Flight Dynamic Investigations of a Blended Wing Body Aircraft
Autor: Christoph Neubacher
Project
Abstract
This thesis deals with stability investigations and a motion simulation of a non conventional
aircraft configuration. The investigated aircraft of this thesis is called AC 20.30
and is a Blended Wing Body model aircraft, which was designed by a research group
of students of the University of Applied Science Hamburg. The stability investigations
of the AC 20.30 should show, if the aircraft is statically and dynamically stable for the
longitudinal and lateral motion. The aircraft stability can be computed with the help
of the stability derivatives computed with the aerodynamic coefficients measured in the
Wind tunnel Dresden. As a result of the stability investigation, the AC 20.30 shows for
two characteristics motion modes of the longitudinal motion, the Phugoid mode and the
Short Period mode, dynamically stable behaviour. The stability investigation for the
lateral motion results in dynamically stable flight characteristics for the Roll and Dutch
Roll mode, while the AC 20.30 is dynamically unstable for the Spiral mode. Additional
to the stability investigation the AC 20.30 is investigated for its flight characteristic
and is classified into flight levels. The AC 20.30 shows for the longitudinal motion
level 1 flight characteristics, while the flight characteristics for the lateral motion are
between level 1 and 2. The motion simulation of the AC 20.30 takes place in the Matlab
Simulink environment. It should simulate, how the AC 20.30 acts in its different motion
directions, if the control surfaces are deflected or if suddenly appearing gusts affect the
aircraft. The simulation should also show, whether or not the aircraft is able to damp
out the mentioned disturbances in the motion directions.