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The purpose of this paper is the multi-disciplinary conceptual investigation of a propulsive fuselage (PF) aircraft layout allowing for new performance synergies through closely coupled propulsion/airframe integration. The discussed aircraft layout facilitates the ingestion of the fuselage boundary layer and the utilization of wake filling, thus eliminating a significant share of fuselage drag.

Based on consistent book-keeping standards for conventionally installed and highly integrated propulsion systems, key aspects of conceptualisation regarding airframe and propulsion system are presented. As a result of this, a PF aircraft configuration is proposed featuring a fuselage fan power plant in conjunction with two under-wing podded power plants. Parametric models for integrated aircraft and propulsion system sizing and performance analysis are discussed that are suitable for the consistent mapping of the characteristics intrinsic to a PF layout. In an initial benchmarking exercise, the vehicular efficiency potentials of the previously identified PF configuration are evaluated against an advanced conventional reference aircraft.

During benchmarking, it was found that a best and balanced design for the proposed PF aircraft layout yields an increase in vehicular efficiency of approximately 10 per cent compared to the advanced conventional reference aircraft.

The paper gives the reader an idea for the efficiency potentials achievable through a PF aircraft configuration, as well as guidelines for aircraft sizing and integrational aspects. It may serve as a basis for advanced studies in the future.

The conceptual investigation of the PF concept idea, contributes to establishing the initial technical feasibility of this novel approach to synergistic propulsion system integration. The methods presented in this paper allow for the multi-disciplinary conceptual design sizing of a PF aircraft.

Motivated by the potential of gaining noticeable improvements in vehicular efficiency, this paper aims to investigate the benefits attainable from introducing a more synergistic propulsion/airframe integration. In previous work, the concept of a boundary layer ingesting propulsor encircling the aft section of an axisymmetric fuselage was identified to be particularly promising for the realisation of aircraft wake filling, and hence, a significant reduction of the propulsive power required.

After reviewing the theoretical principles of the propulsive fuselage concept, a book-keeping and model matching procedure is introduced, which is subsequently used to incorporate the numerically computed aerodynamic characteristics of a propulsive fuselage aircraft configuration into a propulsion system (PPS) sizing and performance model. As part of this, design heuristics for important characteristics intrinsic to propulsive fuselage power plants are derived. Thereafter, parametric study results of the PPS are discussed, and the obtained characteristics are compared to those of a conventionally installed power plant. Finally, the impact of the investigated PPS on the integrated performance of a propulsive fuselage aircraft concept is studied, and the results are compared and contrasted to previously conducted analyses based on semi-empirical characteristics.

It was found that the aircraft-level benefit originally predicted based on semi-empirical methods could be confirmed using the numerically derived PPS design heuristics, specifically an improvement in vehicular efficiency of 10.4 per cent over an advanced conventional reference aircraft.

The approach presented in the paper may serve as a guideline when incorporating the results of high-fidelity aerodynamic methods into a PPS sizing and performance model suitable for aircraft-integrated assessment of a propulsive fuselage concept. The vehicular efficiency potentials offered through the synergistic PPS integration approach are highlighted.

The paper contributes to a deeper understanding of the characteristics of a boundary layer ingesting fuselage fan (FF) power plant relative to a conventionally installed PPS. In addition, a set of PPS design correlations are presented allowing for the integrated sizing of a FF power plant.

A Summary by Dr. Alexander Klemin of the Papers Presented Before the Fourteenth Meeting of the Institute held at Columbia University, New York, on January 29–31, 1946. AERODYNAMICS IN spite of increased wing loadings, the use of full span wing flaps has been delayed, because of inability to find a suitable aileron. The Development of a Lateral‐Control System for use with Large‐Span Flaps by I. L. Ashkenas (Northrop Aircraft), outlines the various steps in the aerodynamic development of a retractable aileron system well adapted to the full span flap and successfully employed on the Northrop P‐61. Included is a discussion of the basic data used, the design calculations made, and the effect of structural and mechanical considerations. Changes made as a result of preliminary flight tests are discussed and the final flight‐test results are presented. It is concluded that the use of this retractable aileron system has, in addition to the basic advantage of increased flap span, the following desirable control characteristics: (a) favourable yawing moments, (b) low wing‐torsional loads, (c) small pilot forces, even at high speed.

