History of Flight
On 23 February 2009, a Boeing McDonnell Douglas MD-90 aircraft, registered PK-LIO, operated by PT. Lion Mentari Air (Lion Air) as flight LNI-972, was scheduled to depart Polonial Airport Medan at 16.35 LT (09.35 UTC) for Hang Nadim Airport, Batam. The crew consisted of two pilots and four flight attendants. There were 156 passengers: 148 adults, four children, and four infants.
After takeoff, during the landing gear up procedure, the pilot noted a red light for the nose gear on the landing gear panel. The pilots reported that they recycled the landing gear, and the subsequent cockpit indication showed the landing gear in the up and locked position. The flight continued to the planned destination.
During final approach at Batam, the pilots observed that the red light for the nose gear indicator was illuminated. The pilot in command (PIC) decided to conduct a go-around and hold to perform the emergency checklist in an attempt to extend the nose landing gear. After multiple attempts, the nose landing gear red indicator remained illuminated. The PIC decided to make an emergency landing on runway 04 with the nose landing gear not extended. The aircraft subsequently stopped on runway 04 on the centerline.
Emergency personnel and vehicles from Hang Nadim Airport prepared for the emergency and laid foam on the runway before the aircraft landed to eliminate fire hazard. The passengers and crew evacuated via the left front door escape slide. None of the occupants were injured.
Investigation Findings
The initial investigation found that the nose landing gear spray (water) deflector had fractured, jamming the nose landing gear in the up position. Further examination revealed that the fracture surface showed a dark-colored portion, indicating a pre-existing crack. This crack was induced by previous contact with an object, such as a wheel chuck or other object that could strike the deflector during aircraft parking. The deflector had insufficient ground clearance, making it vulnerable to impact.
Cause
The failure of the nose landing gear spray deflector due to a pre-existing crack, which was induced by previous contact with an object, resulted in the nose landing gear being unable to extend.