Finally, this arrangement facilitates maintenance operations, as {TAIL ~ a service engineer} can visually monitor {HEAD ~ the elevator car} or the shaft itself from the drive system 
Finally , this arrangement facilitates maintenance operations , as { TAIL ~ a service engineer } can visually monitor { HEAD ~ the elevator car } or the shaft itself from the drive system
OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH