You can try several scientifically reasonable simulations, or make you own,
using the PC and mac versions of X-plane, from Laminar Research. The free
downloadable demo lets you fly for five minutes at a time, and has mars
simulations with realistic grav and atmosphere. The mars planes are rocket
powered, but players have made some of their own verisions available for free
download. or, s I said, you can use the included planemaker utility to
construct and test your own designs.