To control an un-swept flying wing is problematic in some ways. One of the problems is that when the wing experiences a disturbance in yaw, it does not, since it has no tail, generate any torque in the opposite direction as a plane with a vertical stabilizer does. This thesis is foremost aimed at exploring one particular solution to this problem.
One approach to this problem is to place the motors out on the wing and differentiate the thrust, to achieve the same torque as splitted elevons or a vertical stabilizer does. This is what NASA used on the flying unmanned wing HELIOS. Reducing the thrust on the right set of engines, and increasing the thrust on the left side can mean that the combined thrust is unchanged. And thus more fuel efficient, and increases endurance.
This project’s main goal has been to construct a half scale model of the school project flying wing Solaris, and to configure a control system for the differentiated thrust as used on Helios. Thereafter conduct flight testing and evaluate the controllability of the wing in a number of flight conditions, this to get a sense of the wings characteristics and which parameters one should adjust to get the best controllability as possible.
After numerous adjustments and test flights it was concluded that it is possible to construct and fly a wing in this configuration, with relatively simple means, with satisfactory results.
That the torsional rigidity has great influence on the controllability were evident after the test flights. After redistribution of the components on the wing the conclusion could be made that the dihedral could be held within the structural limit of the wing.
The results of this thesis will contribute to the project Solaris at Mälardalens University in Västerås, Sweden. The project was carried out at Mälardalens University. The test flights were conducted at the former Air Force base F-15 Flygstaden and Mohed in Söderhamn, Hälsingland.
2011. , 32 p.