A comprehensive series of experiments and analyses was performed on co
mpressor and turbine blading to evaluate the ability of current, pract
ical, engineering/analysis models to predict unsteady aerodynamic load
ing of modern gas turbine blading. This is part of an ongoing effort t
o improve methods for preventing blading failure. The experiments were
conducted in low-speed research facilities capable of simulating the
relevant aerodynamic features of turbomachinery. UnsteadY loading on c
ompressor and turbine blading was generated by upstream wakes and. add
itionally for compressors, by a rotating inlet distortion. Fast-respon
se hot-wire anemometry and pressure transducers embedded in the airfoi
l surfaces were used to determine the aerodynamic gusts and resulting
unsteady pressure responses acting on the airfoils. This is the first
time that gust response measurements for turbines have been reported i
n the literature. Several different analyses were used to predict the
unsteady component of the blade loading: (1) a classical flat-plate an
alysis, (2) a two-dimensional linearized flow analysis with a ''frozen
gust'' model, (3)a two-dimensional linearized flow analysis with a ''
distorted gust '' model, (4) a two-dimensional linearized Euler analys
is, and (5) a two-dimensional nonlinear Euler analysis. Also for the f
irst time, a detailed comparison of these analyses methods is made and
the importance of properly accounting for both vortical and potential
disturbances is demonstrated. The predictions are compared with exper
iment and their abilities assessed to help guide designers in using th
ese prediction schemes.