The Role of Error in the Conceptual Design of a Transport Aircraft

A fidelity trade environment was demonstrated by using it to simulate a decision making process for a transport aircraft. This scenario was not possible without the fidelity trade environment. The role of system feedback and coupling in error stability was also investigated. A sensitivity approach which relies on the system sensitivity matrix was used to rapidly approximate the propagation of error through the complex system. In verification tests, the sensitivity approach provided approximate results substantially similar to a Monte Carlo approach that was many orders of magnitude more expensive. The rapid sensitivity approach to modeling error propagation enabled the responsive analysis required for an interactive environment. A notional transport aircraft was modeled in the fidelity trade environment. The system was decomposed and the fidelity trade environment was used to integrate the system. Then, a scenario was described where a decision maker used the fidelity trade environment at the beginning of a complex systems design problem. Using the environment, the designer was able to make design decisions while considering error and he was able to make decisions regarding required tool fidelity as the design problem continues. These decisions could not be made in a quantitative manner before the fidelity trade environment was developed. The role of system feedback and coupling in the growth or decay of an individual error source was investigated. The diagonal entry of the inverse system sensitivity matrix was identified as the determining factor in the stability of a particular error source.