Journal of Civil Aviation University of China

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Sensitivity analysis of engine safety affecting factors based on the turbocharging

system model

LI Guoa, , WANG Zilub , TENG Yidab , XU Tonggeb

Journal of Civil Aviation University of China 2025, 43 (1): 1-10.

Abstract （2290）

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Adopting turbocharging system can effectively restore the high-altitude power performance of the engine and improve the working ceiling of general aircraft. However, while improving the engine performance, its safety should

also be given sufficient attention. In order to improve the safety of the turbocharging system of aviation reciprocating engine and provide suggestions for actual operation, this paper combines model-based system safety analysis,

"V" shaped safety analysis, response surface methodology (RSM), and Sobol factor sensitivity analysis method, and

taking Rotax914 as prototype, a quasi dimensional model for the entire engine and fitting equation are constructed

for global sensitivity analysis. The sensitivity of the turbocharging system performance of aviation reciprocating engine to different safety affecting factors are analyzed and compared. The results indicate that the sensitivity index of

altitude is much higher than other factors, and the sensitivity index of intake valve diameter is higher than that of

exhaust valve diameter but they are similar in magnitude. The effective length of air filter has almost no effect on the

engine turbocharging system under normal operating condition. Therefore, during the actual operation, the change

range of safety affecting factors can be adjusted according to the analysis results, in order to reducing the uncertainty of key factors and conducting efficient and intuitive safety analysis.

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Determination and verification of severe anti-icing working conditions

during the entire flight phase

HU Xuelan, WANG Yidan, NIU Yifan, YAO Jiawei

Journal of Civil Aviation University of China 2025, 43 (1): 11-19.

Abstract （1748）

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Determining the severe working conditions that meet the airworthiness requirements is a necessary step in the airworthiness certification process of wing icing, and traditional calculation methods of severe anti-icing working

conditions require a large amount of repetitive calculations, therefore, this article proposes a simplified method for

determining severe working conditions based on Appendix C of CCAR-25 (Appendix C) by combining Latin hypercube sampling and severity assessment index, considering the entire flight phase and full ice accumulation

conditions, and its feasibility is verified by computational fluid dynamics model. Firstly, based on Appendix C, the

parameter intervals for icing working conditions were clarified, and Latin hypercube sampling was used to discrete

the continuous parameter intervals and obtain the combined working conditions. Secondly, the severity assessment

index is introduced to rank the icing working conditions, and the computational fluid dynamics simulation calculation of wing icing under univariate icing working conditions and continuous maximum icing working conditions is

used to verify that the severity assessment index can be used as an evaluation index for severity assessment under

the same ice type, with the amount of icing (including the total mass of icing and the maximum icing thickness). It is

proved that the larger the absolute value, the more severe the working working conditions. Due to the significantly

longer flight time compared to other flight phases, the waiting phase has the highest degree of icing severity, and all

severe working conditions are in the waiting phase. Finally, the severe condition based on Appendix C are given by

the severe condition determination method proposed in this paper.

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Study on the influence of different loading conditions on lumbar response index

RUI Xiangqian , CUI Shurui a , SHI Xiaopengb

Journal of Civil Aviation University of China 2025, 43 (1): 20-26.

Abstract （1970）

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Lumbar load and dynamic response index (DRI) are two common lumbar response index used to assess passenger

lumbar injuries during emergency landing of aircraft. To elucidate the differences between these two metrics, firstly,

the seat-occupant finite element model and the occupant upper limb lumped parameter model were established in

this paper. Secondly, a comparative verification is conducted between the seat-occupant finite element model and

the occupant upper limb lumped parameter model. Finally, a parametric analysis was conducted on these two lumbar response index by changing the loading time and loading peak value. The results show that the DRI value calculated by floor acceleration is lower than that calculated by pelvic acceleration, and when the loading time is constant, the DRI value shows an increasing trend with the increase of loading peak value. When the loading peak value is constant, the DRI value shows the trend of increasing first and then decreasing with the increase of loading

time. When the speed change is constant, the DRI value shows an increasing trend with the increase of the loading

peak value. In summary, by sorting out and analyzing the principle of DRI, it is helpful to promote the continuous

improvement of the criteria for determining occupant lumbar injuries.

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Study on degradation and thermal runaway characteristics of commercial

lithium-ion battery fast-charging

ZHOU Xiaomeng a, b , CAI Jinlea, b , GUO Yiboa , LIAO Yunlong b

Journal of Civil Aviation University of China 2025, 43 (1): 27-32.

Abstract （1975）

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To identify the impact of fast-charging aging factors on the operation and thermal safety performance of lithium-ion

batteries, this study first conducts cyclic aging tests on commercial 18650 lithium-ion batteries using 1C/2C charging rate to characterize capacity decay, electrochemical impedance, operating temperature rise, and other characteristics of the battery. Secondly, on the self built thermal runaway platform, compare the differences in thermal runaway behavior and temperature characteristics between fresh and fast-charging aged lithium-ion batteries are compared. The results show that the aging process of lithium-ion battery is nonlinear, and presents three stages corresponding to different aging mechanisms. Increasing the fast-charging rate leads to a significant magnify in charge

transfer impedance and ohmic impedance. The cycle life of lithium-ion batteries with 2C charging rate aging shortens rapidly, and abnormal heat release behavior occurs during the cycle, and the maximum surface temperature reaches 75 ℃ during the charging phase, which not only accelerates the capacity decay of the battery, but also increases the risk of thermal runaway. The results of the thermal runaway test show that the thermal runaway of aged

lithium-ion batteries is delayed and the temperature of thermal runaway is higher. Lithium-ion batteries affected

by fast-charging aging factors have better thermal stability, but the process of thermal runaway is more dangerous.

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Numerical study of the effect of boundary layer ingestion on the flow field

distortion of S-shaped intake

FU Wenguang, XIAO Lei, SUN Peng

Journal of Civil Aviation University of China 2025, 43 (1): 33-40.

Abstract （1473）

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: In order to study the effect of boundary layer ingestion (BLI) on the flow field distortion of the S-Shaped intake, a

short spread pressure and small offset S-shaped intake is designed in this paper, the effect of BLI on the flow field

characteristic of S-shaped intake is analyzed, and the effect of inhaling boundary layers of different thicknesses on

the outlet flow field is further researched. The results show that when the boundary layer is inhaling, the three-dimensional separation flow of the fluid inside the inlet forms a twin swirl distortion zone, low-energy fluid accumulated at the bottom of the intake tract, and forms a unique concave shape total pressure distortion zone at the exit

position. With the increase of the thickness of the suction boundary layer, the flow capacity of the inlet tract decreases, and the total pressure distortion intensity and range at the outlet section increase. However, the range of

swirl distortion slightly increases, and there is no significant change in swirl intensity.

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Research on influence of geometric parameters of airfoil on aerodynamic

characteristics of ducted coaxial double rotors

YANG Yonggang a , ZHENG Wei b

Journal of Civil Aviation University of China 2025, 43 (1): 41-46.

Abstract （1814）

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The geometric parameters of the airfoil have a great influence on the aerodynamic characteristics of the rotor. This

article focuses on numerical simulation calculations of the ducted coaxial double rotors model, studying the influence of different geometric parameters on the aerodynamic characteristics of the rotor, in order to improve the aerodynamic efficiency of the ducted coaxial double rotors. The results indicate that increasing the airfoil camber and

the installation angle of the blade root can significantly improve the total thrust of the ducted coaxial double rotors.

When the thrust coefficient is less than 0.04, the aerodynamic performance parameters of the small camber airfoil

were higher than those of the large camber airfoil. As the thrust coefficient continues to increase, aerodynamic interference and vortex trajectory disorder occurred between the lip airflow of the duct and the tip vortex of the upper

rotor, as well as between the wakes of the double rotors. Local flow separation occurred on the inner wall surface of

the duct outlet. These are the main reasons for the rapid decline of aerodynamic performance parameters of small

camber airfoil. The aerodynamic performance parameters of the large camber airfoil change smoothly, and the aerodynamic efficiency is better than that of the small camber airfoil when the thrust coefficient is large. It is a better

choice to design the rotor with a blade root installation angle for NACA6412 between 20° to 40°.

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ADS-B signals separation algorithm based on cluster weighted covariance matrix

WANG Wenyi , ZHANG Hanshuo

Journal of Civil Aviation University of China 2025, 43 (1): 47-52.

Abstract （1821）

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The automatic dependent surveillance - broadcast (ADS-B) systems transmit ADS-B signals by randomly broadcasting in the same frequency band, which will lead to the overlapping of ADS-B signals and threaten aviation safety. At present, when Capon algorithm is used to separate ADS-B signal, the pulse characteristics of ADS-B signals are not taken into account, which will greatly degrade the performance of Capon algorithm. Therefore, this paper designs a signal separation algorithm based on cluster weighted covariance matrix for ADS-B overlapping signals. Firstly, the characteristics of the array response of ADS-B signal are analyzed according to its pulse characteristics. Then, three types of snapshots with only noise, only the first signal and only the second signal are screened

out by K-means clustering method. The covariance matrix of these three types is calculated respectively. Secondly,

the covariance matrix of noise snapshots and the covariance matrix of the signal to be suppressed are selected and

the sum of them is calculated to replace the covariance matrix estimated by all snapshots in the objective function of

Capon algorithm. Finally, combined with the Capon algorithm, overlapping ADS-B signals can be separated. The

results show that this algorithm can significantly improve the performance of ADS-B overlapping signals separation.

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Integrity evaluation based on intelligent estimation of ionospheric delay

LU Dan, ZHANG Hongjian, ZHONG Lunlong, HU Tieqiao

Journal of Civil Aviation University of China 2025, 43 (1): 53-59.

Abstract （1548）

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Integrity is one of the performance requirements of civil aviation navigation systems, and ionospheric delay is an

important error source for integrity evaluation. For the single-frequency system, Klobuchar model is usually used

to correct the single-frequency signal, but the correction rate is only about 60%, and the accuracy is limited. This

paper proposes a method for estimating ionospheric delay and using it for integrity evaluation. Firstly, the ionospheric delay of observation station is trained by back propagation (BP) neural network, and the ionospheric delay

is calculated by BP neural network model of the observation station, which improves the ionospheric delay correction rate of the observation station. Secondly, the ionospheric delay of the aircraft equipped with single-frequency

receiver at its flight position is calculated by using the trained observation station BP neural network model and the

three-point interpolation method, and the integrity evaluation is carried out. Evaluation based on the data from

February to March 2015 shows that, when calculating the ionospheric delay, the BP neural network model and the

three-point interpolation method perform better than the Klobuchar model in some areas. They improve the correction rates of ionospheric delay during both daytime and nighttime, thus enhancing the accuracy of the protection level.

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MSCNN-LSTM method for monitoring the state of horizontal stabilizer system

based on flight data

ZHANG Penga , HU Fangyub , DUAN Zhaobina , LIU Jingjingb

Journal of Civil Aviation University of China 2025, 43 (1): 60-66.

Abstract （1759）

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To address the problems of insufficient fault samples, imbalanced data classes and lack of labeling in real flight data, a state monitoring method for a horizontal stabilizer system based on multi-scale convolutional neural network

(MSCNN) and long short-term memory (LSTM) network is proposed in this paper. This method does not rely on labeled data and uses unsupervised learning to monitor the state of the horizontal stabilizer system. Firstly, the quick

access recorder (QAR) data of the system in normal operation are extracted in both spatial and temporal dimensions

using MSCNN-LSTM to achieve rudder position prediction. Secondly, the residuals between the predicted and actual values of the rudder position are calculated and the distribution of the residuals is analyzed to determine the

threshold for the health state of the system. Finally, the QAR data of an aircraft is used for verification, and the experimental results show that the proposed method in this paper can accurately achieve the abnormal state identification of the horizontal stabilizer system at the flight level and can provide an abnormal alarm one flight cycle in

advance when system failure occurring.

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Research on the performance monitoring and replacement standard for damaged

hydraulic hose of civil aircraft

JIA Baohui a , MA Yuwei b , WANG Yuxina , YAO Fei b , XIAO Haijianc

Journal of Civil Aviation University of China 2025, 43 (1): 67-74.

Abstract （1898）

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Using the approach of theoretical model establishment, experimental verification and simulation analysis, the mechanical performance change rule and failure situation of the hydraulic hose of civil aircraft when containing wear

defects are analyzed in this paper. The damage status of the hose that needs to be key monitored and the wear defect

depth recommend for replacement are obtained. Based on the flow-solid coupling method, a finite element simulation analysis of composite pipeline was conducted in ANSYS WORKBENCH to explore the influence of wear defect

depth and axial length on mechanical performance under different fluid pressures, the prediction function relationship of the maximum total deformation and maximum equivalent strain of pipelines under different pressures are

given, and a composite strength model of damaged pipelines is established. According to the established model, the

pipeline does not fail before the inner wall is completely damaged, and when the wear depth and wall thickness ratio is 0.4, its mechanical performance decrease significantly, when it needs to be key monitored or replaced.

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Study and prediction of the effect of aviation grounded faults arc damage

ZHANG Tiechun , LIAO Maoqiao , ZHANG Bo , TIAN Leilei , SI Xiaoliang

Journal of Civil Aviation University of China 2025, 43 (1): 75-82.

Abstract （1286）

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Arc fault is one of the most common failure modes in aircraft electrical wire interconnect systems (EWIS). In order to

study the impact of different condition parameters on the arc damage, this paper simulated the grounded fault arc of

wire harness and fuel pipeline caused by aircraft vibration according to the vibration experimental method in SAE

AS5692 standard. The experimental research on grounded fault arc damage was carried out under the conditions of

airborne 28 V direct current (DC) power supply and 400 Hz/115 V alternating current (AC) power supply. And based

on the numerical computation method of fluid-solid thermal coupling, an arc damage prediction model was established. The results show that the arc under AC power conditions has a shorter wire harness melting time due to

higher instantaneous power compared to DC power conditions, and its arc damage is significantly smaller than that

under DC power conditions. As the vibration frequency increases, the contact time between the wire harness and

the pipeline is prolonged, and the arc damage is positively correlated with the vibration frequency. Comparing the

experimental and simulation results, the error between the two is relatively small, which effectively verifies the applicability of the arc damage prediction model and provides a certain reference for the safety assessment of the aircraft EWIS wire harness.

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Safety assessment and decision analysis of UAV considering uncertainty

TIAN Yi, RAO Haochang, XIAO Nyu′e

Journal of Civil Aviation University of China 2025, 43 (1): 83-88.

Abstract （2090）

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Quantitative safety assessment is an important means to verify whether unmanned aerial vehicle(UAV) meets the

safety requirements. Aiming at the parameter uncertainty of UAV component failure distribution, firstly, the failure

distribution parameters of basic events are modified by Bayesian theory to obtain the failure probability of top

events. Then, the safety decision analysis of top events is completed with the help of Bayesian decision theory. Finally, the safety evaluation of UAV is improved into a complete assessment and decision analysis process. The research shows that the calculation process of top event failure probability and Bayesian decision can be realized by

taking the error information generated by data link communication during the operation of a UAV as an example.

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Route planning of urban logistics UAV based on improved artificial fish

swarm algorithm

YUE Rentian , HOU Bowen

Journal of Civil Aviation University of China 2025, 43 (1): 89-96.

Abstract （1446）

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In order to safely and efficiently solve the problem of three-dimensional spatial route planning for logistics unmanned aerial vehicles (UAV), this paper first models the planning environment by improving the grid method

based on spatial obstacle avoidance and ground population density. The route planning model for logistics UAV is

established with the objective function of minimizing the sum of distance cost, grid risk value cost and height adjustment cost, and constraints are set according to UAV performance. Secondly, the standard artificial fish swarm

algorithm (AFSA) is improve by adding fish swarm jumping behavior and grid taboo table, and the improved AFSA

is employed to solve the model. Finally, the improved AFSA was compared with three other algorithms through

simulation examples and parameter sensitivity analysis was conducted on the improved AFSA. The results show

that the improved AFSA had better convergence speed than the other three algorithms, with a 9.9% reduction in

convergence time compared to the standard AFSA. Setting larger perception range parameter values resulted in

higher efficiency in route planning, while the step size parameter need to be adjusted according to the planning environment. The improved AFSA can provide reference for improving the efficiency of logistics UAV three-dimensional spatial route planning.

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Progress on civil aircraft vibration comfort design

SHU Juncheng, , HE Erming, , YIN Menghan, , ZHAO Guanchen,

Journal of Civil Aviation University of China 2025, 43 (2): 1-7.

Abstract （2344）

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In the competition of the civil aviation market, passenger comfort is paramount. In order to improve the vibration

comfort of civil aircraft and enhance the market competitiveness of Chinese civil aircraft, this article proposed

methods and ideas for solving civil aircraft vibration problems from the perspective of civil aircraft design process.

Firstly, based on the commercial operation of China′s domestically developed regional aircraft ARJ21 and large

aircraft C919 with independent intellectual property rights, the main vibration problems of China′s self-developed

civil aircraft were introduced in detail. Secondly, the multi-source vibration characteristics of civil aircraft and

their transmission paths on the body were analyzed, and the methods of multi-source vibration contribution analysis and cabin vibration comfort evaluation were introduced. Subsequently, in order to prioritize vibration comfort

requirements in the design phase of civil aircraft, a two-stage vibration reduction index allocation process based on

multi-source vibration contribution analysis was proposed, and the basic idea of civil aircraft vibration comfort design was constructed. Finally, the research direction of vibration comfort design for civil aircraft was prospected,

and the technical measures and ideas to improve passenger comfort were explored, in order to provide useful inspiration for the vibration comfort design of Chinese civil aircraft.

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Review of key technologies and methods for secure sharing of civil aviation data

DENG Wua , LI Xinyanb , ZHOU Xiangbing , ZHAO Huimina

Journal of Civil Aviation University of China 2025, 43 (2): 8-18.

Abstract （1894）

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This paper provides an in-depth analysis of the current research status and technological advancements in civil

aviation data sharing. Firstly, this article outlines the basic framework and core elements of civil aviation data sharing, followed by a detailed discussion of several cutting-edge technologies and their applications. Among them, the

system wide information management (SWIM) serves as the core platform supporting civil aviation data sharing, achieving comprehensive integration and efficient utilization of aviation data by building a unified information

exchange network. The collaborative decision making (CDM) system further strengthens real-time communication and collaboration across departments and institutions, particularly demonstrating significant results in areas of

flight operation management, optimal resource allocation and emergency response, which has effectively improved

the overall operational efficiency and safety of the civil aviation system. In terms of data security and privacy protection in data sharing, new technologies such as blockchain and federated learning have also shown great poten鄄

tial. Blockchain provides secure and transparent data sharing solutions, while federated learning achieves knowledge sharing under the premise of protecting privacy. However, data sharing faces challenges such as insufficient

standardization, difficulty in cooperation and coordination, data security, technical complexity, and cost feasibility.

In summary, this article not only reveals the latest technological advancements of key technologies for secure sharing of civil aviation data, but also provides a forward-looking perspective on future trends and opportunities, providing reference and guidance for the continuous innovation of civil aviation data sharing and the digital transformation of the global civil aviation industry.

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Research on evolution of air traffic flow fluctuations based on integration

encoding transition network

ZHANG Xie , ZHANG Jun , LIU Hongzhi , ZHAO Yifei

Journal of Civil Aviation University of China 2025, 43 (2): 19-30.

Abstract （1370）

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In order to break through the limitations of previous research that only focused on the direction of air traffic flow

fluctuations, and to fully highlight the actual operational information such as flow fluctuation status and airport capacity limitations in the study of air traffic flow dynamic evolution, a fusion encoding transition network construction method is proposed using dynamic coarse-grained encoding method to symbolically encode the airport flow

volume ratio and flow fluctuation gradient and merge into fluctuation modal. Quantitative analysis and qualitative

identification study are conducted on the evolution laws and characteristics of air traffic flow fluctuations from a

complex network perspective, focusing on the 24-hour and coordinated time periods of Beijing Daxing International Airport (Daxing Airport). The research results indicate that the differences in the evolution of air traffic flow

fluctuations between the two periods at Daxing Airport are mainly concentrated at the macro level. The evolution of

flow fluctuation modes has significant transfer aggregation and successive frequency, and there are significant frequent transfer modes. Strong clustering modes and large hub modes effectively characterize the trajectory characteristics of flow fluctuation evolution. These regular features provide a theoretical basis for predicting air traffic flow

fluctuations state and constructing flow management plans, which has practical significance for improving airport

capacity utilization efficiency and optimizing airport time resource allocation.

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Optimization of aircraft dynamic taxiing path

GAO Jinmin , LE Meilong , LI Xingcan

Journal of Civil Aviation University of China 2025, 43 (2): 31-37.

Abstract （1552）

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To reduce aircraft taxiing time and improve the efficiency of airport surface utilization, this paper establishes a

mixed integer linear programming model for aircraft dynamic taxiing. The model aims to minimize the total operating cost and is constrained by taxi safety intervals and conflict avoidance. The essence of the model belongs to the

dynamic traveling salesman problem (TSP). Therefore, computational experiments are conducted based on the scene

configuration data and 33 takeoff and landing flight data of Guangzhou Baiyun International Airport (Baiyun Airport). For the convenience of research, this article first applies graph theory processing to the physical scene to establish a graph theory model, using intersection points, endpoints, and segmentation points as points, and runway

and taxiway segmentation as edges. Based on the arrival (departure) situation, a directed graph is established to

ensure that the aircraft slides towards the parking position (runway). Special point designs have been adopted to

avoid conflicts with departing flights when handling runway crossings. In order to solve the problem using Cplex

optimizer, the model linearizes the nonlinear constraints. In order to verify the correctness of the model, a calculation experiment is conducted without considering conflicts to prove its ability to find the shortest path. Then, a time

stamp, i.e. a time window, was attached to perform calculation of dynamic optimization path to avoid conflicts. The

results indicate that the mixed integer linear programming model for aircraft dynamic taxiing can effectively obtain

the optimized path for dynamic takeoff and landing taxiing. In Baiyun Airport, the east-west separated operation,

i.e. the runway assignment "nearby mode", can be used for aircraft taxiing optimization scheduling

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Evaluation and prediction of runway roughness by pilots based on

BP neural network

QI Lin , LI Lingtong

Journal of Civil Aviation University of China 2025, 43 (2): 38-44.

Abstract （1586）

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Based on the survey data of subjective evaluation of runway roughness by pilots on 37 actual test runways, conducted by the Federal Aviation Administration (FAA) in B737-800 and A330-200 flightsimulators, the relationship between the evaluation indicators of runway roughness and pilots′ evaluations of runway roughness in China was analyzed, and the impact of different aircraft models on pilots′ evaluations of runway roughness were compared and analyzed. Back propagation (BP) neural network was built, the current runway roughness evaluation indicators in China and aircraft gross weight (AGW) were taken as the input, and the pilots′ acceptance of runway roughness were

taken as the output to predict the pilots′ evaluation of runway roughness. The results showed that the goodness of fit

between each runway roughness evaluation indicator and the pilot′s evaluation of runway roughness is low, making

it impossible to predict the pilots′ evaluation results separately. The aircraft type can affect the pilots′ evaluation of

runway roughness, and the characteristics of the aircraft type should be considered when the pilot evaluates and

predicts runway roughness. The BP neural network has a prediction accuracy of 100% in the training set and 95.5%

in the test set. It can effectively integrate the characteristics of China′s runway roughness evaluation indicators and

achieve accurate prediction of pilots′ runway roughness evaluation results across aircraft types.

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Study on the strength of frozen powdery clay and its influencing factors

in the Mohe region

QI Chunxiang, MA Jiahui, LU Weilong, ZHANG Kaiqiang, ZHAO Zhongtao

Journal of Civil Aviation University of China 2025, 43 (2): 45-51.

Abstract （1184）

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Permafrost is significantly affected by temperature and freeze-thaw cycles. In order to explore its mechanical properties, this paper takes frozen soil in Mohe area as the research object, and conducts direct shear tests of frozen soil

under different moisture content and freeze-thaw cycle times, as well as dynamic triaxial tests of frozen soil under

different temperature, moisture content, confining pressure, loading frequency, and freeze-thaw cycle times, to analyze the shear resistance characteristics and dynamic performance of frozen soil under different influencing factors. The experimental results indicate that the shear stress and shear displacement curves of frozen soil samples are

strain softening type. As the moisture content and freeze-thaw cycles increase, the shear strength, cohesion, and internal friction angle of frozen soil samples all decrease to varying degrees. The dynamic elastic modulus of frozen

soil samples varies within the range of 210-800 MPa in the experiment, which is positively correlated with moisture

content, freeze-thaw cycle times, and loading frequency, and negatively correlated with temperature and confining

pressure conditions, with the most significant change with moisture content. Meanwhile, based on the experimental

results, the formula for calculating the dynamic elastic modulus of frozen soil based on various influencing factors

are derived. The above research results can provide reference data on the mechanical properties of frozen soil for

airport construction and other engineering projects in the Mohe area.

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Analysis of factors affecting terminal safety resilience based on

DEMATEL-ISM model

SONG Yang a , WANG Ruiqi b , ZHANG Peng b

Journal of Civil Aviation University of China 2025, 43 (2): 52-57.

Abstract （1947）

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To promote the construction of terminal safety resilience and improve the level of terminal safety management, the

concept of "safety resilience" is introduced into terminal safety management, and the factors affecting the safety resilience of the terminal are analyzed using the integrated method of decision-making trial and evaluation laboratory

(DEMATEL) and interpretative structural model (ISM). Firstly, the definition of terminal safety resilience is proposed, and the indicator system of terminal safety resilience influencing factors is constructed centered on the monitoring ability, resistance ability, emergency response ability and recovery ability demonstrated with its operation.

Then, the DEMATEL-ISM model is established, and the DEMATEL method is used to calculate the degree of influence, the degree of being influenced, the degree of center, the degree of cause, and the causal attributes between

the factors, and the ISM method is used to divide their hierarchical structure. Finally, Terminal A of a domestic airport is taken as an example for model validation. The results indicate that the fundamental influencing factor of terminal safety resilience is the establishment of a terminal safety resilience mechanism, which is consistent with the

actual operation of Terminal A. This validates the effectiveness and reliability of the model and provides decision making and theoretical support for terminal safety management.

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Analysis of the influence of metal mesh structure parameters on lightning

protection effect of CFRP laminates

JIA Baohui a , LIU Xuyub , YANG Xiaob

Journal of Civil Aviation University of China 2025, 43 (2): 58-65.

Abstract （1136）

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To explore the influence of the geometric structure parameters of the metal mesh on its lightning protection ability, a

finite element model of carbon fiber reinforced composite (CFRP) laminates with different geometric structure parameters of the metal mesh protective layer was established. The thermal and electrical coupling analysis was used to

simulate the CFRP lightning ablation damage without protection, with aluminum mesh protection and with copper

mesh protection. CFRP ablation damage under copper mesh protection with different geometric structural parameters are compared and analysed. It is found that under the same geometric structure parameters, copper mesh has

better lightning protection effect than aluminum mesh. The geometric structure parameters of the metal mesh can

affect its lightning protection effect. The long and short intercept will affect the number of nodes of the metal mesh.

The lightning protection ability of the metal mesh will increase with the number of nodes. Increasing the width and

thickness of the wire can improve the lightning protection ability of the metal mesh, and the lightning protection ability improved by increasing the wire thickness is better than that by increasing the wire width. By comparing the

protective capability of copper mesh with different grid internal angles, it is found that 48° is the internal angle that

can relatively improve the lightning protection capability of metal mesh.

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Design and development of structural health management system for

passenger-to-cargo aircraft

LI Dinghea , GAO Boxiang b , WU Yaogang b

Journal of Civil Aviation University of China 2025, 43 (2): 66-72.

Abstract （1700）

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Passenger-to-cargo conversion is an effective way to cope with the volume growth of air cargo and the disposal of old

passenger aircraft. Passenger-to-cargo aircraft are mostly aged aircraft with serious structural damage problem,

thus the development of structural health management system has a very important engineering application value.

This paper combines the current situation of aircraft health management business in an MRO (maintenance, repair

and overhaul) enterprise and its own information development needs, based on an electronic prototype model of a

certain type passenger-to-cargo aircraft, a passenger-to-cargo aircraft structural health management system is designed and developed, providing an efficient processing and management platform for a large amount of structural

health data, implementing functions such as computer management of health management business, sharing and

communication of information resources, analysis and evaluation of typical injuries, etc. The finite element analysis

provides effective value for aircraft configuration management and health management.

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Two-level matching algorithm for image features based on CA-SIFT

JIAO Weidong, JIAO Yizhe

Journal of Civil Aviation University of China 2025, 43 (2): 73-82.

Abstract （1972）

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To address the problems of loss of image spectral information, low matching accuracy and large computational effort in the process of color image matching by the scale invariant feature transform (SIFT) algorithm in Euclidean

space, an image matching algorithm based on CA-SIFT is proposed using the expressiveness of Clifford algebra

(CA) for multidimensional space. Firstly, the image is transformed to CA space representation, while retaining the

image space and spectral information, and the metric function is constructed by the inner product operation of the

conformal geometric algebra to improve the efficiency of feature point search and detect feature points in CA space.

Secondly, a two-stage image feature matching strategy is adopted, the CA-SIFT feature description vector is converted into a hash code, and the coarse matching results are obtained by brute force matching. Finally, a gridbased motion statistics (GMS) method is used to complete the fine matching. The experimental results show that the

proposed algorithm outperforms the SIFT algorithm, and the number of extracted feature point pairs is improved

nearly 54%. In terms of image matching, the average matching accuracy reaches over 98%, achieving a highly accurate and applicable image matching method for most scenes.

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Research on the simulation platform for medium and large UAV based on Unity3D

SONG Yunxue, ZOU Zizhen

Journal of Civil Aviation University of China 2025, 43 (2): 83-88.

Abstract （1360）

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With the increasingly widespread application of medium and large unmanned aerial vehicle (UAV), their maintenance support and flight control capabilities are receiving growing attention from users. This article aims to address

the difficulties in practical maintenance of UAV and the low safety of flight control, taking the MQ-9 UAV as a case

and using the highly interactive and realistic Unity3D engine as a development tool, a visual simulation platform for

UAV is constructed to explore virtual maintenance and flight simulation methods. The results indicate that the interactive visualization feature of the simulation platform enables users to easily obtain the static and dynamic characteristics of the UAV maintenance system, timely provide geometric interference warnings between the maintenance personnel and the maintenance environment, verify the accuracy of maintenance and flight operations, and

achieve the goal of improving maintenance process cognition and flight operation skills.

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Evaluation of coupling coordination degree between China′s air transportation

industry and private economy from a multi-level perspective

LI Guodonga, , LIU Huijieb, , MEI Yuea,

Journal of Civil Aviation University of China 2025, 43 (2): 89-96.

Abstract （1293）

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To promote the coordinated development of China′s air transportation industry and the private economy, this study

employs the entropy weight method to construct a comprehensive evaluation model reflecting the coupled development level of air transportation industry and private economy and the coupling coordination degree is investigated

at national, regional, and provincial levels. The findings reveal that the coupling coordination degree between China′s air transport industry and private economy has steadily increased, gradually attaining high-quality coupling.

The coupling coordination degree between the two at the region level demonstrates polarization characteristics, with

East China exhibiting the highest coordination level, while the lowest in Northwest and Xinjiang regions. At the

provincial level, similar polarization patterns emerge: Guangdong and other provinces are categorized as "coordinated coupling zones", whereas Beijing and others fall into "uncoordinated and declining zones". Finally, corresponding rationalization suggestions are proposed based on research results at different levels.

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Experimental and simulation on emergency evacuation of passenger in wide-body aircraft under tilted attitude

CHENG Ming, WEI Keyu

Journal of Civil Aviation University of China 2025, 43 (3): 1-7.

Abstract （2249）

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To explore the influence of tilted attitude of wide-body aircraft on the emergency evacuation of cabin passenger, a

combination of cabin partial evacuation test and full-size simulation test is used to analyze the key factors such as

evacuation time. Based on the scenario construction theory and social force model, the relevant parameters in the

full-size simulation model are modified with real test data of partial evacuation, and then the full-size simulation

model is used to conduct the simulation test of passenger evacuation under cabin tilted attitude, and the increase

model of the average evacuation time of tilted attitude is established. The test data show that the inclination attitude

angle of the aircraft has an effect on the evacuation process and efficiency. Under pitch attitude, pitch ±5 degrees

has a positive effect on the evacuation efficiency, evacuation efficiency is -0.044 at pitch -10 degrees. Under

roll posture, roll angle has a significant negative correlation with evacuation efficiency, and the evacuation efficiency is -0.073 at roll ±10°. The results show that the data deviation between simulation model and real test of partial

evacuation is 6.54%, which is in the acceptable range. The full-size simulation model can accurately simulate the

effects and change rules of passenger emergency evacuation under the tilted attitude of the cabin, and can provide

references for the safety evaluation of the design, manufacture and operation of passenger aircraft.

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Research on risk factors analysis of civil aircraft landing gear retraction

system based on STPA

JIA Baohui a , WEN Xiaowei b , WANG Yiqianga , HAN Wenrui b , XIAO Haijianb

Journal of Civil Aviation University of China 2025, 43 (3): 8-14.

Abstract （1615）

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In this paper, based on system theoretic process analysis (STPA) method, the system level hazards of aircraft landing gear retraction system were identified and determined, and the behavior principle block diagram model of human-machine control, system functional action and feedback of the whole operation process of the system was constructed. The unsafe control action (UCA) in the operation process of the system was identified and the risk factors

leading to UCA were analyzed. The research showed that the method can not only enable identification of all component physical failure factors recognized by traditional safety analysis methods, but also identify risk factors leading to UCA incidents resulting from human-machine interaction, such as position and actuate on control unit

(PACU) core processor algorithm delays and crew member misoperation. The research results of this paper can

provide theoretical basis and methodological support for safety analysis of the entire process for civil aircraft development and application.

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Prediction method for bearing remaining life based on GMTCN model

GUO Runxiaa , JIANG Yuyanga , HUANG Chaob

Journal of Civil Aviation University of China 2025, 43 (3): 15-23.

Abstract （1492）

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Aiming at the problem that the existing prediction methods for bearing remaining life are difficult to effectively

extract degradation features when dealing with multi-sensor data, a prediction method for bearing remaining life

based on global attention and multi-scale time convolutional network (GMTCN) was proposed. Firstly, the GMTCN

model was used to process the multi-sensor signals of the bearing, and the degradation features of the bearing at

different scales were extracted with the help of two different strategies of temporal convolutional networks.

Secondly, the global attention mechanism was used to balance the contribution of data from different sensors and

time steps in the bearing remaining life prediction, and the extracted multi-scale features were fused. Finally, the

remaining life of the bearing is predicted. To assess the performance of this method, remaining life prediction were

conducted using the PHM2012 bearing dataset and a bearing dataset obtained from degradation data collected on

an accelerated fatigue testing platform. The root mean square error (RMSE) and mean absolute error (MAE) values

obtained were lower than other methods, while the average value of SCORE was increased to a certain extent,

proving the effectiveness of the method.

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Airspace capacity evaluation of wide range air route network based on

improved Euler model

GAO Wei, MU Rong

Journal of Civil Aviation University of China 2025, 43 (3): 24-31.

Abstract （1968）

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Aiming at the high complexity of airspace capacity evaluation of wide range air route network, a method for fast

evaluating airspace capacity of wide range air route network was proposed. Firstly, the airports, terminal areas and

sectors in the airspace were taken as nodes, and the network edge was determined according to whether there was

traffic flow between nodes. The airspace topology network of air route network based on airport, terminal areas and

sector nodes was obtained to reduce the airspace dimension of the air route network. Secondly, the airports, terminal

areas and sector nodes were used as the control unit of the Euler model to improve the Euler model, and the improved Euler model was used to model the traffic flow in the airspace topology network of the air route network.

Then, a target optimization model was established based on node capacity, and used elite retention genetic algorithm to solve the traffic flow in the airspace topology network of the air route network. When the traffic flow in the

airspace topology network of the air route network stabilizes, the airspace capacity of the air route network was obtained. Finally, the airspace capacity of a certain air route network was calculated in China and conducted simulation verification using total airspace and airport modeller (TAAM), proving the feasibility and accuracy of this

method.

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Design of aircraft cabin passenger layout scheme based on infectious disease model

GU Runping, ZHANG Yangzong, LIU Jiaming

Journal of Civil Aviation University of China 2025, 43 (3): 32-37.

Abstract （2116）

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During the spread of the epidemic, regarding the risk of passengers of mutual infection in the aircraft cabin, it is

very necessary to optimize the layout scheme of passengers in the cabin and reduce the virus infection probability of

passenger. By studying the law of virus transmission in the aircraft cabin, this paper analyzed the influencing

factors of the probability of individuals being infected by the virus and the virus shedding rate in the cabin. The

match between passenger and seat was used as the decision variable, and the minimum sum of the cabin passengers

affected by the virus shedding rate of other passengers around was used as the objective function. Based on the

characteristics of passenger group flight, a allocation model for the passenger group cabin seat was established. This

paper designed an improved genetic algorithm, solved the model, and realized the algorithm using Matlab. Taking

A320 aircraft as an example, three passenger cases with different group layouts were tested. The results showed that

the proposed model and algorithm can provide an optimized seat allocation scheme within an acceptable time and

reduce the probability of infection among passengers.

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A runway icing prediction method based on physics-informed neural network

XING Xinyuana, b , LIU Shifua, b , LING Jianminga, b , TAO Zefenga, b,

Journal of Civil Aviation University of China 2025, 43 (3): 38-44.

Abstract （1783）

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Runway icing poses a threat to the safety of aircraft ground operation, accurate prediction of pavement temperature

and icing state is essential. To overcome the limitations of traditional runway icing predication methods in handling

complex scenarios, limited data, and physical inconsistency, this study proposes a runway icing prediction method

based on physics-informed neural network (PINN). The model embeds multilayer structure heat conduction and

water-ice phase change mechanisms into a deep neural network, enabling precise prediction of temperature fields

and water-ice state under limited data. Experimental data from a self-designed icing simulation are used to compare the solution results of PINN with the finite difference method (FDM). Results show that the jointly driven data physics PINN reduces average prediction error of temperature by about 90% compared to FDM, with just 0.21 ℃,

which is able to reconstruct full-field temperature field from limited data. Furthermore, the study analyzes the

mechanisms of salinity lowers the freezing point, delays icing, and suppresses ice growth. These findings can provide a new technological path for runway icing prediction.

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Study on the vibration effects of localizer antenna array ca

CHEN Yiting, YANG Jizhong, FENG Dubei, LIU Fangbo, LIU Jian, JIN Xuwei

Journal of Civil Aviation University of China 2025, 43 (3): 45-52.

Abstract （1360）

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This study employs a combined approach of field modal testing and dynamic simulation to comprehensively analyze

the vibration effects of a 350 km/h high-speed operation railway crossing airport flight area on the localizer (LOC)

antenna array. The results indicate that under the effect of vehicle -induced vibration, the LOC antenna array

exhibits the most significant vibration in the vertical direction, followed by the cross-track direction, with minimal

impact observed in the along-track direction. As tunnel burial depth increases, the vibration responses of the LOC

antenna array progressively diminish, particularly showing the most pronounced attenuation in vertical vibration.

LOC antenna array is prone to resonance phenomena at a frequency of 37.70 Hz. Within the 0-40 m range from the

high-speed railway centerline, both equipment rooms and the LOC antenna array display rapid attenuation of peak

vibration acceleration, while beyond 40 m, the attenuation rate gradually slows. To meet navigation equipment

vibration protection standards, it is recommended to maintain a minimum distance of 60 m between the LOC

antenna array and the high-speed railway centerline when high-speed railway crossing airport flight areas.

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Network resilience assessment of airport running and sliding system based

on cell transmission model

ZHANG Yuhui, WEN Wen

Journal of Civil Aviation University of China 2025, 43 (3): 53-61.

Abstract （1966）

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Runway capacity is one of the key elements that affect the normal operation of airport flight areas, and external disturbance events can cause a decrease in the dynamic capacity of the airport. According to airport aircraft taxiing

rules, this article proposes a model to evaluate the resilience of airport flight area operation network after disturbance events, based on cell transmission model (CTM). Firstly, network performance parameters are obtained

based on the CTM. Then, taking the number of aircraft waiting in the network and the efficiency of network operation as basic performance indicators, a resilience index for the dynamic changes of the resilience of the disturbed

network is established. Finally, the CTM based network resilience assessment framework for airport running and

sliding system is established, and operational data from Tianjin Binhai International Airport in 2019 are collected,

processed, and analyzed. The research results indicate that the trend of simulated airport departure operation data

is highly consistent with the actual departure operation data, with a simulation accuracy of over 90%, and can accurately describe the network traffic flow distribution of the airport running and sliding system. The two proposed resilience assessment indicators for airports can comprehensively reflect the complete dynamic change process of

system network performance from degradation to recovery before and after disturbance events occur, providing new

support for network management of airport running and sliding system.

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Research on real-time sensing model of aircraft wheel load on

airport rigid pavement

ZHANG Xianmin, CHEN Yuxiang, ZHANG Yuhui

Journal of Civil Aviation University of China 2025, 43 (3): 62-67.

Abstract （1439）

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To explore the transfer relationship between the single wheel load applied on the surface layer of airport rigid pavement and the perceived load on the base top, and provide theoretical basis and reference for the inverse calculation

of this process, firstly, a three-dimensional finite element model of the airport rigid pavement was established using

ABAQUS software. Secondly, taking B737-800 as an example, the influence of changes in runway structural parameters on the transmission process under different load capacities was calculated. Finally, different aircraft load

conditions were designed for different landing gear types, and the load transfer process was compared between

those with the same landing gear type but different landing gear spacing and those with different landing gear types

but similar landing gear spacing. The calculation results showed that the cushion layer elastic modulus and the surface layer thickness have the most significant impact on the load transfer process. Under different conditions of

cushion layer elastic modulus and surface layer thickness, the maximum difference in perceived load at the top of

the foundation was 20.36% and 8.49%, respectively. When the single wheel load is fixed and the form of the main

landing gear wheel group is the same, the perceived load at the base top decreases with the increase of the main

landing gear spacing. When the load superposition of the main landing gear wheel group on the other side is weak

enough to be ignored, the load sensing relationship was basically the same under different wheel group configuration.

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Hierarchical gas deduction method based on Wasm code block

FENG Xia, ZHAO Meng, LIU Caihua

Journal of Civil Aviation University of China 2025, 43 (3): 68-74.

Abstract （1770）

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Aiming at the problem of long latency in the process of gas deduction of blockchain smart contract virtual machine

based on WebAssembly (Wasm), the performance bottleneck in the process is analyzed, and a hierarchical gas deduction method based on code blocks is proposed. By designing instruction recorder and code block analyzer in

Wasm virtual machine, gas deduction based on code block is implemented. According to the structure of Wasm

module, hierarchical code block recognition rules are designed. The experimental results show that, compared with

the traditional instruction-by-instruction gas deduction method, the proposed method reduces the number of gas

deduction by 79.6%, and the execution average latency can be reduced by 17.0% and 18.8% in serial and parallel

transaction execution modes, respectively

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Separating ADS-B signal with unknown interweaving multiplicity

using DPRNN

WANG Wenyi, WANG Jianshe

Journal of Civil Aviation University of China 2025, 43 (3): 75-80.

Abstract （1287）

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The interweaving of multiple signals is an inevitable problem in automatic dependent surveillance -broadcast

(ADS-B) system. Existing single-antenna ADS-B signal de-interweaving methods mostly require accurate estimation of parameters such as the interweaving multiplicity and relative delay, and the estimation accuracy often seriously affects the final separation performance. To address this problem, this paper uses dual-path recurrent neural

network (DPRNN) to separate ADS-B reception signals without the need to estimate any parameters. The network input is ADS-B signals with unknown interweaving multiplicity, including pure noise signal, no interweaving

signal, double interweaving signal and triple interweaving signal. The network is fixed to output three signals, and

when the interweaving signal contains i ADS-B signals, the corresponding source signals have i ADS-B signals

and (3 - i) noise signals. Simulation experiments show that the separation accuracy is above 95% when the interweaving multiplicity is no more than three. This study provides a new solution for ADS-B signal interweaving separation, which has practical value.

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Analysis of rotor aerodynamic disturbance in cruising state of quad tilting rotor UAV

YANG Yonggang a , QIU Mingzhi b

Journal of Civil Aviation University of China 2025, 43 (3): 81-85.

Abstract （1841）

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In order to explore the aerodynamic change law of a certain type of quad tilting rotor unmanned aerial vehicle (UAV)

during high-speed cruising process, the multiple reference frame (MRF) numerical simulation method is used to

analyze the quad tilting rotor UAV model established in this paper. By changing the relative thickness of the wing

airfoil, rotor collective pitch, forward flight speed and other parameters, the whole aircraft disturbance of the UAV

model is simulated, and the aerodynamic change characteristics of components such as rotors are analyzed. The results show that increasing the relative thickness of the wing airfoil can reduce the pull coefficient of rear rotor during cruise process, When the thickness increases by 6%, the tensile coefficient decreases by 17.09%. At the same

time, under the superposition of the front intake air flow and the front rotor slip flow, the front rotor slip flow will

have a certain impact on the rear rotor aerodynamic performance, and as the forward flight speed increases, the impact of the front rotor slip flow will first increase and then weaken.

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Research progress on preparation of phosphating film on magnesium

alloys surface

TONG Xiaoqiang , WANG Ruijue, , JIN Shenglong

Journal of Civil Aviation University of China 2025, 43 (3): 86-96.

Abstract （1345）

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Phosphating is an important technological process for enhancing corrosion resistance of magnesium alloys. The

preparation of phosphating films takes the interface of the alloy/solution as place, coupling multiple physical,

chemical, and electrochemical processes. Firstly, this paper commences with the kinetics of phosphating to summarize the recent research of preparations of phosphating film on magnesium alloys surface and divides the phosphating process into three consecutive sub-processes: the electrochemical corrosion of the substrate, the reaction

and diffusion of ions at the alloy/solution interface, and the heterogeneous crystallization of the phosphating film.

Secondly, in chronological order, the role of synthesis parameters in phosphating regulation is analyzed to clarify

the influence of various factors on the phosphating of magnesium alloys. It is concluded that the self-coupling of

multiple factors such as temperature, substrate treatment methods, pH, etc., and the multiple cross-couplings with

the three phosphating sub-processes are the difficulties in understanding the formation mechanism of the phosphating film. Finally, the research direction on the preparation of phosphating films on the surface of magnesium

alloys are prospected.

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Research on lumbar spine injury of aircraft occupants under vertical impact

based on THUMS

SHI Xiaopenga , LI Peiyaob , GUO Kai c , CUI Shurui c , XIE Jianga

Journal of Civil Aviation University of China 2025, 43 (4): 1-9.

Abstract （2390）

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Under aircraft crash impacts, lumbar spine injury is a key factor affecting the survival ability of aircraft occupants

(abbreviated as occupants). This article aims to investigate the lumbar spine injuries of occupants under vertical

impact loads. Firstly, the high-precision numerical dummy THUMS (total human model for safety) was used to

study the effects of loading peak and loading time of the impact load acceleration on the biomechanical injuries

to the lumbar spine of occupants. Secondly, the differences in lumbar spine dynamic response between THUMS

and Hybrid Ⅲ dummies under vertical impact conditions were analyzed. Finally, the biomechanical injury of the

occupants′ lumbar spine was studied from a microscopic perspective. The study showed that with change of constant velocity, the peak value of axial load of the occupants′ lumbar spine increases greatly with an increase in

loading peak of acceleration, while the peak value of bending moment of the lumbar spine increases little. The

peak value of axial load of the occupants′ lumbar spine is positively correlated with the speed of energy accumulation. When the loading time is excessively short, the inertia effect limits lumbar flexion, resulting in a smaller

bending moment of the lumbar spine. The largest axial load of lumbar spine appears at the L5 cross-section and

the largest bending moment of lumbar spine occurs at the L1 cross-section, the assessment of lumbar spine injury

of occupants should comprehensively consider the effects of axial compression force and bending moment. From

a biomechanical perspective, the risk of injury to the cortical bone and key ligaments of the lumbar spine is the highest.

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Research progress on the application of CF3I in substituting airborne Halon

fire-extinguishing agent

CUI Wenyao

Journal of Civil Aviation University of China 2025, 43 (4): 10-14.

Abstract （2050）

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The airborne Halon fire-extinguishing agent in aircraft has been restricted in production and phased out within a

specified period by international conventions due to its ozone depleting effects. Trifluoroiodomethane (CF3I) is

considered as one of the most promising Halon alternatives due to its comparable efficiency of fire-extinguishing

to Halon, low ozone depletion potential (ODP) and global warming potential (GWP). However, concerns regarding

its cardiac sensitization have limited its usage to uninhabited areas. In this work, the feasibility study of CF3I replacing airborne Halon fire-extinguishing agent is firstly sorted out. Then, the current research progress on the

design of CF3I fire-extinguishing system is summarized. Finally, the research direction of airborne CF3I fire-extinguishing device is prospected. This study has important practical significance for the research and development

of domestic large aircraft Halon replacement technology and fire-extinguishing equipment.

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