Complex sentence: He went into a flat spin at a rotational velocity of about 120 rpm, the g-forces at his extremities having been calculated to be over 22 times the force of gravity, setting another record.
Split into simpler sentences: He went into a flat spin at a rotational velocity of about 120 rpm. The g-forces at his extremities have been calculated to be over 22 times the force of gravity, setting another record.