  The MCAO Assisted Visible Imager and Spectrograph (MAVIS) Adaptive Optics
Module has very demanding goals to support science in the optical: providing
15% SR in V band on a large FoV of 30arcsec diameter in standard atmospheric
conditions at Paranal. It will be able to work in closed loop on up to three
natural guide stars down to H=19, providing a sky coverage larger than 50% in
the south galactic pole. Such goals and the exploration of a large MCAO system
parameters space have required a combination of analytical and end- to-end
simulations to assess performance, sky coverage and drive the design. In this
work we report baseline performance, statistical sky coverage and parameters
sensitivity analysis done in the phase-A instrument study.
