Incident
During the landing approach, the pilot attempted to extend the landing gear using the normal hydraulic extension system but was unsuccessful. The emergency extension system was then activated, but it also failed to lower the gear. With no landing gear indication, the pilot performed a gear-up landing. After the aircraft stopped, the hydraulic reservoir was refilled, and the emergency extension system was then used successfully to extend the landing gear.
Hydraulic System Failure
Examination of the landing gear system revealed a ruptured line on the right main landing gear door. This rupture had caused a complete loss of hydraulic fluid, which disabled both the normal and emergency extension systems while airborne. The failed line had a manufacture date of 1979, matching the year the aircraft was manufactured.
Maintenance Records
Piper Aircraft Corporation maintenance procedures require the landing gear door line to be pressure tested after ten years in service and every five years thereafter. A review of the aircraft's logbook records showed no evidence that the failed line had been pressure tested in 1994, which would have been due after ten years of service and at subsequent five-year intervals.