Flight dynamics models used in different national and international projects
Aircraft Engineering and Aerospace Technology
ISSN: 0002-2667
Article publication date: 29 April 2014
Abstract
Purpose
The present study aimed to demonstrate different computational models, data and stability results obtained in a wide number of projects of various aircrafts such as unmanned aerial vehicles (UAVs), general aviation and big passenger flying airliners in blended wing body (BWB) configurations. Many details of modeling and computing are shown for unconventional configurations, namely, for a BWB aircraft and for tailless UAVs.
Design/methodology/approach
Mathematical models for analysis of static and dynamic stability were built and investigated based on equations of motion in the linearized form using the so-called state variable model for a steady-state disturbed, generally asymmetric, flight.
Findings
Flight dynamics models and associated computational procedures appeared to be useful, both in a preliminary design phase and during the final assessment of the configuration at flight tests. It was also found that the difference between thresholds for static and dynamic stability conditions was equal to 9 per cent of mean aerodynamic chord (MAC) in the case of BWB and 3 per cent of MAC in the case of tailless UAVs.
Practical implications
Many useful information about aircraft dynamics can be easily obtained from computational analyses including time to half/double and periods of oscillation, undamped frequencies, damping ratio and many others. Stability analysis of different unconventional configurations will be easier and faster if an access to such configurations is available.
Originality/value
This paper presents a very efficient method of assessment of the designing parameters, especially in an early stage of the design process. In open literature, there are a great number of datasets for classical configurations, but it is hard to find anything for passenger BWB and tailless UAVs. Stability computations are performed based on equations of motion derived in the stability frame of the reference fixed with one-quarter of MAC. It can be considered as an original, not typical but a very practical approach because values of stability and control derivatives do not change even if the centre of gravity is travelling.
Keywords
Acknowledgements
The author would like to thank the European Commission (ESPOSA-Efficient Systems and Propulsion for Small Aircraft-FP7 project, contract 2011-284859) and Polish Ministry of Sciences and Higher Education for financial support.
Citation
Goraj, Z. (2014), "Flight dynamics models used in different national and international projects", Aircraft Engineering and Aerospace Technology, Vol. 86 No. 3, pp. 166-178. https://doi.org/10.1108/AEAT-02-2013-0036
Publisher
:Emerald Group Publishing Limited
Copyright © 2014, Emerald Group Publishing Limited