What happened
The aircraft was cruising when it encountered turbulence. Shortly after this encounter, the pilot experienced significant elevator control difficulties accompanied by vibrations in the control yoke. Recognizing the severity of the situation, the pilot declared an emergency and requested vectors to the nearest airport.
Mountain Home Air Force Base Rapid Response Control provided vectors directing the flight to Glenns Ferry Airport. During the approach phase, the pilot sighted large 'X' marks on the runway, which indicated that the airport was closed. However, due to the nature of the emergency, the pilot elected to continue the landing.
Conditions were deteriorating into dusk. As a result, the pilot did not see obstructions on the runway, specifically large dirt mounds, until the aircraft was already committed to the landing. The pilot attempted to steer clear of these obstacles during touchdown and roll-out but was unable to avoid them. The aircraft collided with one or more of the mounds before coming to a complete rest.
The investigation
Post-accident examination revealed that the elevator tab control rod end had torn free from the tab horn. Inspection of the horn showed evidence of previous wear that had necessitated the installation of an oversized bearing. Continued wear reduced the cross-section of the component, rendering it unable to withstand the flight loads induced by the turbulence.
Additionally, it was noted that Mountain Home Air Force Base was not included on the Class B NOTAM distribution list at the time of the mishap.