Incident Overview
A pilot reported being unable to extend the landing gear using either the normal or emergency systems. After repeated attempts to lower the gear, he decided to land with the gear configured in a free-fall position. On final approach, he shut down and feathered both engines.
Landing and Damage
During touchdown, the wheels were forced upward from their free-fall position and into the wheel wells. Consequently, the aircraft sustained substantial damage.
Investigation Findings
An investigation revealed that the landing gear slide tubes, slides, and actuating chains contained an excessive accumulation of grease, dirt, and grit. Additionally, rust accumulation was found on the slide tubes.