Incident
A Cessna P210N Centurian, registration G-VMDE, experienced a landing gear system malfunction on 8 October 2003 at 0930 hrs, northwest of Cardiff Airport, Wales. The aircraft was conducting a private flight from Cardiff to Abbeyshrule Airport, Ireland, with a single crew member and no passengers. The pilot, holding a Commercial Pilot's Licence, aged 45, had 4,200 total flying hours (600 on type).
Sequence of Events
The takeoff and landing gear retraction proceeded normally. While climbing through 3,000 feet, the pilot heard a bang and felt a thump apparently from the rear fuselage. Using the mirror on the port wing, he observed that the left main landing gear door was partly open. Simultaneously, the electrically driven hydraulic pump for the landing gear began to operate. The pilot immediately selected the landing gear down, but the gear remained retracted. Suspecting hydraulic fluid loss, he pulled the circuit breaker for the pump. The pilot declared an emergency and requested a return to Cardiff. He then lowered the landing gear using the hand-operated pump. The gear extended and the three green lights illuminated, but instead of the pump stroke becoming stiff, it felt limp. The landing at Cardiff was successful, and the aircraft was taxied to the ramp.
Post-Flight Inspection
An inspection after landing revealed that the end cap of the main gear door accumulator had detached, causing a small dent in the internal fuselage. The accumulator body was displaced in its mounting. The hydraulic reservoir was empty, and hydraulic fluid was found in the landing gear bay and on the fuselage side. The accumulator end cap is normally retained by a circlip. There was no record of recent maintenance on the accumulator.
Probable Cause
The reason for the end cap becoming detached was not determined.