19980625044719I

Attachement to section 33, incident report, describing gear-up landing at Kalispell Montana, Cessna 182RG, N736ZV. The helena FSDO became aware of N736ZV having bee damaged during a gear-up landing at Kalispell, Montana when a request for a ferry permit was received on August 8, 1998. The request was made by beegles aircraft, in greeley, Colorado, the facility that was going to effect the repairs. The pilot of the aircraft was contacted by phone and asked to describe the occurrence. He stated that during the takeoff roll, as he gegan to add back pressure to rotate, he bacame aware of the gear retraction cycle beginning. He said he had not selected gear-up prior to the retraction cycle starting. He could offer no explanation as to why the retraction cycle began, but said he may have possibly bumped the gear lever with his knee, although he does not remember doing so. While distracted by the unusual operation of the gear, he allowed the nose to settle enough that the tips of the propeller contacted the runway. Then this occurred, he pulled the aircraft clear of the runway, but rather than continue to fly with a damaged prop, reduced power and landed the aircraft with the gear retracted. Bob thomason, of beegles aircraft was contacted by phone to discuss the incident. The discussion centered around the possibility of the landing gear retraction cycle occurring without selecting the gear up position with the gear selector handle. Mr. Thomason said he recalled a customer bringing a similar aircraft to him for gear system inspection as a result of the same situation occurring during takeoff. Mr. Thomason said his customer experienced landing gear retraction during liftoff in his aircraft without selecting gear up. He told Mr. Thomason the gear came up by itself after liftoff, he continued the takeoff, and returned to the airport after moving the gear selector up and then down again to extend the gear, landing without incident. Beegles inspected the gear system and returned the hydraulic power pack to the manufacturer for inspection, suspecting the power pack may be faulty. The manufacturer sent the assembly back, reporting no discrepancy found, and suggested the gear selector valve assembly be inspected for wear or malfunction. This assembly was determined to have leakage in the valve machanism great enough to allow hydraulic pressure to be applied to the retract ion side of the hydraulic system to begin the retraction cycle with the gear selector in the down position. Mr. Mark tyler, of Cessna aircraft, was contacted regarding a defective gear selector assembly allowing hydraulic pressure to be applied to the retraction side of the gear actuating system. He said he had not heard of that ocurring, but said it could be possible if the valve assembly was worn or defective. Mr. Thomason called on January 25th and reported beegles aircraft had completed their inspection of the gear system on N736ZV and found no obvious discrepancies. No substantial cause for this incident is apparent. The cause of this incident is unknown.