During the HALO-(AC)³ aircraft campaign in 2022, onboard of Polar 6 aircraft, refractory black carbon (BC) mass and number concentration was measured by a single particle soot photometer (SP2) in the mass equivalent diameter range of 70-675 nm. The instrument was installed behind the counter-flow virtual impactor (CVI) inlet, and therefore measured the BC properties of cloud residuals when the aircraft flew through clouds and the counter flow was switched on. During out-of cloud measurements, the counter flow of the CVI was switched off and the instrument measured the total aerosol's BC properties. In the data files, the column CVI_flag indicates if total aerosol was sampled (value of 0), cloud residuals were sampled (value of 1). A CVI_flag value of 2 indicates that the inlet counter flow was currently switched on or off and therefore the measurement is not valid. The provided time resolution is 3 seconds.