Artículos de revistas: "Flight mechanic"

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Manzanera, R. A. Jiménez y H. Smith. "Flight in nature I: Take-off in animal flyers". Aeronautical Journal 119, n.º 1213 (marzo de 2015): 257–80. http://dx.doi.org/10.1017/s0001924000010472.

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AbstractIn this review paper, several take-off techniques of different species of animal flyers and gliders, both extinct and extant, are analysed. The methods they use vary according to animal group and size. Smaller animals, such as insects, rely on the use of transient aerodynamic techniques or the use of stored elastic energy. Medium-size flyers such as birds, bats, and other mammal gliders initiate flight by a jump which involves leg and wing movement coordination. The largest animals to fly, the extinct pterosaurs, are believed to have used a combination of aerodynamic and mechanic techniques in order to become airborne. The information presented here can be used as a resource for novel biomimetic unmanned aircraft design.

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Köthe, Alexander y Robert Luckner. "Applying Eigenstructure Assignment to Inner-Loop Flight Control Laws for a Multibody Aircraft". CEAS Aeronautical Journal 13, n.º 1 (21 de diciembre de 2021): 33–43. http://dx.doi.org/10.1007/s13272-021-00549-z.

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AbstractUnmanned aircraft used as high-altitude platform system has been studied in research and industry as alternative technologies to satellites. Regarding actual operation and flight performance of such systems, multibody aircraft seems to be a promising aircraft configuration. In terms of flight dynamics, this aircraft strongly differs from classical rigid-body and flexible aircraft, because a strong interference between flight mechanic and formation modes occurs. For unmanned operation in the stratosphere, flight control laws are required. While control theory generally provides a number of approaches, the specific flight physics characteristics can be only partially considered. This paper addresses a flight control law approach based on a physically exact target model of the multibody aircraft dynamics rather than conventionally considering the system dynamics only. In the target model, hypothetical spring and damping elements at the joints are included into the equations of motion to transfer the configuration of a highly flexible multibody aircraft into one similar to a classical rigid-body aircraft. The differences between both types of aircraft are reflected in the eigenvalues and eigenvectors. Using the eigenstructure assignment, the desired damping and stiffness are established by the inner-loop flight control law. In contrast to other methods, this procedure allows a straightforward control law design for a multibody aircraft based on a physical reference model.

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3

Lin, Yide. "The Development and Challenges of More Electric Aircraft". Highlights in Science, Engineering and Technology 27 (27 de diciembre de 2022): 814–19. http://dx.doi.org/10.54097/hset.v27i.3850.

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The development of electrical and electronic engineering makes the replacement of conventional hydraulic, mechanic, and pneumatic system into electrical system become much more possible. That means the secondary power of aircraft will be dominated by electricity, rather than hydraulic oil or bleed air from the engine. The Boeing 787 and Airbus A380 has applied these technologies significantly and their fuel consumption and noise level during flight are also get improved by comparison with their counterpart which has traditional hydraulic and pneumatic system. On the other side, the mass application of electrical driven components on board will lead to various new challenges to aircraft design when concerning the weight and flight safety due to the characteristics of those components. In this paper, technologies implemented, and challenges will be introduced through reviewing literatures. The benefit and drawbacks will be concluded by comparing electrical and hydraulic and pneumatic system.

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Li, He, Gang Zou, Lin Li y Dehui Yu. "Helicopter Training Simulator Measurement and Control System Based on Computer Simulation Technology". Journal of Physics: Conference Series 2143, n.º 1 (1 de diciembre de 2021): 012011. http://dx.doi.org/10.1088/1742-6596/2143/1/012011.

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Abstract With the development of computer software technology and simulation technology, simulation training has been widely used. Helicopter training simulation has become an important part of helicopter training, and its status is becoming more and more important. On the one hand, the air mechanic is responsible for the maintenance and organization of the helicopter during the flight, and on the other hand is responsible for the starting and stopping of the helicopter engine, the operation of related equipment, and the handling of emergencies during the flight. The simulation training has the characteristics of high training efficiency, convenient maintenance and low training cost. It will become an important means for helicopter air mechanics to troubleshoot and deal with special situations. This paper aims to study the helicopter training simulator measurement and control system based on computer software technology. Based on the analysis of the advantages of the simulator instead of the actual installation for training, the helicopter training simulator function and the simulator subsystem, the actual installation simulation instrument and signal are designed. The indicator light, the graphic instrument and the control signal are arranged in the circuit, and then the simulation experiment is carried out on the design. The experimental results show that the design can more accurately simulate the indication of the antenna elevation angle table, which meets the requirements of this article.

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Ristantya, Alfandira Rossa, Bina Kurniawan y Ida Wahyuni. "HUBUNGAN ANTARA KARAKTERISTIK PEKERJA DAN PENGAWASAN TERHADAP PERILAKU TIDAK AMAN PADA TEKNISI PERAWATAN HANGAR PESAWAT PT X". Jurnal Kesehatan Masyarakat (Undip) 10, n.º 3 (5 de mayo de 2022): 267–72. http://dx.doi.org/10.14710/jkm.v10i3.30875.

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Unsafe behavior is a failure to apply work rules and procedures, resulting in work accidents. Work accidents in the aviation are not spared from work accidents that can be experienced by technicians when carrying out aircraft maintenance and repairs. The development of the aviation industry in Indonesia is not proportional to the availability of the number of flight technician workers, resulting in an increase of work-related accidents experienced by flight technicians. Therefore, an approach is needed to determine the behavior of technicians that cause work accidents. This study aims to analyze the relationship between worker characteristics (knowledge, attitude, and working period) and supervision with unsafe behavior in PT X hangar maintenance technicians. This research is quantitative research with cross-sectional study design. The sample in this study were mechanic technicians shift I totaling 120 people who were obtained by random sampling. Data in this study were collected by using a questionnaire and the results were tested using the chi square test. The results of this study indicate that there is a correlation between attitude (p-value: 0,000) on unsafe behavior in PT X aircraft maintenance technicians. Meanwhile, there was no correlation between knowledge (p-value: 0.388), work period (p-value: 0.694), supervision (p-value: 0.305) and unsafe behavior. From the results obtained, hopefully management can add topics to safety briefings and improve the safety information media.

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Bai, Bo, Ziyang Zhao, Kai Yuan, Rongxin Tang, Xiaohua Deng, Mingyang Mao, Jiawei Xiong y Kaili Wang. "Characteristics of EHF Wave Propagation in Hypersonic Plasma Sheaths Magnetized by Dipole Magnetic Fields". Applied Sciences 12, n.º 6 (18 de marzo de 2022): 3105. http://dx.doi.org/10.3390/app12063105.

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Communication blackout is always a serious threat to the flight tasks of modern hypersonic vehicles moving in near space. EHF communication is considered as a potential solution to the blackout problem. Nevertheless, EHF waves suffer from severe attenuation in hypersonic plasma sheaths. An external magnetic field could mitigate EHF wave attenuation in hypersonic plasma sheaths. Dipole magnetic fields, generated by coils, are feasible in realistic scenarios. In the present study, a model for EHF wave propagation in hypersonic plasma sheaths magnetized by dipole magnetic fields that are generated with coils is developed. The dissipation caused by the inhomogeneity of dipole magnetic fields and the magnetic field component of electromagnetic waves are compared with the dissipation yielded by the collision between electrons and neutral particles. The results show that collision is still the main dissipation mechanic for EHF waves. The study also found that, in the blunt-coned plasma sheath, the mitigation effect of a dipole magnetic field is weaker than that of a uniform magnetic field. The mechanics which yield the difference is analyzed. In addition, the relation between the characteristics of EHF waves and the coil parameters is investigated. Suggestions for the coil parameters and the operation frequencies of the EHF communication systems are made based on the investigation.

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7

Gao, Xinglong, Qingbin Zhang y Qiangang Tang. "Fluid-Structure Interaction Analysis of Parachute Finite Mass Inflation". International Journal of Aerospace Engineering 2016 (2016): 1–8. http://dx.doi.org/10.1155/2016/1438727.

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Parachute inflation is coupled with sophisticated fluid-structure interaction (FSI) and flight mechanic behaviors in a finite mass situation. During opening, the canopy often experiences the largest deformation and loading. To predict the opening phase of a parachute, a computational FSI model for the inflation of a parachute, with slots on its canopy fabric, is developed using the arbitrary Lagrangian-Euler coupling penalty method. In a finite mass situation, the fluid around the parachute typically has an unsteady flow; therefore, a more complex opening phase and FSI dynamics of a parachute are investigated. Navier-Stokes (N-S) equations for uncompressible flow are solved using an explicit central difference method. The three-dimensional visualization of canopy deformation as well as the evolution of dropping velocity and overload is obtained and compared with the experimental results. This technique could be further applied in the airdrop test of a parachute for true prediction of the inflation characteristics.

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8

Calvert, B. J. "Aircrew and Automation". Journal of Navigation 38, n.º 1 (1 de enero de 1985): 1–18. http://dx.doi.org/10.1017/s0373463300038121.

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On 18 June, 1914 Lawrence, son of Elmer Sperry (founder of the Sperry Gyroscope Company) flew over a crowd assembled at Argenteuil, near Paris (Fig. 1). His aircraft was a Curtiss C2 flying boat and the purpose of the flight was to demonstrate the Sperry Gyroscopic Stabilizer in a competition organized by the Aero Club of France. It was a dramatic demonstration. On the first pass over the crowd Lawrence Sperry stood up and held both hands in the air whilst his mechanic, Emile Cachin, walked out on the wing and stood holding one of the struts. The lateral stability of the aeroplane was undisturbed, but the spectators were able to see the ailerons move to compensate for the engineer's weight. This performance was repeated several times and Sperry also demonstrated the automatic ‘volplaning’ function of the system which caused the aircraft to dive and regain speed in the event of an approach to the stall. The company was awarded a prize of 50000 francs as winner of the competition.

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9

Cipolla, Vittorio, Davide Zanetti, Karim Abu Salem, Vincenzo Binante y Giuseppe Palaia. "A Parametric Approach for Conceptual Integration and Performance Studies of Liquid Hydrogen Short–Medium Range Aircraft". Applied Sciences 12, n.º 14 (6 de julio de 2022): 6857. http://dx.doi.org/10.3390/app12146857.

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The present paper deals with the investigation, at conceptual level, of the performance of short–medium-range aircraft with hydrogen propulsion. The attention is focused on the relationship between figures of merit related to transport capability, such as passenger capacity and flight range, and the parameters which drive the design of liquid hydrogen tanks and their integration with a given aircraft geometry. The reference aircraft chosen for such purpose is a box-wing short–medium-range airplane, the object of study within a previous European research project called PARSIFAL, capable of cutting the fuel consumption per passenger-kilometre up to 22%. By adopting a retrofitting approach, non-integral pressure vessels are sized to fit into the fuselage of the reference aircraft, under the assumption that the main aerodynamic, flight mechanic, and structural characteristics are not affected. A parametric model is introduced to generate a wide variety of fuselage-tank cross-section layouts, from a single tank with the maximum diameter compatible with a catwalk corridor to multiple tanks located in the cargo deck, and an assessment workflow is implemented to perform the structural sizing of the tanks and analyse their thermodynamic behaviour during the mission. This latter is simulated with a time-marching approach that couples the fuel request from engines with the thermodynamics of the hydrogen in the tanks, which is constantly subject to evaporation and, depending on the internal pressure, vented-out in gas form. Each model is presented in detail in the paper and results are provided through sensitivity analyses to both the technologic parameters of the tanks and the geometric parameters influencing their integration. The guidelines resulting from the analyses indicate that light materials, such as the aluminium alloy AA2219 for tanks’ structures and polystyrene foam for the insulation, should be selected. Preferred values are also indicted for the aspect ratios of the vessel components, i.e., central tube and endcaps, as well as suggestions for the integration layout to be adopted depending on the desired trade-off between passenger capacity, as for the case of multiple tanks in the cargo deck, and achievable flight ranges, as for the single tank in the section.

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10

Grigore, Jan Cristian. "Aspects Concerning the Dynamics of the Mechanisms with Clearances". Advanced Materials Research 837 (noviembre de 2013): 411–15. http://dx.doi.org/10.4028/www.scientific.net/amr.837.411.

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The clearances in the cinematic links appear due to the long functioning. In the paper we shall make a few considerations of geometric and mechanic type about the clearances in the linkages, linkages planes with rotation joint links. We shall elaborate methods to study the influence of the clearances. Consider a rotational kinematic coupling clearance, the clearance being defined by the distance, difference between the radius of the bearing and the radius of the journal. This relationship between elements is unilateral. Journal's behaviour inside the bearing can be highlighted the value normal reaction force. The journal can have the following phases, phase contact (when there is contact between the bearing and journal, the normal reaction force is zero) flight phase (no contact between end journal bearing at this stage is normal reaction force 0). It is considered the most dangerous phase, recovery phase of flight phase where the contact is restored. In this phase occurs shocks, shocks in turn produce vibration in the mechanism leading to the destruction of the system. The clearance size is directly proportional to magnitude impact and vibration level especially high. To be reduced or even eliminated these shocks, the paper presents a solution. Crank Mechanism with clearance, mechanism considered in this paper applies a force so that maintain contact between the bearing and journal, is considered the center of gravity of the connecting rod the forces and the moment. Based on the relations obtained from equation echililibru and vector equation of the contour goes to the numerical calculation for the engine element is inserted angle value (which defines the initial position of the mechanism), one deduces the angles, which define the position of the mechanism. Any would be their source of appearance, they usually produce unwished effects during the mechanisms functioning.

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Rusdiana, Agus. "Analisis Kinematika Gerakan Track Start dalam Olahraga Renang". JUARA : Jurnal Olahraga 5, n.º 2 (11 de junio de 2020): 143–50. http://dx.doi.org/10.33222/juara.v5i2.881.

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Sekarang ini teknik start dalam olahraga renang yang banyak digunakan adalah track start baik teknik rear weighted maupun front weighted serta grab start. Perbedaan utama antara kedua teknik start adalah posisi kaki pada papan start block. Tujuan dari penelitian ini adalah menganalisis perbedaan kinematika gerak dengan pendekatan analisis tiga dimensi antara atlet putra dan putri dengan menggunakan teknik track start dalam olahraga renang. Metoda yang digunakan dalam penelitian ini adalah deskriptif kuantitatif. Sampel yang digunakan adalah atlet putra 8 orang dan putri 8 dengan rata-rata usianya 19.5 tahun, tinggi badan 1.72 m dan berat badan 61.4 kg. Proses pengabilan data menggunakan satu buah 3D Force Platform, 3 buah Panasonic Handycam, Frame DIAZ IV 3D motion software dan satu set marker manual. Hasil dari analisis data menujukan bahwa dari 21 parameter kinematika gerak yang dianalisis terdapat perbedaan yang signifikan pada kelompok putra yang hasilnya lebih besar daripada kelompok putri khususnya pada 7 parameter yaitu pada flight time, total time, height of take-off, vertical velocity of the CoM at take-off, leg power, force dan time to 15m. Sedangkan peran sumbangan mechanic leg power dan force sesaat sebelum take off merupakan faktor kunci keberhasilan performa start dalam olahraga renang.

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Tùng, Lưu Thanh. "Study on the radial clearance of the screw conveyor for transporting cement". Science & Technology Development Journal - Engineering and Technology 2, n.º 3 (22 de enero de 2020): 153–62. http://dx.doi.org/10.32508/stdjet.v2i3.577.

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Nowadays, screw conveyors have been used to transport bulk materials since historical times. They are composed of a helical flight (screw), a driving shaft connected to a driving device, a casing U-trough or pipe, and so on. The principle of conveying materials relies on the friction between materials and the rotating screw or the casing. The advantages of screw conveyors are compact design, low maintenance, and the ability to transport materials continuously and safely. Screw conveyors have been used not only as bulk handling equipment to transport materials but also as parts of construction and mining machinery, e.g., underground tunneling machines, in which they are used to discharge soil or rock continuously. As volumetric devices, screw conveyor generally provide relatively precise throughput control while meeting other requirements, e.g. environmental protection. A screw feeder typically consists of a storage container (bin or hopper) coupled to a screw casing and a screw within. They are suitable for conveying dry material or grain. Although mechanical structure of screw conveyor seems very simple, mechanic of transport action is very complicated. The periodic boundary, inclination, speed of rotation, radial clearance etc. influence productivity, mass flow rate. Following theoretical studies, the radial clearance should be very small, however, in reality, the bulk material cannot go through the clearance, that makes the screw stuck and then stop. However, when the radial clearance is larger, productivity decreases very fast. In this paper, the cement is transported by screw conveyor. The experiment is done with different parameters such as speed of rotation and the radial clearance. The productivity is recorded with each change of parameters. The result from the experiment will predict the best radial clearance to transport the cement. The paper will conclude the area having high productivity and low productivity.

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DeLaurier, J. D. y J. M. Harris. "A study of mechanical flapping-wing flight". Aeronautical Journal 97, n.º 968 (octubre de 1993): 277–86. http://dx.doi.org/10.1017/s0001924000026452.

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Abstract The feasibility of mechanical flapping-wing flight has been studied by analyses and experiments. The key results from this work include the development of an efficient wing with unique features for twisting and lift balance, as well as a lightweight and reliable drive mechanism. These were incorporated into a radio-controlled, engine-powered, flapping-wing aeroplane (ornithopter), whose flight tests have been the proof-of-concept focus of this research. In September 1991, this aircraft achieved successful sustained flights, demonstrating the practicability of this particular solution for mechanical flapping-wing flight.

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Jakielaszek, Zbigniew y Mirosław Nowakowski. "Studying the strength of an S2-3a flight data recording system flight recorder". Mechanik, n.º 4 (abril de 2020): 6–12. http://dx.doi.org/10.17814/mechanik.2020.4.9.

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Zhang, Hong-Hai, Qing-Wen Xue y Yu Jiang. "Multi-objective gate assignment based on robustness in hub airports". Advances in Mechanical Engineering 9, n.º 2 (febrero de 2017): 168781401668858. http://dx.doi.org/10.1177/1687814016688588.

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To enhance the robustness of the gate assignment, reduce the possibility of flight conflict, and improve the quality of passenger services, a multi-objective gate assignment model is proposed by minimizing flight conflict probability and number of flights assigned to aprons. The biogeography-based optimization algorithm is used to solve the proposed model with a new method for estimating the conflict probability. The simulation results show that the ratio of interval time of two flights assigned to the same gate between 60 and 120 min is as high as 82% when the rate of the flights assigned to aprons is controlled below 0.4. This means that the robustness increases greatly, and the probability of flight conflicts decreases, which is beneficial to the implement of flight assignment plan. In addition, the biogeography-based optimization algorithm is more effective to solve the proposed model and very easy to find out the optimal solutions.

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Sanguinetti, Angela y Nina Amenta. "Nudging Consumers Toward Greener Air Travel by Adding Carbon to the Equation in Online Flight Search". Transportation Research Record: Journal of the Transportation Research Board 2676, n.º 2 (18 de octubre de 2021): 788–99. http://dx.doi.org/10.1177/03611981211046924.

