Upon {HEAD ~ the forward movement} of the outer panel from {TAIL ~ its substantially rearward wholly opened position}, a locking mechanism locks the inner panel in a position in which the handgrip remains inaccessible 
from
Upon { HEAD ~ the forward movement } of the outer panel from { TAIL ~ its substantially rearward wholly opened position } , a locking mechanism locks the inner panel in a position in which the handgrip remains inaccessible
OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH