The single crystal blades are provided with a root portion which contains a recess or {HEAD ~ cavity} which conforms closely to {TAIL ~ the disk protrusion} 
The single crystal blades are provided with a root portion which contains a recess or { HEAD ~ cavity } which conforms closely to { TAIL ~ the disk protrusion }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD OTH REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL