What happened
On 11 July 2003, a Cessna F337G Super Skymaster, registration G-BFJR, was conducting a private flight from East Midlands Airport to Gloucestershire Airport. After joining the right-hand circuit for Runway 27, the pilot attempted to extend the landing gear while on the downwind leg. However, the gear failed to deploy.
In an effort to rectify the situation, the pilot utilized a convex mirror mounted under the port wing-tip to inspect the gear. While the landing gear doors were open, the wheels remained retracted, and the cockpit indicator light remained in the 'up' position. The pilot attempted to use the manual emergency hand pump, performing approximately 150 strokes, but the pump handle required very little resistance, suggesting a lack of hydraulic pressure. Following consultation with a maintenance engineer, the pilot performed high 'g' manoevers, including steep turns and pull-ups, to try and force the gear down, but these efforts were unsuccessful.
After nearly two hours of troubleshooting, the decision was made to land. The pilot executed a steep 4.5-degree approach. Prior to touchdown, both engines were shut down and the propellers were feathered. The aircraft settled onto the runway in a three-point attitude, resulting in no injuries to the pilot, though the underside of the fuselage and the undercarriage doors sustained damage.
The investigation
Following the incident, engineers recovered the aircraft by using airbags to lift the fuselage, allowing the main and nose landing gear to be manually lowered and locked. A post-accident inspection of the landing gear operating systems revealed no mechanical defects or failures in the retraction mechanisms.
However, investigators discovered that the hydraulic reservoir within the landing gear power pack was completely empty. The evidence suggested that the hydraulic fluid had been exhausted after the landing gear doors had opened but before the gear had completed its extension cycle. At the time of the report, the specific cause of the fluid loss had not been identified.