Incident Summary
According to the captain, the flight proceeded without incident until the final approach to land on runway 21 at the destination airport. After completing the landing checklist, the captain noted that the main landing gear position indicator lights were illuminated, indicating the main gear was down and locked. However, the nose gear position indicator light was illuminated, indicating the nose gear was unlocked, and the hydraulic system remained operational. The captain aborted the approach and executed a go-around. During the go-around, hydraulic caution lights illuminated. The captain contacted Beaufort approach to advise them of the situation and requested a fly-by of the Beaufort control tower to visually confirm the nose landing gear position. The control tower confirmed that the main landing gear was extended and the nose gear was retracted. The captain declared an emergency, received radar vectors, and diverted to Savannah International Airport, where an emergency landing on runway 9 was performed.
Post-Incident Examination
Post-flight examination of the aircraft revealed that the nose wheel doors were scraped and the nose wheel tire was blown. The pilot reported no flight control malfunctions. A total of eighteen laboratory physical tests, a kinematic study, several general inspections, and a conformity check were conducted in an effort to duplicate the condition that occurred on 560-5132. Seven tests were performed on a nose gear assembly from a Cessna test article, and eleven tests were performed on the nose gear assembly from 560-5132, including leak tests and service procedure tests.
Testing and Analysis
During the laboratory environment tests, the field failure could not be duplicated. The testing included a kinematic study and various inspections to replicate the observed condition. Despite extensive efforts, the exact malfunction that led to the nose gear remaining retracted during approach was not reproduced under controlled conditions.