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The remarkable and continuous growth of the unmanned aircraft market has brought new safety related challenges, as those are recorded in various accident and incident reports. Although drones with an operating weight higher than 20-25Kgs are technologically advanced and often subject to standards (e.g., technical reliability, airspace management, licensing, certification), the regulatory framework for (ultra) light drones focuses almost exclusively on the limitations that the operator needs to consider. Thus, the protection from accidents seems to rely mostly on the competency of the operator to fly a drone safely, and his/her observance of the rules published by the respective authorities. In addition, the hazards lying in the interaction between an operator and a small drone have not been systematically studied. In this paper, we present (1) the first results from a System-Theoretic Process Analysis (STPA) based approach to the identification of hazards and safety requirements in small drone operations, and (2) an adaptation of the Risk Situation Awareness Provision Capability (RiskSOAP) methodology in order to quantify the differences amongst 4 drone models regarding the extent to which they fulfill the safety requirements identified through STPA. The results showed that the drones studied satisfy the safety requirements at low and moderate levels and they present high dissimilarities between them regarding the extent to which they meet the same safety requirements. Future work will include: (a) comparison of a larger sample of small drones against the safety requirements, as well as pairwise, and (b) assessment of the degree to which various regulatory frameworks worldwide address the safety requirements generated with STPA and assigned to the authority level.

In the traditional approach to Air Traffic Management, safety is treated as a main goal. Current safety management systems are constructed according to this approach. However, with the development of technical support systems, further increasing the real level of safety is difficult for operational, technical and economic reasons. We should therefore expect that in future safety will be treated as a constraint in the process of transport systems optimization instead of a goal. The paper proposes to use the cost, the air traffic smoothness or the environmental nuisance as new criteria for characterizing the quality of air traffic. This requires both new measures of the criteria proposed and a new generation of safety performance indicators allowing quantitative comparison of the level of safety for different organizational variants of the transport system. This paper presents an analysis of the problem and the proposal for such indicators. The essence of this concept is the hierarchical combination of indicators of a very general nature with specific and specialized ones.

Engineered Material Arresting System (EMAS) could be constructed in runway end safety area to arrest an overrun aircraft. EMAS bed is the main part of EMAS and consists of the EMAS material, such as foam concrete. EMAS and its design method should be verified by actual aircraft test. A large passenger jet, one main aircraft type of civil aviation should be used in actual aircraft verification test of EMAS. The jet came from an airline operation front line. To minimize the effect of the test on the jet's airworthiness, the landing gears of the jet should not be remove in the measurement system mounting. The jet's motion in EMAS could be analyzed, and the performance requirement of landing gear load measurement system could be studied. Accordingly, landing gear load measurement system and field calibration test method were presented. For the verification of measurement system, the aircraft taxi tests such as taxi brake test, engine ground run up test and a short EMAS bed test had been done with the system. Through analyzing the measured loads of the landing gears, weight of the jet and the limit load of landing gears, the system could be verified. The results show that the load measurement system could satisfy EMAS actual aircraft verification test, and the test and verification method should satisfy other large aircraft landing gear load measurement

Aviation safety relies heavily on maintenance, yet improper maintenance contributes to a significant proportion of safety threats that cause aviation accidents or incidents. In order to fully understand the maintenance errors and contributing factors, this paper investigated a sample of 3,783 Aviation Safety Reporting System (ASRS) incident reports submitted in the period of January 1st 2008 to December 31st 2008, which are formed by maintenance personnel or non-maintenance personnel. The Maintenance Error Decision Aid (MEDA) and Correspondence Analysis (CA) methods are used to analysis maintenance error, its contributing factors and the relationship between them. The result shows both maintenance personnel and non-maintenance personnel considered human error accounts for a large proportion of maintenance error, and individual-related factors and management-related factors are the most frequent reasons for maintenance error. The outcomes also indicate that non-maintenance perspective should not be ignored because it can provide abundant information which is not included in maintenance personnel reports and helpful to reduce error. Meanwhile, the management-related factors are as crucial as individual-related factors, which should be paid more attention.

For advanced airplane, the Safety of Flight tends to be dependent on complex flight control system. The result is a greatly increased emphasis on flight control system failure effects. FAR25 airworthiness standards are based on, and incorporate, the techniques of the fail-safe design concept. Critical FAR25 airworthiness clauses and Special Conditions about flight control system failures are analyzed. Airworthiness requirements and methods of compliance are studied. Key works in flight control system development are summarized. System safety assessments and failure state verification test are conducted for showing the compliance with airworthiness requirements.

