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The purpose of this paper is to evaluate the accuracy of linear and quasi-steady aerodynamic models of aircraft aerodynamic models when a small unmanned aerial system flies in the presence of strong wind and gust at a high angle of attack and a high sideslip angle.

Compatibility analysis were done to improve the quality of recorded flight test data. A robust method called fuzzy logic modeling is used to set up the aerodynamic models. The reduced frequency is used to represent the unsteadiness of the flow field according to Theodorsen’s theory. The work done by the aerodynamic moments on the motions is used as the criteria of stability.

In portions of flight, aircraft’s stability and control derivatives were unstable and nonlinear functions of airflow angles and angular rates. The roll angle had an important effect on unsteadiness of directional oscillatory damping derivatives. The pilot-induced oscillation and wing rock possibilities were investigated and dismissed so that the lateral directional oscillatory motion was classified as a nonlinear Dutch roll oscillation. Major modeling enhancements or real-time parameter identification are required for the control of a small unmanned aerial system in off-nominal conditions. The robustness tests of all-weather autopilot systems must be done with consideration of sign change.

Oscillatory damping derivatives were reconstructed using flight test data and the inadequacy of engineering level software in predicting this type of instability observed and demonstrated for a flight in the presence of wind shear and external disturbances.

AN ESTEEMED correspondent points out that there are about two dozen library magazines of all sorts and sizes in circulation, whereas when he started his career there were no more than three. Our correspondent has himself had considerable editorial experience, and it may be that he is still in harness in that regard. One of his earliest efforts was in running the magazine of the old Library Assistants' Association, and it is not likely that that magazine has ever reached the same heights of excellence as it attained in his day. He observes that there are far too many library magazines now in circulation. We agree.

British retailers may be slightly envious to read that their American counter‐parts expect “a good but not spectacular year” in 1977, and that over the next ten years retail sales and profits will double. This at any rate is the view of Edward W. Carter, chairman of Carter Hawley Hale and a respected authority on the US retail scene. This is a summary of a talk he gave at the Association of Buying Offices luncheon in New York recently, timed to coincide with the National Retail Merchants' Association annual convention, which was also held in New York.

Purpose: The purpose of this study is to analyze the changes organizations can adopt to move beyond budgeting. We show how these changes can be understood as modes of adaptive performance management that explains the ways in which organizations move beyond budgeting to become more adaptive. The proposed modes are then used to derive propositions for future research.

Methodology/approach: We follow a conceptual approach through an analysis of the beyond budgeting principles using the management and systems literatures on radical decentralization. We theorize how organizations can enhance their adaptability to environmental uncertainty through changes to their management structure and control processes.

Findings: We show that organizations can move beyond budgeting by decentralizing within or beyond their management structure and modifying or removing their budget-based control processes. We propose that beyond budgeting can be conceptualized as four modes of adaptive performance management: better budgeting, advanced budgeting, restricted budgeting, and nonbudgeting.

Research limitations/implications: The four modes of adaptive performance management can be used in future research to consider how changes to management structures and budget-based control processes can enhance the organizational adaptability needed to manage environmental uncertainty.

Practical implications: We show that while the nonbudgeting mode may be most suited to organizations facing high levels of environmental uncertainty, organizations facing low–to-moderate levels of environmental uncertainty can achieve sufficient levels of adaptability with less extensive changes to management structure and budget-based control processes.

Originality/value: The four modes of adaptive performance management reflect different approaches for dealing with environmental uncertainty. Positioning nonbudgeting as one mode and identifying alternate modes of adaptive performance management provides a basis for comparing and understanding the changes organizations make to move beyond budgeting.

The following definitions and standards for food products have been adopted as a guide for the officials of this Department in enforcing the Food and Drugs Act. These are standards of identity and are not to be confused with standards of quality or grade; they are so framed as to exclude substances not mentioned in the definition and in each instance imply that the product is clean and sound. These definitions and standards include those published in S. R. A., F. D. 2, revision 4, and those adopted October 28, 1936.