In the world of aviation, ensuring efficient and safe flights is of utmost importance. To achieve this, an applied science known as Flight Mechanics is required. It focuses on the study of aircraft motion as they travel through the air. In this context, flight control systems play an essential role by enabling aircraft response to be controlled and adjusted under different flight situations and conditions.
What Is Flight Mechanics?
Flight Mechanics is the applied science that studies the motion of aircraft as they travel through the air, primarily applying knowledge of Classical Mechanics, Aerodynamics, and Propulsion to determine flight trajectories and conduct stability studies. These analyses make it possible to develop designs that meet customer specifications while also complying with the certification requirements established by aviation authorities.
What Are Flight Simulators?
Among the tools most commonly used by engineers working in this field are flight simulators. These are real-time computing platforms that, depending on their level of complexity, integrate physical and mathematical models to represent aircraft systems and components, the interfaces between them, physical environments, and, in general, models capable of determining aircraft behavior.
Due to the large number of models exchanging information with one another, the so-called integration process is critical. This process basically consists of connecting all the models together to generate a new application or standard.
Integration of Flight Control Systems
At SII Group Spain, we collaborate with SII Toulouse on the integration of flight control systems, computers capable of controlling an aircraft’s response, from a Flight Mechanics perspective, when an input signal is applied to the aircraft (referred to in control theory as the plant). These systems fall into two major categories: stability augmentation systems and autopilots. The former modify the aircraft’s natural characteristics (natural frequency, damping, response times, etc.), while the latter are feedback-based algorithms (closed-loop systems) designed to satisfy the control laws established by the pilot.
Regarding the integration of control systems, the process begins with receiving a new version of the control algorithm model from the design team. This team is responsible for developing new algorithms or correcting errors found in previous design iterations. Once the new iteration (known as the specification) is received, its format is adapted, and the new input and output ports that must be connected between the different models are identified. To understand the concept of port connection, each model is treated as a black box, since the focus is solely on identifying and understanding the interfaces between models. The design office is responsible for the internal implementation of each model, while the integration team manages the interfaces.
The modifications introduced by the designers compared to the previous specification—that is, the one used as the basis for the new version—generally involve adding information to be transmitted between models or removing transmission channels. Once this port connection process is completed, tests are carried out on the newly integrated application within the simulation platform. These basic functional tests verify that the main connections have been implemented correctly and that the integrated application operates as expected.
Once validated, the application is delivered to the validation team, which performs more comprehensive and in-depth testing on the same simulation platform to thoroughly assess the behavior of the new models delivered by the design team. Any issues identified may be due to either design or integration errors. In either case, a report must be issued describing the detected issue, the affected systems, and the expected behavior to facilitate problem resolution by the team receiving the application back, whether it is the design team or the integration team.
