3503. Carefree Handling for Current Aerodynamically Instable Fighters — Resulting Requirements on Mass Properties as Well as In-Service Operation

Paper

Abstract

Modern fighters face high level mission requirements as well as complex combat scenarios. Additionally their agility has significantly grown, especially by the introduction of aerodynami- cally instable flight performance designs. This demands for solutions to reduce the pilots work- load in the field of aircraft flight control. It could be achieved by the application of a principle called Carefree Handling. This principle transfers the aircraft trim control together with the flight envelope limits observation to the aboard Flight Control System (FCS). Applying this, both tasks are completely and autono- mously performed by the FCS. The trim control is a permanent background process during flights. The flight envelop limit con- trol triggers FCS reactions at limit approach or exceedance. At limit approach the FCS poten- tially indicates warnings to the pilot(s). At limit exceedance the FCS initiates adequate counter measures. The risk potential at limit exceedance defines the safety requirements on accuracy and reliability of fundamental FCS input parameters. Basic technologies such as Fly-by-Wire and FCS architecture with powerful operating units are already available – hence Carefree Handling is technically feasible. The application of the Carefree Handling principle generates additional technological, logistical and operational effort. However it must be considered that for aerodynamically instable fighters the aircraft trim control must be performed by the FCS anywhere. In this paper basic aspects of the Carefree Handling principle with emphasis on their impact on mass properties handling are briefly outlined.