As Peter (sibling) mentioned, the force would not be equal across the surface. If it was propelled straight (i.e. orthogonal to the radius of the Earth), then there'd be some serious eddy effects of airflow around the circular edge (cross-section).

Probably the best thing that could happen from a NOT-deform standpoint would be to have it launched at an angle, i.e. as if a quarter fell on the Earth and landed on it's side (neither face). This would present the smallest and most uniform cross-section possible (as opposed to the face of the quarter looking into space, the rim/edge of the quarter points up skyward).

Also air resistance is extremely tricky at "normal" speeds, let alone at 10km/s+, and I think the real factor would be the currents of air around the edges, massive turbulence = massive amounts of friction/heat on the edges. It would be a mess! Hopefully that makes it a little clearer :)