  This work describes first commissioning results from the Cornell Brookhaven
Energy Recovery Test Accelerator Fractional Arc Test. These include the
recommissioning of the Cornell photo-injector, the first full energy operation
of the main linac with beam, as well as commissioning of the lowest energy
matching beamline (splitter) and a partial section of the Fixed Field
Alternating gradient (FFA) return loop featuring first production Halbach style
permanent magnets. Achieving these tasks required characterization of the
injection beam, calibration and phasing of the main linac cavities,
demonstration of the required 36 MeV energy gain, and measurement of the
splitter line horizontal dispersion and R56 at the nominal 42 MeV. In addition,
a procedure for determining the BPM offsets, as well as the tune per cell in
the FFA section via scanning the linac energy and inducing betatron
oscillations around the periodic orbit in the fractional arc was developed and
tested. A detailed comparison of these measurements to simulation is discussed.
