A multifunction integrated power unit for {HEAD ~ use} aboard aircraft provides the functions both of an auxiliary power unit and of {TAIL ~ an emergency power unit} while being smaller, lighter, and less expensive than the two units it replaces 
A multifunction integrated power unit for { HEAD ~ use } aboard aircraft provides the functions both of an auxiliary power unit and of { TAIL ~ an emergency power unit } while being smaller , lighter , and less expensive than the two units it replaces
OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH