Safety Of Civil Aircraft Research Articles

The angle of attack and side-slip angle estimation for civil aircraft

The angle of attack and side-slip angle are two important flight parameters that directly affect the flight safety of civil aircraft. This paper studies the estimation method for the angle of attack and side-slip angle according to air-data system, inertial navigation system, and aircraft aerodynamic data to improve flight safety under the condition of icing, failures, and improper maintenance. Flight tests show that the proposed estimation method is feasible, reliable, and has better accuracy. Furthermore, flight test data analysis shows that the angle of attack estimation error is within 1 degree, and the side-slip angle estimation error is within 1.5 degrees which can meet the requirements of engineering application.

Research on Monte Carlo simulation of CAT III auto-landing system

Approach/Landing is the phase of most accidents occur to endanger civil aircraft safety. CAT III autoland operation can improve the safety and reliability of aircraft when approach and landing in bad weather conditions, and reduce pilot’s working loads, so CAT III autoland control law design is an important task in advanced flight control system research. However, the most of the related researches are requirement based rather and scenario based. Firstly, the article analyzes the Monte Carlo simulation requirements based on airworthiness requirements of auto-landing system and proposes a Monte Carlo simulation model scheme considering the uncertainty of aircraft dynamic model and the actuator model, the error of sensors and the disturbance of wind, then implements the simulation based on a desktop simulation platform. The simulation result shows that the designed auto-landing system can assure the safe and stable landing of the aircraft on the condition of all kinds of uncertainty, the touchdown point, the vertical landing speed and the attitude are all compliance with the expectation criteria, satisfying the requirement of airworthiness items.

Generation of Guidance Commands for Civil Aircraft to Execute RNP AR Approach Procedure at High Plateau

RNP AR is an operational procedure that uses the aircraft’s airborne navigation equipment and global positioning system to guide the aircraft to take off and land, and it is an effective means to ensure the flight safety of civil aircraft at high-plateau environments. In this paper, a three-dimensional, precise guidance command generation method for performing an RNP AR approach procedure is proposed. The lateral navigation transition paths between different segments are constructed, and a lateral segment switching strategy based on the angular bisector is introduced. To illustrate the availability of the proposed algorithm, a simulation based on the RNP AR approach procedure of Jiuzhai Huanglong Airport is operated, and it can be drawn from the results that the proposed algorithms can provide lateral and vertical guidance capabilities that meet the requirements of RNP AR approach.

Research on Intrinsic and Environmental Conditions Hazard Analysis Methods for Civil Aircraft

SAE ARP 4761 stipulates that an area safety analysis must be performed in every area of the aircraft to ensure the safety requirements of the equipment. The study proposes the Intrinsic Hazard Analysis and environmental conditions hazard analysis methods to identify potential neighboring hazard sources, assess the weakness of the area, and solve the problem of incomplete input of area safety analysis. The IEHA analysis method has been verified and applied in the actual type of work, which plays the role of systematic and comprehensive identification of hazard sources and discovery of potential risks, and has practical engineering application for the development of domestic large aircraft. It provides a good theoretical basis and technical reserve for establishing the method and process of civil aircraft safety design verification.

Deep-Learning-Based Model for Accident-Type Prediction During Approach and Landing

Modern civil aircraft is designed for a greater workload. While the volume of air traffic has grown exponentially over the past two decades, the total number of accidents has been flat or slightly higher than past averages. However, the fatality and property losses caused by aviation accidents are unbearable even if they happen only once. As reported by a Statistical summary from Boeing in 2019, nearly 40% of the deaths occurred during the final approach and landing. A deep-learning-based model for accident-type prediction during approach and landing was established, which explores the implied association between accident types and accident factors from the risk factors affecting the occurrence of unsafe events. First, based on the investigation reports of civil aircraft fatal accidents in the recent 43 years, 20 common accident risk factors were extracted by the human factors analysis and classification system method. Implicit association of accident factors was excavated by association rules and 6 key factors were extracted from 20 factors. Back propagation neural network, Radial basis function neural network, and Elman neural network applicable to the classification were selected for multiple learning and training. The classification results showed that the comprehensive prediction accuracy of accident types reaches 86.7%, which can effectively determine the types of accidents that may occur during the approach and landing phases of civil aircraft, make emergency measures in advance, and incorporate key accident factors into the assessment scope of civil aircraft safety management system to ensure the aviation operation safety.

Three-Dimensional ANP Evaluation Method Based on Spatial Position Uncertainty under RNP Operation

Performance-based navigation (PBN) operations based on the required navigation performance (RNP) operations are the trend for civil aviation in the future. In order to further ensure the safety and efficiency of civil aviation operation, RNP will transition from 2D to 3D/4D. Accurately evaluating the actual navigation performance in three-dimensional directions (3D ANP) under civil aircraft RNP operation is important to guarantee the safe flight of civil aircraft. However, the traditional two-dimensional ANP evaluation method mainly focuses on plane navigation performance along the track, lacks the evaluation of the vertical direction. Moreover, the traditional three-dimensional accuracy evaluation method is based on the assumption of three-dimensional independence and uniformity, which can only carry out approximate calculation, and the evaluation result is inaccurate. Therefore, this paper constructs a three-dimensional ellipsoid error probability (EEP) evaluation model for the spatial position uncertainty of the navigation output of the flight management system in three-dimensional directions, and gives the three-dimensional accurate ANP calculation results through iterative numerical integration. The simulation results show that the evaluation method proposed in this paper can accurately evaluate the actual navigation performance of the airborne navigation system in all directions of 3D space, and has higher evaluation accuracy and precision than the traditional ANP evaluation method, which is of great significance to ensure the flight safety of civil aircraft under 3D/4D RNP operation in the future.

State flight safety of civil aircraft

The article is devoted to the study of the system of state regulation and management of flight safety, the definition of the subjects of such activities. The research methodology is based on the methods of documentary analysis and synthesis, comparative analysis, objective truth, which allows to systematically trace the impact of legal regulation in the field of air transport. As a result, it was stated that state regulation is an important component in ensuring the safety of flights of civil aircraft. With proper legal regulation, a high level of aircraft safety will be ensured. The state policy of ensuring the safety of aircraft in civil aviation is a set of goals, objectives, priorities, principles, strategic programs and planned measures developed and implemented by public authorities, which allows the state to achieve its goals in the aviation industry, using legal, economic, administrative and other methods and means of influence, based on available resources. The peculiarity of this public policy is that, first, it is closely linked to both foreign and domestic processes in the country; secondly, has a great influence on the development of all socio-economic
 relations; thirdly, it is provided by a system of public administration bodies headed by the head of state; fourth, it is quite dynamic and costly; fifth, it needs constant control and adjustment by the state. State regulation of flight safety of civil aircraft consists in the formation of state policy and development strategy, defining tasks, functions, conditions of state bodies and use of Ukrainian airspace, application of aviation security measures, adoption of mandatory aviation rules of Ukraine, state control over their implementation and establishing responsibility for their violation. Analysis of flight safety and aviation statistics in recent publications and studies.
 The results of the analysis of statistical data on aviation events that have occurred over the past six years indicate a significant deterioration in flight safety during aviation operations, both in absolute and relative accident rates.
 To increase the level of flight safety, public authorities and aviation entities should take effective measures to implement a safety management system in accordance with the requirements of ICAO, the European Aviation Safety Agency and the European Organization for the Safety of Air Navigation (Eurocontrol) [4, с. 117].

Research on the Particular Risk Analysis Model of Sustained Engine Imbalance on Civil Aircraft

In order to demonstrate the aircraft continued safe flight and landing after fan blade out (FBO), Sustained Engine Imbalance Particular Risk Analysis, as part of the civil aircraft safety assessment, is seriously required to implement. Under the guidance of AC25-24 “Sustained Engine Imbalance”, the specific analysis model are given, combined with engineering application experience on civil aircraft development and certification. The model and methods presented herein provide a valid approach and guidance for safety design requirements capturing in aircraft design and certification demonstration regarding Sustained Engine Imbalance.

Legal consequences for the state arising from the use of weapons against civil aircraft: review and legal framework development

The authors elaborate on one of the controversial issues of international air law - safety of civil aircraft in flight in respect of the use of weapons against it. The first part of the present article considers major aerial accidents arising from shooting down the civil aircraft for the last 70 years as a factual basis for further legal analysis. In the second part, the authors back up customary prohibition of the use of weapons against civil aircraft in flight and legal consequences for states for violating the mentioned principle. The authors investigate the grounds for the security exception and conclude that the only grounds for derogation from the principle of non-use of weapons against civil aircraft is Article 51 of the UN Charter proclaiming the inherent right of the state to self-defence. Even in this case, the application of the security exception by the state is tolerated by using a set of precautions before employment of weapons. Finally, authors conclude that compensation for victims reflects the inevitable monetisation of human lives. Moreover, states negotiations reveal the controversial reality of trade-offs between them, where compensation amounts are occasionally affected by external political factors and current position of a particular state in the international community.

