Sail Plane
Flight Crew Private
Flight Crew Last 90 Days 35; Flight Crew Total 1710; Flight Crew Type 255
Training / Qualification; Troubleshooting
Aircraft Equipment Problem Critical
Flight Crew Became Reoriented; Flight Crew Took Evasive Action; Flight Crew Landed As Precaution; General Maintenance Action
Aircraft
The glider is a two seater. The two primary cables from the rudder go straight to the front seat pedals; and the rear seat pedals connect by a short cable to each right and left primary cable. I was in the rear seat when the left rudder pedal connection to the rudder cable lost tension while applying corrective pressure in a right turn. The cables from the rudder to the front seat were unaffected; and the glider was fully controllable. Only the rear seat connection to the left cable was lost. A bit startling. The rear seat connector cable goes through an 'S' shaped metal tube with a plastic sleeve to improve movement. The tube part closest to the pedal had worn through. Corrective action included immediate slowing and rolling to level flight. The front seat pilot took over rudder control and normal flight was maintained to landing. Stabilizing the flight was priority #1 then descending to landing was next once control was confirmed. We were airborne less than 1.5 hours for the entire flight.
The reporter stated that front and aft cockpit rudder cables are mechanically attached; with the front cockpit cable being primary and directly connected to the rudder with a solid cable. The aft cables are sistered to the front cables. There was no loss of control during this event. The reporter stated that newer glider models from this manufacturer have been redesigned to prevent this type of failure; which has occurred before and is known to be a potential issue.
An ASH-25 Glider's aft cockpit left rudder cable became disconnected during flight; but the aircraft was fully controllable from the front cockpit.