Static internal performance of an axisymmetric nozzle with multiaxis thrust-vectoring capability

An investigation was conducted in the static test facility of the Langley 16 Foot Transonic Tunnel in order to determine the internal performance characteristics of a multiaxis thrust vectoring axisymmetric nozzle. Thrust vectoring for this nozzle was achieved by deflection of only the divergent section of this nozzle. The effects of nozzle power setting and divergent flap length were studied at nozzle deflection angles of 0 to 30 at nozzle pressure ratios up to 8.0

Effects of empennage surface location on aerodynamic characteristics of a twin-engine afterbody model with nonaxisymmetric nozzles

An investigation has been conducted in the Langley 16-Foot Transonic Tunnel to determine the effects of empennage surface location and vertical tail cant angle on the aft-end aerodynamic characteristics of a twin-engine fighter-type configuration. The configuration featured two-dimensional convergent-divergent nozzles and twin-vertical tails. The investigation was conducted with different empennage locations that included two horizontal and three vertical tail positions. Vertical tail cant angle was varied from -10 deg to 20 deg for one selected configuration. Tests were conducted at Mach number 0.60 to 1.20 and at angles of attack -3 to 9 deg. Nozzle pressure ratio was varied from jet off to approximately 9, depending upon Mach number. Tail interference effects were present throughout the range of Mach numbers tested and found to be either favorable or adverse, depending upon test condition and model configuration. At a Mach number of 0.90, adverse interference effects accounted for a significant percentage of total aft-end drag. Interference effects on the nozzle were generally favorable but became adverse as the horizontal tails were moved from a mid to an aft position. The configuration with nonaxisymmetric nozzles had lower total aft-end drag with tails-off than a similar configuration with axisymmetric nozzles at Mach numbers of 0.60 and 0.90

The Fishery Conservation and Management Act of 1976: Management Objectives and the Distribution of Benefits and Costs

The purpose of this article is to raise some questions concerning the appropriate objectives for fishery management. Management objectives are evaluated by examining the implications of different policies regarding the distribution of benefits and costs among the many and varied interests involved. Part I of the article begins with a discussion of the failure of the Act and its legislative history to provide satisfactory objectives. Part II identifies some of the interests related to the use of fishery resources, and Part III examines the likely effects on these interests of policy choices in three issue areas—the adoption of entry limits (including the technique of user taxes or fees), the investment of public funds, and the allocation of yields. In the process, an attempt to illustrate the importance of clearly defining management objectives is made

Preface

Non

Fisheries and the New Conventions on the Law of the Sea

In spite of the economic and political importance, fishery problems are being dragged in by the back door, to face decisions by diplomats who, for the most part, lack the requisite interest and competence to solve such problems. It is because of this that it seems timely and useful to raise a few points that might be considered by those who are (presumably) preparing themselves for the new conferences on the law of the sea. (1) The problems of fisheries, because of both the centuries of use and the recent, dramatic changes in enterprise, are inordinately complex. However, the issues have not been precisely described and the alternative resolutions have scarcely been formulated. (2) The over-emphasis on the seabed may lead to short term gains for those related interests at the cost of long term damages to the world\u27s interests in fisheries. (3) The character of today\u27s decisionmaking arena is far different from that of 1958. The fishery diplomats will not be participating in a club of fishing states, but in the context of a global interest in the wealth of the seas, and in the fears of a United States-Soviet Union condominium. (4) there is increasing awareness that the patterns of distribution among nations of the sea\u27s wealth in fisheries is becoming more and more non-inclusive in nature, and that the opportunities for sharing are more restricted. (5) These non-inclusive patterns of distribution are supported by customary and conventional law. Non-inclusive access to (though not distribution of) wealth is required for efficiency in production. If there is to be more inclusive sharing of wealth, then there is need for totally new institutions of law