  Recent computational results suggest that directional dark matter detectors
have potential to probe for WIMP dark matter particles below the neutrino
floor. The DRIFT-IId detector used in this work is a leading directional WIMP
search time projection chamber detector. We report the first measurements of
the detection of the directional nuclear recoils in a fully fiducialised
low-pressure time projection chamber. In this new operational mode, the
distance between each event vertex and the readout plane is determined by the
measurement of minority carriers produced by adding a small amount of oxygen to
the nominal CS$_{2}$ + CF$_{4}$ target gas mixture. The CS$_2$ + CF$_4$ + O$_2$
mixture has been shown to enable background-free operation at current
sensitivities. Sulfur, fluorine, and carbon recoils were generated using
neutrons emitted from a $^{252}$Cf source positioned at different locations
around the detector. Measurement of the relative energy loss along the recoil
tracks allowed the track vector sense, or the so-called head-tail asymmetry
parameter, to be deduced. Results show that the previously reported observation
of head-tail sensitivity in pure CS$_{2}$ is well retained after the addition
of oxygen to the gas mixture.