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This study explores the potential to promote lower-emissions air travel by providing consumers with information about the carbon emissions of alternative flight choices in the context of online flight search and booking. We surveyed over 450 employees of the University of California, Davis, asking them to choose among hypothetical flight options for university-related business trips. Emissions estimates for flight alternatives were prominently displayed alongside cost, layovers, and airport, and the lowest-emissions flight was labeled “Greenest Flight.” We found an impressive rate of willingness to pay for lower-emissions flights: around $200/ton of CO2e saved, a magnitude higher than that seen in carbon offsets programs, and consistent with findings from a prior study with a non-university-based sample. In a second step of analysis, we estimated the carbon and cost impacts if the university were to adopt a flight-search interface that prioritizes carbon emissions information and displays alternatives from multiple regional airports in their employee travel-booking portal. We estimated potential annual savings of 79 tons of CO2e, while reducing airfare costs by $56,000, mainly through an increased willingness of travelers to take advantage of cheaper nonstop (lower-emissions) flights from a more distant airport in the region over indirect flights from their preferred airport for medium-distance flights. Institutionalizing this strategy within organizations with large travel budgets could reduce personal and organizational carbon footprints. If implemented across major flight-search engines, it could potentially reduce the demand for higher-emissions flights, leading to an industry-wide impact on aviation emissions.

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Nudds, R. L. y D. M. Bryant. "The energetic cost of short flights in birds". Journal of Experimental Biology 203, n.º 10 (15 de mayo de 2000): 1561–72. http://dx.doi.org/10.1242/jeb.203.10.1561.

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Many small birds perform short flights, for which take-offs, ascents and descents form a large component of the total flight time and which are characterised by low airspeeds. Using the doubly-labelled water technique, zebra finches Taeniopygia guttata engaging in repeated short flights were found to expend 13.65 kJ more than ‘non-flying’ controls, which equated to a flight expenditure of 27.8 times their basal metabolic rate. This is over three times the predicted flight expenditure derived from existing aerodynamic models. These data were used to determine a coefficient (0.11) for converting the mechanical power derived from aerodynamic models into metabolic power. An equation is presented, based on body mass, which can be used to predict the costs of short flights in ecological and behavioural studies of birds.

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Lee, Seung Yong, Paul Bates, Patrick Murray y Wayne Martin. "Training Flight Accidents". Aviation Psychology and Applied Human Factors 7, n.º 2 (septiembre de 2017): 107–13. http://dx.doi.org/10.1027/2192-0923/a000121.

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Abstract. Civil aviation is broadly categorized into two sectors: air transportation and general aviation. While the former sector is considered to be ultrasafe the latter requires a stronger focus on safety improvement. There has been considerable research examining the causes of general aviation accidents with a view to improving safety. However, there has been very limited research specifically focused on accidents involving training flights and associated causal factors. A total of 293 training flight accident reports, comprising 111 fatal and 182 nonfatal accidents were reviewed and analyzed to identify causes of training-flight accidents. The study found that based on the odds ratio, if a fatal accident involving training flights occurred it was 4.05 times more likely to be a dual training flight. Other findings included that most accidents occurred during the landing phase and the majority of accidents related to skill deficiency (e.g., an improper/inadequate flare). This was a major causal factor in nonfatal accidents in both dual and solo training flights. However, on dual training flights there were more fatal accidents involving decision deficiencies and mechanical malfunctions (e.g., loss of engine power). A previous study suggested that lack of supervision of student pilots by flight instructors was found to be a main causal factor and thus flight instructor training and recurrency requirements need to be reviewed.

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Chai, P. y R. Dudley. "Limits to flight energetics of hummingbirds hovering in hypodense and hypoxic gas mixtures." Journal of Experimental Biology 199, n.º 10 (1 de octubre de 1996): 2285–95. http://dx.doi.org/10.1242/jeb.199.10.2285.

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Hovering hummingbirds offer a model locomotor system for which analyses of both metabolism and flight mechanics are experimentally tractable. Because hummingbirds exhibit the highest mass-specific metabolic rates among vertebrates, maximum performance of hovering flight represents the upper limit of aerobic locomotion in vertebrates. This study evaluates the potential constraints of flight mechanics and oxygen availability on maximum flight performance. Hummingbird flight performance was manipulated non-invasively using air and gas mixtures which influenced metabolism via variable oxygen partial pressure and/or altered flight mechanics via variable air densities. Limits to the locomotor capacity of hovering ruby-throated hummingbirds (Archilochus colubris) were unequivocally indicated by aerodynamic failure in either air/helium or air/heliox mixtures. Air/helium mixtures are hypodense and hypoxic; failure to sustain hovering flight occurred at 63% of the density of sea-level air and at an oxygen concentration of 12%. Air/heliox mixtures are hypodense but normoxic; failure in hovering occurred at 47% of sea-level air density. Thus, hummingbirds demonstrated considerable power reserves in hovering flight as well as hypoxic tolerance. In air/helium mixtures, hovering was limited by oxygen supply and not by flight mechanics. Birds hovering in air/helium mixtures increased their mechanical power output but not their rate of oxygen consumption. By contrast, birds hovering in air/heliox mixtures increased both mechanical performance and metabolic expenditure. Under hypoxia, hovering hummingbirds demonstrated non-negligible, but still limited, capacities for anaerobic metabolism and/or oxygen storage. Depending on the physical context, hummingbird flight performance can therefore be limited by oxygen availability or by flight aerodynamics.

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Vigoreaux, J. O., C. Hernandez, J. Moore, G. Ayer y D. Maughan. "A genetic deficiency that spans the flightin gene of Drosophila melanogaster affects the ultrastructure and function of the flight muscles." Journal of Experimental Biology 201, n.º 13 (1 de julio de 1998): 2033–44. http://dx.doi.org/10.1242/jeb.201.13.2033.

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We have developed a reverse-genetic approach to study the function of flightin, a unique protein of the flight muscle myofibril of Drosophila melanogaster. We describe the generation and characterization of Df(3L)fln1, a lethal genetic deficiency in the 76BE region of the third chromosome which deletes several genes, including the gene for flightin. We show that heterozygous flies harboring the Df(3L)fln1 mutation exhibit both impaired flight and ultrastructural defects in their flight muscle myofibrils. We found that the mutation does not interfere with assembly of the myofibril but leads to disorganization of peripheral myofilaments in adult myofibrils. Most myofibrils, nevertheless, retain an intact core that represents approximately 80 % of the normal lattice diameter. Mechanical analysis of single skinned flight muscle fibers demonstrates that the mutation has no significant effect on net power output but increases the frequency at which maximum power is delivered to the wings, potentially reducing the overall performance of the flight system. The results suggest that flightin is an indispensable part of the flight muscle contractile mechanism.

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Warchulski, Marcin y Jacek Warchulski. "Flight simulation software design of long range ballistic missiles". Mechanik, n.º 7 (julio de 2015): 569/943–569/950. http://dx.doi.org/10.17814/mechanik.2015.7.315.

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Zygmunt, Bogdan y Krzysztof Motyl. "Flight computer animation of a rocket missile in Mathcad". Mechanik, n.º 7 (julio de 2015): 570/997–570/1006. http://dx.doi.org/10.17814/mechanik.2015.7.321.

