  The eigenproblem for thin shells of revolution under uncertainty in material
parameters is discussed. Here the focus is on the smallest eigenpairs. Shells
of revolution have natural eigenclusters due to symmetries, moreover, the
eigenpairs depend on a deterministic parameter, the dimensionless thickness.
The stochastic subspace iteration algorithms presented here are capable of
resolving the smallest eigenclusters. In the case of random material
parameters, it is possible that the eigenmodes cross in the stochastic
parameter space. This interesting phenomenon is demonstrated via numerical
experiments. Finally, the effect of the chosen material model on the
asymptotics in relation to the deterministic parameter is shown to be
negligible.
