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This paper aims to create a terminal area operations (TAO) analysis software that can accurately appreciate the nuances of hybrid electric distributed propulsion (HEDP), including unique failure modes and powered-lift effects.

The program was written in Visual Basic with a user interface in Microsoft Excel. It integrates newly defined force components over time using a fourth order Runge-Kutta scheme.

Powered-lift, HEDP failure modes and electrical component thermal limitations play significant roles on the performance of aircraft during TAO. Thoughtful design may yield better efficiency; however, care must be given to address negative implications. Reliability and performance can be improved during component failure scenarios.

This program has and will support the investigation of novel propulsion system architectures and aero-propulsive relationships through accurate TAO performance prediction.

Powered-lift and HEDP architectures can be employed to improve takeoff and climb performance, both during nominal and component failure scenarios, however, reliance on powered-lift may result in faster approach speeds. High-lift and system failure behavior may also allow new approaches to design and sizing requirements.

This program is unique in both the public and private sectors in its broad capabilities for TAO analysis of aircraft with HEDP systems and powered-lift.

The purpose of this paper is to highlight and discuss the unique safety and protection requirements for the electrical microgrid system in a turboelectric distributed propulsion aircraft.

The NASA N3-X concept aircraft requirements were considered. The TeDP system was decomposed into three subsystems: turbogenerator, distribution system and propulsors. Unique considerations for each of these subsystems were identified.

The fail-safe requirements for a TeDP system require a divergence from the standard safety case used for conventional propulsion systems. Advantages in flight control and single-engine-out scenarios can be realized using TeDP. Additionally, a targeted use of energy storage and reconfigurability may enable seamless response to propulsion systems failures.

The concepts discussed in this paper will assist to guide the early conceptual and preliminary design and evaluation of TeDP architectures.

The safety case for TeDP architectures is currently immature. The work presented here acts to frame some of the major issues when designing, evaluating and verifying TeDP conceptual architectures.

COMMERCIAL air transport is a major growth industry. This growth, although fundamentally due to economic and political trends, has been greatly accelerated by the technological advance of aero engines and airframes.

BETWEEN May 18 and 26, airline experts from the United States, Australia, India, the Middle East, France and Great Britain gathered at Bristol and later at Toulouse in France to hear details of the progress which had been made with the Concorde supersonic airliner. This was the first time that representatives of the Concorde customer airlines had received this type of ‘on‐the‐spot’ technical presentation from British Aircraft Corporation, Sud‐Aviation, Bristol Siddeley Engines and S.N.E.C.M.A., and the whole venture has been described as highly successful. Not only did the customer airlines benefit from seeing, at the various plants, just exactly how the Concorde project is progressing, but they were also able to discuss in detail all engineering aspects of the aircraft with senior engineers of the Anglo‐French consortium. The manufacturers were also able to learn from the customers their views on particular aspects of the Concorde.

This paper is an overview of aero gas turbine engine starting systems and discusses the system design considerations and integration with other aircraft systems.

Review of a range of recent publications on the subject, aiming to provide an introduction to modern aero gas turbine engine starting systems.

Provides basic information on starter types and their limitations, and why some starter types are more favoured in modern installations. The effects of altitude and temperature are discussed which may not be initially considered as variables affecting aero start systems.

This paper provides further information on the starting systems of modern aero gas turbines and the considerations associated with integration and efficiency.

DOWTY ROTOL has recent experience in the design, manufacture and testing of two different electronically controlled wing trailing edge flap high lift actuation systems — one for the British Aerospace B.Ae.146 aircraft and the other for the Construcciones Aeronatuicas/Nurtania CN.235 aircraft. This paper discusses the application of electronics to control and monitor these systems. The resulting equipment is described and the two systems are compared for complexity, type of electronic architecture and reliability.

