State Aid to Airports is the basic airport aid program of the North Carolina Department of Transportation. Under the terms of North Carolina General Statutes Chapter 63, "the Department of Transportation is hereby authorized L L to provide State aid in the forms of loans and grants to cities, counties, and public airport authorities for the purpose of planning, acquiring, constructing, or improving municipal, county and other publicly owned or controlled airport facilities, and to authorize related programs of aviation safety, promotions, and long-range planning".

Eligible items under this program are those "projects, activities, or facilities as would in general be eligible for approval by the Federal Aviation Administration L L Further, airport terminals, security areas, seaplane bases, and heliports are eligible for state aid".

During the Fiscal Year, a modest amount of returned state funds are available for funding projects outside of the TIP process. These funds result from close-outs of projects with excess funds and cancellations, usually by the Sponsor, of projects which do not get underway. Amounts of funds available during the year vary, are usually limited, and normally may be made available only to high priority safety or airport preservation projects.

Funding under State Aid to Airports is dependent upon a number of factors and can range from 50% of the non-federal share to 90% of the non-federal share. The term "non-federal" share does not require that federal aid be in a project, but rather the total amount of the project, less any federal funds, be used to calculate the non-federal percentage of the project.

Until 1989, federal assistance to local airports had been from the FAA directly to cities, counties, and airport authorities. Unlike the federal highway and mass transit programs, there was very little formal state involvement in the process. There was growing concern on the part of the states that this approach did very little to help states develop an effective airport system meeting the goals and needs of their citizens and industries. In many cases FAA priorities were almost directly opposed to the priorities the states felt important in developing and upgrading their state system. To explore the possibility of an increased state role, the Congress passed the State Block Grant Program in 1989 to allow a limited number of states to administer at least some of the federal aid funds provided to their airports.

As approved, and still operated currently, Block Grant participant states administer funds for (1) general aviation airports, (2) airports designated as reliever general aviation, and (3) non-primary commercial airline airports (those with less than 10,000 annual enplaned passengers). The larger airline airports in the participating states continue to work directly with FAA for their funds. In North Carolina, this results in 63 of the 74 publicly owned airports being part of the Block Grant process, while the remaining 11 primary commercial service airports will continue to work directly with the FAA’s Atlanta Airports District Office on their grants.

The initial selection of states resulted in North Carolina, Illinois, and Missouri being designated as Block Grant states. Now there is a total of ten participating states.

The primary requirement for Block Grant eligibility is a federal regulation which stipulates that an airport must be listed in the National Plan of Integrated Airport Systems (NPIAS) in order to receive federal funds. Most of North Carolina’s publicly owned airports are in the NPIAS. Sponsors wishing federal assistance should first confirm their NPIAS status.

Several major differences exist between State Aid to Airports and Block Grant projects. First, the airport and the project must meet all eligibility requirements for federal funding. For example, State Aid to Airports can provide funds for terminals, but such buildings are ineligible for Block Grant funding. Airports receiving Block Grant funds must develop and implement a Minority Business Enterprise program for construction (and for operations if the grant is large enough). And Block Grant recipients must agree to be bound by the FAA standard grant assurances which dictate a large range of requirements which must be adhered to in operations and maintenance.

A more detailed discussion of assurances follows, but the two primary portions include a requirement to operate and maintain the airport as a public facility for a minimum of 20 years following signing of the grant. Also, Sponsors must agree that no land purchased with federal assistance will be sold, traded, or otherwise disposed of without federal approval. As apart of this stipulation, the Sponsor must credit the fair market value of such proceeds for airport use either through actually returning the funds to FAA or using the funds on the airport in an acceptable manner. These land requirements apply to parcels purchased solely with state funds as well.

Under the North Carolina DOT’s administration of Block Grants, an effort is made to make all grant processes as seamless as possible. Thus, the application, approval, and grant management for Block Grants is identical to that of State Aid to Airports. The only major differences involve item eligibility, special FAA provisions such as DBE, and the inclusion of the federal funds in each payment on the grant. Grant Agreements for Block Grant projects are essentially the same as for State Aid to Airports, administration and processing are likewise the same, and single payment is made containing both the federal and state shares of the project for each interim pay request.

• Approved December 2006 Project Recommendations
• Approved August 2006 Project Recommendations
• Approved Fiscal Year 2006 Project Recommendations
• Approved Fiscal Years 2007-2011 Tentative Allocations
• North Carolina General Aviation Airport Development Plan (NCGAADP)

Links to FAA's Southern Region Airport Layout Plan (ALP) Checklist and other useful planning resources are available at the Airports - Southern Region Planning & Capacity web page. Click here to go to that page.

