  Radially self-accelerating light exhibits an intensity pattern that describes
a spiraling trajectory around the optical axis as the beam propagates. In this
article, we show in simulation and experiment how such beams can be used to
perform a high-accuracy distance measurement with respect to a reference using
simple off-axis intensity detection. We demonstrate that generating beams whose
intensity pattern simultaneously spirals with fast and slow rotation components
enables a distance measurement with high accuracy over a broad range, using the
high and low rotation frequency, respectively. In our experiment, we achieve an
accuracy of around 2~$\mu$m over a longitudinal range of more than 2~mm using a
single beam and only two quadrant detectors. As our method relies on
single-beam interference and only requires a static generation and simple
intensity measurements, it is intrinsically stable and might find applications
in high-speed measurements of longitudinal position.
