From arsenal delivery to rescue missions, unmanned aerial vehicles (UAVs) are playing a crucial role in various fields, which brings the need for continuous evolution of system identification techniques to develop sophisticated mathematical models for effective flight control. In this paper, a novel parameter estimation technique based on filter error method (FEM) augmented with particle swarm optimisation (PSO) is developed and implemented to estimate the longitudinal and lateral-directional aerodynamic, stability and control derivatives of fixed-wing UAVs. The FEM used in the estimation technique is based on the steady-state extended Kalman filter, where the maximum likelihood cost function is minimised separately using a randomised solution search algorithm, PSO and the proposed method is termed FEM-PSO. A sufficient number of compatible flight data sets were generated using two cropped delta wing UAVs, namely CDFP and CDRW, which are used to analyse the applicability of the proposed estimation method. A comparison has been made between the parameter estimates obtained using the proposed method and the computationally intensive conventional FEM. It is observed that most of the FEM-PSO estimates are consistent with wind tunnel and conventional FEM estimates. It is also noticed that estimates of crucial aerodynamic derivatives ${C_{{L_alpha }}},;{C_{{m_alpha }}},;{C_{{Y_beta }}},;{C_{{l_beta }}}$ and ${C_{{n_beta }}}$ obtained using FEM-PSO are having relative offsets of 2.5%, 1.5%, 6.5%, 3.4% and 7.6% w.r.t. wind tunnel values for CDFP, and 1.4%, 1.9%, 0.1%, 9.6% and 7.5% w.r.t. wind tunnel values for CDRW. Despite having slightly higher Cramer-Rao Lower Bounds of estimated aerodynamic derivatives using the FEM-PSO method, the simulated responses have a relative error of less than 0.10% w.r.t. measured flight data. A proof-of-match exercise is also conducted to ascertain the efficacy of the estimates obtained using the proposed method. The degree of effectiveness of the FEM-PSO method is comparable with conventional FEM.
从军火库运送到救援任务，无人机在各个领域发挥着至关重要的作用，这就需要不断发展系统识别技术，以开发有效飞行控制的复杂数学模型。提出并实现了一种基于滤波误差法(FEM)和粒子群优化(PSO)的参数估计方法，用于估计固定翼无人机的纵向和横向气动导数、稳定性和控制导数。在估计技术中使用的FEM是基于稳态扩展卡尔曼滤波器，其中最大似然代价函数分别极小化使用随机解搜索算法，PSO和所提出的方法被称为FEM-PSO。使用两种裁剪三角翼无人机(CDFP和CDRW)生成了足够数量的兼容飞行数据集，用于分析所提出的估计方法的适用性。用该方法得到的参数估计与计算量大的传统有限元法进行了比较。结果表明，大多数有限元-粒子群算法的估算值与风洞和常规有限元估算值一致。还注意到，使用FEM-PSO获得的关键气动导数${C_{{L_alpha }}},;{C_{{m_alpha }}},;{C_{{Y_beta }}},;{C_{{l_beta }}}$和${C_{{n_beta }}}$的估计具有2.5的相对偏移%, 1.5%, 6.5%, 3.4% and 7.6% w.r.t. wind tunnel values for CDFP, and 1.4%, 1.9%, 0.1%, 9.6% and 7.5% w.r.t. wind tunnel values for CDRW. Despite having slightly higher Cramer-Rao Lower Bounds of estimated aerodynamic derivatives using the FEM-PSO method, the simulated responses have a relative error of less than 0.10% w.r.t. measured flight data. A proof-of-match exercise is also conducted to ascertain the efficacy of the estimates obtained using the proposed method. The degree of effectiveness of the FEM-PSO method is comparable with conventional FEM.
{"title":"Parametric model identification of delta wing UAVs using filter error method augmented with particle swarm optimisation","authors":"J. Samuel J, N. Kumar, S. Saderla, Y. Kim","doi":"10.1017/aer.2022.100","DOIUrl":"https://doi.org/10.1017/aer.2022.100","url":null,"abstract":"\u0000 From arsenal delivery to rescue missions, unmanned aerial vehicles (UAVs) are playing a crucial role in various fields, which brings the need for continuous evolution of system identification techniques to develop sophisticated mathematical models for effective flight control. In this paper, a novel parameter estimation technique based on filter error method (FEM) augmented with particle swarm optimisation (PSO) is developed and implemented to estimate the longitudinal and lateral-directional aerodynamic, stability and control derivatives of fixed-wing UAVs. The FEM used in the estimation technique is based on the steady-state extended Kalman filter, where the maximum likelihood cost function is minimised separately using a randomised solution search algorithm, PSO and the proposed method is termed FEM-PSO. A sufficient number of compatible flight data sets were generated using two cropped delta wing UAVs, namely CDFP and CDRW, which are used to analyse the applicability of the proposed estimation method. A comparison has been made between the parameter estimates obtained using the proposed method and the computationally intensive conventional FEM. It is observed that most of the FEM-PSO estimates are consistent with wind tunnel and conventional FEM estimates. It is also noticed that estimates of crucial aerodynamic derivatives \u0000 \u0000 \u0000 ${C_{{L_alpha }}},;{C_{{m_alpha }}},;{C_{{Y_beta }}},;{C_{{l_beta }}}$\u0000 \u0000 and \u0000 \u0000 \u0000 ${C_{{n_beta }}}$\u0000 \u0000 obtained using FEM-PSO are having relative offsets of 2.5%, 1.5%, 6.5%, 3.4% and 7.6% w.r.t. wind tunnel values for CDFP, and 1.4%, 1.9%, 0.1%, 9.6% and 7.5% w.r.t. wind tunnel values for CDRW. Despite having slightly higher Cramer-Rao Lower Bounds of estimated aerodynamic derivatives using the FEM-PSO method, the simulated responses have a relative error of less than 0.10% w.r.t. measured flight data. A proof-of-match exercise is also conducted to ascertain the efficacy of the estimates obtained using the proposed method. The degree of effectiveness of the FEM-PSO method is comparable with conventional FEM.","PeriodicalId":22567,"journal":{"name":"The Aeronautical Journal (1968)","volume":"202 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-01-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73212714","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
For a hypersonic-speed aircraft with a flat fuselage structure that has narrow space for a traditional wheel-type landing gear retraction, a novel type of wheel-ski landing gear is designed, which is different from traditional landing gears in force distribution and actuation methods. In order to capture the direction control performance of an aircraft with the wheel-ski landing gear, the aircraft ground taxiing nonlinear dynamic mathematical model is built based on a certain type of aircraft data. The experiment of the wheel-ski landing gear actuator and the differential brake control system is carried out to verify that the electric wheel-ski actuator model with the pressure sensor is in good agreement with the test results, indicating the model validity and the speediness of the differential brake response. Then a new fuzzy combined direction rectifying control law is designed based on the optimisation method and the fuzzy control theory. Comparing with the PD wheel-ski differential brake control, the direction rectifying efficiencies increase higher than 140% during the whole taxiing process. In addition, the combined control law can also decrease the overshoots of the yaw angle responses effectively. Finally, the stability and robustness of the designed combined direction control law are verified under various working conditions.
{"title":"Design and Performance of Directional Rectification Control System in an Aircraft with a Novel Type of Wheel-Ski Landing Gear","authors":"Q. Yin, H. Sun, Tao Li, X. Wei, J. Song","doi":"10.1017/aer.2022.83","DOIUrl":"https://doi.org/10.1017/aer.2022.83","url":null,"abstract":"\u0000 For a hypersonic-speed aircraft with a flat fuselage structure that has narrow space for a traditional wheel-type landing gear retraction, a novel type of wheel-ski landing gear is designed, which is different from traditional landing gears in force distribution and actuation methods. In order to capture the direction control performance of an aircraft with the wheel-ski landing gear, the aircraft ground taxiing nonlinear dynamic mathematical model is built based on a certain type of aircraft data. The experiment of the wheel-ski landing gear actuator and the differential brake control system is carried out to verify that the electric wheel-ski actuator model with the pressure sensor is in good agreement with the test results, indicating the model validity and the speediness of the differential brake response. Then a new fuzzy combined direction rectifying control law is designed based on the optimisation method and the fuzzy control theory. Comparing with the PD wheel-ski differential brake control, the direction rectifying efficiencies increase higher than 140% during the whole taxiing process. In addition, the combined control law can also decrease the overshoots of the yaw angle responses effectively. Finally, the stability and robustness of the designed combined direction control law are verified under various working conditions.","PeriodicalId":22567,"journal":{"name":"The Aeronautical Journal (1968)","volume":"107 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-01-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77160428","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The need for innovative solutions to enable aerial platforms to fly faster, higher, and longer continues to remain a primary focus for airframe designers. This paper outlines work undertaken to apply a morphing wing warping technology onto a generic Unmanned Aerial Vehicle to deliver enhanced flight performance, efficiency and control capabilities. The prototype employs wings of novel construction which provide both near resistance-free compliance in twist as well as adequate structural stiffness to resist applied loads; all while preserving an aerodynamically smooth surface. Used in combination with developed and integrated closed-loop feedback control architecture, a real-time, non-linear, span-wise wing twist adjustment capability required for optimised flight under differing operating conditions and flight requirements, is demonstrated. Experimental results obtained from a wind tunnel test program show up to a 72% increase in lift to drag ratio under certain conditions compared to a fixed baseline providing some confidence that the combination could be used to realise a step change in flight performance.
{"title":"Development of a morphing UAV for optimal multi-segment mission performance","authors":"A. Gatto","doi":"10.1017/aer.2022.99","DOIUrl":"https://doi.org/10.1017/aer.2022.99","url":null,"abstract":"\u0000 The need for innovative solutions to enable aerial platforms to fly faster, higher, and longer continues to remain a primary focus for airframe designers. This paper outlines work undertaken to apply a morphing wing warping technology onto a generic Unmanned Aerial Vehicle to deliver enhanced flight performance, efficiency and control capabilities. The prototype employs wings of novel construction which provide both near resistance-free compliance in twist as well as adequate structural stiffness to resist applied loads; all while preserving an aerodynamically smooth surface. Used in combination with developed and integrated closed-loop feedback control architecture, a real-time, non-linear, span-wise wing twist adjustment capability required for optimised flight under differing operating conditions and flight requirements, is demonstrated. Experimental results obtained from a wind tunnel test program show up to a 72% increase in lift to drag ratio under certain conditions compared to a fixed baseline providing some confidence that the combination could be used to realise a step change in flight performance.","PeriodicalId":22567,"journal":{"name":"The Aeronautical Journal (1968)","volume":"12 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-01-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79230761","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This study addresses orbit design and optimisation for the situation of satellite interception in which the target spacecraft is capable of manoeuvring using continuous magnitude restricted thrust. For the purpose of designing a long-range continuous thrust interception orbit, the orbit motion equations of two satellites with J2 perturbation are constructed. This problem is assumed to be a typical pursuit-evasion problem in differential game theory; using boundary constraint conditions and a performance index function that includes time and fuel consumption, the saddle point solution corresponding to the bilateral optimal is derived, and then this pursuit-evasion problem is transformed into a two-point boundary value problem. A hybrid optimisation method using a genetic algorithm (GA) and sequential quadratic programming (SQP) is derived to obtain the optimal control strategy. The proposed model and algorithm are proved to be feasible for the given simulation cases.
{"title":"A hybrid optimisation method for intercepting satellite trajectory based on differential game","authors":"W. Wu, J. Chen, J. Liu","doi":"10.1017/aer.2022.102","DOIUrl":"https://doi.org/10.1017/aer.2022.102","url":null,"abstract":"\u0000 This study addresses orbit design and optimisation for the situation of satellite interception in which the target spacecraft is capable of manoeuvring using continuous magnitude restricted thrust. For the purpose of designing a long-range continuous thrust interception orbit, the orbit motion equations of two satellites with J2 perturbation are constructed. This problem is assumed to be a typical pursuit-evasion problem in differential game theory; using boundary constraint conditions and a performance index function that includes time and fuel consumption, the saddle point solution corresponding to the bilateral optimal is derived, and then this pursuit-evasion problem is transformed into a two-point boundary value problem. A hybrid optimisation method using a genetic algorithm (GA) and sequential quadratic programming (SQP) is derived to obtain the optimal control strategy. The proposed model and algorithm are proved to be feasible for the given simulation cases.","PeriodicalId":22567,"journal":{"name":"The Aeronautical Journal (1968)","volume":"3 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-01-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81731173","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
C.-Q. Yan, Y.-C. Sun, X. Zhang, H. Mao, J.-Y. Jiang
Abstract This paper studied the use of eye movement data to form criteria for judging whether pilots perceive emergency information such as cockpit warnings. In the experiment, 12 subjects randomly encountered different warning information while flying a simulated helicopter, and their eye movement data were collected synchronously. Firstly, the importance of the eye movement features was calculated by ANOVA (analysis of variance). According to the sorting of the importance and the Euclidean distance of each eye movement feature, the warning information samples with different eye movement features were obtained. Secondly, the residual shrinkage network modules were added to CNN (convolutional neural network) to construct a DRSN (deep residual shrinkage networks) model. Finally, the processed warning information samples were used to train and test the DRSN model. In order to verify the superiority of this method, the DRSN model was compared with three machine learning models, namely SVM (support vector machine), RF (radom forest) and BPNN (backpropagation neural network). Among the four models, the DRSN model performed the best. When all eye movement features were selected, this model detected pilot perception of warning information with an average accuracy of 90.4%, of which the highest detection accuracy reached 96.4%. Experiments showed that the DRSN model had advantages in detecting pilot perception of warning information.
{"title":"A methodology to detect pilot perception of warning information by eye movement data and deep residual shrinkage networks","authors":"C.-Q. Yan, Y.-C. Sun, X. Zhang, H. Mao, J.-Y. Jiang","doi":"10.1017/aer.2022.101","DOIUrl":"https://doi.org/10.1017/aer.2022.101","url":null,"abstract":"Abstract This paper studied the use of eye movement data to form criteria for judging whether pilots perceive emergency information such as cockpit warnings. In the experiment, 12 subjects randomly encountered different warning information while flying a simulated helicopter, and their eye movement data were collected synchronously. Firstly, the importance of the eye movement features was calculated by ANOVA (analysis of variance). According to the sorting of the importance and the Euclidean distance of each eye movement feature, the warning information samples with different eye movement features were obtained. Secondly, the residual shrinkage network modules were added to CNN (convolutional neural network) to construct a DRSN (deep residual shrinkage networks) model. Finally, the processed warning information samples were used to train and test the DRSN model. In order to verify the superiority of this method, the DRSN model was compared with three machine learning models, namely SVM (support vector machine), RF (radom forest) and BPNN (backpropagation neural network). Among the four models, the DRSN model performed the best. When all eye movement features were selected, this model detected pilot perception of warning information with an average accuracy of 90.4%, of which the highest detection accuracy reached 96.4%. Experiments showed that the DRSN model had advantages in detecting pilot perception of warning information.","PeriodicalId":22567,"journal":{"name":"The Aeronautical Journal (1968)","volume":"1 1","pages":"1219 - 1233"},"PeriodicalIF":0.0,"publicationDate":"2023-01-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88140546","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
J. A. Flores-Mezarina, P. D. Bravo-Mosquera, D. Garcia-Ribeiro, H. Cerón-Muñoz
The wavy leading edge (WLE, also known as leading edge protuberances) is a passive flow control device inspired by the humpback whale pectoral flippers. It reduces the flow of three-dimensional effects on wings and increases their aerodynamic performance at high angles of attack. Despite the numerous studies on its aerodynamic benefits, research on its possible applications is still incipient. Therefore, this article addresses an evaluation of the WLE effects on the aerodynamic performance of a winglet. A rectangular wing, a base smooth leading edge winglet, and a winglet with WLE were designed and manufactured for CFD simulations and wind tunnel measurements. The winglet with WLE increased the maximum aerodynamic efficiency, i.e. this configuration reduced the induced drag by increasing wingtip vortex dissipation at a given angle-of-attack. Such results were used in re-evaluations of the aerodynamic performance of an original agricultural aircraft initially configured with a multi-winglet device. The winglet with WLE showed to be effective at increasing the aircraft operational time and range under a simulated actual condition.
{"title":"Application of wavy leading edge to enhance winglet aerodynamic performance","authors":"J. A. Flores-Mezarina, P. D. Bravo-Mosquera, D. Garcia-Ribeiro, H. Cerón-Muñoz","doi":"10.1017/aer.2022.97","DOIUrl":"https://doi.org/10.1017/aer.2022.97","url":null,"abstract":"\u0000 The wavy leading edge (WLE, also known as leading edge protuberances) is a passive flow control device inspired by the humpback whale pectoral flippers. It reduces the flow of three-dimensional effects on wings and increases their aerodynamic performance at high angles of attack. Despite the numerous studies on its aerodynamic benefits, research on its possible applications is still incipient. Therefore, this article addresses an evaluation of the WLE effects on the aerodynamic performance of a winglet. A rectangular wing, a base smooth leading edge winglet, and a winglet with WLE were designed and manufactured for CFD simulations and wind tunnel measurements. The winglet with WLE increased the maximum aerodynamic efficiency, i.e. this configuration reduced the induced drag by increasing wingtip vortex dissipation at a given angle-of-attack. Such results were used in re-evaluations of the aerodynamic performance of an original agricultural aircraft initially configured with a multi-winglet device. The winglet with WLE showed to be effective at increasing the aircraft operational time and range under a simulated actual condition.","PeriodicalId":22567,"journal":{"name":"The Aeronautical Journal (1968)","volume":"30 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-01-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90947980","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This online collection commemorates 75 years of aerospace engineering teaching and research at the University of Bristol. However, interactions with the aircraft industry started long before the Department was formed in 1946 [1], for instance when in 1918 the University began teaching a class in Aircraft Manufacturing. An early graduate of University of Bristol Engineering was Leslie Frise, who was hired by the Bristol Aeroplane Company to assist Chief Designer Frank Barnwell. Among accomplishments in his career, Frise designed the Type 156 Bristol Beaufighter, the Bristol Fighter in 1916 and the Bulldog in 1927. His most lasting contribution was the invention of the Frise Aileron, popular on many older aircraft, such as the Piper Cub, a major pre-WWII trainer in the USA. Frise took over as Chief Designer from Barnwell in 1936 and then became Chief Engineer after Barnwell’s death. Another significant graduate from the pre-department years was Archibald Russell. He was appointed Chief Designer of Bristol Aeroplane Company in 1946, becoming a leading structures expert and, eventually, Managing Director and then Chairman at British Aircraft Corporation Filton. In June 1945, at the end of the second world war, the Bristol Aeroplane Company offered to fund a Chair in Aeronautical Engineering at the University [2]. Sir Alfred Pugsley, who had been the distinguished Head of Structural Engineering at the Royal Aircraft Establishment (RAE) Farnborough had just taken up the chair of Civil Engineering at Bristol. He persuaded Roderick Collar, a mathematician and engineer with whom he had worked closely with at the RAE during the war, to apply and he was appointed as the first holder of the Sir George White Chair [2]. The first six undergraduates arrived in October 1946 and graduated in 1948.
这个在线收藏是为了纪念布里斯托尔大学75年的航空航天工程教学和研究。然而，早在1946年该系成立之前，与飞机工业的互动就开始了[1]，例如，1918年大学开始教授飞机制造课程。莱斯利·弗里斯是布里斯托尔工程大学的早期毕业生，他受雇于布里斯托尔飞机公司，协助首席设计师弗兰克·巴恩韦尔。在他的职业生涯中，弗里斯设计了156型布里斯托尔美丽战斗机，1916年的布里斯托尔战斗机和1927年的斗牛犬。他最持久的贡献是发明了旋翼副翼，在许多老式飞机上很受欢迎，比如美国二战前的主要教练机Piper Cub。弗里斯于1936年接替巴恩韦尔担任首席设计师，并在巴恩韦尔去世后成为首席工程师。另一位重要的系前毕业生是阿奇博尔德·罗素。1946年，他被任命为布里斯托尔飞机公司的首席设计师，成为领先的结构专家，并最终成为英国菲尔顿飞机公司的总经理和董事长。1945年6月，在第二次世界大战结束时，布里斯托尔飞机公司提出资助该大学航空工程教授[2]。阿尔弗雷德·帕格斯利爵士，曾是范堡罗皇家飞机公司(RAE)杰出的结构工程主管，刚刚担任布里斯托尔大学土木工程系主任。他说服了数学家、工程师罗德里克·科勒(Roderick Collar)向他提出申请，并被任命为乔治·怀特爵士(Sir George White)的首任主席[2]。科勒在战争期间曾与他在英国皇家研究学院(RAE)密切合作。首批六名本科生于1946年10月抵达，1948年毕业。
{"title":"Preview of the 75th Anniversary of aerospace engineering at the University of Bristol online collection","authors":"J. Cooper","doi":"10.1017/aer.2022.103","DOIUrl":"https://doi.org/10.1017/aer.2022.103","url":null,"abstract":"This online collection commemorates 75 years of aerospace engineering teaching and research at the University of Bristol. However, interactions with the aircraft industry started long before the Department was formed in 1946 [1], for instance when in 1918 the University began teaching a class in Aircraft Manufacturing. An early graduate of University of Bristol Engineering was Leslie Frise, who was hired by the Bristol Aeroplane Company to assist Chief Designer Frank Barnwell. Among accomplishments in his career, Frise designed the Type 156 Bristol Beaufighter, the Bristol Fighter in 1916 and the Bulldog in 1927. His most lasting contribution was the invention of the Frise Aileron, popular on many older aircraft, such as the Piper Cub, a major pre-WWII trainer in the USA. Frise took over as Chief Designer from Barnwell in 1936 and then became Chief Engineer after Barnwell’s death. Another significant graduate from the pre-department years was Archibald Russell. He was appointed Chief Designer of Bristol Aeroplane Company in 1946, becoming a leading structures expert and, eventually, Managing Director and then Chairman at British Aircraft Corporation Filton. In June 1945, at the end of the second world war, the Bristol Aeroplane Company offered to fund a Chair in Aeronautical Engineering at the University [2]. Sir Alfred Pugsley, who had been the distinguished Head of Structural Engineering at the Royal Aircraft Establishment (RAE) Farnborough had just taken up the chair of Civil Engineering at Bristol. He persuaded Roderick Collar, a mathematician and engineer with whom he had worked closely with at the RAE during the war, to apply and he was appointed as the first holder of the Sir George White Chair [2]. The first six undergraduates arrived in October 1946 and graduated in 1948.","PeriodicalId":22567,"journal":{"name":"The Aeronautical Journal (1968)","volume":"3 1","pages":"163 - 166"},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76091753","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The Royal Aeronautical Society Written Paper Prizes are awarded annually for the best papers published in The Aeronautical Journal by the Society during the previous calendar year. Awards can be conferred at Gold, Silver or Bronze level. A new prize for the best paper to appear in the Journal of Aeronautical History has recently been added. The Written Paper Prizes are presented following the approval of the Council of the Royal Aeronautical Society on the basis of recommendations from the RAeS Medals & Awards Committee, supported by the Editor-in-Chief of The Aeronautical Journal. The Society recognises the achievements, innovation and excellence of both individual and multiple authors.
{"title":"The RAeS 2021 Written Paper Prizes","authors":"","doi":"10.1017/aer.2022.107","DOIUrl":"https://doi.org/10.1017/aer.2022.107","url":null,"abstract":"The Royal Aeronautical Society Written Paper Prizes are awarded annually for the best papers published in The Aeronautical Journal by the Society during the previous calendar year. Awards can be conferred at Gold, Silver or Bronze level. A new prize for the best paper to appear in the Journal of Aeronautical History has recently been added. The Written Paper Prizes are presented following the approval of the Council of the Royal Aeronautical Society on the basis of recommendations from the RAeS Medals & Awards Committee, supported by the Editor-in-Chief of The Aeronautical Journal. The Society recognises the achievements, innovation and excellence of both individual and multiple authors.","PeriodicalId":22567,"journal":{"name":"The Aeronautical Journal (1968)","volume":"1 1","pages":"1 - 1"},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91528401","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The objective of this paper is to present the movement mechanisms of transport aircraft response to severe clear-air turbulence to obtain the loss of control prevention for pilot training in IATA – Loss of Control In-flight (LOC-I) program. The transport aircraft in transonic flight is subjected to severe clear-air turbulence, resulting in a sudden plunging motion with the abrupt change in flight attitude and gravitational acceleration. The comparative analyses of the flight environment and aircraft response to severe clear-air turbulence for two four-jet aircraft are studied. The one with a larger dropped-off altitude during the plunging motion will be chosen to construct the movement mechanism. The nonlinear unsteady aerodynamic model of the chosen transport is established through flight data mining and the fuzzy-logic modeling of artificial intelligence technique based on post-flight data. The crosswind before the turbulence encounter will easily induce a rolling motion and then the sudden plunging motion during the turbulence encounter. The influences of the varying vertical wind and crosswind on loss of control are presented. To formulate preventive actions, the situation awareness of varying crosswind encountering for the operational pilot will be studied further in the future. The present study is initiated to examine the possible mitigation concepts of accident prevention for the pilot training course of IATA – Loss of Control In-flight (LOC-I) program.
