beachbumflyer's post #41 and cc180's #57 address "knife-edge" flight.
Sorry, but it IS an aerodynamic exercise; the fuselage and fin, rolled to 90 degrees, does form an (albeit imperfect) airfoil. It creates lift (opposite to gravity) because of its AOA, while the wing is now at a zero-lift AOA.
To be fair, since its AOA is 10-15 deg., the prop axis is at this same angle, and thus it's creating some lift too.
So it's not a brute-force "hanging on the prop" condition, but just a poor airfoil with very low aspect ratio making do as a wing.