Carrier-based Aircraft Approach The Dynamic Compensation And Automatic Throttle Control System Design

Taking off and landing are the most important and difficult issues considered for fixed-wing carrier aircraft. Aimed at the strong need for improving carrier landing, the Automatic Carrier Landing System (ACLS) has been applied to approach guidance and path control for decades. As an important component of the ACLS, the Approach Power Compensator System (APCS) has a purpose of relieving the pilot of the throttle management task during all phases of carrier approach. By imposing the compensation control laws on the Automatic Throttle Control System (ATCS), the APCS is normally required to manage the engine power so as to keep flight stable and improve the flight path control. Aiming at an engineering application, some studies on the APCS and the ATCS are presented, and briefly listed below.Different APCS structures and the effects on flight path response are presented. Basing on small disturbance dynamic equations of aircraft moving within a vertical plane, without consideration of the air-wake, the elevator deflection and the short term process of moment balancing, a simplified control model of the flight path angleγresponse to pitch angleθwith APCS is presented. A normal transfer function of the simplified model is deduced, with which the effects of the APCS on flight path response can be easily analyzed. Simulations and validations of theγresponses toθwith four different compensation modes are presented. The four compensation modes are (a) without APCS, (b) with the speed regulator APCS|u, (c) with the angle of attack regulator APCS|αand (d) with APCS|α+nz fed back with both the angle of attackαand the normal acceleration nz respectively. The results indicate that the flight path response can be improved to be stable, rapid and accurate with the APCS|α+nz compensation structure.An engineering APCS, including its compensation structure, control laws and the throttle command algorithm are presented. Aimming at the actual requirements of the engineering application, a compensation structure of APCS|α+nz+δe is defined, where the angle of attackαand the normal acceleration nz and the elevator variationδe are all fed back. Basing on the structure, the system parameters are calculated, and the flight path response is simulated for system validation. The results support a conclusion that the APCS presented matchs the actual requirements well.An improved mechanical and electrical bi-operating ATCS is also presented in this paper. In auto mode of the ATCS, the APCS manages the throttle automatically according to the flight conditions and the control laws.The system principle, control logic, main components are presented briefly. In particularly, the automatic throttle servo device is further introduced.System validating tests for the improved ATCS, including separate component performances and integrated system performances, are presented. The performances of the moment switch, the throttle handling device, the throttle servo device, and the wire-wheel assembly are concerned separately. For integrated system performances, the throttle responses to step signal, sine wave singnal and random signal, and the performances of modes switching are tested and validated. The results indicate that the ATCS is feasible for the APCS applications.