Flapping wing systems are being developed by various institutions and research groups around the world with many systems developed that are capable of full flight. However, while instrumentation has been developed that is capable of measuring some of the characteristics of these systems, there is no complete solution. This paper seeks to take the first step toward instrumentation that could be applied to any flapping wing system. This first step is to identify and characterize the forces that are operating on flapping wing systems. This paper presents, in premiere, a systematic analysis of all cases that can create useful or parasitic aerodynamic loads along with the other major loads that would be experienced by these cases and methodology for how these can be measured with the ambition that it can become a framework to be used to characterize any flapping wing system.