Developing and maintaining a pattern of sustainable livelihood (SL) is dependent upon the use to which we put our resources, particularly, our natural resources. SL is dependent upon five principal components; namely the vulnerability context, livelihood assets, transforming structures and processes, livelihood strategies and livelihood outcomes. DFID (1999), DFID, FAO, IFAD, UNDP, WFP (2001) liveli hood assets also have many components one of which is natural assets/capital. Once the environment is shocked the natural assets are directly affected and all other types of assets and principal components become inoperable. The livelihood outcomes of the Caribbean people, poor and otherwise, are therefore linked to these natural as sets. The objective of this study is to possibly shape and create ways of developing and maintaining patterns that can lead to SLs. It should focus on the available natural resources, access to and optimal use of, which can transit into the best livelihood outcomes specifically for the poor. Basically, the outcome should be a body of knowledge that can contribute to SLs within the Caribbean. This is done with the use of two case studies of Caribbean islands, namely St. Vincent and the Grenadines (SVG) and Grenada. This paper is divided into four sections. Section one provides the background for the paper and briefly introduces the concept of SL. Section two outlines the SL approach. Section three provides an application of the SL approach in SVG and Grenada from two varying standpoints. Section four makes concluding remarks on the types and the sustainability of the livelihood strategies and outcomes.

THE aerodynamic sessions of this year's Annual Meeting were not quite as dramatic as in some preceding years. But how can such sessions remain always at the highest pitch? Aeroplane designers have broken through the sonic barrier and aerodynamicists now understand far better compressibility effects and supersonics. One cannot expect every year a startling announcement of the kind that von Kármán used to make, that the drag coefficient would actually drop in supersonic flight, or that camber contributes nothing to lift at the highest speeds. This intellectual calm is only temporary. Rocket flight at a hundred miles altitude where molecules become individuals will bring tine new problems. So will the design of artifificial satellites. But for the time being, research men and engineers must present papers that dig deep but do not strike out into new territory. Also it is barely possible that there is another reason for the less exciting character of the aerodynamic papers—the word ‘Restricted’. For example, in one session it appeared that the fuel consumption of a jet‐propelled helicopter is still restricted information. To mark things ‘Re‐stricted’ or ‘Confidential’ can become a tiresome habit. However, there was no lack of the striking in other directions. What, for example, could be more intriguing than a session entitled Human Engineering in Aviation? Aeronautics is not all a matter of physics, mathematics, design and innumerable gadgets. It is more than fitting that psychologists, teachers, physicians should play their part and make the life of the pilot an easier one. Of course, the engineers do occasionally develop ‘gadgets’ that help the pilot, as witness the remarkable Sperry Zero Reader (discussed in the Instruments Session), and Air‐Borne Radar (Air Transport Session) that seems to be coming into its own.

A cowl for an air‐cooled aircraft engine comprising a series of rearwardly‐extending plate‐like flaps entirely separate from the cowl, a pair of rearwardly‐extending arms associated with each flap one at each margin thereof, a pair of longitudinal flanges on the side of each arm adjacent the flap so as to form a groove between them of which grooves at least one is of greater width than the thickness of the margin of the flap which can thus slide in at least one of said grooves, said margins being supported within said grooves, the circumferential distance between the flanges on one arm and the flanges on the other arm being substantially less than the corresponding dimension of the flap at all operating positions of the arms and the circumferential distance between the base of the groove on one arm and the base of the groove on the other arm being greater than the corresponding dimension of the flap, whereby the flap is supported solely by the arms at all operating positions thereof despite its being entirely separate from the cowl, a pivot for each arm lying along an axis at right‐angles to a fore‐and‐aft central plane, and driving mechanism carried by a fixed part of the cowl and operatively connected to each said arm to rotate it about said pivotal axis.

Conveys the author’s belief that the cataloging profession is uniquely suited to organize the wealth of information available on the World Wide Web. Focuses on the organization at which the author has worked for seven years (Central Technical Services, University Libraries, State University of New York at Buffalo), where she has capitalized on various OCLC‐inspired opportunities to explore Internet cataloging (i.e. InterCAT and CORC). A list of various procedures that this organization initiated to respond to and embrace Web resources is provided. Tries to impress upon the reader the importance of catalogers’ and bibliographers’ organizational skills when coupled with the progressive attitudes of library directors and staff. Key to ensuring the future success of bricks and mortar libraries and their employees is a committed response to patrons’ needs and the support of World Wide Web resources in the library catalog. Libraries must respond to the twenty‐first century paradigm shift in research methods.