What happened
On January 4, 2005, a Cessna T337H, registration OB-1274, departed from the Ciudad Nueva Ilo camp for Tacna International Airport. During the approach to Tacna at approximately 18:25 UTC, the pilot attempted to extend the landing gear but discovered that the right main landing gear failed to deploy. The landing gear indicator light remained unlit, and an audible warning alarm activated whenever power was reduced during the approach.
After requesting a low-altitude pass over the runway to verify the gear position, air traffic control confirmed that while the nose gear and left main gear were down and locked, the right main gear remained in the up position. The pilot performed emergency checklist procedures twice in an attempt to extend the gear, without success. To manage the situation, the pilot remained airborne for approximately 40 minutes to consume fuel and reduce the aircraft' and weight.
At approximately 19:00 UTC, the pilot declared an emergency and prepared for a forced landing. During the final approach, the pilot shut down the rear engine and feathered the propeller. Upon touchdown, the aircraft contacted the runway on the left main gear and nose gear first. As the aircraft decelerated, the right wing tip struck the ground, causing the aircraft to veer right and exit the runway, coming to a stop approximately 100 meters from the initial contact point. There were no fatalities and no injuries to the pilot or the passenger.
The investigation
The CIAA investigation focused on the failure of the right main landing gear deployment mechanism. Investigators examined the hydraulic system and identified a rupture in the hydraulic line connected to the right main landing gear actuator cylinder. The investigation noted that the hydraulic line was made of aluminum, a rigid material that is not highly flexible.
Technical analysis revealed that the line was pre-formed at the factory and was subject to significant vibrations caused by the pressurization and depressurization cycles of the hydraulic system. Furthermore, the investigation considered that the complexity of the pre-formed shape and the handling of the component during maintenance inspections may have contributed to the development of fatigue at the connection points.