Comment by greeneggs

Here's an example where the authors propose doing this for planetary gravity assists, e.g., instead of using Venus for a normal gravity assist, dig into its atmosphere. Everything would need to be folded up first.

"Hypersonic Interplanetary Flight: Aero Gravity Assist"

Al Bowers & Dan Banks, 2006

https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/200900...

Discussed in a podcast here: https://theorbitalmechanics.com/show-notes/al-bowers