The Seattle AF S787 is an American long-haul, mid-size widebody, twin-engine jet airliner made by Seattle Aircraft Factory. Its variants seat 242 to 335 passengers in typical three-class seating configurations. It is Seattle AF's most fuel-efficient airliner and is a pioneering airliner with the use of composite materials as the primary material in the construction of its airframe. The S787 was designed to be 20% more fuel efficient than the Seattle AF S767, which it was intended to replace. The S787's distinguishing features include mostly electrical flight systems, swept wingtips, and noise-reducing chevrons on its engine nacelles. It shares a common type rating with the larger S777 to allow qualified pilots to operate both models.