Skyhawk 172/Cutlass 172
Flight Crew Instrument; Flight Crew Private
Flight Crew Last 90 Days 30; Flight Crew Total 270; Flight Crew Type 125
Aircraft Equipment Problem Less Severe
General Maintenance Action
Aircraft; Procedure
The airplane my instructor and I were flying had a maintenance issue that caused the replacement of a spring in the rudder linkage system. The original spring was sheared at one end. The replacement spring held up well and the airplane flew about 2 hours after the replacement with another student pilot (I was in the back as a passenger). The airplane was eventually landed for refueling and my instructor and I proceeded to fly in nighttime conditions. After a stop the engine run up checklist (among others) was executed and I verified control free and correct; rudder included. Handling during taxi was normal. After takeoff during pattern left turns the rudder felt normal. Leveling off at cruise at 3500 feet requires removing right rudder pressure needed for coordinated climb out; and that's when I first noticed that the left rudder pedal felt mushy and soft. With no rudder input the airplane would yaw right. Keeping it straight required an amount of left rudder pressure higher than previous flight and yawing to the right would require even more. My instructor confirmed my findings by testing his pedals. Nevertheless rudder authority was not completely lost and we were able to land the airplane without issues. I do not think that it is normal to have the same problem occur twice in a short amount of time; especially since a component was replaced and seemed to operate satisfactorily. The rudder system should be inspected thoroughly. I believe there was some pressure on maintenance staff to keep the airplane flying and generating revenue on one of the first warm and clear spring days of the year. Had we encountered worse weather condition or sustained crosswinds on landing the additional pressure required to slip the aircraft or tracking the runway centerline upon landing might have exceeded pilot's capabilities.
C172 pilot reports the failure of a rudder linkage spring twice in one day and believes that the anomaly should be looked into more thoroughly and that the maintenance staff was under some pressure to get the aircraft repaired the first time.