The Tailless Aircraft

The Tailless AircraftThis overlay on quest afterless aircraft presents the pros and cons of using such an aircraft design for commercial purposes. The line comprises 4 sections discussing the aerodynamics, structural innovations, engines and overall advantages and disadvantages of tailless aircraft. The aerodynamic study of a tailless aircraft highlights the importance of the wave drag and span lode distribution and contrary designs that can improve the aerodynamic performance effectively. In structural innovations, several existing tailless aircraft are examined to identify how the structures have been designed to create a successful aircraft. In particular, structures used in the control and stability of the aircraft are examined. As regards to engines, the positioning of the engine and the idea of using a Vertical takeoff has been discussed. The advantages and disadvantages of a tailless aircraft have been detailed.IntroductionOf the aircraft in use today, the vast majority use a tailplane to house rudder and elevators. Aircraft without such a system of rules remain quite rare. However, the concept of tailless aircraft has long been considered by engineers and aviators as an aerodynamically ideal. In the history of the aircraft design several attempts were made to build an aircraft with reduced tail size which has sometimes resulted in smaller drag and weight but has added to controllability problems. Because of this, tailless designs have mostly been used in military applications. In this invoice we assess whether it is now possible to seriously use this concept in commercial aircraft.MethodologyThe information contained in this report was primarily gathered from textbooks and meshing research. Four different aspects of the subject were identified and each aspect was researched and written up by one member of the group. Additionally, the group were able to examine a harrier jump jet which visited Perth on 7th May 2010.Results of findingsThe followi ng table summarises what the research has revealedNegative pointsLower profile and interference drag fire to drag ratio increases by 20-25%Engines can be positioned in the centre rear instead of a tail, providing the additional advantage of directional stability set out control is more efficient due to large wingspanThe tip of the wing aerofoil is not near the stall angle due to inverse sweep along with twisted wing tipVertical takeoff is not practical since a large commercial aircraft weighs too much for the get-up-and-go available from current engine technology to overcomeDirectional control is more difficult to achieve without adding a rudder assemblyThe triangular spanwise aerodynamic loading distribution does not give the best aerodynamic performance even though the wave drag is the reduced.Section 1 AerodynamicsThis section of the report discusses the aerodynamics of a tailless aircraft and various instruments affecting the same. A tailless a is a revolutionary conceptual c hange from the classical design that has been prevalent for the past 50 years i.e. a wing attached to a cylindrical fuselage with a tail to ensure the stability and manoeuvrability of the aircraft.Lower wetted force field (area which is in contact with the external airflow) to volume ratio and lower interference drag is the main aerodynamic advantage of a tailless aircraft in par with the conventional aircraft.On the aerodynamic performance side, the maximum lift-to-drag ratio depends on the ratio of the aircraft span to the square root of the product of the induced drag factor and the zero-lift drag area, which is proportional to the wetted area of the aircraft.() max =Where Cf is the average friction co-efficient (mainly dependent on the Reynolds upshot) over the wetted area Swet and is the friction co-efficient.Since the tailless aircraft have a lower aspect ratio but also a lower friction co-efficient due to its larger chord, we always get smaller relative wetted area. This provides a substantial improvement in aerodynamic performance by increasing the lift-to-drag ratio of tailless aircraft in cruise to about 20-25% as compared to the conventional aircrafts.The BWB-450 and BWB-800 were designed to compare with the existing fleet of conventional aircrafts as Boeing 747 and Airbus 380. BWB-450 was presented with the span and the aspect ratio being reduced to 80 m and 7.55 respectively, thereby concluding a decrease in 30%fuel burn per seat for the BWB models as compared to other conventional aircrafts and thus requiring 3 instead of 4 engines.Moreover another(prenominal) such design project was successfully completed, which is based on a similar payload and performance as Airbus 380 with over 650 passengers. The configuration of the project is headspring suited for the application of laminar flow technology (which results in skin friction drag) to the engine Nacelle and potentially to the lifting surfaces. Also an increase in cruise Mach number increas es the drag making the design of aircraft unfeasible.