A fuel tank of a spacecraft stores a liquid fuel and a pressurized
propellant gas that drives the fuel out of the tank though a fuel
extraction arrangement including a reservoir or fuel collection container
and a tank outlet. A spiraling or J-shaped or hook-shaped fuel collection
channel and plural obliquely sloping fuel flow channels connect the fuel
collection container to an outlet pipe of the tank outlet. The channels
are configured, dimensioned, oriented and arranged to ensure that fuel
will be retained in the outlet pipe without leaking back into the fuel
tank, even when the tank is oriented horizontally and has a low tank
filling level. These structures produce a capillary pumping effect and
use the surface tension to separate the fuel from the propellant gas, and
allow the inner space of the collection container to be completely filled
with liquid fuel.