A gas turbine engine rotor assembly having a rotation axis, the rotor assembly comprising: a first body about the rotation axis, the first body having an inner surface radially inward relative to the rotation axis and a seat axially inward the first body and surrounded by the inner surface, the first body having a groove extending circumferentially into the inner surface and spaced axially from the seat, the groove having an inner groove edge proximate to the inner surface and an outer groove edge circumscribing the groove radially outward of the inner surface, the groove at a rated axial location of the first body between the inner groove edge and the outer groove edge facing toward the seat at a normal angle (α N) relative to the rotation axis; a second body about the rotation axis, the second body having an outer surface radially outward relative to the rotation axis and surrounded by the inner surface, an annular gap defined radially between the inner surface and the outer surface and axially between the seat and the groove; a locking washer about the rotation axis in anti-rotational engagement with the inner surface and the outer surface relative to the rotation axis, the locking washer having axially opposite first and second washer surfaces (40', 40") in the annular gap, the first washer surface adjacent to the seat; characterised in that the rotor assembly further comprises a split ring disposed about the rotation axis in the annular gap adjacent to the second washer surface (40"), the split ring having an outer ring edge radially outward relative to the rotation axis, the outer ring edge located inside the groove radially inward of the outer groove edge, the split ring radially engaging the groove at the axial location and resiliently expandable radially outwardly under centrifugal load relative to the rotation axis such that expanding the split ring radially against the groove axially deflects the split ring toward the seat relative to the first body and to the second body so as to axially load the locking washer against the seat. a first body about the rotation axis, the first body having an inner surface radially inward relative to the rotation axis and a seat axially inward the first body and surrounded by the inner surface, the first body having a groove extending circumferentially into the inner surface and spaced axially from the seat, the groove having an inner groove edge proximate to the inner surface and an outer groove edge circumscribing the groove radially outward of the inner surface, the groove at a rated axial location of the first body between the inner groove edge and the outer groove edge facing toward the seat at a normal angle (α N) relative to the rotation axis; a second body about the rotation axis, the second body having an outer surface radially outward relative to the rotation axis and surrounded by the inner surface, an annular gap defined radially between the inner surface and the outer surface and axially between the seat and the groove; a locking washer about the rotation axis in anti-rotational engagement with the inner surface and the outer surface relative to the rotation axis, the locking washer having axially opposite first and second washer surfaces (40', 40") in the annular gap, the first washer surface adjacent to the seat; characterised in that the rotor assembly further comprises a split ring disposed about the rotation axis in the annular gap adjacent to the second washer surface (40"), the split ring having an outer ring edge radially outward relative to the rotation axis, the outer ring edge located inside the groove radially inward of the outer groove edge, the split ring radially engaging the groove at the axial location and resiliently expandable radially outwardly under centrifugal load relative to the rotation axis such that expanding the split ring radially against the groove axially deflects the split ring toward the seat relative to the first body and to the second body so as to axially load the locking washer against the seat.