2462. Effect of Control Surface Balance on Flutter

Paper

Abstract

Mass properties’ engineers often are concentrating on creating and maintaining the most accurate and current weight database possible on our aircraft or system. They tend to lose sight of why accurate weight data is important. While having accurate weight data is intrinsically valuable, it can have a major impact on design decisions and even on the viability of a design. Some systems are more sensitive to changes in weight and center of gravity than others. One of the critical elements in the design of aircraft is ‘flutter modes’. Every moving body has vibration frequencies. It is important to avoid coupling frequency modes in the airplane components. This can have catastrophic results, including loss of property and lives. Excessive vibration can result in metal fatigue, even without catastrophic failure. It is important that accurate weight and balance data be available to design engineers early in a program. Many problems can be avoided if a potential flutter situation is identified early in a program. An important way the mass properties’ engineer can assist in preventing flutter is by working closely with loads and flutter engineers to optimize the control surface balance. Parametric studies are run by loads and flutter engineers to determine the optimal balance weight and location to achieve no coupling of vibration modes. The mass properties’ engineer needs to assure that the mass properties’ data provided for future analyses reflects this optimal value and the system balance about its hinge line is within the limits established.