To highlight the safety-critical areas of hypersonic vehicles through data-driven analysis, this paper applies the hazardous factors of the Preliminary Hazard Analysis (PHA) method recommended in the advisory circular AC-431.35-2A to review 99 mishap flights of hypersonic vehicles. Mishaps with complex processes are modeled and analyzed using a new graphic method for aviation accident analysis named accident tree (AcciTree). Unsafe factors identified are then examined statistically to highlight the safety-critical zones and to identify possible new hazardous factors for the PHA list. The results indicate that the first-level categories of the PHA list have been defined extensive enough by the method to cover all hazardous factors examined in the 99 mishaps; and six factors are newly identified as supplements to the second-level categories to address the hypersonic features. The top six hazardous factors are system malfunction, hazardous component, protective system, system compatibility, undesired state, and human error; and the six systems with top high occurrence frequencies are propulsion, heat protection, flight control, brake, environment control, and landing gear.

Since high demand for the safety of civil aircraft, airworthiness regulations and health management play an important role. Airworthiness and Health management are described and summarized and classified about fuel system in this paper. Finally health management system for fuel system based on airworthiness is built to testifying it's ability of ensuring flight safety and increasing aircraft economy.

Passenger behaviors and psychological characteristics are vital factors that effect the emergency evacuation strongly. The emergency evacuation simulation demo tests and recall tests were carried out in this study. Combined with questionnaires survey, passenger typical behaviors and corresponding psychology are discussed. The results show that evacuation time, safety knowledge, passenger choosing rule for evacuation exit and route, passenger behaviors when facing congestion, and other typical behaviors and psychology are important factors that effect evacuation process. The results have sound perspective for improving emergency evacuation more efficient and making computer simulation on emergency evacuation process more accurately.

Atmospheric turbulence is one of the leading causes of serious personal injuries in nonfatal accidents of commercial aircraft and poses a significant hazard to aircraft in the terminal area. The pilot control behavior, workload and its difference from the normal flight situation also have essential impact on flight safety when the airplane encountered turbulence. In this paper, a unique frequency domain method, which used the cutoff frequency and the power frequency as the key metrics, was utilized to analyze the pilot control behavior in turbulence environment for a civil transport aircraft based on piloted flight simulation data. The results show that the cutoff frequency and power frequency consider both the frequency of pilot activity and the level of the activity at the same time, and could be a useful tool to analyze the pilot control behavior.

With the continued growth of aviation transportation, there has been an increase in the events of health and aviation safety related to bleed air contamination, which may degrade the cabin air quality to be threats to the heath of occupants, furthermore, affect the ability of flight crew and cabin crew to perform their duties. Such safety threats are seriously concerned by many civil aviation authorities and have been partially included in the airworthiness regulations. The frequency of such kind of events were investigated after reviewed the data from public literatures comprehensively to estimate the frequency of air supply contamination events involving engine oil or hydraulic fluid and obtained many useful findings. And then current airworthiness standards and the possible further development were summarized and analyzed, including design requirements of transport category airplane and aero-engine. Lastly an analysis model was developed to help showing the compliance of bleed air contamination, and the procedure to apply that model was brought out and demonstrated through an example. Furthermore the numerical tools to determine the retention ratio were constructed and validated partially through the experiments from public literatures. Such numerical models could provide more detailed information of the contaminate transportation process in ECS, which will be helpful for the design of the monitor and filter equipment in the bleed air system.

The risk simulation model of aero engine failure has been developed based on Monte Carlo method. The model has been established to predict and evaluate the failure risk of aero engine during operational phase to ensure the reliability and security. Risk assessment of a particular engine was conducted on the basis of the failure events hazard level and the corresponding risk guidelines. During the assessment, three reasonable corrective actions have been developed and estimated to analyze the effect of different maintenance methods and inspectional intervals on the failure risk factor.

This paper discussed the classification of aircraft zones related to fire based on the existence and characteristics of aircraft flammable fluids and ignition sources as well as fire safety provisions in order to establish the aircraft level safety requirements. Then, the aircraft fire safety airworthiness design process has been presented to allocate the aircraft level safety requirements in terms of zones. And the aircraft manufacturers can use this process as a guidance to perform their fire safety design and demonstrate the compliance of aircraft fire safety.

This paper has developed a framework for surrogate-based sensitivity analysis in SSA considering the complexity of Heavy-Fueled Engines (HFE) models. Multi-dimensional HFE whole engine models are extreme time consuming and computationally expensive and not practical for engineering applications. To reduce the computational costs, Artificial Neural Networks (ANN) is selected as surrogate model to establish high-fidelity HFE system model. Based on the developed ANN model, global sensitivity analysis is conducted to provide information on parameters importance, which are significant in complex system safety analysis. The results reveal that, by using global sensitivity analysis, the parameters could be ranked with respect to their importance, including first order indices and total sensitivity indices. For the particular study, the importance indices indicate that compression ratio and start angle of injection are more important with respect to the influence on the maximum pressure for HFE. The results also show that ANN-based surrogate model is an efficient way for sensitivity analysis in HFE safety assessment.

This paper analyzes the various factors affecting the flying safety and flight control on plateau airports, and the problems of flying at plateau airports, pointed out the necessity to modify the pilot model on plateau airport hypoxia condition, proposed the method to analyze closed-loop stability on plateau airport conditions, and finally given some suggestions for improving flight safety on plateau airports

Discussion on airworthiness management of CFM56 products in FAA and EASA is presented in this paper. The successful experience of the CFM56 series is summarized about engine model design, type certification and continuous aviation safety management, which would provide some guidance for international cooperation at engine design, manufacture and airworthiness management in civil aviation.

General aviation industry plays a decisive role in the national economy, “Gradually open up the low-altitude airspace” policy has in fact started providing space for the growth of general aviation, especially for the need of Light Sport Aircraft (LSA). This paper Summary LSA management experience of the United States, through the analysis of management situation of China, gave the LSA operation airworthiness management proposals in the situation of opening low-altitude airspace.

Based on the 250-passenger BWB configuration, the effect of the configuration of flap on BWB civil aircraft flight loading during takeoff and landing is studied by computational fluid dynamics. Flight loading varied with the flap deflection, area and the layout is discussed. It is shown the existence of flap makes the angle of attack smaller in takeoff and landing and aerodynamic forces and moment larger. In addition, it can change the loading distribution along span wise of the wing and affect the structural safety. Especially, increased pitch moment can make flight safety worse in takeoff and landing. In some cases, it is important that the function of flap is to improve the drag significantly and reduce the distance of taxiing to benefit to safety in landing. The airworthiness will have to be re-evaluated before the flaps are used in BWB on basis of the structural and flight safety considerations according to CCAR25.

On the basis of the preceding risk identification and the risk evaluation index systems, this paper applied AHP to determine the weight of risk evaluation indexes and fuzzy comprehensive evaluation to obtain the risk level under the condition of RNP technology operation into Nyingchi airport from the four aspects of human risk factor, equipment risk factor, environment risk factor and management risk factor. In order to improve the plateau flight safety, it made further efforts to put forward measures of risk control and prevention for plateau flight based on the risk evaluation results.

As to guarantee flight safety when system failures occur, modern fly-by-wire flight control systems for commercial aircraft incorporate reconfiguration control modes. While relaxed static stabilities (RSS) are utilized on most new designed fly-by-wire airliners, the flying qualities design become a major concern when reconfiguration flight control laws are developed. The aim of this paper is to analyze the reduction of flying qualities when reconfiguration laws are activated. Longitudinal and lateral-directional control laws, along with their alternative and direct modes, were developed for a commercial aircraft with relaxed longitudinal and directional static stabilities. Flying qualities assessment with reconfiguration laws were carried out based on the handling qualities rating method (HQRM), which has certification levels connected to military specifications such as MIL-STD-1797A. The analysis indicated that short period mode and Dutch roll mode are most affected in the downgrade of flight control law. It is suggested that qualities of these modes should be guaranteed as priority when reconfiguration laws are designed.

Safety cases, as a means of demonstrating system safety, have been increasingly used as the basis for system assurance, especially in safety or mission-critical systems in fields such as offshore installation, railway operations, nuclear plants, and air traffic control. Despite the increased adoption of safety cases in the aforementioned areas, the usage of safety arguments is still limited in the certification of a civil aircraft design. This paper provides 1) a brief overview of the key regulations and guidelines in support of aero-system certification especially at the development stage; 2) a review of the history, the essence, and the practice of safety cases; 3) an analysis of the role of processes and safety arguments in aircraft certification; and 4) recommendations on the future work in terms of further application of safety cases in aircraft certification.

The ergonomics design of transport category airplane cockpit is of great importance to the efficiency of flight crew operation and has a major impact on the flight safety. In this work, the ergonomics design elements in the cockpit are analyzed. The elements are collected from airworthiness regulations, industry standards, features of new generation airplane cockpit and the interaction process analysis results. Using hierarchical cluster approach, the ergonomics design elements are clustered, and the ergonomics design elements for transport category airplane cockpit are determined. The cockpit design process is presented on the basis of axiomatic design theory and a framework for ergonomics design of transport category airplane cockpit.

Safety is the most important consideration in civil aviation, and human factors directly influence the safety of an aircraft. This paper focused on implementing the human factors by using improved NASA-TLX to enhance the safety of aircraft in the design phase.

Aviation safety regulations permit the carriage of an infant passenger on the lap of an adult. This practice is known to be unsafe in emergency landing scenarios; however, no prior study has quantified the risk of injury associated with this seating configuration. Depending on the jurisdiction the flight is operating under, the infant must either be unrestrained or restrained by a supplementary loop belt. No prior study has compared the relative safety of these restraint conditions. A validated numerical model was used as an experimental platform for the prediction of occupant injury potential with a focus on head injury. Observations were used in three ways: to compare the relative safety of different configurations, to evaluate safety in terms of a published occupant protection standard and to predict the occurrence and severity of a particular injury. Analysis involving the lap-held infant demonstrated that this seating arrangement does not represent a means of protecting an infant from injury in an emergency landing scenario regardless of restraint condition. During the impact sequence an unrestrained lap-held infant is likely to be projected through the aircraft cabin, while a lap-held infant restrained by a supplementary loop belt is at risk of serious abdominal injuries.

In the circumstance of rapid progress of Chinese aviation industry and ambitious development of aeronautical manufacturing projects, the current airworthiness certification system of Civil Aviation Administration of China (CAAC), which includes the legislation frame, airworthiness regulations and organization chart, is introduced. Now the CAAC airworthiness certification system still faces the challenges of the industry progress. The vision of CAAC airworthiness certification system and the key elements of the system improvement are discussed. The main concern is how can the industry's resources be used for the airworthiness authority to fully take authority's responsibilities during certification. The traditional way to use industry's resources is implementing delegation system. With delegation system, the authority can directly use industry's resources. Considering that the delegation system depends on the individual decision-making, different behaviors of individuals as a designee and in organization are studied from the viewpoint of the organizational behavior. Requiring design organization to implement the design assurance system (DAS) is selected as another option, and the idea of organization certification is presented. After carefully comparing the advantages and disadvantages between product certification and organization certification, and also between designee system and design organization respectively, the methodology of using designee system and requiring design organization to implement the design assurance system (DAS), as the way of transferring from the solely aviation product certification to the certification of product and organization, is proposed. And the core requirements of DAS are concluded. Following the vision, key elements, and clear development methodology of CAAC airworthiness certification system, detailed actions to achieve the final goal are presented as well.

The purpose of this study is to reduce the aviation accidents and incidents induced by flight crew errors. A flight crew errors analysis and classification system is developed preliminary. In combination with aviation flight accidents exploration, and interviews with pilots, the human error modes which will occur in the flight task are identified. A quantitative method to assess flight crew errors is established on Technique For Human Error Rate Prediction (THERP). In a case study, the takeoff task is analyzed, the human error modes and consequences are identified, and the failure probability of takeoff task is calculated. Those results are useful for SSA (System Safety Assessment) to improve the aircraft safety design.

To gain access to new markets and technology resources, as well as low-cost and multi-currency-based sourcing and offset obligations, major Original Equipment Manufacturers (OEMs) are expanding their footprint in Asia. It is mandatory to have EASA/FAA approvals including Civil Aviation Airworthiness approvals by DGCA, India for organizations engaged in manufacture of an aircraft/ component/ item of equipment or part to export products for commercial aircraft applications. Reyaneh Sayafi, Florence Leblond developed a Production Organization Exposition scheme taking into account EN9100 requirements. The objective was to study requirements of AS/EN9100, EASA, FAA and DGCA (India) to harmonize and prepare a concise Production Organization Exposition (POE) that complies with all requirements. This paper includes development of Production Organization Exposition (POE) manual to incorporate requirements of Quality Management Systems- Requirements for Aviation, Space and Defense Organizations (AS/EN 9100), European Aviation Safety Agency (EASA) Part 21 G, Federal Aviation Administration (FAA) CFR 14 Part 21 G and DGCA, India Part 21 Subpart G. A detailed comparison of AS/EN 9100, EASA, FAA and DGCA (India) requirements of Production Organization Exposition (POE) is conducted. A cross reference matrix has been prepared. For each important topic, it covers regulations, similarities and differences and then a harmonization which defines a common structure of procedures of Production Organization Exposition (POE) incorporating AS/EN9100, EASA, FAA and DGCA (India) requirements. Efforts in planning stage will ensure stringent requirements are deployed and enable minimum preparation time required to take up approvals from Civil Aviation Authorities.