Airport Pavement Management System Update

The Division of Aviation recently began the biennial process of updating its Pavement Management System (PMS) data in September 2006 for each of the publicly owned and operated general aviation airports in NC. This update is performed in large part by NCDOT Division of Highways Area Pavement Coordinators using the Pavement Condition Index (PCI) method of pavement evaluation as developed by the U.S. Army Corps of Engineers. The PCI method results in an objective score for each section of pavement from 0 to 100, with 100 being new pavement in perfect condition.

Through the use of the PCI evaluation and the expertise of the Pavement Coordinators, we at the Division of Aviation will be able to analyze and budget for the maintenance needs of each individual airport in an objective manner. We are anticipating all data collection efforts to be completed by Mid-December 2006 with data entry and analysis work completed by March 2007. Each airport can expect a copy of it's Pavement Management System results sometime in Spring 2007.

Statewide Airport Development Plan

Airport Development strives to provide an effective and safe aviation system that promotes economic development for the citizens of North Carolina. The Airport Development Section is currently updating a component of the Aviation System Plan by evaluating the public owned and operated airports statewide to provide an action plan for airport development that maximizes limited financial resources for system wide development, concentrates on safety, future needs, and promotes economic growth while not losing sight of the individual airport.

FAA Airport Master Record Inspections (5010 Program)

The Division of Aviation staff are conducting airport inspections at many of the public-use General Aviation (GA) airports statewide this year. Inspections are well underway and should be completed by the end of the calendar year. Approximately one hundred airports will be inspected. Data verified and collected during these inspections is used to update the FAA's Airport Master Record database. Some of the data includes general and facility information, runway and navigational aid data, and obstruction data. This database is made available to the public and the data is used extensively by people and organizations throughout the world. One of the most significant publications that is produced largely from the data is the FAA Airport Facility Directory (AFD) or also known to some as the "green book" based on the color of the book cover. The data is also heavily used by many governmental agencies when performing emergency planning and operations. If you have any questions regarding these inspections, please contact Marshall Sanderson at 919-840-0112.

Zoning Initiative

As of the beginning of 2004, the Division of Aviation requires that all airports receiving state and/or federal funding be required to have in place height zoning around their airport. Any airport requesting funds through this Division that does not have height zoning in place will not be eligible to receive federal and state funding. This requirement is being made to help protect the federal and state funds invested into the local airport. The Division would like to also encourage that land use zoning be enacted at and around the airport.

Navaids is an abbreviation for Navigational Aids. Navigational Aids are devices, both electronic and visual, that provide assistance to pilots for navigation in the enroute and landing phase of flight. In addition, automated weather reporting equipment is usually included under the umbrella of Navaids.

The primary enroute navigation systems are Very High Frequency Omnirange Station (VOR) and satellite based Global Positioning System (GPS). For the approach and landing portions of flight, there are, in order of precision, Instrument Landing System (ILS), Localizer (LOC), GPS, VOR, and Non-Direction Beacon (NDB). In addition to the just mentioned electronic or satellite systems, there are several types of approach lighting systems to aid the pilot in the landing phase after he has located the airport and is making his approach to the runway. These Navaids are divided into two categories, differentiated by method of funding, for both installation and maintenance. The categories are Federal and Non-Federal, usually referred to as Fed and Non-Fed. For the user, the difference is invisible, as both categories are required to maintain the same standards of accuracy by the FAA. The distinction is noted only to make you aware of the efforts, including funding of installations and maintenance that local and state agencies make to provide the Non-Fed portion of the system.

North Carolina has 74 public-owned public-use airports in our state. To support the enroute portion of flight, there are 16 VORs, 14 Fed and two Non-Fed. For the instrument approach phase there are 26 airports that have ILSs, about evenly divided between Fed and Non-Fed. There are 11 airports with Non-Fed LOCs and about 50 or so NDBs, about 40 Non-Fed and the rest Fed. In addition there are numerous approach lighting systems, approximately two-thirds Fed and one-third Non-Fed.

There are 49 airports with Automated Weather Observation Systems (AWOS) installed, with an additional nine sites in some phase of siting or installation. Twenty-two of these are Fed and 36 are Non-Fed.

