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1 – 5 of 5Daniel Lichoń, Andrzej Robert Majka and Tomasz Lis
The purpose of this paper was to elaborate the performance model of the remotely piloted aircraft systems (RPAS) which was destined for simulations of the construction…
Abstract
Purpose
The purpose of this paper was to elaborate the performance model of the remotely piloted aircraft systems (RPAS) which was destined for simulations of the construction characteristics, airspeeds and trajectory of flight in the controlled, non-segregated airspace according to the standard instrument departure and arrival procedures (SIDs and STARs).
Design/methodology/approach
This study used systems engineering approach: decomposition of RPAS performance model into components, relations and its connection with components of controlled the airspace system. Fast-time simulations (FTS) method, which included investigation of many scenarios of the system work, minimizing the number of input variables and low computing power demand, is also used.
Findings
Performance envelope of many fixed-wing RPAS was not published. The representative RPAS geometry configuration was feasible to implement. Power unit model and aerodynamic model needed to be accommodated to RPAS category. The range of aircraft minimum drag coefficient differed in the investigated range of take-off mass and wing loading.
Research limitations/implications
Fixed-wing RPAS of small and medium categories cover take-off mass (25–450 kg), wing loading (40–900 N/m2) and power loading (8–40 W/N).
Practical implications
This is a research on integration of the RPAS in the controlled, non-segregated airspace. The results of the work may be used in broadening the knowledge of the RPAS characteristics from the perspective of operators, designers and air traffic services.
Originality/value
The elaborated performance model of the RPAS used the minimum number of three input variables (take-off mass, wing loading and power loading) in identification of the complete RPAS characteristics, i.e. construction features (aerodynamic, propulsion and loads) and flight parameters (airspeeds and flight trajectory).
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Sławomir Samolej, Grzegorz Dec, Dariusz Rzonca, Andrzej Majka and Tomasz Rogalski
The purpose of this study is to provide an alternative graph-based airspace model for more effective free-route flight planning.
Abstract
Purpose
The purpose of this study is to provide an alternative graph-based airspace model for more effective free-route flight planning.
Design/methodology/approach
Based on graph theory and available data sets describing airspace, as well as weather phenomena, a new FRA model is proposed. The model is applied for near to optimal flight route finding. The software tool developed during the study and complexity analysis proved the applicability and timed effectivity of the flight planning approach.
Findings
The sparse bidirectional graph with edges connecting only (geographically) closest neighbours can naturally model local airspace and weather phenomena. It can be naturally applied to effective near to optimal flight route planning.
Research limitations/implications
Practical results were acquired for one country airspace model.
Practical implications
More efficient and applicable flight planning methodology was introduced.
Social implications
Aircraft following the new routes will fly shorter trajectories, which positively influence on the natural environment, flight time and fuel consumption.
Originality/value
The airspace model proposed is based on standard mathematical backgrounds. However, it includes the original airspace and weather mapping idea, as well as it enables to shorten flight planning computations.
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The purpose of the paper is to determine the optimal conditions of the take-off and the optimal trajectory of the initial climb minimizing the fuel consumption of the aircraft…
Abstract
Purpose
The purpose of the paper is to determine the optimal conditions of the take-off and the optimal trajectory of the initial climb minimizing the fuel consumption of the aircraft aided in the ground phase of the take-off by the system using the MAGLEV technology.
Design/methodology/approach
The study concerned determining the optimal trajectory of the initial phase of the transport aircraft climb aided in the phase of acceleration by the system using the magnetic levitation phenomenon. The simplified algorithm of the Ritz–Galerkin method was used in this work which uses an approximate solution to boundary value problems for determining the optimal flight trajectory. It uses the method of approximation of the flight path by the third-degree polynomial. The method allows determining the optimal trajectory of the flight satisfying the initial/final conditions and control functions and path constrains for an aircraft. General stating of the task supposes determining the optimal trajectory of movement of a flying vehicle described by the system of ordinary differential equations. The resulting sparse non-linear programming problem has been solved using own elaborated software. The typical profiles computation has been performed with a tool combining three degree of freedom flight dynamics differential equations with procedure-oriented flight control.
Findings
Different conditions of the take-off of the aircraft aided by the ground system using the MAGLEV technology give possibilities to shape the trajectory of the initial stage of the aircraft climb after the lift-off to decrease the negative influence on the environment. Optimization of the departure trajectory minimizing fuel consumption or noise emissions can become the basis for working out new procedures for a new kind of take-off modified in relation to the optimal solution which will increase the safety of this segment of the flight.
Research limitations/implications
The analysis was carried out only for the departure trajectory to minimize fuel consumption, without investigation of possibilities of noise reduction. The trajectory guaranteeing minimization of the fuel consumption would also give a solution characterized by minimal emission of substances harmful for the environment.
Practical implications
Application of the innovatory solution of aided take-off is connected with modification of the climbing procedures after the take-off to minimize the negative effect of the aircraft on the surrounded environment. The results can become the basis for working out new procedures which will minimize negative influence to the natural environment in the vicinity of the airports of air transport and increase safety of the take-off and landing operations.
Originality/value
Innovative method of the take-off implies new shape of the trajectory. The study presents the results of the climb trajectory optimization of the aircraft supported at the ground stage by the technology using magnetic levitation phenomenon.
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The purpose of this paper is to propose a solution of the engine bypass ratio choice problem of a very light jet (VLJ) class aircraft using the multiple objective optimization…
Abstract
Purpose
The purpose of this paper is to propose a solution of the engine bypass ratio choice problem of a very light jet (VLJ) class aircraft using the multiple objective optimization (MOO) method.
Design/methodology/approach
The work focuses on the choice of one of the most essential parameters of the jet engine, that is its bypass ratio. The work presents the methodology of optimal designing using the multitask character of the matter which is based on the mathematical model of optimization in the concept of the set theory. To make an optimal choice of the chosen parameter, a complete computational model of an aircraftwas made (aerodynamic, power unit, performance and cost) and then the method that allows to choose the bypass ratio was selected, regardingmultiple estimating criteria of the obtained solutions. The presented method can be used at the concept design state for determining the chosen and most important technical parameters of the aircraft.
Findings
The way to design a competing aircraft is to choose its design parameters, including the power unit, by using the advanced methods of MOO. The main aim of the work was to demonstrate a method of selecting chosen parameters of the transport aircraft at the preliminary design stage. The work focuses on the choice of bypass ratio of the jet engine of the VLJ. The method could be helpful at the preliminary design stage of a new aircraft to selection of other design parameters.
Research limitations/implications
The exemplary calculations were made for 50 different transport tasks to take into account different performance conditions of the aircraft. The presented method can be used at the concept design state for determining the chosen and most important technical parameters of the aircraft.
Practical implications
The work shows a practical possibility to implement the proposed method. The presented method could be helpful at the preliminary design stage of a new aircraft to select its design parameters. The results of the analyses are a separate point for further research and studies.
Originality/value
The work shows a practical possibility to implement the proposed approach for design problems at early stages of product development.
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The purpose of the paper is to analyze changes in the selected characteristics of an aircraft aided by a ground-based system using magnetic levitation (MAGLEV) to support safe…
Abstract
Purpose
The purpose of the paper is to analyze changes in the selected characteristics of an aircraft aided by a ground-based system using magnetic levitation (MAGLEV) to support safe take-off.
Design/methodology/approach
The analysis of the mass characteristics of the main aircraft units with conventional constructing solutions was carried out in this paper. It allowed determining the mass of these units and verifying the obtained results on the basis of the known examples. Thanks to such an approach it was possible to determine the mass of the aircraft modified for the requirements of the ground and on-board system for support of the aircraft safe take-off and landing (GABRIEL) system taking into account the change in the weights of the modified units (fuselage, wings, power unit, landing gear, etc.). The weight of the aircraft in its basic version was determined on the basis of the common knowledge and methods described in the scientific literature which are based on the statistical analysis. The weight of the modified units for the needs of the GABRIEL system was determined on the basis of similar formulas taking into account the constructional changes in the airframe. The thrust required of the power unit was determined on the basis of the analysis of the steady state of the horizontal flight for the calculating aerodynamic characteristics determined by conventional methods. The characteristics in the take-off phase were determined solving the equation of motion of the aircraft influenced by the aerodynamic, electrodynamic forces and the forces that come from the power unit.
Findings
The preliminary analysis shows that the take-off aid system that uses the phenomenon of MAGLEV is possible to be created using the present-day technology. However, the costs of its realization would make it economically unproved. But it could increase safety and reduce harmful influence on the environment caused by taking-off and landing aircrafts.
Research limitations/implications
The analysis was carried out only for one chosen version of the solution which according to the author has the greatest chance to succeed. At the present-day state of the art, it seems problematic to use the proposed system to aid landing.
Practical implications
The work shows a practical possibility to implement the proposed solution. The results of the analyses are a separate point for further research of similar systems.
Originality/value
The work presents one of the aspects of the potential application of the innovatory conception of take-off and landing aid of transport aircrafts by the ground-based system using the MAGLEV technology.
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