Program Overview: Vortex Interaction Aerodynamics Relevant to Military Air Vehicle Performance

2015 ◽

Cited By ~ 3

Author(s):

John Gerdes ◽

Hugh A. Bruck ◽

Satyandra K. Gupta

Keyword(s):

System Design ◽

Flapping Wing ◽

Wing Size ◽

Vehicle Performance ◽

Trade Offs ◽

Systematic Exploration ◽

Maximum Payload ◽

Air Vehicle ◽

Payload Capacity ◽

Improved Performance

The design of a flapping wing air vehicle is dependent on the interaction of drive motors and wings. In addition to the wing shape and spar arrangement, sizing and flapping kinematics affect vehicle performance due to wing deformation resulting from flapping motions. To achieve maximum payload and endurance, it is necessary to select a wing size and flapping rate that will ensure strong performance and compatibility with drive motor capabilities. Due to several conflicting trade-offs in system design, this is a challenging problem. We have conducted an experimental study of several wing sizes at multiple flapping rates to build an understanding of the design space and ensure acceptable vehicle performance. To support this study, we have designed a new custom test stand and data post-processing procedure. The results of this study are used to build a design methodology for flapping wing air vehicles with improved performance and to highlight system design challenges and strategies for mitigation. Using the methodology described in this paper, we have developed a new flapping wing air vehicle called the Robo Raven II. This vehicle uses larger wings than Robo Raven and flight tests have confirmed that Robo Raven II has a higher payload capacity.

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Helicopter icing

The Aeronautical Journal ◽

10.1017/s0001924000003559 ◽

2010 ◽

Vol 114 (1152) ◽

pp. 83-90 ◽

Cited By ~ 12

Author(s):

Y. Cao ◽

K. Chen

Keyword(s):

Cfd Simulation ◽

Simulation Methods ◽

Calculation Methods ◽

Vehicle Performance ◽

Wide Range ◽

Air Vehicle ◽

Alternative Means ◽

Numerical Simulation Methods ◽

Helicopter Aerodynamics ◽

Computational Fluid Dynamics Cfd

Abstract Due to constraints of natural condition, cost and of available time associated with model fabrication and for extensive wind-tunnel tests or flight tests, Computational Fluid Dynamics (CFD) simulation was considered an alternative means of providing air vehicle icing simulation and aeromechanic performance analysis. Full-scale icing experiments and, therefore, certification and cost can be significantly reduced by developing full-numerical simulation methods to evaluate the air vehicle performance for a wide range of icing conditions. This paper summarises helicopter icing simulation methods that include the development of helicopter aerodynamics, calculation methods of helicopter icing, icing protection system performance, icing effects on the helicopter performance, and some challenges in helicopter icing simulation.

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CVF ski-jump ramp profile optimisation for F-35B

The Aeronautical Journal ◽

10.1017/s0001924000002803 ◽

2009 ◽

Vol 113 (1140) ◽

pp. 79-85 ◽

Cited By ~ 6

Author(s):

A. Fry ◽

R. Cook ◽

N. Revill

Keyword(s):

Environmental Conditions ◽

Landing Gear ◽

Paper Briefly ◽

Aircraft Carrier ◽

Vehicle Performance ◽

Theoretical Profile ◽

Air Vehicle ◽

Aircraft Configurations ◽

Optimum Profile

Abstract This paper presents a summary of the principles and processes used to design a ski-jump ramp profile for the UK’s Future Aircraft Carrier (CVF) optimised for the Joint Strike Fighter (JSF). The paper includes an overview of the CVF and JSF programs, a history and summary of the ski-jump ramp and the principles of its use in the shipborne Short Take-Off (STO) manoeuvre. The paper discusses the importance of defining optimisation boundaries including specified objectives, aircraft configurations and environmental conditions. It then demonstrates the process of balancing the design drivers of air vehicle performance and landing gear loads to achieve an optimum profile. Comparisons are made between the proposed candidate CVF ramp profile and the current in service ski-jump design as designed for the Harrier family of aircraft. The paper briefly covers some of the important issues and factors that have been experienced when a theoretical profile is translated into a physical ramp fitted to a ship, principally the effects on aircraft operations due to build and in-service variation from the nominal profile.

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