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Many European airports are located in close proximity to residential or protected areas. Aircraft noise emissions caused by the landing and taking off of aircraft are a big problem in these areas. From an operational point of view, the method for reducing noise is to reduce traffic volume or change its organization, especially during the night. Some procedures and tools have been developed to support air traffic management in the implementation of operational constraints necessary to maintain noise at an acceptable level. The objective of this paper is to analyse the effectiveness of these tools. For this purpose, we have analysed existing methods of operational noise reduction, taking into account their influence on the structure, smoothness, punctuality and, especially, the safety of air traffic. As a result, existing risks have been identified, while methods have been proposed to combine two important air traffic service tasks: ensuring safety, while taking into account the environmental constraints, especially in relation to the acoustic climate.

The specificity of military flights operations imposes a number of requirements on aircraft. One of the main factors concerning the realization of the air task is the reliability of the engine. The most common cause of aircraft engine malfunctioning is the quality of the fuel supplied. This paper presents the factors affecting the quality of fuel supplied to aircraft and the procedures preventing the delivery of aircraft fuel, which could interfere with the operation of the aircraft engine.

Information on the suggested aircraft airspeeds can be obtained from flight manuals, but the actual airspeeds flown by an aircraft will vary based on the aircraft landing weight, airport altitude, wind conditions, and other Air-Traffic-Control related factors. The recent advent of new tools and an abundance of new, highly accurate aircraft surveillance data have enabled a reevaluation of past airspeed profile assumptions. The resulting analysis provides a stronger representation for airspeeds flown on final approach and initial departure by the aircraft types comprising a large percentage of U.S. Instrument Flight Rules operations. Furthermore, the time to fly is calculated to determine how long it takes the trailer aircraft to fly the distance to the point where the leader generates a particular portion of the wake. Although this work is performed to provide improved inputs for Recategorization Phase II analyses, the airspeed profiles derived from aircraft surveillance data will also be valuable to other...

Nowadays, besides safety issues, environmental protection is the main issue to be considered during the aircraft operations. Recorded total CO2 aviation emissions are approximately 2% of the Global Greenhouse Emissions with the approximated expected growth around 3-4% per year. Therefore, variety of standards and recommending practices have been developed to address aircraft noise and engine emissions embracing technological improvements, operating procedures, proper organization of air traffic, appropriate airport and land-use planning, and the use of market-based options. This paper is based on environmental pressures from long distance air transport with the focus on passenger transport. The paper deals with variety of parameters important for aircraft operations on ground. Those parameters could be grouped within safety, technical, infrastructural, weather, meteorological conditions, etc. It is not possible consider only one group of parameters since aircraft operations on ground present complex environment for the aircraft structure loads, weight limitation or cost efficiency flight performance. Nowadays, research of aircraft ground operations is much oriented to environmental protection and noise limitation issues which influent new technologies of aircraft building or equipment production or airport capacity and air side characteristics. The paper analyzes specific operation parameters related to aircraft capabilities and performance in order to understand the quality and cost efficiency while selecting certain aircraft from fleet to operate on origin/destination airport. Obtained results and final conclusions address future measures for minimizing the environmental pressures based on environmental trends in aviation to 2050 provided by ICAO and EASA.

Flight data of Beechcraft King Airs used as aerial supervision modules and lead aircraft by the U.S. Forest Service are analyzed. The operational conditions experienced by the airplanes are studied as well as the magnitude of the vertical loads. The airplanes are flown in four different types of missions in U.S. Forest Service operation. Data from 1853 flights and seven aircraft are presented. Spectra are shown for gust and maneuver loads, separated using the two-second rule. These are given for the entire flight for various mean sea-level altitudes. In addition, the combined loads are presented and compared to existing data and Federal Aviation Regulation 23. It is shown that these aircraft are operated well within their design envelope. It is demonstrated that, although gust loads are comparable to those outlined in Federal Aviation Regulation 23, the maneuver load frequencies far exceed those of typical airframe use. Although these results do not warrant changes to Federal Aviation Regulation 23, they ...

The primary objective in military aviation is to optimize operational readiness: the capability to perform assigned flight missions. In terms of a flight planning process, operational readiness has three primary components: availability, serviceability and sustainability. Furthermore, it is influenced by aircraft downtime due to preventive maintenance at prescribed flight time interval. In practice, aircraft flight scheduling (including maintenance constraints) tends to be managed manually and on a day-to-day basis, leading to a reactive approach to aircraft flight hour allocation in which problems with respect to availability, serviceability and sustainability can easily develop. Optimization models have been developed to address this issue, but none of them cover the full scope of operational readiness. This work introduces a flight and maintenance planning optimization model that simultaneously addresses the aspects of availability, serviceability and sustainability, leading to a pro-active, efficient and more robust scheduling effort. The proposed model is tested, verified and validated using Royal Netherlands Air Force data and infrastructure related to the CH47D Chinook helicopter fleet.

The Federal Aviation Administration (FAA) and European Aviation Safety Agency (EASA) have recently established new light aircraft certification rules that introduce significant changes to the current regulations. The changes include moving from prescriptive design requirements to performance-based standards, transferring many of the acceptable means of compliance out of the rules and into consensus standards. In addition, the FAA/EASA rules change the performance requirements associated with some of the more salient safety issues regarding light aircraft. One significant change is the elimination of spin recovery demonstration. The new rules now call for enhanced stall warning and aircraft handling characteristics that demonstrate resistance to inadvertent departure from controlled flight. The means of compliance with these changes in a safe, cost-effective manner is a challenging problem. This paper discusses existing approaches to reducing the likelihood of departure from controlled flight and introduces a new approach, dubbed Departure Aversion, which allows applicants to tailor the amount of departure resistance, stall warning, and enhanced safety equipment to meet the new proposed rules. The Departure Aversion approach gives applicants the freedom to select the most cost-effective portfolio for their design, while meeting the safety intent of the new rules, by ensuring that any combination of the selected approaches will be at a higher equivalent level of safety than today's status quo.

The NASA Aeronautics Research Mission Directorate (ARMD) Strategic Implementation Plan details an ambitious plan for aeronautical research for the next quarter century and beyond. It includes a number of advanced technologies needed to address requirements of the overall aviation community (domestic and international), with an emphasis on safety, efficiency, operational flexibility, and alternative propulsion air transport options. The six ARMD Strategic Thrust Areas (STAs) represent a specific set of multi-decade research agendas for creating the global aviation improvements most in demand by the aviation service consumers and the general public. To provide NASA with a measurement of the preeminent value of these research areas, it was necessary to identify and quantify the measurable benefits to the aviation community from capabilities delivered by the research programs. This paper will describe the processes used and the conclusions reached in defining the principal metrics for ARMD Strategic Thrust Area 3B "Vertical Lift Strategic Direction."

This paper presents the research of noise level monitoring at the Zagreb Airport Ltd. The purpose of this paper is to show how the aircraft noise sources can be used as a tool for aircraft detection and for increasing flight safety. The noise measurement was made at the Zagreb Airport by using its professional noise monitoring system. The research has led to new findings, such as determining the aircraft model by measuring the noise level generated by an aircraft during final approach based on its frequency spectrum, as the connectivity from the airport’s side to the radar data was unavailable (only ATC). In addition, it is possible to determine the aircraft altitude and, perhaps most significantly, the increase of flight safety through the detection of potential failures on the aircraft structure and/or engine during the overflight of a noise monitoring terminal.

Many efforts to mitigate the environmental impact of aviation, like NASA’s Subsonic Fixed Wing Project, place high importance on reducing fuel burn, nitrogen oxide (NOX) emissions, and noise of future aircraft. However, the environmental and economic impact of a new aircraft is not solely a function of the aircraft’s performance but also of how airlines use new aircraft along with other existing aircraft to satisfy the passenger demand for air transportation. In this work, an optimization problem finds the optimal allocation of existing and future aircraft to routes representing commercial air transportation within or to/from the United States to measure various fleet-level metrics. Examining fleet-level environmental metrics helps assess how aircraft meeting NASA’s Subsonic Fixed Wing Project goals could impact fleet-level environmental goals established by the International Air Transport Association. The goal set forth by the International Air Transport Association examined in this paper is to reduce to...

Analysis of data from 1,007 U.K. general aviation (GA) accidents demonstrates the predominant cause of accidents is loss of control, exacerbated by a lack of recent flying experience. These are long-standing problems that can be targeted effectively with simulation training. Discussion on training strategies in commercial aviation reinforces the logic of introducing simulation training for the GA pilot. Conclusions drawn affirm the notion that GA safety would benefit from implementation of regulated simulation training.

Flight Operations Quality Assurance or FOQA is a proven tool in the effort to enhance aviation safety. Employed by air carriers as early as the 1960’s, FOQA allows aviation operations and safety managers to objectively monitor how their aircraft are being operated. This data can then be translated into informed decisions to improve the safety and efficiency of the overall operation. While FOQA has proven itself in the world of airlines and other commercial aviation ventures, these flight data monitoring programs have largely been absent in the area where the vast majority of flight operations occur, general aviation. Advancements in technology allow those in general aviation management positions the ability to apply the same techniques in general aviation. This study attempts to further the body of knowledge of Flight Operations Quality Assurance (FOQA) programs by examining the unique requirements of a FOQA program adapted to the university flight-training environment. The methodology employed are qualitative in nature employing a Delphi study to gather data from a group of subject matter experts on both FOQA and general aviation flight instruction. Qualitative observations gathered by the researcher from the direct observation of flight instruction will be used to supplement the data gathered from the Delphi Study. Through the analysis of these two data sets, this study determines what events and parameters should be monitored in a collegiate FOQA program.

Global aviation is growing exponentially and there is a great emphasis on trajectory optimization to reduce the overall environmental impact caused by aircraft. Many optimization techniques exist and are being studied for this purpose. The CLEAN SKY Joint Technology Initiative for aeronautics and Air transport, a European research activity run under the Seventh Framework program, is a collaborative initiative involving industry, research organizations and academia to introduce novel technologies to improve the environmental impact of aviation. As part of the overall research activities, "green" aircraft trajectories are addressed in the Systems for Green Operations (SGO) Integrated Technology Demonstrator. This paper studies the impact of large commercial aircraft trajectories optimized for different objectives applied to the on board systems. It establishes integrated systems models for both conventional and more electric secondary power systems and studies the impact of fuel, noise, time and emissions optimized trajectories on each configuration. It shows the significant change in the fuel burn due to systems operation and builds up the case as to why a detailed aircraft systems model is required within the optimization loop. Typically, the objective in trajectory optimization is to improve the mission performance of an aircraft or reduce the environmental impact. Hence parameters such as time, fuel burn, emissions and noise are key optimization objectives. In most instances, trajectory optimization is achieved by using models that represent such parameters. For example aircraft dynamics models to describe the flight performance, engine models to calculate the fuel burn, emissions and noise impact, etc. Such techniques have proved to achieve the necessary level of accuracy in trajectory optimization. This research enhances previous techniques by adding in the effect of systems power in the optimization process. A comparison is also made between conventional power systems and more electric architectures. In the conventional architecture, the environmental control system and the ice protection system are powered by engine bleed air while actuators and electrics are powered by engine shaft power off-takes. In the more electric architecture, bleed off take is eliminated and the environmental control system and ice protection system are also powered electrically through engine shaft power off takes.

The Green Flight Challenge occurred in September 2011 as a competition to spur extreme flight efficiency for general aviation aircraft. In order to compete, an aircraft had to demonstrate flight over a 200 mile course at an average groundspeed of 100 mph with a fuel efficiency greater than 200 passenger miles per equivalent gallon. This paper describes the design of Taurus G4, the world’s first four-seat electric-powered aircraft, and the flight-planning techniques used in winning the competition. The aircraft demonstrated flight over a 196 mile course at an average speed of 107 mph and an average equivalent fuel efficiency of 403.5 passenger miles per equivalent gallon of automotive gasoline. In this demonstration, it showed that battery-powered flight is practical for general aviation missions.

Rapidly expanding unmanned air traffic includes and will continue to include non-cooperative participants. Non-cooperative behavior may be due to technical failure, a lack of appropriate equipment, a careless or malicious operator. Regardless of the cause, the outcome remains: growing density of non-cooperative traffic will increase the risk of collision between unmanned vehicles and aircraft carrying humans. As a result, the degraded safety of airspace may limit access to airspace, with adverse consequences for the traveling public and the economy. Because encounters with small non-cooperative objects, such as birds or wayward drones, can happen too rapidly for an external control system to mitigate them, it is imperative that the aircraft that carry humans survive encounters with non-cooperative vehicles. To-date, design for survivability has been practiced explicitly in the military domain. Survivability against collisions in civil aviation has been limited to tolerances against bird strikes; and these tolerances have proved inadequate on occasion. The growing risk of collision with unmanned vehicles now requires the development of survivability discipline for civilian transport aircraft. The new discipline must be infused into multidisciplinary design methods, on par with traditional disciplines. In this paper, we report on a preliminary study of survivability considerations for the civil aviation domain.

gross weight, acquisition cost, and operating cost) based on design requirements derived from market research and the perceived needs of aircraft operators. This is a loosecoupling between the aircraft design problem of the aircraft manufacturer and the assignment or allocation problem of the aircraft operator. Providing a tighter coupling between aircraft operations and aircraft design can concurrently identify the best new aircraft design and the best operational concept using this new aircraft. This paper presents an approach to couple the uncertain aircraft assignmentproblemoffractionaloperationsandtheaircraftdesignproblemofaircraftmanufacturers.Asolutionto thistypeofproblemdescribesanaircraftdesignthatdirectlyimprovesoperationsandidentifiesoperatingstrategies that influence, and take advantage of, the characteristics of the new aircraft. With this formulation, an aircraft manufacturer could work more closely with a customer to determine the best new aircraft for the operations.

The subject of investigation are unmanned aircraft lighter than 150kg under control by national aviation authorities and therefore prudently requiring harmonized individual state regulations. Originated from a general premise that the unmanned aircraft regulations should evolve from the existing standards for manned aircraft of equivalent class or category, the light fixed wing unmanned aircraft equivalence to the manned aircraft is defined in the form of sets of equivalency and non-equivalency based on the established administrative type of methodology of impact kinetic energy comparison. The basic flight characteristics of the existing operational light fixed wing unmanned aircraft are analyzed assuring proper input for determination of the more realistic unmanned aircraft impact kinetic energy in controlled and uncontrolled flight into terrain crash scenarios used for the evaluation of established methodology adequacy for equivalence determination. It is shown in the paper that determination of the unmanned aircraft equivalency to the manned aircraft should not be based on the unmanned aircraft maximum take-off mass nor their airspeed range alone. KEYWORDS: light unmanned aircraft, impact kinetic energy, hazard potential, classification

This paper describes calculations and computer simulations concerning handling qualities of general aviation aircraft equipped with an indirect (fly-by-wire) control system. The main idea of this proposal is shaping small aircraft dynamic characteristics in a way that enables all general aviation aircraft to exhibit similar user-friendly properties from the pilot’s point of view. The natural solution of this problem is modifying aircraft dynamic properties to comply with the “ideal model” of a safe and easily controllable airplane. We can improve the handling qualities of an aircraft using the indirect flight control system. In this paper, the model following method was used for controller synthesis, with the purpose of obtaining qualitatively new handling properties and simplifying the control system for pilots with limited professional training. However, a control system designer has to assume responsibility for proper functioning of complex flight control systems. The properties of the optimal controll...

Safety of Operation and Maintenance Systems of Aircraft Fleet The flight of on aircraft has been realzed I on operational subsystem. The operation of on aircraft and its safeability are determined for aircraft fleet the so-called flight safety. Aircraft operation and its safeability determine the flight safety of aircraft fleet. The flight safety can be modelled, condition diagnosed, put the procedures of genesis and prognosis. As the results of these activities the prevention treatments can be worked out. A aircraft safety, air system safety or air safety can be considered. Within the flight safety science.

Poznavanje stvarnih performansi zrakoplova bitno je za učinkovitu eksploataciju i pravovremeno održavanje. Performanse su određene fizikalnim karakteristikama zrakoplova. U Priručniku za letenje opisane su teorijske performanse određene od proizvođača nakon proizvodnje zrakoplova i testiranja u letu. Komercijalni zrakoplovi su tijekom svog operativnog ciklusa uglavnom izloženi predviđenim uvjetima eksploatacije. Unatoč predviđenim uvjetima eksploatacije i redovnom održavanju, starenje materijala i velika opterećenja na strukturu zrakoplova kod leta visokim podzvučnim Machovim brojem, mogu dovesti do promjene temeljnih fizikalnih faktora koji određuju performanse. Zbog toga se stvarne performanse zrakoplova nerijetko razlikuju od teorijskih. Zračni prijevoznici prate stanje zrakoplova i njegove stvarne performanse tijekom korištenja. U ovom radu prikazan je pregled dosadašnjih metoda praćenja performansi i mogućnosti istraživanja na području određivanja fizikalnih parametara zrakoplova u eksploataciji prema podacima iz leta., To ensure timely maintenance and efficient aircraft operations, it is necessary to know and keep track of aircraft’s actual performance. Flight performance is determined by aircraft's physical characteristics. Theoretical aircraft performance, obtained after manufacturing and flight testing, are described in flight manual. Transport aircraft in operation is usually exposed to standard operational conditions. Despite the standard operational conditions and regular aircraft maintenance, structure aging and high dynamic loads due to high subsonic Mach number could lead to changes of main physical factors that determine flight performance. For this reason actual aircraft performance often differs from theoretical. Commercial airlines monitor true performance of aircraft in operation. This paper presents an overview of existing performance monitoring methods as well as first indications for new research possibilities regarding physical characteristics determination for aircraft in operation using flight data.

General aviation (14CFR Part 91) accounts for 83% of civil aviation fatalities. While much research has focused on accident causes/pilot demographics in this aviation sector, studies to identify factors leading up to the crash (accident-precipitating factors) are few. Such information could inform on pre-emptive remedial action. With this in mind and considering the paucity of research on turbine-powered aircraft accidents the study objectives were to identify accident-precipitating factors and determine if the accident rate has changed over time for such aircraft operating under 14CFR Part 91. The NTSB Access database was queried for accidents in airplanes (

Aircraft enthusiasts who desire to build and fly their own aircraft are 350% more likely to be involved in an accident during the first 40 hours of flight than all other aircraft in the general aviation (GA) fleet. Pilots must manually collect measurements that are used to develop a pilot’s operating handbook (POH), to include emergency procedures. Currently, no system exists to automate the process of recording specific inflight aircraft measurements, parameterizing the aircraft, and creating the necessary documentation required by the FAA. This project proposes a low-cost flight data recording and analysis system that uses a combination of hardware and software for experimental amateur built (E-AB) aircraft pilots to use during the first 40 hours of their testing process that will help reduce error and inconsistencies. Final simulation data will be used to influence the ultimate device requirements for both the microcontroller platform, and inertial and positional sensors.

Despite the NASA X-15 program’s outstanding success in developing and operating the first manned hypersonic research platform, the program suffered a fatal accident on November 15, 1967, when X-15-3, the only aircraft outfitted with advanced pilot displays and an adaptive flight control system, was lost after entering uncontrolled flight at an altitude of 230,000 feet and a velocity near Mach 5. The pilot, Major Michael J. Adams, was incapacitated by the aircraft accelerations and was killed either during the ensuing breakup or upon ground impact.

In this paper, passengers evaluation to air transport service with small aircraft is analyzed. At first, passengers images to specific aircraft such as large jet aircraft, small jet aircraft, and small turbo-prop aircraft were compared. Then it was shown that small turbo-prop aircraft is especially evaluated as a lesser safety aircraft. Secondly, air transport service choice models were estimated, and the existence of negative effects of the service with small aircraft and with propeller aircraft was shown. Finally, sensitivity analysis was executed, and it was clear that the negative image of the turbo-prop aircraft can be supplemented with lower fare.

Future very large transport aircraft (VLTA) represents an exciting and important development in civil aviation. The emergency evacuation of VLTAs in the event of a survivable crash poses a challenge for aircraft manufacturers and certification authorities. The information which has been gained from previous evacuation research has been re‐evaluated for VLTA. This included consideration of the aircraft configuration, crew factors and passenger issues.

The main goal of the presented project is to improve safety and Handling Qualities of general aviation aircraft so that airplane becomes pilot-friendly, “almost unmanned” aircraft. In this paper, a proposal of employing an intuitive, human-centered, simplified software-based flight control system in general aviation aircraft has been presented. Airplanes equipped with such a flight control system belong to a new class of general aviation aircraft with improved safety and efficiency handling properties – Facilitated Airplane (FA) or Simple Flying Airplane (SFA). The basic idea of the project is to employ an indirect (Fly-by-Wire) software-based flight control system characterized by high degree of automatization, leading to an almost “unmanned” general aviation aircraft. “Unmanned” does not mean eliminating humans from the control process but changing their role in the system. User-friendly control system should shape handling qualities of an aircraft in such a way that control becomes easy and safe. Pilot retains the crucial role of decision-maker, and control system takes appropriate steps to fulfill his requirements, or suggests optimal methods of implementing his decisions. Such a system may be considered to be pilot's electronic assistant as it integrates simplified handling flight controls and autopilot functions, and reduces the complexity of interactions between aircraft attitudes, power settings, and rate of motion, and in conclusion limits the possibility of loss of control.

Boeing Co. and NASA have joined forces for the Active Aeroelastic Wing (AAW) Project to test the way a modified F/A-18 strike fighter uses its wings. The AAW was designed to be flexible enough to be twisted on demand in flight and it could herald nothing less than a revolution in aviation. The twisting can be used to control the plane's roll, reducing and ultimately eliminating the need for ailerons and flaps and their associated hardware. AAW-equipped planes would result to increased fuel efficiency and improved maneuverability, able to execute sharper turns at higher speeds. A special flight software was developed to keep track of the plane's speed, altitude, and attitude while monitoring the pilot's controls for commands. Based on a set of rules known as control laws, the software must then translate any commands from the pilot into movements of the aircraft's various control surfaces such as the rudders or, most significantly, the flaps that flex the AAWs. Despite its complex and critical job, the flight software is compact, consisting of only about 13,000 lines of source code written in the Ada language.

Army Aviation utilizes two distinct types of overhaul maintenance schedules on its rotary wing aircraft, Phase Maintenance and Progressive Phase Maintenance. All but one aircraft, the OH-58D Kiowa Warrior, use Phase Maintenance. This aircraft has both the highest operational readiness rate and average flight hours in the Army's rotary wing fleet. The Army values uniformity in maintenance procedures across its fleets; however this inconsistency has existed for two decades. This study models the value and tradeoffs of one method versus the other using discrete event simulation. Progressive Phase Maintenance offers more efficiency in terms of time available for missions and may be applicable other airframes. Using the airframe specific Aeronautical Equipment Maintenance Management Policies and Procedures Training Manual and a operational data set from a deployed aviation unit, this study compares the two overhaul maintenance schedules in terms of operational readiness. The effectiveness of each method is measured in the amount of time each airframe is for missions.

Flight simulation had played a very important role in aerospace and aviation industries as an engineering tool and training equipment. Computers provided the capability of stimulating an aircraft in flight without actually flying the aircraft, thus providing safety to pilots and also cost reduction in pilot training and aircraft design. Aerodynamic characteristics were modelled mathematically to display the air craft orientation and the aircraft motion during manoeuvres. Implementation of aerodynamic database system enables a flight simulator to stmulate many types of aircraft manoeuvres.

This paper presents the development and implementation of a novel Flight Management System (FMS) to ensure onboard passenger safety of commercial aircraft in the event of an emergency scenario where the pilot must relinquish control of the aircraft (e.g. hijacking or loss of cabin pressure). In such situations, the flight management system autonomously pilots the aircraft to a predefined destination whilst taking into account potential hazards such as terrain (in low altitude scenarios), aircraft dynamic constraints, and flight objectives with real-time constraints present. Furthermore, the FMS must ensure that the Human Decision Maker (HDM) (e.g. Air Traffic Control or ATC) has sufficient time to intervene if they do not agree with automated onboard decisions. The proposed FMS shows that the inclusion of intelligent planning capabilities onboard commercial aircraft can assist in improving safety for the aircraft and onboard passengers in the event of emergencies by allowing the aircraft to continue operating autonomously in a management by exception paradigm. This approach has been demonstrated in this paper through simulation using a commercial aircraft model operating in low altitude partially known environments.

Game changing advances come about by the introduction of new technologies at a time when societal needs create the opportunity for new market solutions. A unique opportunity exists for NASA to bring about such a mobility revolution in General Aviation, extendable to other aviation markets, to maintain leadership in aviation by the United States. This report outlines the research carried out so far under NASA's leadership towards developing a new mobility choice, called Zip Aviation1,2,3. The feasibility, technology and system gaps that need to be addressed, and pathways for successful implementation have been investigated to guide future investment. The past decade indicates exciting trends in transportation technologies, which are quickly evolving. Automobiles are embracing automation to ease driver tasks as well as to completely control the vehicle with added safety (Figure 1). Electric propulsion is providing zero tail-pipe emission vehicles with dramatically lower energy and maintenance costs. These technologies have not yet been applied to aviation, yet offer compelling potential benefits across all aviation markets, and in particular to General Aviation (GA) as an early adopter market. The benefits of such an adoption are applicable in the following areas: 􀁸 Safety: The GA market experiences accident rates that are substantially higher than automobiles or commercial airlines, with 7.5 fatal accidents per 100 million vehicle miles compared to 1.3 for automobiles and.068 for airlines. Approximately 80% of these accidents are caused by some form of pilot error, with another 13% caused by single point propulsion system failure. 􀁸 Emissions: Environmental constraints are pushing for the elimination of 100Low Lead (LL) fuel used in most GA aircraft, with aviation fuel the #1 source of lead emissions into the environment. Aircraft also have no emission control systems (i.e. no catalytic converters etc.), so they are gross hydrocarbon polluters compared to automobiles. 􀁸 Community Noise: Hub and smaller GA airports are facing increasing noise restrictions, and while commercial airliners have dramatically decreased their community noise footprint over the past 30 years, GA aircraft noise has essentially remained same, and moreover, is located in closer proximity to neighborhoods and businesses. 􀁸 Operating Costs: GA operating costs have risen dramatically due to average fuel costs of over $6 per gallon, which has constrained the market over the past decade and resulted in more than 50% lower sales and 35% less yearly operations. Infusion of autonomy and electric propulsion technologies can accomplish not only a transformation of the GA market, but also provide a technology enablement bridge for both larger aircraft and the emerging civil Unmanned Aerial Systems (UAS) markets. The NASA Advanced General Aviation Transport Experiments (AGATE) project successfully used a similar approach to enable the introduction of primary composite structures and flat panel displays in the 1990s, establishing both the technology and certification standardization to permit quick adoption through partnerships with industry, academia, and the Federal Aviation Administration (FAA). Regional and airliner markets are experiencing constant pressure to achieve decreasing levels of community emissions and noise, while lowering operating costs and improving safety. But to what degree can these new technology frontiers impact aircraft safety, the environment, operations, cost, and performance? Are the benefits transformational enough to fundamentally alter aircraft competiveness and productivity to permit much greater aviation use for high speed and On-Demand Mobility (ODM)? These questions were asked in a Zip aviation system study named after the Zip Car, an emerging car-sharing business model. Zip Aviation investigates the potential to enable new emergent markets for aviation that offer "more flexibility than the existing transportation solutions." These studies indicate that autonomy and electric propulsion technology infusions offer a unique opportunity to provide breakthrough capabilities for new high speed, on-demand travel alternatives that can leapfrog the need for future expensive ground-based infrastructure investment. At the same time, such investments offer a method of laying the foundation for these technologies to be incubated for commercial aviation at lower cost, and with lower initial certification thresholds due to the relatively poor capabilities of GA aircraft to permit early adoption and private market capitalization by rapid technology accelerations, as depicted in Figure 2.

In 2006 an accident occurred when a Cessna 152 training aircraft was carrying out a training flight. After taking off, the aircraft engine started to work sporadically as the aircraft gained altitude, and then it stopped. The aircraft crashed. During the crash, the aircraft was damaged and set on fire. Two people, the pilot-instructor and the trainee-pilot perished in the catastrophe. Aircraft of this type are not equipped with flight data recorders. As a result, it is a problem to objectively get information about the cause of the aircraft accident. With consideration of the available information (the investigation report and aircraft operating manual), the current paper contains the following: the pilot-instructor's possible operational analysis when preparing for the flight, the schemes of possible flight directions and trajectories in the situation, the scenarios of the operations the pilot could have made and the possible motion of the aircraft, the estimates that were conducted, and judgement of the pilot-instructor's operations during the accident according to the requirements of operational standards. First published online: 01 Jul 2013

The rapid increase in aviation industry requires parallel effective plans, programs and designs of systems and facilities nationwide to fulfill the increasing needs for safe air transportation. Aircraft landing remains a problem for a long time all over the world. Systems that aircraft rely on in landing are unreliable to perform a precise guidance due to many limitations such as inaccuracy, unreliability and dependency. In low visibility conditions, aircrafts are diverted to another airport. However, low visibility can also affect all airports in the vicinity, forcing aircrafts to land in low visibility conditions depending on Instrument Flight Rules (IFR). Aircraft approach and landing are the most hazardous portions of flight; accidents records indicated that approximately 50 percent of the accidents occur during these portions. Aircraft landing Category IIIC is not yet in operation anywhere in the world. It requires landing with no visibility or runway visual range. Currently, Global Positioning System (GPS) is the main navigation system used all over the world for aircraft navigation, approach and landing. However, GPS accuracy is not sufficient to perform a perfect landing due to the possibility of aircraft to be drifted out of the runway. The accuracy of GPS could be improved to 3 meter by receiving correction messages. Improved accuracy has not been able to meet International Civil Aviation Organization (ICAO) standards for aircraft precision landing. In this study, aircraft landing systems characteristics, performances and accuracies have been studied and compared for the purpose of assessing limitations and drawbacks. An aircraft landing system with improved performance is proposed to meet ICAO standards for all-weather aircraft landing and to provide accurate guidance for approaching and landing aircrafts.

Flight delays and safety are the principal contradictions in the sound development of civil aviation. Flight delays often come up and induce civil aviation safety risk simultaneously. Based on flight delays, the random characteristics of civil aviation safety risk are analyzed. Flight delays have been deemed to a potential safety hazard. The change rules and characteristics of civil aviation safety risk based on flight delays have been analyzed. Bayesian networks (BN) have been used to build the aviation operation safety assessment model based on flight delay. The structure and parameters learning of the model have been researched. By using BN model, some airline in China has been selected to assess safety risk of civil aviation. The civil aviation safety risk of BN model has been assessed by GeNIe software. The research results show that flight delay, which increases the safety risk of civil aviation, can be seen as incremental safety risk. The effectiveness and correctness of the model have been tested and verified.

Militarized versions of commercial platforms are growing in popularity due to many logistical benefits in the form of commercial off-the-shelf (COTS) parts, established production methods, and commonality for different certifications. Commercial data and best practices are often leveraged to reduce procurement and engineering development costs. While the developmental and cost reduction benefits are clear, these militarized aircraft are routinely operated in flight at significantly different conditions and in significantly different manners than for routine commercial flight. Therefore they are at a higher risk of flight envelope exceedance. This risk may lead to departure from controlled flight and/or aircraft loss1. Historically, the risk of departure from controlled flight for military aircraft has been mitigated by piloted simulation training and engineering analysis of typical aircraft response. High-agility military aircraft simulation databases are typically developed to include high angles of attack (AoA) and sideslip due to the dynamic nature of their missions and have been developed for many tactical configurations over the previous decades. These aircraft simulations allow for a more thorough understanding of the vehicle flight dynamics characteristics at high AoA and sideslip. In recent years, government sponsored research on transport airplane aerodynamic characteristics at high angles of attack has produced a growing understanding of stall/post-stall behavior. This research along with recent commercial airline training initiatives has resulted in improved understanding of simulator-based training requirements and simulator model fidelity.2-5 In addition, inflight training research over the past decade has produced a database of pilot performance and recurrency metrics6. Innovative solutions to aerodynamically model large commercial aircraft for upset conditions such as high AoA, high sideslip, and ballistic damage, as well as capability to accurately account for scaling factors, is necessary to develop realistic engineering and training simulations. Such simulations should significantly reduce the risk of departure from controlled flight, loss of aircraft, and ease the airworthiness certification process. The characteristics of commercial derivative aircraft are exemplified by the P-8A Multi-mission Maritime Aircraft (MMA) aircraft, and the largest benefits of initial investigation are likely to be yielded from this platform. The database produced would also be utilized by flight dynamics engineers as a means to further develop and investigate vehicle flight characteristics as mission tactics evolve through the years ahead. This paper will describe ongoing efforts by the U.S. Navy to develop a methodology for simulation and training for large commercial-derived transport aircraft at unusual attitudes, typically experienced during an aircraft upset. This methodology will be applied to a representative Navy aircraft (P-8A) and utilized to develop a robust simulation that should accurately represent aircraft response in these extremes. Simulation capabilities would then extend to flight dynamics analysis and simulation, as well as potential training applications. Recent evaluations of integrated academic, ground-based simulation, and in-flight upset training will be described along with important lessons learned, specific to military requirements.

Loss of control (LOC) remains one of the largest contributors to aircraft fatal accidents worldwide. Aircraft LOC accidents are highly complex in that they can result from numerous causal and contributing factors acting alone or more often in combination. Hence, there is no single intervention strategy to prevent these accidents. Research is underway at the National Aeronautics and Space Administration (NASA) in the development of advanced onboard system technologies for preventing or recovering from loss of vehicle control and for assuring safe operation under off-nominal conditions associated with aircraft LOC accidents. The transition of these technologies into the commercial fleet will require their extensive validation and verification (V&V) and ultimate certification. The V&V of complex integrated systems poses highly significant technical challenges and is the subject of a parallel research effort at NASA. This chapter summarizes the V&V problem and presents a proposed process that could be applied to complex integrated safety-critical systems developed for preventing aircraft LOC accidents. A summary of recent research accomplishments in this effort is referenced.

This paper presents a conception of an airborne control system that can increase the safety of a general aviation aircraft. Sample threats appear on board the general aviation airplane discussed in the paper. The system monitors some events and flight parameters in the cockpit and can take some actions protecting the plane against threats if recognised as necessary. The paper presents sample actions fly‐by‐wire control systems can take to protect a plane against some threats on board. The system can modify a pilot's controls to correct flight and if it is not enough the system can disengage the pilot to autonomously fly the plane to the nearest safe airport Skrydžių saugumą padidinančios sistemos idėja Santrauka.Straipsnyje pateikta valdymo iš oro sistemos koncepcija, kuri gali padidinti bendrosios aviacijos orlaivių saugumą bei aptartos pavyzdines grėsmės bendrosios aviacijos orlaiviuose. Aprašoma sistema stebi lakūno kabinoje rodomus įvairius skrydžio parametrus ir, kilus bet kokiai grėsmei orlaivio saugumui, gali jį apsaugoti. Darbe pateikiami ir kompiuterizuoto elektrodistancinio valdymo sistemos pavyzdžiai, kurie taip pat gali apsaugoti orlaivį nuo jam kylančių grėsmių. Ši sistema gali modifikuoti piloto valdymą taip, kad būtų pakoreguotas skrydis, o jei ir to neužtenka – sistema pajėgi ir autonominiam skrydžiui, kuomet orlaivis yra nukreipiamas į artimiausią ir saugiausią oro uostą be piloto pagalbos. Reikšminiai žodžiai: bendroji aviacija,skrydžių saugumas,automatinis skrydis. First publish online: 10 Feb 2011

