S-TEC INSTALLS UNIQUE FLIGHT CONTROL SYSTEM After a year and a half of service in the Goodyear Airship "Spirit of Akron" the S-TEC fibre optics flight control system is getting high marks for performance. Goodyear installed the system in late 1997 to replace an old system that had developed unacceptable performance and maintenance problems. The performance and reliability of the S-TEC flight control system takes on added importance since the mechanical cable control system is removed from the airship. Fibre optic cables from the pilot station to the actuators make this system a fly-by-light, triple redundant flight control system. After the year and a half of operation, no failure has occurred in the system, and no problems have been encountered. The system consists of: 1. One flight control panel 2. Two pilot/copilot side-stick controllers 3. Six mixers 4. Six controllers 5. And two triple redundant servo actuators. The two actuators, a port actuator and a starboard actuator, respond to control stick commands processed through a mixer and controller. The port actuator is coupled to the upper starboard and lower port ruddervators, while the starboard actuator is coupled to the upper port and lower starboard ruddervators. An emergency mode provides full authority force control of the ruddervators should a single point failure of the position sensors occur. The S-TEC FCS also provides pitch trim for the airship. The Spirit of Akron "Blimp" is based at Wingfoot Lake Airship Base, which is just outside Akron, Ohio. The airship is 205.5 feet long and has a volume of 247,800 cubic feet. Two 420 hp turboprop engines with ducted and vectored fans propel the airship, and the Spirit of Akron is faster and more maneuverable than any other airship flying today with a maximum airspeed of 65 m.p.h.. It normally operates at altitudes of 1,000 to 3,000 feet.