Nice!<p>My understanding is they developed a skip entry option for Apollo but chose not to use it because of the risk.<p>Glide trajectories are also interesting for ballistic missiles. The intuitions you get from looking at aircraft will guide you wrong as the Pershing II could get 25G of acceleration from fins that don’t look like much. The Shuttle had bigger wings for landing, not for entry. Boost-glide is challenging for long range ICBMs but it is a simple upgrade for shorter range missiles that improves performance, confounds performance, and that can acquire and track difficult moving targets like aircraft carriers. See<p><a href="https://en.wikipedia.org/wiki/DF-21" rel="nofollow">https://en.wikipedia.org/wiki/DF-21</a>