NLR Contributions to the flutter certification of aircraft with external stores

An outline is given of store flutter clearance activities of the NLR carried out by order of the Royal Netherlands Air Force. Special attention is devoted to the store flutter clearance of the F16 aircraft. Presented at: 7th Aircraft/Stores Compatibility Symposium,Wright-Patterson AFB, Ohio, 8-10 April 1986 and at the 17th Annual Symposium of...

Dynamics of flexible spacecraft: an analysis approaches towards mathematical model order reduction

Increases in size and mechanical complexity of spacecraft result in increased complexity of the mathematical model which describes the spacecraft dynamics. This results in turn in increased computational effort, in increased difficulties in understanding the characteristics of the spacecraft dynamics, and in increased difficulties in the design...

Methoden voor het verbeteren van dynamische modellen van constructies

A survey of computational methods to improve dynamic analytical models described in the literature is made. Both the matrix methods and the optimal correction method of the dynamic model using the measured modes are discussed.

Three-dimensional flight-path reconstruction by means of spline approximation

In NLR TR 82075 U, a method has been developed to reconstruct the flight-path of a symmetric flight, by representing this path by a set of splines. In the present report, the same method is being applied to a three-dimensional flight over a rotating earth. Preliminary results are comparable in accuracy and computing time to the Kalman (Square...

Parameter identification results of tests in non-steady symmetric flight with the Hawker Hunter Mk VII

This report presents the parameter identification results derived from data recorded during non-steady symmetric flight test manoeuvres with the Hawker Hunter Mk VII laboratory aircraft. This flight test program was executed in co-operation with the Department of Aerospace Engineering of the Delft University of Technology. The reproducibility of...

Two-dimensional flight-path reconstruction by means of spline approximation

In this report, a method is developed to reconstruct the flight-path of an aircraft in symmetric, non-steady flight by representing this path by a set of splines. That set of splines is chosen, for which the flighttest data are best explained in some weighted least squares sense. This leads to a large, sparse, nonlinear, overdetermined system,...

Het meten van lichtreflecties van gewassen

Measurement of an object's reflectance spectrum can provide information on its nature and qualities. However, one should thoroughly take into account the fact that in general the reflectance spectrum does not only depend on the object itself, but also on the parameters defining the measurement conditions, like the spectral and spatial...

Non-destructieve bepaling van gewaseigenschappen met behulp van multispectrale scanning

The spectral distribution of radiation reflected by crops in the visible light region and the near infrared contains information concerning crop structure and the optical properties of the leaves and the bounding soil. Non-destructive determination on remote distance of crop properties by means of the measured spectral distribution of reflected...