{HEAD ~ The tunnel thruster system} includes {TAIL ~ a thruster propulsion mechanism} including a drive unit driving a transmission and propeller assembly located within a thruster tunnel 
includes
{ HEAD ~ The tunnel thruster system } includes { TAIL ~ a thruster propulsion mechanism } including a drive unit driving a transmission and propeller assembly located within a thruster tunnel
HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH