The Short 360 is a 36-seat derivative of the 30–33 seat Short 330. In high density configuration, 39 passengers could be carried. The two Short airliners have a high degree of commonality and are very close in overall dimensions. The later 360 is easily identified by a larger, swept tail unit mounted on a revised rear fuselage. The 360 has a 3'0" (91 cm) fuselage "plug" which gave sufficient additional length for two more seat rows (six more passengers), while the extra length smoothed out the aerodynamic profile and reduced drag. Seating is arranged with two seats on the starboard side of the cabin and one seat on the port side. The 360's power is supplied by two Pratt & Whitney PT6A-65Rs. The development was announced in 1980, with the prototype's first flight on 1 June 1981 and type certification awarded on 3 September 1981.