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Liu, Hao, Toshiyuki Nakata, Na Gao, Masateru Maeda, Hikaru Aono y Wei Shyy. "Micro air vehicle-motivated computational biomechanics in bio-flights: aerodynamics, flight dynamics and maneuvering stability". Acta Mechanica Sinica 26, n.º 6 (diciembre de 2010): 863–79. http://dx.doi.org/10.1007/s10409-010-0389-5.

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24

Bużantowicz, Witold. "Modeling of ballistic missile flight trajectory in a central gravitational field". Mechanik, n.º 7 (julio de 2015): 557/73–557/82. http://dx.doi.org/10.17814/mechanik.2015.7.216.

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Zhang, Rui, Peng Xie, Chaoying Zhou y Chao Wang. "Three-dimensional numerical study on the interaction of contralateral insect wings in asymmetric stroke". Proceedings of the Institution of Mechanical Engineers, Part G: Journal of Aerospace Engineering 232, n.º 9 (23 de marzo de 2017): 1671–84. http://dx.doi.org/10.1177/0954410017699004.

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Asymmetric flight of insects and birds is often seen in nature which is a conventional way for them to obtain the flexibility of maneuver in turning, hovering, and gliding. A numerical study on the interaction between contralateral wings of a dragonfly in asymmetric forward flight is carried out using the finite volume method. Various asymmetric flights with different advance ratios are considered where the aerodynamic forces, torques of each wing, pressure distributions, vorticity, and velocity fields are analyzed. A number of symmetric flights corresponding to the asymmetric flights are also studied. The results indicate that the interaction between the contralateral wings of a dragonfly is very small even when the dragonfly is in an asymmetric flight no matter how the advance ratios vary in the range concerned. With a typical example of asymmetric forward flights the difference in the mean value of vertical force coefficient is generally less than 5% compared with that for its corresponding symmetric flight. It is found that a small lateral flow region (LFR) is formed near the body, and there is a small lateral flow across the symmetric plane of the body. But this flow is very weak and resulted interaction between contralateral wings is very small. The result has confirmed in a way that dragonflies take a quite different way from fruit flies to obtain the lift with the contralateral wings. That is, fruit flies employ clap-and-fling mechanism which needs contralateral wings to be close enough to extrude the flow and generate lift, which means the contralateral two wings are so close that strong interaction happens, while dragonflies flap their contralateral wings on two sides of the vertical central plane with a relatively far distance between the wings where the interaction of contralateral wings is negligibly weak.

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26

Wakeling, JM y CP Ellington. "Dragonfly flight. III. Lift and power requirements." Journal of Experimental Biology 200, n.º 3 (1 de febrero de 1997): 583–600. http://dx.doi.org/10.1242/jeb.200.3.583.

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A mean lift coefficient quasi-steady analysis has been applied to the free flight of the dragonfly Sympetrum sanguineum and the damselfly Calopteryx splendens. The analysis accommodated the yaw and accelerations involved in free flight. For any given velocity or resultant aerodynamic force (thrust), the damselfly mean lift coefficient was higher than that for the dragonfly because of its clap and fling. For both species, the maximum mean lift coefficient L was higher than the steady CL,max. Both species aligned their strokes planes to be nearly normal to the thrust, a strategy that reduces the L required for flight and which is different from the previously published hovering and slow dragonfly flights with stroke planes steeply inclined to the horizontal. Owing to the relatively low costs of accelerating the wing, the aerodynamic power required for flight represents the mechanical power output from the muscles. The maximum muscle mass-specific power was estimated at 156 and 166 W kg-1 for S. sanguineum and C. splendens, respectively. Measurements of heat production immediately after flight resulted in mechanical efficiency estimates of 13 % and 9 % for S. sanguineum and C. splendens muscles, respectively.

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27

PENNYCUICK, C. J., M. R. FULLER y LYNNE McALLISTER. "Climbing Performance of Harris' Hawks (Parabuteo Unicinctus) with Added Load: Implications for Muscle Mechanics and for Radiotracking". Journal of Experimental Biology 142, n.º 1 (1 de marzo de 1989): 17–29. http://dx.doi.org/10.1242/jeb.142.1.17.

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Two Harris' hawks were trained to fly along horizontal and climbing flight paths, while carrying loads of various masses, to provide data for estimating available muscle power during short flights. The body mass of both hawks was about 920 g, and they were able to carry loads up to 630 g in horizontal flight. The rate of climb decreased with increasing all-up mass, as also did the climbing power (product of weight and rate of climb). Various assumptions about the aerodynamic power in low-speed climbs led to estimates of the maximum power output of the flight muscles ranging from 41 to 46 W. This, in turn, would imply a stress during shortening of around 210 kPa. The effects of a radio package on a bird that is raising young should be considered in relation to the food load that the forager can normally carry, rather than in relation to its body mass.

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28

Verhagen, Collin MA, Hendrikus G. Visser y Bruno F. Santos. "A decentralized approach to formation flight routing of long-haul commercial flights". Proceedings of the Institution of Mechanical Engineers, Part G: Journal of Aerospace Engineering 233, n.º 8 (3 de agosto de 2018): 2992–3004. http://dx.doi.org/10.1177/0954410018791068.

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This paper describes the development of an optimization-based cooperative planning system for the efficient routing and scheduling of extended flight formations. This study considers the use of formation flight as a means to reduce the overall fuel consumption in long-haul airline operations. It elaborates on the operational implementation of formation flight, particularly focusing on the formation flight routing. A completely decentralized approach is presented, in the sense that formation flight is not planned pre-flight and is not subjected to any predefined routing restrictions. A greedy communication scheme is defined through which all participating aircraft are allowed to communicate with neighboring aircraft in order to establish flight formations in flight. A constraint on the formation-flight-induced additional flight time is introduced in order to suppress the occurrence of large detours in the assembly of flight formations. A transatlantic case study is presented that considers 347 eastbound flights. Assuming a 10% fuel flow reduction for any trailing aircraft in a formation, the overall network-wide fuel savings were estimated at 4.3% at the expense of an additional flight time of 10.3 min per flight on average. In this transatlantic long-haul scenario, a formation flight usage rate of 73% was realized.

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29

Zhu, Lin, Chun Yan Zhu, Hong Bin Gu y Guang Qiang Wang. "Visualized Flight Control and Flight Mechanics Calculation". Advanced Materials Research 562-564 (agosto de 2012): 759–62. http://dx.doi.org/10.4028/www.scientific.net/amr.562-564.759.

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Aircraft basic performance is the foundation of the research on aircraft, which is characterized by many parameters. According to the example of the shortest rising time spent on flying from an altitude to another arbitrary one, and the example of matching control of joystick and throttle lever, it is demonstrated that the visualization in scientific computing method is useful for promoting engineering research.

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30

Wieczorowski, Michał, Bartosz Gapiński, Karol Grochalski y Tatiana Miller. "Theoretical aspects of analysis of selected sources of errors in profile measurements of surface asperities". Mechanik 90, n.º 4 (10 de abril de 2017): 335–38. http://dx.doi.org/10.17814/mechanik.2017.4.53.

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In the paper theoretical background regarding selected errors in profile methods of surface asperities measurements were presented. The influence of a tip was discussed for stylus (including geometry, pressure and flight) and optical probe basing on confocal chromatic effect. Problems connected with translation tables was described. Basic assumptions regarding accuracy parameters in topographical analysis was shown.

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31

Bomphrey, Richard J., Toshiyuki Nakata, Per Henningsson y Huai-Ti Lin. "Flight of the dragonflies and damselflies". Philosophical Transactions of the Royal Society B: Biological Sciences 371, n.º 1704 (26 de septiembre de 2016): 20150389. http://dx.doi.org/10.1098/rstb.2015.0389.

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This work is a synthesis of our current understanding of the mechanics, aerodynamics and visually mediated control of dragonfly and damselfly flight, with the addition of new experimental and computational data in several key areas. These are: the diversity of dragonfly wing morphologies, the aerodynamics of gliding flight, force generation in flapping flight, aerodynamic efficiency, comparative flight performance and pursuit strategies during predatory and territorial flights. New data are set in context by brief reviews covering anatomy at several scales, insect aerodynamics, neuromechanics and behaviour. We achieve a new perspective by means of a diverse range of techniques, including laser-line mapping of wing topographies, computational fluid dynamics simulations of finely detailed wing geometries, quantitative imaging using particle image velocimetry of on-wing and wake flow patterns, classical aerodynamic theory, photography in the field, infrared motion capture and multi-camera optical tracking of free flight trajectories in laboratory environments. Our comprehensive approach enables a novel synthesis of datasets and subfields that integrates many aspects of flight from the neurobiology of the compound eye, through the aeromechanical interface with the surrounding fluid, to flight performance under cruising and higher-energy behavioural modes. This article is part of the themed issue ‘Moving in a moving medium: new perspectives on flight’.

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32

Stickland, M. T. y T. J. Scanlon. "A novel method for the provision of flight experience and flight testing for undergraduate aeronautical engineers at the University of Strathclyde". Aeronautical Journal 108, n.º 1084 (junio de 2004): 315–18. http://dx.doi.org/10.1017/s0001924000000178.

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Abstract The Department of Mechanical Engineering at the University of Strathclyde has developed a novel flight experience/test course for undergraduate Aeronautical Engineers. In common with similar courses at undergraduate level the course contains practical instruction in how an aircraft is flown, an analysis of its stall characteristics and an assessment of an aircraft’s performance and stability. However, uniquely, the Strathclyde course consists of dual instructional flights in two seat gliders. This paper contains a detailed description of the flight experience/test course developed at Strathclyde and its incorporation into the undergraduate curriculum. A critical analysis of its delivery is also presented.

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33

Nudds, Robert L. y David M. Bryant. "Consequences of load carrying by birds during short flights are found to be behavioral and not energetic". American Journal of Physiology-Regulatory, Integrative and Comparative Physiology 283, n.º 1 (1 de julio de 2002): R249—R256. http://dx.doi.org/10.1152/ajpregu.00409.2001.

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The doubly-labeled water technique and video were used to measure the effect of mass loading on energy expenditure and takeoff performance in zebra finches, Taeniopygia guttata, that were making routine (nonalarm) short flights. Finches that carried 27% additional mass did not expend more energy during flight than unloaded controls. Carrying additional mass, however, led to a reduced body mass and a decreased velocity during takeoffs (by 12%). Calculations of instantaneous mechanical power indicated that energy expended by unloaded and loaded finches at takeoff was similar, due to the observed decrease in velocity by mass-loaded finches and a lowering of their body mass. During routine short flights, zebra finches appear to maintain their metabolic power input and mechanical power output regardless of mass loading. Here, the costs of carrying additional mass during routine short flights were revealed to be behavioral and not energetic.

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34

KAWACHI, Keiji. "Flight Mechanics of Insect". Journal of the Visualization Society of Japan 20, n.º 1Supplement (2000): 5–10. http://dx.doi.org/10.3154/jvs.20.1supplement_5.

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35

Lee, J. Lawrence. "The Mechanics of Flight". Mechanical Engineering 122, n.º 07 (1 de julio de 2000): 54–59. http://dx.doi.org/10.1115/1.2000-jul-2.

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This article illustrates contribution of mechanical engineering in the aviation industry. The most obvious role of the mechanical engineer involves the design of engines. From the Wrights’ four cylinders, 12-horsepower engine, aircraft propulsion has evolved into today’s high-bypass turbofans developing over 90,000 pounds of thrust in some instances. The most visible contribution of mechanical engineers to aviation, engines are far from their only contribution. Changes in the design, construction, and capabilities of increasingly modern aircraft challenged the mechanical engineering in many other regards. The introduction of gas-turbine power required a concurrent revolution in manufacturing, test, and maintenance facilities and techniques at the engine builders. As advancements in aircraft construction and power opened the door to higher and faster flight, virtually every system within the airplane had to become more sophisticated, and new ones had to be devised. Air conditioning systems also changed, both to better suit the gas turbine prime mover and to accommodate wider external temperature extremes.

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36

Suzuki, K., I. Okada y M. Yoshino. "Effect of wing mass on the free flight of a butterfly-like model using immersed boundary–lattice Boltzmann simulations". Journal of Fluid Mechanics 877 (27 de agosto de 2019): 614–47. http://dx.doi.org/10.1017/jfm.2019.597.

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The wings of butterflies are relatively heavier than those of other insects, and the inertial force and torque due to the wing mass are likely to have a significant effect on agility and manoeuvrability in the flapping flight of butterflies. In the present study, the effect of wing mass on the free flight of butterflies is investigated by numerical simulations based on an immersed boundary–lattice Boltzmann method. We use a butterfly-like model consisting of two square wings with mass connected by a rod-shaped body. We simulate the free flights of the model by changing the ratio of the wing mass to the total mass of the model and also changing the mass distributions of the wings. As a result, we find that the aerodynamic vertical and horizontal forces decrease as the wing-mass ratio increases, since for a large wing-mass ratio the body has large vertical and horizontal oscillations in each stroke and consequently the speeds of the wing tip and the leading edge relatively decrease. In addition, we find that the wing-mass ratio has a dominant effect on the rotational motion of the model, and a large wing-mass ratio reduces aerodynamic force and intensifies the time variation of the pitching angle. From the results of our free flight simulations, we clarify the critical wing-mass ratio between upward flight and downward flight and find that the critical wing-mass ratio is a function of the non-dimensional total mass and almost independent of the wing length. Then, we evaluate the effect of the wing-mass distribution on the critical wing-mass ratio. Finally, we discuss the limitations of the model.

