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IT is shown that the down gust requirement is open to the objection that heavier loads may be taken by the front spar at lightly loaded weight than those for which the spar was designed. This is normally covered by the factor of safety of 2, but the method of calculating the loads on a basis of all up weight is not very rational. Some available data concerning the magnitudes of down gusts are reviewed and the sharp‐edged gust hypothesis briefly examined. The British requirement is compared with those of the I.C.A.N. and the U.S.A. The conclusions are that there are no very practical alternatives to sharp edged theory and while the estimate of the magnitudes of normal down gusts at 25 f.p.s. appears satisfactory and British standards of strength in this respect need not be tightened up, a modification to the requirement to meet the above objection is desirable. A suggested alternative is put forward.

Extreme loads are generated in aircraft flight manoeuvres. Among different manoeuvres considered in this paper are motions following a sudden deflection of elevator and response to a vertical gust. Airplane was assumed to be a rigid body of three degrees of freedom in symmetrical motion. Elevator deflection was either of the step change type, or of the sinusoidal type, gust was assumed to be either of the step change type or harmonic, with a gust cycle time corresponding to the time to travel a distance equal to 25 Mean Aerodynamic Chord. In all cases a jump type elevator deflection was assumed to last for 1 second, whilst the airplane response was observed for 3 seconds. The airplane motion, its velocities, accelerations and load acting on the tailplane were calculated by means of numerical integration of the ordinary differential /of motion.

Temperature humidity acceleration factors for surface conductance are obtained to relate the reliability of film conductors formed by different processes. Analytical expressions for acceleration factor are evolved for both screen‐printed and laser micromachined conductor samples. The rapid solidification of metal conductors due to laser micromachining and its effect on surface conductance are also studied. An analytical expression for the most common accelerated test condition (85°C, 85% relative humidity) is also derived for both screen‐printed and laser micromachined samples.

A critical analysis of packaging and sealing methods for integrated circuits, hybrid microcircuits and multichip modules has been done. The best hermetic and high yield weld seal is examined along with other conventional seals like solder seal, frit seal and plastic seal with special emphasis on materials and processes involved in each case. An overview of emerging technology is also presented. A comparative analysis is made for selection of the right technology and material for a particular requirement.

In 1983 a group of nurses from the state of Colorado, US, convened to discuss the issues related to substance abuse among their colleagues. The absence of peer support for colleagues experiencing problems with addictions, and regulatory licensure sanction was of serious concern to them. They first determined that nurses themselves should provide services to nurses and students of nursing with substance abuse problems. After a review of the other state efforts, they concurred that the Employee Assistance Program (EAP) offered the comprehensive model of service delivery they envisioned. Originally incorporated in 1984 as NURSES (Nurses United for Recovery, Support and Education Successfully) of Colorado Corporation, this group also viewed the EAP as an important strategy to operationalise professional self‐regulation (Pace, 1990).This paper focuses on employee assistance programming, provided by nurses, as an effective workplace intervention strategy for the identification and referral to treatment of nurses affected by substance abuse and dependence.

This study aims to simulate gust effects on the aeroelastic behavior of a flexible aircraft. The dynamic response of the system for different discreet gust excitations is obtained using numerical simulations.

Coupled dynamics, including rigid and flexible body coordinates, are considered for modeling the dynamic behavior of the aircraft. Wing is considered flexible and other parts are considered rigid. Wing is modeled with nonlinear Euler Bernoulli beam. Moreover, unsteady aerodynamics based on the Wagner function are used for aerodynamic loading, and the results are compared with those of quasi-steady aerodynamics.

Von Kármán continuous gust is applied to this aircraft. In addition, the discrete “1- cosine” gust with different gust lengths is applied to the aircraft, and the maximum and minimum accelerations are computed. It is shown that the nonlinear modeling of the system represents the actual behavior and causes limit cycle oscillation phenomena.

This methodology can yield a relatively simple dynamic model for high aspect ratio aircrafts to provide insights into the vehicles’ dynamics, which can be available early in the design cycle.

Under this heading are published regularly abstracts of all Reports and Memoranda of the Aeronautical Research Committee, Reports and Technical Notes of the U.S. National Advisory Committee for Aeronautics, and publications of other similar research bodies as issued

THE Air Ministry has lately introduced extensive revisions into the official requirements for the strength of civil aeroplanes and the object of this article is to consider briefly their significance and effect on the trend of design. The general nature of the problem and the development and character of the system which is being modified must, however, first be summarised if the real meaning of these changes is to be appreciated. The problem of fixing the requisite strength for a given aeroplane divides naturally into two parts; first the magnitude of external loads which the aeroplane must be assumed to encounter, second the structural problem of determining the methods to be used in ascertaining the resistance to those actions.

Under this heading are published regularly abstracts of all Reports and Memoranda of the Aeronautical Research Committee, Reports and Technical Notes of the U.S. National Advisory Committee for Aeronautics, and publications of other similar research bodies as issued

A laser ablation technique has been used to fabricate conductor patterns on a 96% alumina substrate to evolve passive fine‐line components and structures. This paper reports the method of fabricating better fine‐line passive components for hybrid microelectronics application. The effect of a laser beam on the conductor and 96% alumina (Al₂O₃) substrate was studied in detail. Three predominant structures — namely debris, ablation border and irradiated bottom layer — were seen on the patterns. A detailed study of the dendritic growth caused by electrochemical migration on conductor lines fabricated by conventional screen printing and by laser ablation techniques is also reported.