Aviation Safety Day

What Is Aviation Safety Day?

Every August 12th is "Aviation Safety Day" (航空安全の日, Kōkū Anzen no Hi) in Japan. On August 12, 1985, Japan Airlines Flight 123 (JAL123) — a Boeing 747SR operating from Haneda Airport in Tokyo to Itami Airport in Osaka — crashed into the slope of Mount Osutaka (御巣鷹の尾根) in Gunma Prefecture, killing 520 of the 524 people on board. It remains the deadliest single-aircraft accident in aviation history and one of the most traumatic events in postwar Japanese history. August 12th is observed as a day of remembrance and aviation safety awareness.

The JAL123 Disaster

JAL Flight 123 took off from Haneda at 6:12 p.m. on August 12, 1985 with 509 passengers and 15 crew members aboard. Twelve minutes after departure, a rear pressure bulkhead that had been improperly repaired after a 1978 tailstrike incident failed catastrophically — the blowout destroyed the plane's vertical tail fin and severed all four hydraulic systems, leaving the crew with no conventional flight control. The crew fought to control the aircraft for 32 minutes using differential engine thrust before the plane struck Mount Osutaka at 6:56 p.m. Four passengers survived; 520 died.

Causes and Lessons

Investigation determined that a Boeing repair of the 1978 tailstrike damage had been improper — using a single splice plate rather than the required two-plate repair, leaving the pressure bulkhead structurally weakened. The 7-year time lag between the faulty repair and the catastrophic failure highlighted the importance of thorough maintenance documentation and repair verification. JAL123's lessons have been incorporated into aviation maintenance standards and crew resource management training worldwide, contributing to the dramatic improvement in aviation safety rates since 1985.

Fun Facts

• Survivor survival period: The four survivors — all women, including a 12-year-old girl — were found the morning after the crash in the mountainous crash site accessible only to rescuers. Their survival for approximately 14 hours in the wreckage, in summer heat, was a miracle that provided investigators with direct testimony about the crash sequence and the post-crash conditions.
• Annual memorial: Every August 12th, the crash site on Mount Osutaka is accessible to the public for a memorial service attended by bereaved families, JAL officials, and representatives of Boeing — a solemn annual gathering that maintains memory of the 520 victims and the aviation safety lessons their deaths generated.