Apparatus 8 wherein said locking means comprises {TAIL ~ a centrifugal lock} operable above {HEAD ~ a given angular velocity} of said sections to effect said locking action 
Apparatus 8 wherein said locking means comprises { TAIL ~ a centrifugal lock } operable above { HEAD ~ a given angular velocity } of said sections to effect said locking action
OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH