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Although Unmanned Aircraft Systems (UAS) have now for some time been used in segregated airspace where separation from other air traffic can be assured, potential users have interests to deploy UAS in non segregated airspace. Recent technological and operational improvements give reason to believe that UAS safety and performance capabilities are maturing. But the skies can only really open up to UAS when there is an agreed upon UAS safety policy with commonly accepted UAS Safety Risk Management (SRM) processes enabling to show that the risks related to UAS operations in all the different airspace classes can be adequately controlled. The overall objective is to develop a UAS SRM framework, supporting regulators and applicants through provision of detailed guidelines for each SRM step to be conducted, including 1) system description, 2) hazard identification, 3) risk analysis, 4) risk assessment, 5) risk treatment.

NASA's Deep Space Network (DSN) uses high-power transmitters on its large antennas to communicate with spacecraft of NASA and its partner agencies. The prime reflectors of the DSN antennas are parabolic, at 34m and 70m in diameter. The DSN transmitters radiate Continuous Wave (CW) signals at 20 kW - 500 kW at X-band and S-band frequencies. The combination of antenna reflector size and high frequency results in a very narrow beam with extensive oscillating near-field pattern. Another unique feature of the DSN antennas is that they (and the radiated beam) move mostly at very slow sidereal rate, essentially identical in magnitude and at the opposite direction of Earth rotation.

Recent changes in DoD procurement directives have encouraged the purchase of civilian products for use in certain military applications. One such application is the upgrade of avionics suites with the Global Positioning System (GPS) in military air transport aircraft to meet joint civil-military operational requirements. This paper reviews the Commercial Off-the-Shelf (COTS) concept and the proper use of TSOs, ACs, and FARs in both the design and integration process.

This paper describes the recently established Commercial Aviation Alternative Fuel Initiative (CAAFI), including its goals and objectives, as well as presents an alternate fuel roadmap that was originally generated by industry and refined by the CAAFI stakeholders. CAAFI is designed to coordinate the development and commercialization of “drop-in” alternate fuels (i.e. fuels that can directly supplement or replace crude oil derived jet fuels), as well as exploring the long-term potential of other fuel options. The ultimate goal is to ensure an affordable and stable supply of environmentally progressive aviation fuels that will enable continued growth of commercial aviation. This initiative is organized into four sub-groups: Research and Development (R&D), certification, environment, and economics & business. The R&D group seeks to identify promising new drop-in alternate fuels, and to foster coordination of development efforts.

Many of the certification regulations in 14 CFR Part 25 are by design, broad and as such, can be subject to large differences in the interpretation of what constitutes adequate compliance. Advisory Circulars (AC's) were developed for many of the regulations to assist industry, as well as certification personnel, with what is considered an acceptable, but not the only means, of compliance. However, there are many regulations where no advisory material is available. In these cases, the “acceptable means” of compliance can vary to a greater degree among the various aircraft certification offices. This difficulty is aggravated as new applicants and regulatory personnel enter the certification field. Recent discussions and interpretations on the usage of an avionic unit's mean time between failure or MTBF for its detectable faults as the basic repair rate for undetected or latent faults, is a subject area where no significant advisory material exists.

“As we handle more operations and passengers in the air, we must make certain we have the capacity to handle increased traffic on the ground.” - Jane Garvey, FAA Administrator (4/20/98) The FAA Technical Center (Aviation System Analysis and Modeling Branch, ACT-520) has been responsive to the FAA Airport Capacity Program customers for the past 22 years, developing, testing, and applying airfield and airspace simulation models. More than 90 capacity studies have been completed with ACT-520 personnel contributing their technical expertise to the Airport Design Teams. The teams are comprised of FAA personnel, airport operators, air carriers, other airport users and aviation industry representatives at major airports throughout the US. Initial studies focused on modeling airport operations from final approach, taxi, gate operations and departure processing. Later in the program, local airspace studies were included in some airport study efforts.

A 10-foot-long fuselage section from a Boeing 737-100 airplane was dropped from a height of 14 feet generating a final impact velocity of 30 feet per second. The fuselage section was configured to simulate the load density at the maximum takeoff weight condition. The final weight of 8870 pounds included cabin seats, dummy occupants, overhead stowage bins with contents, and cargo compartment luggage. The fuselage section was instrumented with strain gages, accelerometers, and high-speed cameras. The fuselage sustained severe deformation of the cargo compartment. The luggage influenced the manner in which the fuselage crushed, affecting the gravitational (g) forces experienced by the test section. The seat tracks experienced 15 g's vertical deceleration. Although numerous fuselage structural members fractured during the test, a habitable environment was maintained for the occupants, and the impact was considered survivable.

