Worst case gust shapes for atmospheric turbulence with known spectrum

A worst case gust shape has been derived for turbulence or gust patches, assuming only that the average spectrum of such patches is known. The maximum value of the response can be calculated quite easily. The result differs from the PSD-method. Some examples of worst case inputs and outputs are given, also for nonlinear systems.

Estimation of load exceedances of an aircraft undercarriage with nonlinear properties excitated by random runway unevenness

In this report various methods to describe a landing gear with nonlinear properties and excitated by random runway unevenness during taxying have been investigated. The results of calculations have been compared to measured results from an analog computer simulation. The mean behaviour, standard deviations and power spectra, can be described...

Historical development of collision risk models for en-route air traffic

This lecture reviews the model studies that were made with the object to reduce en-route separation standards. It also describes the basic principles of the Reich model used in most of these studies and of the Minimum Navigation Performance Specification (MNPS). Paper presented at the Princeton University Conference 155, "Safety Issues in Air...

Digital filtering methods, with applications to satellite attitude determination in the presence of modelling errors. Part I: theory

The report reviews a number of digital filtering methods and gives examples of their application. The methods include batch processing methods and rec\irsive methods, not only in the classical formulations but also in square-root formulations. The latter formulations have the purpose to prevent certain numerical inconveniences. Much attention is...