Programme and real-time operations simulation support tool prosim

The Programme and Real-time Operations SIMulation support tool PROSIM is a generic simulation tool that can be used for design, verification, test and training of a wide range of applications, such as aircraft and groimd vehicles. PROSIM originated as part of the National Simulation Facility NSF at the Dutch National Aerospace Laboratoiy NLR, a...

WISPER and WISPERX Final definition of two standardised fatigue loading sequences for wind turbine blades

WISPER and WISPERX are standardised variable-amplitude test loading histories for use in the fatigue design of horizontal axis wind turbine blades. They are based on flap load service measurements on 9 different horizontal axis wind turbines, covering a wide range of materials, rotor diameters and geographical locations. The present report is...

Standardized environmental fatigue sequence for the evaluation of composite components in combat aircraft (ENSTAFF = ENvironmental FalSTAFF)

Fatigue life assessment of composite structures in fighter aircraft necessitates testing with both mechanical and environmental loading at both coupon and structural element size levels. Testing facilities to run such tests are now available but environmental fatigue testing is expensive and time consuming. An environmental fatigue loading...

European approaches in standard spectrum development

Typical characteristics of various types of service loading are presented as they were discussed during the establishment of standardised test load sequences. Counting methods are reviewed and a simple and powerful algorithm is given to perform rainflow counting and to store the counting results afterwards. Synthesis procedures are discussed...

Fatigue Rated Fastener Systems: an AGARD coordinated testing programme

The report contains the description, results and conclusions of a fatigue test programme which assessed the fatigue lives of fastener systems using different joints. High load transfer single shear joints were evaluated in a core programme; secondary bending and load transfer were determined experimentally. About 750 specimens were fatigue...

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...

De invloed van CAD op research

NLR has developed an infrastructure of hardware and software for support of aerodynamic design of aircraft. Organizational and technical aspects of this development are described.

Comparison of a jump-diffusion tracker with a Kalman tracker: an evaluation with emphasis on air traffic control

A sophisticated starting point for a probabilistic approach to the radar tracking problem is a Markov jump-diffusion model for the aircraft dynamics, its control and the radar measurements. From nonlinear filtering theory, a closed form description of the evolution of the conditional distribution of this Markov process can be obtained. This jump...

Trends in airline avionics

Modern avionics are an integral part of the aircraft. They provide the functions of communication, navigation, energy management, identification, weather, terrain, and collision avoidance, the presentation of flight and warning data as well as aircraft guidance and stabilization. New developments in micro-electronics and display technology...

The use of standardized fatigue load sequences in coupon and component tests

Due to the development of servo hydraulic fatigue testing machines, fatigue tests under realistic loading conditions have become possible. In these tests, standardized load sequences can be applied. The paper describes the main properties of such sequences, including TWIST and FALSTAFF. Various examples of application of these sequences are...

Digital filtering methods, with applications to spacecraft attitude determination in the presence of modelling errors. Part II: Extension of theory, and applications

The present issue is the second and final part of a report describing the results of a study about digital filtering. The first part is available as the report NLR TR 760U8 U. The report considers a number of digital filtering methods and gives examples of their application. The methods include batch processing methods and recursive methods....

The estahlishment of safe separations between aircraft in flight

The paper starts with a review of the history of the use of models and statistical data for the assessment of separation standards. This work was mainly done by the ICAO Vertical Separation Panel, the North Atlantic Systems Planning Group and the ICAO Panel for the Review of the General Concept of Separation. After a brief description of the...