As a part of its International Aging Aircraft Research Program, the Federal Aviation Administration is establishing a state-of-the-art Flight Loads Data Collection Program. Data collected in this program will provide the necessary mission profiles and load spectra information to characterize typical fleet service usage for the regional/commuter service life extension program. In addition, these data are applicable for both a safe life fatigue analysis and a damage tolerance fracture mechanics analysis. This paper describes the FAA approach and schedule for instrumenting fleet service aircraft, and the data reduction process.

Voice communications are crucial to safe and efficient air traffic operations. Controllers are required to use standard phraseology, and pilots are encouraged to use it when talking to controllers. Incomplete or inaccurate communications were implicated in mishaps such as the Tenerife accident. This research examined the frequency of phraseology deviations in a sample of 5,000 transmissions from 3 terminal facilities. The Aviation Topics-Speech Acts Taxonomy (ATSAT) was used to develop baseline data and analyze controller/pilot communications. Clearance instructions were transmitted most frequently and they contained a higher percentage of deviations from standard phraseology than any other speech act category. Identification of the types of errors typically associated with specific miscommunications could result in implementing new training approaches that ensure a higher compliance with standard procedures and improve standard phraseology usage.

Numerical simulations indicate that blast loading on aircraft structural joints can impart loading rates in excess of 10 Mlb/sec (ten million pounds per second, Reference 1). Experimental evidence, on the other hand, suggests that mechanical joint failure loads are highly loading rate dependent; for example, the failure load for a dynamically loaded tension joint can double from its static value. This paper discusses the progress and to-date findings of research on the assessment of strength failure of aircraft structural joints subjected to loading rates expected from an internal explosive detonation, and several associated experimental procedures to generate such dynamic loading. This work is conducted at MDC and at the University of Dayton Research Institute (UDRI) in support of the FAA Aircraft Hardening Program.

In the early design stages of the advanced technology high-bypass-ratio engines, it became evident that maintainability considerations and more effective maintenance concepts would be necessary to achieve higher reliability and more economically successful powerplants. This paper reviews the major design considerations from a maintainability standpoint. It describes the concepts developed specifically to provide more effective maintenance for the wide-body jets. It discusses the effectiveness of these programs, and provides an insight into new philosophies and trends envisioned by the Federal Aviation Administration for future maintenance management programs.

The present regulatory tool for assessment of aircraft smoke emission, the Ringelmann Chart, is described; some of the shortcomings associated with its use for aircraft are discussed; research and development efforts to improve on this system are described. The gaseous pollutants, their relative importance in an airport area and research underway or needed is also discussed.

Important provisions are highlighted with respect to the additional airworthiness standards being considered by the Federal Avaiation Administration for small airplanes capable of carrying more than 10 occupants which are intended for use in air taxi and commercial operations. Information is presented on the background leading to these provisions and on their impact on manufacturers and operators. These new standards would result in a significant increase in the level of safety which is more commensurate with the class of operation, the increased occupant capacity, and the expanded volume of operations anticipated for these airplanes.

The Federal Aviation Administration is charged with the promotion of aviation safety. It is made up of three levels of administration within which are the functional organizations that manage the FAA programs and services. The Flight Standards service, which develops and enforces all regulations affecting aircraft and airmen, is the functional organization directly responsible for promoting aviation safety. This paper describes the Flight Standards aviation safety program.

The Federal Aviation Administration has placed increasing emphasis on modern information systems to achieve safety improvements. The ASAS (Aviation Safety Analysis System) is a comprehensive new system to upgrade significantly the agency's ability to collect process and disseminate safety-related information.

The rapid growth in digital computer technology and display systems has impacted most aerospace disciplines. The designer manufacturer operator and even airplane passengers are all affected by this technology boom. The FAA in its role of certifying new aerospace products is no exception. This paper will emphasize the changing methodology of the FAA certification process with some specific examples of recent flight test programs.

Federal Aviation Administration philosophy regarding simulator use in the airman certification system is stated. Airman certification requirements, specified in the Federal Aviation Regulations, are expressed in behavioral terms. Distinctions between simulator uses for training, evaluation, and gaining operational experience are discussed. A methodology for determining systematically and objectively how simulators may be used for pilot performance evaluation is derived from instructional system design. An experimental design, appropriate for validation studies of pilot performance evaluations in simulators, is referenced.

In view of the fact that future generations of derivative or new aircraft will be faced with problems of increasing operating efficiency, new and more advanced technology will have to be introduced. To this end, the Federal Aviation Administration has been examining the certification question and has concluded that simulation may be increasingly important in the future certification activities. Through a contract with Lockheed Aircraft Company, the FAA will be able to review past use of industrial simulation in connection with certification.

This paper presents a description of several Federal Aviation Administration (FAA) incident data systems that contain information on events which result primarily from human error. These data systems include reports of near midair collisions, operational errors, pilot deviations, and events reported through the Aviation Safety Reporting System (ASRS). Over 17,000 incident reports are received and stored in these data bases annually. This paper discusses the information content of the data bases, reporting procedures, system limitations, proposed improvements, and uses of the data.