditions affecting the community. It is important for on - airport property and off -airport property to be appropriately zoned, so that required airport development can occur easily. There are generally three types of zoning that can be used in the airport environs to support compatible land use strategies developed in a comprehensive plan. These are: airport impact zoning, airport overlay zoning, and airport development zoning. MT. Systems Plan 9 5/29/97 An Airport Impact Zone is a separate zone used to place land use restrictions on land impacted by airport operations. An Airport Impact Zone establishes a new zoning designation which replaces the existing zoning designation, conditions, and permitted uses. This type of zoning can be used to limit development in areas subjected to moderate to severe noise impacts or beneath airport approach surfaces. 2. Airport Development Zonint Like the Airport Impact Zone, the Airport Development Zone establishes a new zoning designation. This type of zoning for airports often replaces "Industrial" or "Public Facility" classifications or other designations currently given to the airport site and immediate vicinity. Airport property that is reasonably confined to the airport area, areas needed for anticipated facility growth and airport -related industry and areas within the boundaries of RPZs should be encompassed within the Airport Development Zone. 3. Airport Overlay Zoning An Airport Overlay Zone maintains the existing zoning designation, but places additional conditions on the activities and uses that can occur in the area beneath the overlay zone. An Airport Overlay Zone can be used to limit the height of objects surrounding an airport; restricts uses that produce hazardous conditions that could distract a pilot during critical phases of flight, such as smoke and distracting lights, and limit uses for locations subjected to significant noise levels or within safety zones. a. Height Restrictions As stated earlier, height restriction zoning is discussed in another area of this study. 4. Acquisition Acquisition strategies for land use control and development are most effective if they are used in preventative mode. As a preventative strategy, acquisition techniques are generally less controversial and costly to implement. It is important to note, however,_ that acquisition strategies can also be employed as "corrective" actions when incompatibilities already exist related to various Federal and State safety and noise requirements. Planners should consider acquisition strategies described in this section in both the preventative measures and the corrective actions categories. MT. Systems Plan 10 5/29/97 a. Land Purchase Land purchase in fee simple by the airport is the most positive of all forms of land use controls, but it is usually the most expensive. It is recommended by the FAA, however, that airport proprietors own the property under the runway approach and departure areas, at least to the limits of the RPZ. Purchase of land within severely noise impacted areas and Runway Protection Zones is eligible for funding through the FAA if the airport is included in the NPIAS. It is preferable that local officials try to protect other land in the airport environs through comprehensive planning and zoning first, before purchasing, since this method is costly. On the other hand, variations of this method include land purchase with either resale for compatible use (land banking with restrictive covenants) or use for a compatible public purpose. Under this scenario, costs may be effectively reduced and considered to be more reasonable. b. Easements Easements may be used as an effective and permanent form of land use control to promote land use compatibility in.the airport environs. An easement is a right held by one person to make use of the land of another for a limited purpose. The FAA defines three basic degrees of avigation and hazard easements. Table 4 describes the rights acquired under each type of avigation and hazard easement. One major advantage of easements is that they can be permanent, whereas zoning can, in some circumstances, be changed. Additionally, easements often may be acquired for a fraction of the total value associated with the fee simple purchase of the land and thus they can be less expensive. Some easements also restrict places of public assembly. The FAA states churches, schools, office buildings and stadiums typify places of public assembly. MT. Systems Plan 11 5/29/97 Table 4 Basic Types of Avigation and Hazard Easements Type of Avigation/Hazard Easement Rights Acquired 1 Right -of -flight at any altitude above the approach surface. 2 Prevents any obstruction above approach surface. 3 Right to cause noise, vibrations, Model Avigation and Hazard Easement fumes, dust, and fuel particles. 4 Prohibits creation of electrical interference or unusual lighting. 5 Grants right -of -entry to remove trees, buildings, etc., above approach surface. 1 Right -of -flight above approach slope surface (20:1, 34:1, 50:1) 2 Prohibits any obstruction above approach slope surface. 3 Right -of -entry to remove any Limited Avigation Easement structure or growth above approach slope surface. 1 Prohibits any structures, growths or obstructions above approach slope surface (20:1, 34:1, 50:1) Clearance Easement 2 Right -of -entry to remove, mark, or light any structures or growths above approach slope surface. Source: Federal Aviation Administration Easements can be an effective strategy for assuring compatible development around airports. In the context of airport compatibility planning, easements may take several forms, such as a positive easement which allows the right of avigation a,nd the right to make noise over someone's property, or a negative easement which prevents the creation or continuation of incompatible land uses on the property. Acquisition of easements does not by and of itself change incompatible land use to compatible use or reduce the impact that airport operations have on the property, but the easement acquisition price can and should be dedicated to making the necessary change in use or providing soundproofing measures to achieve compatibility with the airport. MT. Systems Plan 12 5/29/97 Easements can be obtained in a number of ways including purchase, condemnation, and dedication (either voluntary or required at the time of subdivision). Easements may be obtained at the time of most land use decisions. An avigation or hazard easement can be used to prohibit the creation of electrical interference or unusual lighting; prevent any obstruction from protruding into the approach surface; and provide the right-of-way to remove obstructions, such as trees, from above the approach surface. An avigation or hazard easement exists within defined airspace area. C. Purchase of Development Rights Purchase of Development Rights (PDR) involves the use of various "rights" associated with a parcel of land. Under the PDR concept, some of the property's development rights are purchased. For example, land identified within the critical corridor of an extended runway approach could be kept in open space or agricultural use and its development rights for residential use purchased by the airport. In order to be a viable option, the PDR approach must be fully coordinated with an overall planning and zoning process; this is best achieved through the use of planned zoning. 4. Responsibilities for Corn ZEG���� The definition of compatible land use for an airport depends upon the planned use of the airport and the political will of the sponsoring unit of government. Compatible land use planning in the future cannot be driven by reaction to what has occurred, but on the stance of "where do we go from here". The planning of airports is often integrated into several different planning documents. The impact of the airport on community land use is an important consideration in all planning processes. Planning for airports takes place on several levels. The various levels of planning include airport system planning, regional and comprehensive planning, and airport master planning. System planning considers the local airport as a part of a network of airports which provide air transportation for a large area such as the nation, a state, or a region. Regional and community comprehensive planning occur at the local level. At this level of planning, the airport is considered not only in terms of its impact on transportation, but in terms of its impact on the economy and the surrounding - environment. The airport is an important part of the total transportation system of the area, which can include road, water, and rail. At the master planning level, improvements necessary to meet operational demands are identified for a specific airport. MT. Systems Plan 13 5/29/97 With respect to land use planning, each comprehensive plan should be developed to identify compatible land use surrounding the airport; the master plan should show the areas of land that an airport should control via fee simple acquisition or easements. Although system plans, comprehensive plans, and airport master plans are prepared independently of one another, the value of each plan increases when one plan provides input for another. The first step in examining land use compatibility surrounding an airport is to identify whether or not existing incompatibilities exist today and whether or not adequate measures exist to prevent future incompatibility. As discussed in a previous section, safety, height restrictions, and noise must be considered when planning for land uses compatible with airport operations. The FAA has established safety criteria related to the height of objects in proximity to airports and in the approaches to airports that affect both the ground and the air. It is the intent of this study to provide airport owners with information that provides two ordinances which considers both_ safety and height criteria to direct the control of land use around airports. Note: Portions of the preceding discussion were adapted from "Oregon Airport Land Use Compatibility Guidelines" Nov. 1994. Prepared by: The Airport Technology and Planning Group, Inc. (Air Tech). A:\mtstate\faa-1nd.wpd MT. Systems Plan 14 5/29/97