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37

Cao, Yakun, Chenping Zhu, Yanjun Wang y Qingyun Li. "A Method of Reducing Flight Delay by Exploring Internal Mechanism of Flight Delays". Journal of Advanced Transportation 2019 (30 de diciembre de 2019): 1–8. http://dx.doi.org/10.1155/2019/7069380.

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This paper explores the internal mechanism of flight departure delay for the Delta Air Lines (IATA-Code: DL) from the viewpoint of statistical law. We roughly divide all of delay factors into two sorts: propagation factor (PF), and nonpropagation factors (NPF). From the statistical results, we find that the distribution of the flight departure delay caused by only NPF exhibits obvious power law (PL) feature, which can be explained by queuing model, while the original distribution of flight departure delay follows the shift power law (SPL). The mechanism of SPL distribution of flight departure delay is considered as the results of the aircraft queue for take-off due to the airports congestion and the propagation delay caused by late-arriving aircraft. Based on the above mechanism, we develop a specific measure for formulating flight planning from the perspective of mathematical statistics, which is easy to implement and reduces flight delays without increasing operational costs. We analyze the punctuality performance for 10 of the busiest and the highest delay ratio airports from 155 airports where DL took off and landed in the second half of 2017. Then, the scheduled turnaround time for all flights and the average scheduled turnaround time for all aircraft operated by DL has been counted. At last, the effectiveness and practicability of our method is verified by the flights operation data of the first half of 2018.

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38

Makowski, Mirosław, Konrad Sienicki y Krzysztof Motyl. "Visualization of flight rocket missile in the environment Matlab/Simulink with the use of the FlightGear". Mechanik, n.º 7 (julio de 2015): 563/487–563/496. http://dx.doi.org/10.17814/mechanik.2015.7.264.

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39

Rogers, David F. "An Engineering Flight-Test Course Emphasizing Flight Mechanics Concepts". Journal of Aircraft 39, n.º 1 (enero de 2002): 79–83. http://dx.doi.org/10.2514/2.2898.

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40

Massey, K. C., J. McMichael, T. Warnock y F. Hay. "Development of mechanical guidance actuators for a supersonic projectile". Aeronautical Journal 112, n.º 1130 (abril de 2008): 181–95. http://dx.doi.org/10.1017/s0001924000002128.

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Abstract In this paper, the results of a series of experiments funded by DARPA to determine the feasibility of using small actuators to provide directional control for a supersonic projectile are presented. Controlling the flight of the projectile was accomplished by taking advantage of complex shock-boundary-layer interactions produced by mechanical devices. Experimental tests were conducted at GTRI to screen several control concepts and actuator locations. Further experiments were conducted on a scale projectile in a supersonic stream to investigate the rise time of the forces. Several different mechanical actuators were tested which served to provide guidance for future actuator designs. CFD results were also used to predict the results in flight as well as gain insights into the fluid mechanics involved. Flight tests of a Mach 4 round proved the viability of the guidance actuator.

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41

Sienicki, Konrad, Krzysztof Motyl y Piotr Zalewski. "Mathematical modeling and computer simulation of a flight air target with the use of a package MathCAD". Mechanik, n.º 7 (julio de 2016): 814–15. http://dx.doi.org/10.17814/mechanik.2016.7.187.

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42

AZUMA, AKIRA, SOICHI AZUMA, ISAO WATANABE y TOYOHIKO FURUTA. "Flight Mechanics of a Dragonfly". Journal of Experimental Biology 116, n.º 1 (1 de mayo de 1985): 79–107. http://dx.doi.org/10.1242/jeb.116.1.79.

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The steady slow climbing flight of a dragonfly, Sympetrum frequens, was filmed and analysed. By using the observed data, the mechanical characteristics of the beating wings were carefully analysed by a simple method based on the momentum theory and the blade element theory, and with a numerical method modified from the local circulation method (LCM), which has been developed for analysing the aerodynamic characteristics of rotary wings. The results of calculations based on the observed data show that the dragonfly performs low speed flight with ordinary airfoil characteristics, instead of adopting an abnormally large lift coefficient. The observed phase advance of the hindwing, Δδ1 ≃ 80° can be fully explained by the present theoretical calculation. Similarly, the spanwise variation of the airloading and the time variations of the horizontal force, vertical force, pitching moment and torque or power can be definitely estimated within a reasonable range of accuracy in comparison with the flight data. The distribution of loading between the fore and hind pairs of wings is also clarified by the calculations.

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43

Stollery, J. L. "Aerodynamics, Aeronautics and Flight Mechanics". Proceedings of the Institution of Mechanical Engineers, Part G: Journal of Aerospace Engineering 211, n.º 1 (1 de enero de 1997): 63–64. http://dx.doi.org/10.1177/095441009721100102.

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44

Ande, Robert C. "The mechanics of flight following". Hospital Aviation 5, n.º 7 (julio de 1986): 13. http://dx.doi.org/10.1016/s0740-8315(86)80151-6.

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45

Soares Júnior, Gilberto Gomes, Omar Ayub, Jose Carlos Gasparim, Luciana Maria Malosá Sampaio, José Celso Contador, Antônio Pires Barbosa, Sonia Francisca de Paula Monken, Mauro Luiz Martens, Cristina Dai Prá Martens y Walter Cardoso Satyro. "Impacts and effects of the use of medications by crew and passengers during air transport". Research, Society and Development 11, n.º 1 (11 de enero de 2022): e44011125251. http://dx.doi.org/10.33448/rsd-v11i1.25251.

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During a flight, changes occur in the human body, whose possible reactions can influence the well-being and quality of health of medicine users, subject of scarce studies. The aim of this paper is to analyze the impacts and effects of medication use during air transport. Through a literature review and documentary research methodology, relevant facts about the precautions that should be taken regarding the use of medication in flights were considered. As a practical contribution, some important medications and their possible effects during flights are presented, as well as some warnings about medication interactions, and some advice for better quality air travel for the health of passengers and crew are given. As a theoretical contribution, this study gathers the scattered information presented in the literature about the problems that the use of medications during a flight can cause to the human body and possible recommendations. As social contribution, this study warns about the risks of self-medication, and establishes a basis for future discussions with society about the use of medication in flights.

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46

Kennedy, R. S., G. O. Allgood, B. W. Van Hoy y M. G. Lilienthal. "Motion Sickness Symptons and Postural Changes following Flights in Motion-Based Flight Trainers". Journal of Low Frequency Noise, Vibration and Active Control 6, n.º 4 (diciembre de 1987): 147–54. http://dx.doi.org/10.1177/026309238700600402.

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Navy pilots flew over 193 standard training mission scenarios while acceleration recordings in three linear dimensions (gx, gy, and gz) were made for two moving-base flight trainers. The pilots, who were of comparable age and experience in both groups, were interviewed for motion sickness symptomatology and were tested for ataxia after leaving the simulators. The aircraft simulated included a P-3C turboprop fixed-wing patrol aircraft (2F87F), and an SH-3 antisubmarine warfare helicopter (2F64C). Motion sickness incidence was high in the SH-3 simulator and nonexistent in the P-3C. Ataxia scores indicated departures, though not significant, from expected learning curve improvements after exposure in both simulators. Spectral analyses of the motion recordings revealed significant amounts of energy in the nauseogenic region of 0.2 Hz in the SH-3 simulator in the gz and gy, but not in the gx. The levels exceeded those recommended for ship motion exposures by Military Standard 1472C. The P-3C simulator had low levels of energy in these regions, and well below recommended levels. The data are discussed from the standpoint that simulator sickness in moving-base simulation may be, at least in part, a function of exposure to frequencies that make people seasick.

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47

Paranjape, Aditya A., Michael R. Dorothy, Soon-Jo Chung y Ki-D. Lee. "A Flight Mechanics-Centric Review of Bird-Scale Flapping Flight". International Journal of Aeronautical and Space Sciences 13, n.º 3 (30 de septiembre de 2012): 267–81. http://dx.doi.org/10.5139/ijass.2012.13.3.267.

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48

Atallah, Stephanie y Susan Hotle. "Evaluation of Airport Size and Delay Causal Factor Effects on Delay Propagation Dissipation". Transportation Research Record: Journal of the Transportation Research Board 2676, n.º 3 (17 de noviembre de 2021): 608–20. http://dx.doi.org/10.1177/03611981211055663.

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The International Civil Aviation Organization identifies departure and arrival punctuality as on-time key performance indicators. However, these metrics assume a flight’s delay is a result of either the origin or destination airport, providing limited information on where delay should be mitigated in the U.S. National Airspace System (NAS). This study evaluates the relationship between delay propagation magnitude, delay causal factor, airport size, and charged facility (airport or Air Route Traffic Control Center), to examine if certain delays take longer to dissipate. First, using flights from July 2018, results show that most delay propagation chains originate at large-hub airports. However, these delays were the quickest to recover. Second, this study presents a regression model, predicting total propagated delay using fixed effects based on the weather region where the original delay occurred. Each additional flight affected by downstream delay adds 18.7 min on average to total arrival delay in a propagation chain. Additionally, if weather was the original causal factor, total propagated delay increased by 11.6 min compared with non-weather delays. Lastly, this study compares delay propagation in July 2018 and July 2020. Results show uneven impacts of the coronavirus disease 2019 (COVID-19) across the large-hub airports. Some of the investigated airports did not witness large improvements in average delay per delayed flight, warranting further research in the future. While delay and delay propagation have not been completely eradicated in the NAS during the COVID-19 pandemic, findings suggest that both have significantly declined on average.

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49

Kownacki, Cezary. "REAL FLIGHT DEMONSTRATION OF PITCH AND ROLL CONTROL FOR UAV CANYON FLIGHTS". Acta Mechanica et Automatica 7, n.º 3 (1 de septiembre de 2013): 148–54. http://dx.doi.org/10.2478/ama-2013-0025.

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Abstract The paper presents results of an experiment prepared to validate the autonomous control of obstacle avoidance designed for a micro UAV to fly in urban canyons. The idea of the obstacle avoidance assumes usage of two miniature laser rangefinders responsible for obstacle detection and range measurement. Measured ranges from obstacles placed on both sides of UAV can be used to simultaneous control of desired roll and pitch angles. Such combination of controls allows achieving high agility of UAV, because during a maneuver of obstacle avoidance UAV can make a turn and climb at the same time. In the experiment, controls of roll and pitch angles were verified separately to ensure high reliability of results and clearance of UAV behavior in the real flight. Because of lack of appropriate objects, which can be used as obstacles, laser rangefinders were directed vertically to the ground instead of the original horizontal configuration. So sensors determine ranges from the ground during a descent flight of UAV, and if their values are lower than defined threshold, it could be interpreted as obstacle detection. The experiment results present UAV behavior adequate to designed controls of roll and pitch angle. The vehicle turns in the opposite direction to the sensing axis of laser rangefinder detecting an obstacle and starts climbing when both sensors detect obstacles at the same range below the threshold.

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50

Shams, Taimur Ali, Syed Irtiza Ali Shah, Ali Javed y Syed Hossein Raza Hamdani. "Airfoil Selection Procedure, Wind Tunnel Experimentation and Implementation of 6DOF Modeling on a Flying Wing Micro Aerial Vehicle". Micromachines 11, n.º 6 (30 de mayo de 2020): 553. http://dx.doi.org/10.3390/mi11060553.

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Airfoil selection procedure, wind tunnel testing and an implementation of 6-DOF model on flying wing micro aerial vehicle (FWMAV) has been proposed in this research. The selection procedure of airfoil has been developed by considering parameters related to aerodynamic efficiency and flight stability. Airfoil aerodynamic parameters have been calculated using a potential flow solver for ten candidate airfoils. Eppler-387 proved to be the most efficient reflexed airfoil and therefore was selected for fabrication and further flight testing of vehicle. Elevon control surfaces have been designed and evaluated for longitudinal and lateral control. The vehicle was fabricated using hot wire machine with EPP styrofoam of density 50 Kg/ m 3 . Static aerodynamic coefficients were evaluated using wind tunnel tests conducted at cruise velocity of 20 m/s for varying angles of attack. Rate derivatives and elevon control derivatives have also been calculated. Equations of motion for FWMAV have been written in a body axis system yielding a 6-DOF model. It was found during flight tests that vehicle conducted coordinated turns with no appreciable adverse yaw. Since FWMAV was not designed with a vertical stabilizer and rudder control surface, directional stability was therefore augmented through winglets and high wing leading edge sweep. Major problems encountered during flight tests were related to left rolling tendency. The left roll tendency was found inherent to clockwise rotating propeller as ‘P’ factor, gyroscopic precession, torque effect and spiraling slipstream. To achieve successful flights, many actions were required including removal of excessive play from elevon control rods, active actuation of control surfaces, enhanced launch speed during take off, and increased throttle control during initial phase of flight. FWMAV flew many successful stable flights in which intended mission profile was accomplished, thereby validating the proposed airfoil selection procedure, modeling technique and proposed design.

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