For what itīs worth, this is a quote from an AAIB investigation report concerning flight data recorder sample rates:
Figure 1 shows a time history of selected parameters recovered from the DFDR fitted to G-RJXC recorded during the incident landing. Pitch Attitude and Lateral Acceleration are sampled at 0.25 second intervals, Normal Acceleration at 0.125 second interval, Roll Attitude at 0.5 second interval and Altitude, CAS, Groundspeed and Heading at 1 second intervals