- Video just got out of processing, you can see my preferred flight path to the Mun and back.. i make it home with 80l of fuel.. P.S. the Beryllium is out of date atm, i managed to make him smaller by 1m and lighter by 1.85t.. so the 'mini' rocket got smaller.. - You dont drop them until 13km (mach I) at the start of your gravity turn, one key component is that you connect the jet booster it with fuel lines to the center stack... This should solve your problem..