Accident Overview
On November 29, 2013, at about 1500 Pacific standard time, a Cessna 210, registration N6575X, experienced a landing gear malfunction and subsequently made a partial gear-up landing at Florence Municipal Airport (6S2) in Florence, Oregon. The airplane was substantially damaged. The airline transport pilot and his passenger were not injured. Visual meteorological conditions prevailed, and no flight plan was filed for the local personal flight, which had originated from 6S2 about 1400.
The pilot reported that prior to the flight, the landing gear actuator had been rebuilt, and all subsequent ground tests were uneventful. The pilot and passenger then conducted a local maintenance test flight. During the flight, the landing gear retracted normally; however, when it was extended, the left and right main landing gear would not extend. The nose wheel landing gear extended and locked in the down position. Despite numerous attempts, the pilot was unable to raise or lower the landing gear.
The pilot initiated a partial gear-up landing on Runway 33. During the landing roll, the left horizontal stabilizer struck the runway. Postaccident examination by the pilot revealed that the left horizontal stabilizer and elevator were bent upward about 10 degrees. The airplane was recovered to a secure location for further examination.
Hydraulic System Examination
On December 19, 2013, a Federal Aviation Administration (FAA) inspector examined the airframe at the owner's hangar. The airplane was placed on jacks, and a hydraulic mule was attached to the hydraulic system. Despite multiple attempts, the landing gear would not retract or extend. The hydraulic power pack was subsequently removed and retained for further examination.
The hydraulic power pack, part number EA1332-1, serial number 699, was examined by APPH in Wichita, Kansas, under FAA supervision. The examination revealed that all safety wire was intact and no evidence of system contamination was found. The power pack was functionally tested on a test bench using the Cessna 210 Service Manual instructions. During the test, the system allowed the landing gear to extend but would not allow the flaps to extend or retract. Additionally, the unit did not allow the landing gear to retract or build up any pressure with the hand pump. Further examination revealed that the number one thermal relief valve lost pressure after it was relieved. Four poppet assemblies did not retain pressure during the test. The hand pump assembly spring was not correct for the make/model hydraulic power pack. No additional anomalies were noted.
Maintenance History
Review of the airplane's maintenance logbook records revealed an entry dated April 8, 2013, at tach time 1,854.9 hours and airframe total time 1,885.7 hours, which stated in part: "repaired leak in hydraulic power pack." No further entries regarding the hydraulic power pack were noted in the logbook.