What happened
On 27 January 2009, Japan Airlines Flight 950, a Boeing 747-40 and registration JA8074, was climbing through 7,000 feet near the Anyang VOR in the Republic of Korea. After maintaining a level flight at 7,000 feet, the flight crew received instructions to climb to FL230. As the aircraft resumed its climb, the increased pitch attitude caused a service cart on the upper deck to slide backward, exceeding the capacity of its brakes.
The sliding cart struck a seat and tumbled, causing hot beverages stored on the cart to spill. The liquid struck a passenger in seat 19C, resulting in a second-degree burn to their right arm.
The investigation
The ARAIB investigation examined the flight sequence, cabin service procedures, and the mechanical specifications of the service cart. Investigators reviewed the flight data recorder and air traffic control communications, which confirmed the aircraft was in a climbing phase when the incident occurred. The investigation also looked into the operational manuals of Japan Airlines, specifically regarding seat belt sign procedures and cabin attendant safety duties.
Findings
- The primary cause of the incident was the aircraft's pitch attitude during the climb exceeding the braking capability of the service cart.
- The flight crew was unaware that the pitch required for a climb after level flight could overcome the cart's brakes.
- At the time of the movement, both cabin attendants responsible for the upper deck were away from the cart.
- The airline's safety manuals lacked specific instructions regarding the risks of leaving a service cart unattended during service or the limitations of the cart's braking system during climbs.
- Hot beverages were positioned on the top of the service cart, increasing the risk of spillage during movement.