The Interception of Civil Aircraft

This article investigates the regulatory framework that governs the interception of civil aircraft. It analyses the various circumstances that may justify such interventions as well as the main legal principles that apply to their conduct. Particular attention is given to the States’ obligations under the Chicago Convention, and more specifically the obligation of due regard for the safety of civil aircraft that applies to the adoption by States of regulations for their State aircraft. The research investigates the civil-military cooperation framework and the procedures that must be followed by the various civil and military stakeholders involved with a view to reducing the need for interceptions and to ensure that those that ultimately need to be undertaken can be executed without endangering the safety of civil aircraft. Interception; Due regard; Civil military cooperation; Article 3bis; Unidentified and strayed aircraft

Research review on design method of ice protection system for civil aircraft based on ice-tolerant concept

Icing is an important disaster-causing factor which threatens the flight safety of civil aircraft and a major safety issue of concern for the airworthiness. The design of icing protection system based on ice-tolerant concept can minimize the impact of icing on aerodynamic characteristics and fully utilize the potential of flight performance, which is the frontier direction of current icing protection research for civil aircraft. This paper aims at the requirements of civil aircraft flight safety design and airworthiness certification. The design method of civil aircraft icing protection system based on the concept of ice-tolerant capacity is analyzed from two aspects. One is the capacity of ice-tolerant for aircraft frame, the other one is the design of ice-tolerant with active control. The optimum design strategy of wing in aerodynamic performance considering icing loss is refined and the design idea of ice-tolerant protection control system based on flight control law reconstruction is formed. The change from passive flight safety of icing to active safety design of icing can effectively improve the survivability and safety of civil aircraft under icing weather conditions.

Assessing the risk of windshear occurrence at HKIA using rare‐event logistic regression

AbstractLow‐level windshear poses serious hazards to the flight safety of civil aircraft. The objective of the study was to assess the risk of windshear occurrence within 1 hr at runway corridors at Hong Kong International Airport (HKIA). Windshear report records from HKIA and weather data around HKIA were obtained from Hong Kong Observatory (HKO) between January 2016 and December 2018. The rare‐event logistic regression was employed to evaluate windshear risk considering the imbalanced nature of the data. Several explanatory variables were found to be significantly correlated with the risk of the hourly occurrence of the windshear. Results indicated that at HKIA, March, April, July and August are associated with a higher likelihood of windshear events, while November suffered a significantly lower windshear risk. Besides, winds from the east, southeast, south and southwest are more likely to cause windshear events at HKIA. However, the study found that it was hard to predict windshear occurrence precisely only with the hourly weather variables due to the transient and sporadic nature of windshear. Therefore, more refined data are needed to improve the prediction performance of regression models for windshear occurrence. The present study is the first to analyse the windshear occurrence at airports using the rare‐event logistic regression method. Findings from the study can provide some references and valuable information for related researchers to understand low‐level windshear.

Multi-objective optimization of a new special-shaped tube for heating deicing fluid

The ground deicing heating system is an important equipment to ensure flight safety of civil aircraft in winter. As the main element, the heating tube directly affects the working efficiency of the system. The deicing fluid is high viscosity mixture. To improve heating efficiency of deicing fluid, a new special-shaped tube is proposed, which is named double-spiral trapezoidal grooved tube. The upper base width (m), groove depth (h) and base angle (θ) are the important structural parameters of the new tube. The optimal Latin hypercube design is applied to carry out the experiment design of m, h and θ. Nusselt number (Nu), flow resistance coefficient (f) and performance evaluation criteria (PEC) are selected as the optimization objectives. Then, the response surface approximation model is established to conduct sensitivity analysis. Based on the model, NCGA and NSGA-II algorithms are, respectively, introduced to perform the multi-objective optimization. The results show that NSGA-II is better than NCGA. When \(m \in \left[ {0.17, \, 0.33} \right]\), \(h \in [1.06, \, 1.08]\) and \(\theta \in \left[ {84.06, \, 84.75} \right]\), the best range of optimization objectives is \(Nu \in \left[ {86.04, \, 87.81} \right]\), \(f \in \left[ {0.70, \, 0.73} \right]\) and \({\text{PEC}} \in \left[ {1.60, \, 1.62} \right]\). With the growth of turbulence intensity, PEC > 1, and Nu increases by 4–27%. As a result, the heating efficiency of the new tube is superior to the original tube.