The purpose of this paper is to present the result of calculations that were performed to estimate the structural weight of the passenger aircraft using novel technological solution. Mass penalty resulting from the installation of the fuselage boundary layer ingestion device was needed in the CENTRELINE project to be able to estimate the real benefits of the applied technology.

This paper focusses on the finite element analysis (FEA) of the fuselage and wing primary load-carrying structures. Masses obtained in these analyses were used as an input for the total structural mass calculation based on semi-empirical equations.

Combining FEA with semi-empirical equations makes it possible to estimate the mass of structures at an early technology readiness level and gives the possibility of obtaining more accurate results than those obtained using only empirical formulas. The applied methodology allows estimating the mass in case of using unusual structural solutions, which are not covered by formulas available in the literature.

Accurate structural mass estimation is possible at an earlier design stage of the project based on the presented methodology, which allows for easier and less costly changes in designed aircrafts.

The presented methodology is an original method of mass estimation based on a two-track approach. The analytical formulas available in the literature have worked well for aeroplanes of conventional design, but thanks to the connection with FEA presented in this paper, it is possible to estimate the structure mass of aeroplanes using unconventional technological solutions.

Conceptual and preliminary aircraft concepts are getting mature earlier in the design process, than ever before. To achieve that advanced level of maturity, multiple multidisciplinary analyses have to be done, often with usage of numerical optimization algorithms. This calls for right tools that can handle such a demanding task. Often the toughest part of a modern design is handling an aircraft’s computational models used for different analysis. Transferring geometry and loads from one program to another, or modifying internal structure, takes time and is not productive. Authors defined the concept of a common computational model (CCM), which couples programs from different aerospace scientific disciplines. Data exchange between the software components is compatible, and multidisciplinary analysis can be automated to high degree, including numerical optimization.

The panel method was applied to aerodynamic analysis and was coupled with open-source FEM code within one computational process.

The numerical results proved the effectiveness of developed methodology.

Developed software can be used within the design process of a new aircraft.

This paper presents an original approach for advanced numerical analysis, as well as for multidisciplinary optimization of an aircraft. The presented results show possible applications.

This paper aims to deal with the experimental estimation of both longitudinal- and lateral-directional aerodynamic characteristics of a new twin-engine, 11-seat commuter aircraft.

Wind tunnel tests have been conducted on a 1:8.75 scaled model. A modular model (fuselage, wing, nacelle, winglet and tail planes) has been built to analyze both complete aircraft aerodynamic characteristics and mutual effects among components. The model has been also equipped with trailing edge flaps, elevator and rudder control surfaces.

Longitudinal tests have shown the goodness of the aircraft design in terms of aircraft stability, control and trim capabilities at typical clean, take-off and landing conditions. The effects of fuselage, nacelles and winglets on lift, pitching moment and drag coefficients have been investigated. Lateral-directional stability and control characteristics of the complete aircraft and several aircraft component combinations have been tested to estimate the aircraft components’ interactions.

The experimental tests have been performed at a Reynolds number of about 0.6e6, whereas the free-flight Reynolds number range should be between 4.5e6 and 9.5e6. Thus, all the measured data suffer from the Reynolds number scaling effect.

The study provides useful aerodynamic database for P2012 Traveller commuter aircraft.

The paper deals with the experimental investigation of a new general aviation 11-seat commuter aircraft being brought to market by Tecnam Aircraft Industries and it brings some material on applied industrial design in the open literature.

Under this heading are published regularly abstracts of all Reports and Memoranda of the Aeronautical Research Council, Reports and Technical Notes of the United States National Advisory Committee for Aeronautics and publications of other similar Research Bodies as issued

EFFORTS have been and are currently being made to improve the survivability of passengers where the decelerations experienced should not result in injuries which prevent escape from the cabin. All too often, inhalation of toxic fumes has been the cause of fatalities and measures recently incorporated are aimed to try and ensure that such a situation is most unlikely to arise. This is particularly relevant in the wake of the 1985 Manchester accident and the full report which is to be published soon, is expected to contain a considerable amount of information and further recommendations. Meanwhile it is worth looking at the full details available of the DC‐9 inflight fire which caused the aircraft to make an emergency landing at Cincinnati Airport, in so far as this concerns the conditions in the cabin and the survival and evacuation aspects.

Under this heading are published regularly abstracts of all Reports and Memoranda of the Aeronautical Research Council, Reports and Technical Memoranda of the United States National Advisory Committee for Aeronautics and publications of other similar Research Bodies as issued.