Evaluation of a Sliding Mode Fault-Tolerant Controller for the El Al Incident

Abstract

This paper presents piloted flight simulator results associated with the EL-AL flight 1862 scenario using a model reference-based sliding mode control allocation scheme for fault tolerant control. The proposed controller design was carried out without any knowledge of the type of failure, and in the absence of any fault detection and isolation strategy. This is motivated by the fact that the flight crew were unaware of the loss of the right engines. For this reason, the control allocation scheme which is proposed uses (fixed) equal distribution of the control signals to all actuators (for both nominal situations and when a fault or failure occurs). The paper analyzes the scheme and determines the conditions under which closed-loop stability is retained. The results represent the successful real-time implementation of the proposed controller on the SIMONA motion flight simulator configured to represent a B747 aircraft. The evaluation results from the experienced pilots show that the proposed controller has the ability to position the aircraft for landing in both a nominal and the EL-AL failure scenario. It is also shown that actuator faults and failures which occured during the EL-AL incident can be handled directly without reconfiguring the controller.

Hybrid Sensor-Based Backstepping Control Approach with Its Application to Fault-Tolerant Flight Control

“…Edwards et al [4], which enables the results in this paper to be compared to the results presented in [4,5]. It should be noted that the altitude tracking control task would be switched into flight path angle command tracking mode at the 650 th second in order to mimic a landing process with fixed gliding slope (i.e.γ = −3 deg).…”

“…To simplify the control allocation logic, some of the aircraft inputs can be combined and the following 19 equivalent control variables can be used instead [4,14,21]:…”

“…A number of FDI methods, as well as reconfiguring control approaches, have been proposed in the literature [4,[6][7][8][9][10]. More recently, the work of Lombaerts et al [5], as a part of the GARTEUR FM-AG 16 program, has provided practical validation results of a piloted adaptive nonlinear dynamic inversion (ANDI) controller on the Simulation, Motion, and Navigation (SIMONA) research simulator (SRS).…”

“…The ANDI rate controller guarantees the stability of the postfailure aircraft and enables the pilot to land the aircraft safely. Thereafter, Alwi and Edwards et al [4] validated another type of reconfigurable control method on the SRS, which was designed using a model reference sliding mode control method together with a constant control allocation matrix.…”

Sliding mode methods for fault detection and fault tolerant control with application to aerospace systems

“…The idea is only to trigger the adaptive scheme if a fault is present and a degradation in the sliding motion begins to appear (Alwi et al, 2010). give a view of a virtual environment and a motion system moves the entire cabin to simulate aircraft motion.…”