What happened
On December 28, 2016, a Piper PA-28RT-201T Turbo Arrow, registration EC-EGX, was performing a local IFR flight departing from and returning to Burgos Airport (LEBG). While on approach to runway 04, approximately 10 nautical miles from the field, the pilot experienced a sudden impact on the propeller and the lower section of the aircraft. The impact caused the propeller to vibrate significantly and caused the autopilot to become locked in roll control.
In response to the vibrations, the pilot reduced power to stabilize the aircraft. During the subsequent attempt to extend the landing gear, the landing gear transit alarms continued to sound, and the gear failed to deploy. The pilot attempted to troubleshoot the issue by cycling the gear selector and using the emergency extension lever, but the nose gear remained stuck. Due to the inability to use runway 04, the pilot declared an emergency and diverted to runway 22, performing a gear-up landing. The pilot was uninjured and evacuated the aircraft independently.
The investigation
The CIAIAC investigation focused on the mechanical state of the landing gear and the sequence of emergency procedures. Upon inspection in a hangar, investigators found that the nose gear and main gear systems were fully functional. The nose gear doors had been so deformed that they had to be pried open with a lever to allow the gear to extend.
Investigators examined whether the deformation was caused by the initial mid-air impact or by the impact with the runway during the gear-up landing. The investigation noted that the damage from the mid-air impact was difficult to isolate because the subsequent gear-up landing and the towing of the aircraft to the hangar had caused further erosion and deformation to the airframe.