Fixed Wing Design
Stability and Control from the Very Beginning
When developing an aircraft from the beginning, the process of flight dynamics, stability and control, and flight physics analysis are often left until the design has started to become fixed before this work is performed. One of the main reasons for this was that the process of developing a model, developing the code or block diagrams and all the mathematics involved was a lengthy process. This meant it was not viable to perform this work for every concept and idea being investigated. Now, with the j2 Universal Tool-Kit, this is no longer the case, flight dynamics and simulation can start from the very beginning of a project providing the ability to investigate stability and control matters as well as pilot in the loop simulations instantly. As the aircraft design evolves so the data is updated and a new set of results generated. Everything is tracked and traced with integrated version control.
The hierarchical structure for developing the models that is present in j2 Builder enables the aircraft and proposed systems to be laid out in the model as in the real aircraft. As the aircraft evolves so whole sub-assemblies can be relocated quickly and easily and the software will take care of all changes in locations and moment arms to recalculate contributions. With limited information relating to airfoil type, wing geometry and location, the complete aircraft model can be developed in j2 Elements. This provides detailed dynamic characteristics based upon the local flow at any point on the wing. Legacy tools and existing data frameworks can easily be added into the j2 model framework using j2 Developer.
Stability through to Certification Analysis
Models can be put through any form of analysis ranging from Dynamic Response Modelling in j2 Freedom to Linear Stability and Control Assessment in j2 Classical. Manoeuvres can be created to cover basic disturbances and pilot inputs such as doublets and 3211’s or more complex Certification flight profiles. In this way it is possible to evaluate whether the aircraft is able to be Certificated and if not, what changes are needed to ensure complete compliance.
j2 Pilot offers the ability to take any aircraft developed within the j2 Universal Tool-Kit and test it in a Pilot-in-the-Loop real time simulator. From the very beginning of the design pilot opinions can be gathered and used to shape and evolve the design. The models can be updated instantly and re-flown. As the design heads towards Certification so the simulator can be updated and, with the j2 Pilot SDK, can be integrated with level D fidelity hardware for Pilot Training.
Flight Test and Envelope Expansion
When the aircraft is ready for flight, so the j2 Universal Tool-Kit still supports the development process. Flight Test programs are developed using j2 Freedom to plan the best way to demonstrate the aircraft’s capabilities and to validate the predictive model. The test flights can be rehearsed and refined through pilot evaluation on the j2 Pilot Simulator. Once the flight has been performed, the j2 Flight component provides the ability to take the data and to clean it up through flight path reconstruction. The automatic flight matching capability provides an integrated approach to refining the model ready for the next set of test points and further expansion of the aircraft’s capabilities.