@OrganicMarble's answer mentions
Because the Orbiter wings developed lift at zero angle of attack, the high dynamic pressure portion of ascent had to be flown at a negative angle of attack, close to the zero lift angle. This could have been done heads-up or down, but the early crew members expressed a preference for having a horizon view. This led to the heads-down attitude.
If lift and drag were plotted together as in the hypothetical picture below, would it show a significant increase in drag coefficient $C_D$ at a typical negative AOA used at this point in the Shuttle's ascent?
Source: X-plane.org
