Envelope Protection and Atmospheric Disturbances in
Icing Encounters
Jason Merret, Kishwar N. Hossain, and Michael B. Bragg
University of Illinois, Urbana, Illinois, 61801
ABSTRACT
Research is reported on aircraft performance and control
in icing, related to the development of Smart Icing Systems
for improved flight safety. Microburst and gravity wave atmospheric
disturbances were modeled, and their effects on the aircraft performance
and control were compared to that of an icing encounter. Simulations
were run using a six degree-of-freedom computational flight dynamics model.
The study showed that microbursts could easily be differentiated from icing
encounters. On the other hand gravity waves are more difficult to
differentiate. A plan was formulated for developing an envelope protection system effective in icing conditions. Two dimensional airfoil data
were analyzed and showed promising results for prediction of envelope limit
exceedence. Changes in unsteady hinge moments were especially effective
in predicting stall.