Recent advances in computing subsonic flow have been applied to helicopter configurations with various degrees of success. This paper is a comparison of two specific methods applied to a particularly challenging regime of helicopter flight, very low speeds, where the interaction of the rotor wake and the fuselage are most significant. Comparisons are made between different methods of predicting...

A method to intended for measurement of the insertion loss of an acoustic treatment applied to an aircraft fuselage in-situ is documented in this paper. Using this method, the performance of a treatment applied to a limited portion of an aircraft fuselage can be assessed even though the untreated fuselage also radiates into the cabin, corrupting the intensity measurement. This corrupting noise ...

Procedures for automatic computation of wing-fuselage juncture geometry are described. These procedures begin with a geometry in wavedrag format. First, an intersection line is computed by extrapolating the wing to the fuselage. Then two types of lleting procedures are described, both of which utilize a combination of analytical and numerical techniques appropriate for automatic calculation. An...

A numerical study is presented of the residual strength of an aircraft fuselage in the presence of multiple site damage (MSD)/muItiple element damage. The analyses were carried out using a software package that was developed to facilitate automated analyses of full-scale fuselage panels with widespread fatigue damage, using a hierarchical approach and elastic-plastic finite element alternating ...

The US Army Aeroflightdynamics Directorate (AFDD), the French Office National d’Etudes et de Recherches Aérospatiales (ONERA) and the Georgia Institute of Technology (GIT) are working under the United States/France Memorandum of Agreement on Helicopter Aeromechanics to study rotorcraft aeromechanics issues of interest to both nations. As a task under this agreement, a comparative study of the D...

This paper describes a conceptual design of fuselage structure for very light jet aircraft by using CAD software as the design tool. Specific size and performance, the number of competing designs and the commonality of features with existing light jet aircraft are factors need to be considered in the design process. This conceptual design develops the first general size and configuration for a ...

Substandard fuselage can trigger a deadly disaster that may claim many lives. This paper proposes employing of a standard digital camera that can produce JPEG images in an attempt to pinpoint a scratch in a fuselage. The digital camera takes pictures of the fuselage. The signal processing scheme of JPEG takes for granted that the taken picture is pretty smooth. Accordingly, when there is an abr...

In order to enhance the aircraft survivability, the infrared signatures emitted by hot engine parts should be determined exactly. For its reduction it is necessary for the rear fuselage temperature to be decreased. In this study, numerical modeling of flow fields and heat transfer characteristics of an aircraft nozzle is performed and its temperature distribution along each component wall is pr...

This paper presents a modified nonlinear longitudinal model for an air-breathing hypersonic vehicle and the design of an L1 adaptive controller for it. It is assumed that the mid-fuselage is a rigid-body, while the aft-fuselage is linearly elastic, and a rigid all-movable elevator is fixed at the end of the aft-fuselage. In the resulting mathematical model, the pitching moment depends not only ...

Trans World Airlines (TWA) flight 800 was only twelve minutes into a July 19, 1996 trip from New York to Paris when an in-flight explosion destroyed the passenger jet, plunging it into the Atlantic with 230 people on board. The aircraft was climbing south of the Long Island coast near East Moriches, New York when suddenly, portions of the Boeing 747-131 fuselage beneath the center wing fuel tan...