An Easy Way to Analyze Longitudinal and Lateral-Directional Trim Problems with AEO or OEI

A user-friendly method for analyzing longitudinal and lateral-directional trim problems for airplanes with all engines operating (AEO) and with one engine inoperative (OEI) is presented. The method allows for rapid evaluation of various critical handling qiality parameters, such as stick-force per ‘g’ and stick-force versus speed gradients. In addtion, the effect of failures in trim systems on cockpit control forces and on control surface and/or tab deflections can be assessed. Also, the method can be used for sizing of tab control systems, down-springs, bob-weights and interconnect springs. Finally, elevator hingemoment derivatives for rather arbitrary aerodynamic balance configurations can be quickly estimated.