@BowsacNoodle @Marakus @Racist_Columbo Would be a huge ass balloon to carry a spacecraft though, which is why I am suggesting something with a bit more oomph to it, not necessarily propeller aircraft. Could be awesome if it worked though.

I'm also under the impression that the first handful(s) of kilometers of altitude and thousands of meters per second of speed are by far the toughest ones for the spacecraft to work through because of thicker atmosphere and lack of intertia when having to start from zero. Wouldn't it be a significant boon for the spacecraft to effectively have bypassed that? Or is it actually not that relevant?