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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.

Weather is a major cause of aircraft accidents and incidents and the single largest contributor to air traffic system delays. Through improvements in the knowledge of current weather conditions and reliable forecasts, the Federal Aviation Administration (FAA) can improve aviation safety, increase system capacity, and enhance flight planning and fuel efficiency. The FAA has established an Aviation Weather Research (AWR) program to address specific requirements for weather support to aviation by providing the capability to generate more accurate and accessible weather observations, warnings, and forecasts and also by increasing the scientific understanding of atmospheric processes that spawn aviation weather hazards. The goal of AWR is to provide meteorological research that leads to the satisfaction of specific aviation weather requirements.

“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.

Average continuous flow rates for each type of aircraft exit were examined in 89 full-scale evacuation demonstrations. Passengers tend to form continuous lines at available exits when evacuating an airplane. The study concludes that, with rare exception, the passenger rates of egress from the same type exit on different make and model airplanes are not significantly different. Passenger cabin configuration, seat pitch, and aisle width have no significant bearing on the egress rates provided the aircraft certification requirements for minimum aisle width and exit accessibility are met. Injuries resulting from actual emergency evacuations and evacuation demonstrations are also examined.

This paper will discuss some considerations regarding man-machine interface during helicopter instrument flight. Several misconceptions have existed regarding FAA helicopter IFR certification. In response to some concerns pertaining to “excessive workload considerations,” designers have responded with several configurations. Some of these configurations have highlighted the need to educate the designer and the pilot population that the pilot must have the option to “actively participate” in the flight activity during helicopter IFR operations. “Active participation” includes the option of flying the vehicle through the normal flight controls. In addition, there has been some confusion regarding the terms “stability augmentation systems” and “autopilot.” Some individuals use the terms interchangeably. This paper will discuss the various lessons learned during FAA certification of helicopters for IFR flight from a certification test pilot's viewpoint.

Monitoring head accelerations as an indicator of possible brain injury may lead to faster identification of injury and treatments. This study investigates the skull-coupling of a tri-axial accelerometer mounted to a back molar and compares it with a tri-axial accelerometer inserted in the boney ear canal. These tri-axial accelerometers were mounted to three post mortem human surrogate (PMHS) skulls, and compared with a rigid, skull-mounted laboratory sensor reference cube. Each specimen was subjected to both a high-g loading from a vertical drop tower and a low frequency cyclic loading from a shaker device. The specimens were subjected to an approximate 150g input acceleration on the drop tower, and up to 10g at a frequency of 9Hz on the shaker device. Each specimen was tested on all three of the anatomical axes on both the drop tower and the cyclic shaker.

Since the first airplane was certified in 1927, the standard configuration has been with the main lifting surface or surfaces forward of the stabilizing surface. Although some of the advantages of the canard configuration were recognized quite early - by the Wright Brothers, for example - canard surfaces have been used to date only as additional control surfaces on some military airplanes, and on some amateur built airplanes. As a result, the Airworthiness Regulations of Reference 1 address only tail aft configurations. When FAA was first approached regarding certification of a canard configured small airplane, an FAA/Industry Empennage Loads Working Group was formed to develop technical proposals for the necessary rule changes and policy. The concerns addressed by this working group are discussed in the following sections.

Microprocessor technology is allowing functions in aircraft to be implemented to a greater degree by digital process control than by conventional mechanical or electromechanical means. A review of this technology indicates a need for updated certification criteria. A high level of commitment to the technology such as fly-by-wire is completely beyond the scope of existing certification criteria. This paper emphasizes the areas of software validation levels, increased concern with basic power system qualification, and increased environmental concerns for electromagnetic interference and lightning.

Powered-lift aircraft, such as the V-22 tilt-rotor, are likely to spin-off a civil version. The present FAA airworthiness certification standards are not considered to be adequate for these unique aircraft. The FAA has drafted certification criteria and held a public conference to review the draft and identify significant technical certification issues that require further effort to establish correct standards for powered-lift aircraft. Some of those issues are 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.

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.

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.

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.

Unmanned Aircraft Systems (UAS) emerge as a viable, operational technology for potential civil and commercial applications in the National Airspace System (NAS). Although this new type of technology presents great potential, it also introduces a need for a thorough inquiry into its safety impact on the NAS. This study presents a systems-level approach to analyze the safety impact of introducing a new technology, such as UAS, into the NAS. Utilizing Safety Management Systems (SMS) principles and the existing regulatory structure, this paper outlines a methodology to determine a mandatory safety baseline for a specific area of interest regarding a new aviation technology, such as UAS Sense and Avoid. The proposed methodology is then employed to determine a baseline set of hazards and causal factors for the UAS Sense and Avoid problem domain and associated regulatory risk controls.

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.

The advent of digital electronics for use in civil aircraft, particularly the new technology represented by central processor and microprocessor controlled systems, represents a major challenge to the aviation industry. The Federal Aviation Administration (FAA) is charged with the responsibility of evaluating these systems to determine if they can be used safely. The complexity of these systems as compared to their analog counterparts in use today makes their evaluation difficult. This paper outlines the major concerns of the FAA with the use of software controlled digital systems for airborne applications. The methods which can be used by members of the aviation industry to obtain FAA certification of these systems are also discussed. The proposal of Special Committee SC-145 of the Radio Technical Commission for Aeronautics (RTCA) form the basis of the design methodology which is described for the successful development of the computer programs (software) to be used by these systems.

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.

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.

This paper compares the flammability of plastic automotive components to that of commodity, engineering, and specialty plastics as well as those used in commercial aircraft cabins with regard to performance in microscale combustion calorimetry tests. Not surprisingly, automotive components used in engine and passenger compartments are as flammable and ignitable as the commodity and engineering plastics of which they are made and much more flammable than those used in the interiors of aircraft.