A zonal safety analysis methodology for preliminary aircraft systems and structural design

ABSTRACTZonal Safety Analysis (ZSA) is a major part of the civil aircraft safety assessment process described in Aerospace Recommended Practice 4761 (ARP4761). It considers safety effects that systems/items installed in the same zone (i.e. a defined area within the aircraft body) may have on each other. Although the ZSA may be conducted at any design stage, it would be most cost-effective to do it during preliminary design, due to the greater opportunity for influence on system and structural designs and architecture. The existing ZSA methodology of ARP4761 was analysed, but it was found to be more suitable for detail design rather than preliminary design. The authors therefore developed a methodology that would be more suitable for preliminary design and named it the Preliminary Zonal Safety Analysis (PZSA). This new methodology was verified by means of the use of a case study, based on the NASA N3-X project. Several lessons were learnt from the case study, leading to refinement of the proposed method. These lessons included focusing on the positional layout of major components for the zonal safety inspection, and using the Functional Hazard Analysis (FHA)/Fault Tree Analysis (FTA) to identify system external failure modes. The resulting PZSA needs further refinement, but should prove to be a useful design tool for the preliminary design process.

Safety critical systems design for civil aircrafts by model based systems engineering

A civil aircraft safety critical system design scheme using model based systems engineering (MBSE) is proposed in this paper, with considering the civil aircraft/systems design standard and thchnology frontier fields. Considering the availability and integrity of the system functions, civil aircrafts/systems design and safety assessment process are esteblished by using MBSE. Civil aircraft brake system development and assessment scheme are proposed by MBSE tools IBM DOORS and Rational Rhapsody. Use cases, functions flow, and state-machines of the system are set up by corresponding models in requirement analysis, function analysis and design synthesis phases. The system architecture which can guarantee the function availability and safety is designed by fault tree analysis. System models are verified by SysML and Simulink collaborative simulation, and Panel diagram interactive interface.

Международно-правовые аспекты обеспечения безопасности полетов гражданских воздушных судов в районах боевых действий и военных учений

Introduction. Despite the international aviation community’s attempts aimed at improvement of safety of air transport and reduction of the number of air accidents, unfortunately, many threats to safety of civil aircraft still exist to date, including armed conflicts and other military activities taking place in different parts of our planet. Malaysian Boeing 777-200 crash of 17 July 2014 in the eastern Ukraine killing 283 passengers and 15 crew members has become the tragedy clearly showing the risks, to which the civil aircraft and passengers on board flying in the airspace over the areas of armed conflicts, are exposed. In light of this accident, the author examines the present international legal regime of safety of civil aircraft flying over the areas of armed conflicts and military exercises, identifies the problems of this regime and proposes the ways of its improvement. Materials and methods . The present research has been conducted on the basis of international air law treaties, the documents of International Civil Aviation Organization (ICAO), as well as the works of Russian and foreign international law experts. The methodology of the research is based upon general scientific and special methods, including dialectical method, methods of analysis and synthesis, deduction and induction, comparative legal method. Research results . On the basis of his research the author concludes that neither the present-day international legal regime of safety of civil aircraft flying over the areas of armed conflicts and military exercises, nor existing rules of international air law prohibiting use of weapons against civil aircraft can prevent accidents similar to Malaysian airplane crash of 17 July 2014. In view of this conclusion, the author proposes improvement of international legal regime of safety of civil aviation, and in particular, amendment of the Convention on International Civil Aviation of 1944 (“Chicago Convention of 1944”) aimed at enhancement of States’ obligations relating to restriction of flights of civil aircraft within their sovereign airspace during armed conflicts or other military activities. Discussion and conclusions . The author examines treaty and customary rules of international law governing the issues of safety of civil aircraft flying over the areas of armed conflicts and military exercises as well as ICAO standards and other acts (documents) and concludes that they do not precisely oblige the States to restrict or prohibit flights of civil aircraft in their sovereign airspace during armed conflicts, military exercises or other hazardous military activities. Moreover, the provisions of the Chicago Convention of 1944 and other international treaties prohibiting the use of weapons against civil aircraft are imperfect and do not fully protect civil aviation from different types of weapons. Therefore, the ICAO’s work following Malaysian airplane crash of 17 July 2014 for the purpose of enhancement of protection of civil aviation from the threats arising from armed conflicts and other hazardous military activities appears insufficient and must include more efficient measures, such as adoption of new international treaty rules containing precise States’ obligations.

Research on safety evaluation of civil aircraft based on the grey clustering model

PurposeThe purpose of this paper is to construct a grey clustering model based on the nonlinear whitenization weight function and to assess the safety of civil aircraft by using a quantitative method.Design/methodology/approachAccording to the running stage of civil aircraft safety assessment issues, first the civil aircraft safety evaluation index system is constructed by using a qualitative method. Taking the information duplication between indicators, the grey relational analysis method is used to filter the key indicators, then the grey clustering evaluation model of nonlinear whitening right function is built to evaluate the safety of civil aircraft and the algorithm steps of the evaluation model are given. Finally, the model is validated by collecting the parameters of nine different civil aircrafts at home and abroad.FindingsThe results show that the safety level of different types of aircraft is different due to the different index parameters, and to some extent, explain the rationality and scientificity of the method proposed in this paper to solve the problem.Practical implicationsThis paper gives a complete set of security assessment methods, which can be used to evaluate the security of civil aircraft in the operational phase quantitatively, scientifically and reasonably. Furthermore, it can be extended to other complex system security or stability assessment issues.Originality/valueIt not only provides the supplement and perfection of the safety assessment method in the theoretical system to a certain extent, but also provides a theoretical guidance to solve the problem of civil aircraft system safety assessment of civil aircraft manufacturing enterprise all over the world. At the same time, the nonlinear grey clustering evaluation model constructed in this paper is an improvement of the traditional model, which is, to some extent, the improvement of the grey clustering evaluation theory.

Bat collisions with civil aircraft in the Republic of Ireland over a decade suggest negligible impact on aviation safety

Globally, collisions between wildlife and aircraft are a serious threat to aviation safety. While reported collisions have increased in recent years, the impact of these collisions on air safety is rarely quantified. Here, we report all bat collisions (bat strikes) with civil aircraft known to have occurred in the Republic of Ireland over the 10-year interval, 2006–2015. Morphological and/or DNA identification techniques were used to identify chiropteran specimens to species level. In total, carcasses or remains from five bat strikes—three Leisler’s Nyctalus leisleri, one Soprano Pipistrelle Pipistrellus pygmaeus, and one Natterer’s Myotis nattereri—were recovered. The collisions are discussed in the context of (a) the rate of chiropteran strikes in relation to the number of civil aircraft movements and (b) possible damage caused to aircraft. Overall, however, bat strikes with aircraft appear to have a negligible effect on civil aircraft safety.

AUTOMATION, REMOTE CONTROL AND RELIABILITY OF THE LIGHTING SYSTEM OF MODERN CIVIL AVIATION AIRPORT

One way to improve the safety of civil aircraft - it Automation categorized by the International Classification of aerodrome lighting systems. Automation is provided by the remote control of lighting to give the necessary signal to the system and its individual elements, in accordance with international regulatory and technical documentation for the equipment type. The level of reliability of the equipment, which is part of the automated control systems of the aerodrome lighting system, implemented at the level of design and production of the main manufacturers of the equipment and compliance with ICAO specifications and technical documentation. The analysis of modern automated lighting systems airfields with the help of programmable logic controllers and control using radio resources allowed us to determine the main directions of operation of the aerodrome lighting systems and ensure the safety of civil aviation on the ground

Model–Based Techniques for Virtual Sensing of Longitudinal Flight Parameters

Abstract Introduction of fly-by-wire and increasing levels of automation significantly improve the safety of civil aircraft, and result in advanced capabilities for detecting, protecting and optimizing A/C guidance and control. However, this higher complexity requires the availability of some key flight parameters to be extended. Hence, the monitoring and consolidation of those signals is a significant issue, usually achieved via many functionally redundant sensors to extend the way those parameters are measured. This solution penalizes the overall system performance in terms of weight, maintenance, and so on. Other alternatives rely on signal processing or model-based techniques that make a global use of all or part of the sensor data available, supplemented by a model-based simulation of the flight mechanics. That processing achieves real-time estimates of the critical parameters and yields dissimilar signals. Filtered and consolidated information is delivered in unfaulty conditions by estimating an extended state vector, including wind components, and can replace failed signals in degraded conditions. Accordingly, this paper describes two model-based approaches allowing the longitudinal flight parameters of a civil A/C to be estimated on-line. Results are displayed to evaluate the performances in different simulated and real flight conditions, including realistic external disturbances and modeling errors.