Throughout the 20th Century, NASA has defined the forefront of aeronautical technology, and the aviation industry owes much of its prosperity to this knowledge and technology. In recent decades, centralized aeronautics has become a mature discipline, which raises questions concerning the future aviation innovation frontiers. Three transformational aviation capabilities, bounded together by the development of a Free Flight airspace management system, have the potential to transform 21st Century society as profoundly as civil aviation transformed the 20th Century. These mobility breakthroughs will re-establish environmental sustainable centralized aviation, while opening up latent markets for civil distributed sensing and on-demand rural and regional transportation. Of these three transformations, on-demand aviation has the potential to have the largest market and productivity improvement to society. The information system revolution over the past 20 years shows that vehicles lead, and the interconnecting infrastructure to make them more effective follows; that is, unless on-demand aircraft are pioneered, a distributed Air Traffic Control system will likely never be established. There is no single technology long-pole that will enable on-demand vehicle solutions. However, fully digital aircraft that include electric propulsion has the potential to be a multi-disciplinary initiator of solid state technologies that can provide order of magnitude improvements in the ease of use, safety/reliability, community and environmental friendliness, and affordability.

Inverse problems can be applied to aircraft in many areas. One of the disciplines within the aerospace industry with the most openly published data is in the area of aircraft performance. Many aircraft manufacturers publish performance claims, flight manuals and Standard Aircraft Characteristic (SAC) charts without any mention of the more fundamental technical information such as CD0 . With accurate tools, generalized aircraft models and a few curve-fitting techniques, it is possible to evaluate vehicle performance and estimate these technical parameters. With this goal a program has been written in Matlab to calculate the fundamental information behind a general aircraft. The current results are promising with more work underway to further improve them. The results shown are for the Northrop F-5. While the results look good, the overall accuracy of the program is only as good as the data provided. For example, the maximum speed reported by a company may assume that the aircraft is in a dive with engines at full throttle. Or, the measurements may be overly optimistic, with an important characteristic such as ground friction during takeoff left out of the picture. If this information is not reported then an accurate analysis is not possible. Nomenclature

A modified T210R general aviation aircraft incorporating natural laminar flow (NLF) technology has been subjected to flight tests in order to evaluate its stability and control characteristics. Attention is given to this aircraft's ability to meet certification requirements with significant NLF, as well as with the boundary-layer transition fixed near the leading edge. It is established that the large regions of NLF achieved yielded a significant cruise performance enhancement; loss of laminar flow did not result in significant changes in the stability and control characteristics of the aircraft. FAR Part 23 certification requirements were met.

During the past five years, the U.S. Federal Aviation Regulations (FARs) have been significantly modified with respect to strength of seats and restraint systems, their attachments to the aircraft structure, and the means for their evaluation. Aircraft accident data, human tolerance levels, and aircraft structural characteristics have been considered in developing the new standards, which require dynamic testing of seats and restraint systems. FAR Part 23, which deals with small airplanes, was first amended to require dynamic testing of seats and restraint systems for normal and utility (general aviation) aircraft with capacity for fewer than 10 passengers. Performance criteria are similar to those specified by the U.S. Federal Motor Vehicle Safety Standards for automobiles, but also include a limit on pelvic force in order to prevent spinal injuries that may be caused by the vertical component of impact force. Similar regulatory actions, although requiring somewhat different dynamic test conditions, have also been implemented for transport aircraft, which are covered by FAR Part 25, and for helicopters, under FAR Parts 27 and 29. Commuter-type aircraft have not been affected by the FAR modifications. Commuter types seat 10 to 19 passengers, are closer in size to general aviation aircraft than to large transports, and are also covered by FAR Part 23. The Federal Aviation Administration (FAA) is currently involved in a research program that includes full-scale aircraft drop tests, sled tests of seats, and computer simulations that should lead to a proposal for amendment of the regulations for commuter-type aircraft. The objectives of this paper are to describe the research program and to document some conclusions that may be drawn from its results concerning seat and restraint system design, dynamic testing, and acceptance criteria.

Over the past decade, the goal of reducing the fatal accident rate of large transport aircraft has resulted in research aimed at the problem of aircraft loss-of-control. Starting in 1999, the NASA Aviation Safety Program initiated research that included vehicle dynamics modeling, system health monitoring, and reconfigurable control systems focused on flight regimes beyond the normal flight envelope. In recent years, there has been an increased emphasis on adaptive control technologies for recovery from control upsets or failures including damage scenarios. As part of these efforts, NASA has developed the Airborne Subscale Transport Aircraft Research (AirSTAR) flight facility to allow flight research and validation, and system testing for flight regimes that are considered too risky for full-scale manned transport airplane testing. The AirSTAR facility utilizes dynamically-scaled vehicles that enable the application of subscale flight test results to full scale vehicles. This paper describes the modeling and simulation approach used for AirSTAR vehicles that supports the goals of efficient, low-cost and safe flight research in abnormal flight conditions. Modeling of aerodynamics, controls, and propulsion will be discussed as well as the application of simulation to flight control system development, test planning, risk mitigation, and flight research.

