THE EFFECT OF ADDITIONAL 10% PLATE TO THE RUDDER OF AN N2XX AIRCRAFT ON THE HINGE MOMENT BASED ON THE COMPUTATIONAL FLUID DYNAMICS METHOD

Abstract

The N2XX aircraft developed by PT. Dirgantara Indonesia (Persero) is an aircraft equipped with a full mechanical control system designed to support flight operations in remote and pioneer routes. The rudder plays an important role in maintaining yaw stability and providing maneuverability during critical conditions such as takeoff, landing, and asymmetric thrust situations. When the pilot inputs a yaw command, a counter force is generated on the control surface known as the hinge moment. The magnitude of the hinge moment influences pilot handling comfort as well as flight safety. This study aims to compare the hinge moment characteristics between the basic rudder configuration and a rudder with a 10% area modification using an additional plate. The analysis was conducted using the Computational Fluid Dynamics (CFD) to evaluate the pressure distribution and aerodynamic forces acting on the rudder. Simulations were performed with rudder deflection variations of −20°, 0°, and 20°, and sideslip angle (β) variations of −10°, −5°, 0°, 5°, and 10°. The simulation results indicate that increasing the rudder area by 10% using an additional plate increases the hinge moment by approximately 15% compared to the basic rudder configuration due to changes in pressure distribution and vortex formation on the rudder surface.