A couple reasons why we have not considered running at Bonneville, is the salt crust is to thin for a 14,000 lb vehicle on aluminum wheels (no rubber). The second reason was brought to the attention of racers by Richard Noble is the aluminum wheels on salt becomes to unstable at high speeds and allows the vehicle to yaw enough to get one into trouble. The third reason is (in our case) the salt is so corrosive and eblading to our aluminum fuselage that it would probably tear the aluminum panels off the vehicle. The dirt track, such as El Mirage, Edwards AFB, Alvord Desert and others will absorb the shock wave and reduce the lifting capacity created as you reach Mach 1 speeds. Our CFD analysis conducted by our aerodynamics team (these guys are pretty sharp) indicate we will have about 800 lbs of down force up to near 700 mph at which time we develop about 800 lbs lifting force above 710 mph. CFD similations at transonic speeds vary with such things as air density, temperature, surface rolling resistance, surface density and other factors. It's not easy is it!