Introduction:Group design projects enable students to employ their relevant technical and personal competences for completion of the project according to the desired requirements. The following report is presented for illustrating the purpose of designing an Amethyst Glider Tail and the progress of the project. The specific insights into the subject matter for the project of designing a glider tail alongside its relevance to the objective of completing the glider design. Gliders have been considered as one of the flying machines without the requirement for engines and were introduced in Germany post the First World War(Alcántara-Salinas, Ellen & Rivera-Hernández, 2016).
The design of gliders has been a major subject of interest to various researchers on the grounds of its effectiveness in describing the principles of aerodynamics. The research design project for fabricating the Amethyst Glider Tail could be considered relevant in order to develop novel approaches for construction. The preferences for building a glider as the individual design solution could be based on the limited requirements of industrial facilities or complex technical equipment and substantial financial support. The report would also be directed towards presenting an illustration of the aims and objectives of the project and the specific deliverables that should be provided at the completion of the project. Other essential highlights which have been presented in the report would include the personal accomplishments and roles assumed by the author in the group design project that can reflect on the achievements, executed tasks and the variety of problems faced during the project duration(Balk, 2016).
The discussion on the existing status of the project would provide opportunities for recognizing any pitfalls as well as specific advantages involved with the project which enhances the probabilities for addressing unresolved issues. The report also aims to describe the technical competence aspects through a review of the appropriate learning principles for analyzing the scientific and technical factors related to design of a glider.Aims and objectives:Since it is clear that the design of gliders has provided ample prospects to investigate aerodynamics in depth alongside obtaining insights into the cost effective design of flying machines, the aim of the amethyst glider tail research project would be inclined towards obtaining a lucid impression about the design of glider tails and their variations. The objectives of the research activity would be aligned with a review of the theoretical impression regarding types of glider tails and the relevant purposes of the tail designs. The following report also has the objective of recognizing technical competences that can be contributed to the design of the glider tail including an impression of the scientific and technical factors related to the configuration of the glider tail(Foster, 2016). The report objectives are also directed towards understanding the personal competences through identifying individual contributions to the project. Furthermore, the glider tail research would also provide options for reforms in design considerations for suiting diverse objectives.
The learning outcomes from the project would also be inclined towards explanation of the advantages and pitfalls of the individual glider tail designs thereby implying the feasibility for introducing unprecedented design changes according to the final outcome desired from the glider(Gilad Silver, 2014). Current status of the project is observed in completion of the wing design and the following activity would be directed towards description of the primary functions of a tail, basic aspects related to the performance and techniques of the glider tail. The objective of understanding design changes could be presented in the form of a description of procedures for vertical and horizontal tail. The function of the horizontal and vertical tail in a glider is for lifting purposes and the distinct name is responsible for differentiating it from other components such as elevator, rudder and aileron(Greer, 2015). The parameters that should be followed in tail design are similar to that of the case of wing design and include examples such as angle of attack, airfoil and planform area. The primary function of tail is to generate a specific share of surface lifting by using partial capability.
It is also imperative to observe that the glider tail is also known as empennage and in a conventional glider design the tail could be classified into vertical and horizontal tail on the basis of their primary functions such as longitudinal and directional stability and trim. Furthermore, the function of control should also be attributed to glider tail since the control surfaces such as the rudder and elevator are important parts of the tail. The horizontal tail has to be designed for supporting longitudinal trim that is otherwise known as balance or equilibrium while the vertical tail serves the purpose of directional stability. The longitudinal trim from the horizontal tail is intended to counter the negative moment derived from the summation of the different pitching moment about y axis which is facilitated in the form of a negative lift(Roberts, 2017). Therefore, the setting angle in the case of horizontal tail is found to be negative. Vertical tail could facilitate lateral or directional trim especially in situations where one of the engines is not operative and a yawing moment is required for balancing the aircraft in response to the unstable moment created by the active engines. Glider tail is also responsible for the function of stability and therefore the vertical tail has to serve the function of directional stability and the horizontal tail ensures longitudinal stability.
Atmospheric phenomena such as heavy gusts of wind could lead to potential issues with the stability of the glider and hence the stability requirements are considered as mandatory inclusions in the list of tail design requirements(Ruthnick, 2013). The glider tail research activity should also focus on the significance of control as a primary function which is facilitated by the individual parts attached to horizontal and vertical tails such as elevator and rudder. The facilities of directional and longitudinal control should be included in the glider design in order to ensure that the trim conditions could be changed effectively. Personal contributions:The report also enabled the reflection on personal roles and responsibilities from a critical perspective thereby obtaining a clear impression of the existing status of the project, problems encountered in the course of the individual design solution project and the specific solutions proposed for the issues.
As per Thompson (2105), the personal contribution to the project was vested in logging the project events and obtain considerable amount of secondary research on glider tail design(Thompson, 2015). The requirement of specific emphasis on the details related to the functions of glider tail and the various advantages that could be garnered through the use of tails in a glider design was perceived in the possibilities for design reforms according to the objectives. The identification of specific functions of glider tail would enable the comparison of final outcomes of the glider design with the standard performance objectives of a glider. The recording of the project events in documented logs facilitates the opportunity for gaining insights into theoretical perspectives on aerodynamics employed in the design of the glider. However, it is essential to reflect on the research carried out on tail configuration which could be helpful for illustrating design requirements as well as the appropriate design information required for selecting a specific tail configuration. The requirement for reviewing tail configuration is important as the first stage of tail design has to be associated with selection of an appropriate tail configuration(Vodenska, 2013). Tail configuration is determined through a selection process without the requirements for mathematical calculation which reflects on the importance of factors such as evaluation, reasoning and logic for comparing the available configurations with the specified design requirements. According to Zervos (2013), the design requirements which are considered as significantly influential factors on the selection of tail configuration include survivability, market competitiveness, size limits, longitudinal, directional and lateral stability and trim, handling qualities, operational requirements, cost, safety, airworthiness and the flexibility for manufacturability and controllability(Zervos, 2013).
The tail configuration is determined only after reviewing the technical specifications of all the design requirements. In certain cases, it has been identified that a single configuration could not address all design requirements thereby implying the use of systems engineering approach for reaching on the final selection. As per Thompson (2015), the application of systems engineering approach is often considered responsible for exclusion of certain design requirements such as lateral stability in order to accomplish effectiveness of other design requirements such as stealth requirements or airworthiness(Thompson, 2015).
The different tail configurations which are found to address the design requirements in specific approaches can be classified into aft tail, canard tail with combinations of aft vertical tail and twin wing vertical tail as well as the tailless and triplane gliders and without any formal tail. The basic types of tail configurations include references to the T-tail, V-tail and conventional design. The conventional tail is known for the characteristic design feature wherein the horizontal and vertical stabilizers are intersecting at the fuselage thereby facilitating reasonable advantages of stability. As per Roberts (2017), the significant disadvantage associated with the conventional tail design could be identified in the interference of flow over the tail control surfaces caused due to the wake from wing at certain flight altitudes. The proximity of the horizontal stabilizer to the ground could also be accounted as a critical gap in the structural efficiency of a glider tail since it could be damaged even by slightest contact with objects on the ground in scenarios of off-field landing(Roberts, 2017). The T-tail design implies the placement of the horizontal stabilizer above the vertical stabilizer which presents advantage in the form of reduced threat from the wake of the wing at specific flight attitudes or in case of off field landing. This tail configuration is critiqued n the grounds of requirement for increasing the strength of the rear of fuselage and the vertical stabilizer thereby indicating an increase in weight of the glider.
The V-tail configuration is characterized by the prominent advantage of protection from damages in off-field landings through designing majority of the tail surface away from ground. The mixed controls for pitching and yawing could be considered as the major disadvantage in case of the V-tail configuration(Gilad Silver, 2014). Technical competences:An illustration of the technical competences with respect to the individual design solution research project for Amethyst glider tail could be presented through understanding the design requirements and feasible configurations and the specifications of individual design configurations. The general formats of tail configuration used in the design of aircrafts in the contemporary environment are the aft, canard and unconventional design formats. It is also interesting to focus on the knowledge of designing glider without tail configurations as a technological competence required for the design research project.
The use of automatic control systems and other components can be productive for gliders without any tail configuration(Thompson, 2015). In such cases examples of hang gliders could be presented which imply the realization of longitudinal trim by the pilot through body movement that leads to alteration in the glider’s centre of gravity. Longitudinal stability requirements should also be identified from the critical review of secondary research in order to present technical competences for the group design project. The aft tail configuration is selected for the design project albeit with the requirement for identifying the particular sub-configuration on the basis of comparative review of the advantages and design requirements.
The deeper reflection on the three particular configurations would have to be presented in the technical competences for finalizing an appropriate tail configuration for the Amethyst glider tail research project. The analysis of the performance of the conventional tail does not involve any complicacies owing to the simplicity of the configuration of conventional tail alongside reflecting on the flexibility for performing different tail functions such as control, stability and trim(Gilad Silver, 2014). The technical factors associated with the design could be illustrated in the form of the basic design implemented in the configuration such as the components of vertical and horizontal tail with the latter having two sections on left and right while the former is located over the aft fuselage. This type of tail configuration is required for novice designers or researchers with limited experience in glider design and is also accepted in majority of textbooks implying its general acceptance in glider designs. The advantages of the conventional tail configuration are identified in the efficiency, lightweight and flexibility of performance in regular flight conditions. Furthermore, it has been preferred due to the requirements of expert support and involvement in case of selecting other tail configurations for addressing the areas of control analysis, trim analysis and stability analysis(Foster, 2016).
The review of the T-tail configuration could also be accounted as an interpretation of the technical factors that could be evident in the project. The location of the vertical tail with respect to the horizontal tail is considered as the characteristic feature in a T-tail configuration. The productive features that could be identified in the T-tail include the limitations of complaints regarding wing wake, wing vortices and wing downwash. The T-tail is also responsible for reducing the impact of engine exit flow which could harm the glider with hot and turbulent high speed gas(Alcántara-Salinas, Ellen & Rivera-Hernández, 2016). The smaller horizontal tail area is also indicative of the lesser impact of engine on tail vibration thereby limiting the complaints of tail fatigue.
The positive elements of the T-tail configuration are also identified in the end-plate effect wherein the horizontal tail is responsible for moderating the vertical tail area. On the contrary, the T-tail configuration is characterized by certain disadvantages also which must be analyzed prior to the selection of a suitable tail configuration for the Amethyst glider tail research design project. The two prominent pitfalls could be recognized in the form of increased weight of the vertical tail due to reduction in area and deep stall caused due to higher angle of attack than the initial stall angle. The deep stall condition is considered potentially fatal due to the continuously escalating rate of descent despite the longitudinal stability that implies the reduction in effectiveness of the elevator and aileron(Thompson, 2015). However, design modifications such as stabilizing the pitch down in the initial stall, introducing mechanism for enabling full down elevator angles and extension of the horizontal tail span. Another significant tail configuration which could be utilized for the glider tail research design is the V-tail which is characterised with two distinct sections and can be considered similar to the conventional tail configuration albeit without a vertical tail and a high anhedral angle.
The two individual sections of the V-tail are accountable for the functions of the horizontal and vertical tails which enables it to perform the objectives of longitudinal and directional trim. On the contrary, the V-tail configuration is also considered responsible for inefficiency in monitoring the directional and longitudinal stability. The slanted tail surfaces are responsible for providing the functionalities of the elevator and rudder configuration implemented in a conventional tail. This leads to another considerable disadvantage in context of the V-tail configuration since the complexity of the control systems for a glider are increased considerably in the tail configuration(Gilad Silver, 2014). The calculations of the flight test results for the Amethyst Glider can be presented in the form of four distinct tests which involves collection of data related to distance and flight time.
The basic constants that are implemented in the case of the flight tests include the total glider weight estimated at 0.15 kg and height from ground as 1.98 m denoted by ‘h’. The flight attempts are considered invalid according to the BMFA A/2 class F1A rules owing to the flight time being less than 10 seconds. On the other hand, ignoring the basic consideration for 10 seconds flight time for calculating the average flight speed still depicts that the flight attempt would be unsuccessful according to the 3.1.6.
2.c. according to the BMFA Free Flight Rules. The Average Flight Speed calculated was found to be 5.003 and the improvement of glider’s performance could be accomplished through installing an aerofoil that can accomplish higher speeds than 5 m/s. The coefficient of lift was estimated by considering two constants such as wing span and cord length at 1.245 m and chord length at 0.
104 m. The coefficient was estimated to be 0.1937. Discussion and conclusion:The discussion presented in the report were largely directed towards understanding the categorization of tail types used in glider design, the specific tail configurations used commonly and the effectiveness of individual configurations. According to Vodenska (2013), the existing status of the Amethyst glider tail research is limited to the construction of wing design.
The deliverables required from the design solution project include a design of the preferred tail configuration that could address the objectives of understanding the various implications of aerodynamics in the design of glider tail(Vodenska, 2013). Since the project is aimed at designing a glider with minimal experience in design, the preferences for conventional tail configuration could be validated owing to the limited requirements of technical expertise in order to moderate the levels of trim, stability and control. However, future work in this domain should be based on critical inferences regarding static and dynamic stability of glider and the control aspects of the glider in order to derive unconventional tail designs that can facilitate feasible opportunities for presenting efficient glider designs with limited concerns for issues such as deep stall or rolling tendencies and higher drag(Zervos, 2013). The report reflected on the individual design solution project for Amethyst glider tail research and employed secondary research to derive inferences regarding the final tail configuration according to certain design requirements and a comparative review of advantages and pitfalls of individual types of tail configurations.