The purpose of this study was to analyze the frequency of general aviation (GA) airplane accidents and accident rates on the basis of aircraft certification to determine whether or not differences in aircraft certification rules had an influence on accidents. In addition, the narrative cause descriptions contained within the accident reports were analyzed to determine whether there were differences in the qualitative data for the different certification categories. The certification categories examined were: Federal Aviation Regulations Part 23 (Part 23), Civil Air Regulations 3 (CAR 3), Light Sport Aircraft (LSA), and Experimental-Amateur Built (E-AB). The accident causes examined were those classified as: Loss of Control (LOC), Controlled Flight into Terrain (CFIT), Engine Failure, and Structural Failure. Airworthiness certification categories represent a wide diversity of government oversight. Part 23 rules have evolved from the initial set of simpler design standards and have progressed into a comprehensive and strict set of rules to address the safety issues of the more complex airplanes within the category. E-AB airplanes have the least amount of government oversight and are the fastest-growing segment. The LSA category is a more recent certification category that utilizes consensus standards in the approval process. CAR 3 airplanes were designed and manufactured under simpler rules, but modifying these airplanes has become lengthy and expensive. The study was conducted using a mixed-methods methodology. A Chi-Square test was used for a quantitative analysis of the accident frequency among aircraft certification categories. Accident rate analysis of the accidents among aircraft certification categories involved an This article is based on the Doctoral Dissertation of Carolina L. Anderson, submitted to the Department of Doctoral Studies in partial fulfillment of the requirements for the degree of Doctor of Philosophy at Embry-Riddle Aeronautical University. About the Author Carolina Anderson earned her PhD in aviation from Embry-Riddle Aeronautical University in December of 2013. The title of her dissertation was The Effects of Aircraft Certification Rules on General Aviation Accidents. Dr. Anderson holds an MBA from Embry-Riddle Aeronautical University (2002) and a BS in mechanical engineering from Los Andes University in Bogota, Colombia (1998). In addition, she holds the following professional certifications: Airline Transport Pilot Certificate; Certified Flight Instructor; Glider, Instrument and Multi-engine Ratings; Check Pilot and Training Center Evaluator (2004–2011) (Federal Aviation Administration). Dr. Anderson is an assistant professor of aeronautical science in the College of Aviation at Embry-Riddle Aeronautical University (ERAU; 2011 to present). Prior to joining the faculty at ERAU, she served as Training Manager for the Flight Department at ERAU, Standards Check-Pilot and Flight Instructor (2000–2011). Over the last five years, Dr. Anderson has been involved in numerous research projects, including the flight testing of biofuels for general aviation, the development and instruction of an Upset Recovery Training Course for FAA inspectors, the development and acquisition of flight test data for Level 6 Flight Training Devices (FTDs), as well as various projects for the FAA Center of Excellence for General Aviation Research (CGAR). Dr. Anderson participated in the Part 23 Aviation Rulemaking Committee and she is currently the vice chairman of the Industry Liaison Sub-Committee of the ASTM General Aviation Chapter (F44). Correspondence concerning this article should be sent to lenzc@erau.edu. Journal of Aviation Technology and Engineering 4:2 (2015) 32–48 http://dx.doi.org/10.7771/2159-6670.1104 analysis of covariance (ANCOVA) test. The qualitative component involved the use of text mining techniques for the analysis of the narrative cause descriptions contained within the accident reports. The Chi-Square test indicated that there was no significant difference in the number of accidents among the different certification categories when either CFIT or Structural Failure was listed as cause. However, there was a significant difference in the frequency of accidents with regard to LOC and Engine Failure accidents. The results of the ANCOVA test indicated that there was no significant difference in the accident rate with regard to LOC, CFIT, or Structural Failure accidents. There was, however, a significant difference in Engine Failure accidents between E-AB and the other categories. The text mining analysis of the narrative causes of LOC accidents indicated that only the CAR 3 category airplanes had clusters of words associated with visual flight into instrument meteorological conditions. CAR 3 airplanes were designed and manufactured prior to the 1960s, and in most cases have not been retrofitted to take advantage of newer technologies that could help prevent LOC accidents. The study indicated that GA aircraft certification rules do not have a statistically significant effect on aircraft accidents except for LOC and Engine Failure. According to the literature, government oversight could have become an obstacle in the implementation of safetyenhancing equipment that could reduce LOC accidents. Oversight should focus on ensuring that E-AB aircraft owners perform a functional test that could prevent some of the Engine Failure accidents.

The most basic solution for monitoring position and attitude of an UA is through direct line-of-sight. Because they are usually standing outside, a pilot that maintains direct line-of-sight with the aircraft is usually referred to as the EP, as opposed to an internal pilot (IP) who obtains position and attitude information electronically while inside of a ground control station (GCS). Flight using an EP represents the most basic solution to the problem of separating the pilot from the aircraft while still enabling the pilot to monitor the location and attitude of the aircraft. Pilot perspective is changed from an egocentric to an exocentric point of view. Maintaining visual contact with the UA, the EP can control the aircraft using a hand-held radio control box. Many of these control boxes are similar to those used by radio-controlled aircraft hobbyists and provide direct control of the flight surfaces of the aircraft through the use of joysticks on the box. Very little automation is involved in the use of such boxes, which control the flight surfaces of the aircraft.

The Airborne Subscale Transport Aircraft Research (AirSTAR) testbed being developed at NASA Langley Research Center is an experimental flight test capability for research experiments pertaining to dynamics modeling and control beyond the normal flight envelope. An integral part of that testbed is a 5.5% dynamically scaled, generic transport aircraft. This remotely piloted vehicle (RPV) is powered by twin turbine engines and includes a collection of sensors, actuators, navigation, and telemetry systems. The downlink for the plane includes over 70 data channels, plus video, at rates up to 250 Hz. Uplink commands for aircraft control include over 30 data channels. The dynamic scaling requirement, which includes dimensional, weight, inertial, actuator, and data rate scaling, presents distinctive challenges in both the mechanical and electrical design of the aircraft. Discussion of these requirements and their implications on the development of the aircraft along with risk mitigation strategies and training exercises are included here. Also described are the first training (non-research) flights of the airframe. Additional papers address the development of a mobile operations station and an emulation and integration laboratory.

The first major structural component failure of a composite part on a commercial airplane occurred during the crash of American Airlines Flight 587. The fractured composite lugs that attached the vertical stabilizer to the aircraft tail and the fractured composite honeycomb rudder were examined as part of the National Transportation Safety Board investigation of the accident. In this paper the composite fractures are described and the resulting clues to the failure events are discussed.