All of the above listed Navaids support approximately 240 instrument approach procedures at 65 of the 74 public-owned public use airports. Of the remaining nine airports, two have instrument approach procedure being developed, three have geographical problems, such as mountains, that preclude an instrument approach for reasons of safety, two are unattended and or rarely used for commercial purposes, and one is located at the Wright Brothers Memorial and not intended for commercial use.

The Airport Maintenance Section assists all publicly owned and operated general aviation airports with state supported maintenance activities. The goal is to work cooperatively with the local airport and the Division of Highways toward projects that help protect and maintain a safe facility for the public. Maintenance items include and are not limited to airport pavements, drainage, and pavement markings with emphasis being placed on preventative maintenance.

• Layered Elastic Design for General Aviation Program
• Layered Elastic Design for General Aviation Manual

ABSTRACT

Development of a Reliable Methodology for Assessing the Structural Performance of General Aviation Pavements By

Bobby Walston, P.E. North Carolina Division of Aviation
1560 Mail Service Center, Raleigh, NC 27699-1560
Tele: (919) 840-0112; Fax: (919) 840-9267; e-mail:bwalston@dot.state.nc.us

Roy D. McQueen, P.E. McQueen & Associates, Ltd.
22863 Bryant Court, Suite 101, Sterling, VA 20166
Tele: (703) 709-2540; Fax: (703) 709-2535; e-mail: rdmcqueen@rdmcqueen.com

Existing pavement evaluation and design methodologies are primarily oriented toward larger, air carrier size aircraft, and do not adequately address the requirements at General Aviation (GA) airports, many of which consist of relatively thin flexible sections. Although GA pavements generally serve aircraft with gross weights of less than 30,000 lbs., most airports may need to accommodate heavier corporate or military aircraft on an occasional or periodic basis. Existing light aircraft design methods, such as those contained in Federal Aviation Administration (FAA) Advisory Circular 150/5320-6D, "Airport Pavement Design and Evaluation", are not capable of handling mixed traffic, aircraft over 30,000 lbs., or non-standard pavement sections.

To address these shortcomings and to augment its formal strength rating program, the North Carolina Division of Aviation (NCDOA) conducted a two year study during 1997 – 1999 to develop:

Standardized procedures for nondestructive testing (NDT), evaluation, and design of GA airport pavement structures; and Analytical software based on layered elastic design theory for evaluating GA airport pavement strength and "overload" operations.

Since most GA airport pavements consist of flexible pavements, the study focused on flexible pavements, only, although future expansion to include rigid pavements is possible.

For GA airport pavements, the results of the study will provide NCDOA, consultants and aviation agencies in other states, with greater flexibility to:

• Utilize NDT procedures and mechanistic design methods;
• Evaluate changes in operational weights, frequency and type of aircraft;
• Assess occasional, or one time, aircraft "overloads;
• Report pavement strength;
• Estimate theoretical structural life;
• Conduct sensitivity analyses; and
• Extend visually based pavement management systems to include structural analysis.

The approach to the study consisted of the following four primary elements, and included the participation of NCDOA, NC Division of Highways (NCDOH), FAA Technical Center, and Roy D. McQueen & Associates, Ltd.:

• Field Testing - Nondestructive and conventional tests were performed on one runway at each of six GA airports in different areas of North Carolina. The primary focus of the testing program was to standardize NDT procedures with the Falling Weight Deflectometer (FWD) and correlate FWD and conventional test results.
• Data Analysis - Back-calculated FWD subgrade moduli were correlated with CBR and laboratory resilient modulus data. The primary purpose of the data analysis segment was to provide data for development of failure algorithms and to allow direct input of back-calculated FWD subgrade modulus into the evaluation procedure.
• Subgrade Strain Criteria - The results of a literature search and design of FAA compliant pavements over a broad range of subgrade and traffic inputs formed the basis for a new subgrade strain failure criterion. The resultant subgrade strain criterion is a function of coverages (N) and back-calculated subgrade modulus (E).
• Development of Analytical Software – Layered elastic evaluation and design software was developed using the FAA’s LEDFAA software for air carrier pavement as a model. The new software, termed LEDGA, incorporates the new subgrade strain criterion, permits multiple aircraft analysis and evaluation of "overloads" based on cumulative damage concepts, and allows for variable load repetitions and surface thicknesses.

LEDGA version 1.2 software and documentation is available for downloading here. You may also call the NCDOT/Aviation office for a copy of the software on diskette. Call 919.840-0112.