Maximum likelihood estimation of the longitudinal stability and control derivatives on a prototype business jet.

摘要

The results from flight tests are processed by parameter estimation programs to extract the stability and control derivatives for further analysis. A composite, twin engine jet aircraft with some unique design features such as forward swept wings and high, wing-mounted engines was tested and studied for this thesis. The specific method used to analyze the flight test data is known as maximum likelihood estimation. Maximum likelihood estimators have been developed and tested by NASA's Dryden Flight Research Center for nearly 30 years. The method requires accurate modeling of the dynamic system and basic inconsistencies such as noise approximations. The estimator can detect biases on the data and compensate for some measurement and process noise when necessary. Maximum likelihood estimation methods provide accurate information of the flying qualities and static and dynamic stability of an aircraft when used in this manner.