Robust maneuvering envelope estimation based on reachability analysis in an optimal control formulation
This paper discusses an algorithm for estimating the safe maneuvering envelope of damaged aircraft. The algorithm performs a robust reachability analysis through an optimal control formulation while making use of time scale separation and taking into account uncertainties in the aerodynamic derivatives. Starting with an optimal control formulation, the optimization problem can be rewritten as a Hamilton-Jacobi-Bellman equation. This equation can be solved by level set methods. This approach has been applied on an aircraft example involving structural airframe damage. Monte Carlo validation tests have confirmed that this approach is successful in estimating the safe maneuvering envelope for damaged aircraft.
Aviate, Navigate: Functional Visualizations of Asymmetric Flight Envelope Limits Supporting Pilot Decision Making in Failure Scenarios
Current aircraft flight deck interfaces do not provide information on how a performance-altering failure constrains the aircraft’s flight envelope. As a result, it is difficult for flight crews to plan an emergency landing trajectory. This study presents the results of the conceptual development of novel constraint-based interface symbology that aims to solve this issue. As no fully functional on-line flight envelope prediction system implementations currently exist, a simplified dynamical model with an asymmetric flight envelope was developed to overcome this limitation. The proposed interface symbology integrates with the existing primary flight display and navigation display. A human-in-the-loop experiment was conducted to validate the effectiveness of the used symbology. The results lend credibility to the belief that presenting flight envelope constraints in terms of reachable navigation states may improve short-term tactical planning and reduce the pilot’s mental workload during emergency situations.
LHC Design Report Vol.1: The LHC Main Ring
The LHC Design Report is presented in three volumes: the first concerns the main ring, the second the infrastructure and general services and the third, the injector chain. The conceptual design was published in 1995 and this report provides a snapshot of the detailed design as it stands at the time of writing - early 2004