If we use 4x most of the time and can fly up to 70km, so I have calculation that it is possible but crazy. In this case we need 6000-14000 of delta V (depends on precision).
Speed should be 2616-2800 m/s and radial in thrust is about 0.1-1 of Gravity if you can handle it in 4x while flying.
Practically it means hours of practice and some calculations and possibly using KAL-1000 with premade settings.
I can give you my very unprecisious calculations of it's possibility if you need it