{"title":"Movement mechanisms for transport aircraft during severe clear-air turbulence encounter","authors":"W. Jiang, R. C. Chang, N. Yang, M. Ding","doi":"10.1017/aer.2022.77","DOIUrl":"https://doi.org/10.1017/aer.2022.77","url":null,"abstract":"\u0000 The objective of this paper is to present the movement mechanisms of transport aircraft response to severe clear-air turbulence to obtain the loss of control prevention for pilot training in IATA – Loss of Control In-flight (LOC-I) program. The transport aircraft in transonic flight is subjected to severe clear-air turbulence, resulting in a sudden plunging motion with the abrupt change in flight attitude and gravitational acceleration. The comparative analyses of the flight environment and aircraft response to severe clear-air turbulence for two four-jet aircraft are studied. The one with a larger dropped-off altitude during the plunging motion will be chosen to construct the movement mechanism. The nonlinear unsteady aerodynamic model of the chosen transport is established through flight data mining and the fuzzy-logic modeling of artificial intelligence technique based on post-flight data. The crosswind before the turbulence encounter will easily induce a rolling motion and then the sudden plunging motion during the turbulence encounter. The influences of the varying vertical wind and crosswind on loss of control are presented. To formulate preventive actions, the situation awareness of varying crosswind encountering for the operational pilot will be studied further in the future. The present study is initiated to examine the possible mitigation concepts of accident prevention for the pilot training course of IATA – Loss of Control In-flight (LOC-I) program.","PeriodicalId":22567,"journal":{"name":"The Aeronautical Journal (1968)","volume":"12 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91162550","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Abstract The pulsed jet is a novel and effective active mixing enhancement approach. For the transverse pulsed jet in the supersonic crossflow, the frequency influence is investigated using the three-dimensional Reynolds-averaged Navier–Stokes (RANS) equations coupled with the SST k-ω turbulence model. The averaged flow field properties of the pulsed jet are better than those of the steady jet when considering mixing efficiency and jet penetration depth, especially for the case with the pulsed frequency being 50kHz. The flow field structures of the pulsed jet are connected with the time, with periodic wave structures generating in the flow field and moving downstream. The size of the wave structures and its distance are related to the frequency, namely the size and flow distance are relatively small at 50kHz, and it takes some time for the pulsed jet to establish its influence in the full flow field. At low frequencies, the flow field produces large fluctuations, and this may be detrimental to the stable operation of the engine.
{"title":"Investigation on frequency influence on the transverse pulsed jet in a supersonic crossflow","authors":"Z.-Z. Xu, Ym Zhou, J.-P. Wu, W. Huang","doi":"10.1017/aer.2022.98","DOIUrl":"https://doi.org/10.1017/aer.2022.98","url":null,"abstract":"Abstract The pulsed jet is a novel and effective active mixing enhancement approach. For the transverse pulsed jet in the supersonic crossflow, the frequency influence is investigated using the three-dimensional Reynolds-averaged Navier–Stokes (RANS) equations coupled with the SST k-ω turbulence model. The averaged flow field properties of the pulsed jet are better than those of the steady jet when considering mixing efficiency and jet penetration depth, especially for the case with the pulsed frequency being 50kHz. The flow field structures of the pulsed jet are connected with the time, with periodic wave structures generating in the flow field and moving downstream. The size of the wave structures and its distance are related to the frequency, namely the size and flow distance are relatively small at 50kHz, and it takes some time for the pulsed jet to establish its influence in the full flow field. At low frequencies, the flow field produces large fluctuations, and this may be detrimental to the stable operation of the engine.","PeriodicalId":22567,"journal":{"name":"The Aeronautical Journal (1968)","volume":"32 1","pages":"1255 - 1268"},"PeriodicalIF":0.0,"publicationDate":"2022-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80063768","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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