Describe the advantages of using 'Self-Locking' spiral retaining rings in high-vibration aerospace environments.

Self-locking spiral rings feature a small tab on the inner turn that 'clicks' into a slot on the outer turn. This mechanical interlock prevents the ring from expanding and vibrating out of the groove under intense centrifugal forces or axial impact loads. In turbine engines, where vibrations can reach several thousand Hz, a standard spiral ring might 'walk' around the groove and eventually dislodge. The self-locking feature ensures that the ring remains seated even if the shaft reaches speeds that would normally exceed the ring's centrifugal capacity $V$.