Friction is generated during {HEAD ~ operation} of {TAIL ~ the engine} between the outer surface of the friction damper and the undersides of two adjacent shrouds 
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Friction is generated during { HEAD ~ operation } of { TAIL ~ the engine } between the outer surface of the friction damper and the undersides of two adjacent shrouds
OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH