Home | Question Index | Engine Services | Airframe Services | Logbook Research | Inspections | Articles | Experimental-Projects | About Us

 

Main landing gear retraction cables (conduits) replacement Single (PA24) and Twin Comanche (PA30 & 39).

The main landing gear systems on Piper Comanche and Twin Comanche aircraft are operated by two heavy duty push / pull cable assemblies which transfer the motion of the landing gear actuator to each main landing gear.  Extensive damage to the bottom of the aircraft fuselage, prop(s) and engine(s) is possible should the gear retraction cables fail.  Failure of one conduit can cause extensive damage to corresponding wing, flap, and aileron of the main gear.  Seizing of one cable will prevent operation of the other two landing gear due to the synchronization of the retraction cables and nose gear actuating tube .  Should one retraction cable seize, the emergency landing gear extension system will fail. 

    The are no non-destructive methods to fully inspect the condition of the cables for wearing, fraying, and separation.  The cables can be checked for drag and freedom of movement, but this will not alert the mechanic to excessive wear and fraying inside the cable assemblies.  Corrosion is often the main culprit in failure of the cables.   Replacement of the retracting cables with new assemblies is necessary in order to prevent the failure of the original cables.  The cables cost almost $800 for the pair and require about 18 hours of labor to install and rig.  Installation of new rod end bearings often adds another $100. 

When the retraction cables are removed for replacement, it is a good time to address loose / working bottom wing spar rivets in the inboard section of the wings.  Access to the spar rivets is restricted due to cable anchor brackets securing the outboard ends of the cables.     

 

 

Have a small aircraft problem you can't solve?  Click below to send the question.

submit question

Home | Question Index | Engine Services | Airframe Services | Logbook Research | Inspections | Articles | Experimental-Projects | About Us

Send mail to tim@littleflyers.com with questions or comments about this web site.
Copyright 2000 Little Flyers
Last modified: February 12, 2007