  We examine the flaring behaviour of the cataclysmic variable AE~Aqr in the
context of the `magnetic propeller' model for this system. The flares are
thought to arise from collisions between high density regions in the material
expelled from the system after interaction with the rapidly rotating
magnetosphere of the white dwarf. We calculate the first quantitative models
for the flaring and calculate the time-dependent emergent optical spectra from
the resulting hot, expanding ball of gas. We compare the results under
different assumptions to observations and derive values for the mass,
lengthscale and temperature of the material involved in the flare. We see that
the fits suggest that the secondary star in this system has Population II
composition.
