What happened
On March 6, 2015, an incident occurred at Warsaw Chopin Airport (EPWR) involving a Boeing 737-500 during the boarding process. After passengers had boarded the aircraft but before the forward passenger doors could be closed, a malfunction occurred with the passenger boarding bridge.
As a ground worker was retrieving the "safety shoe" (a protective device) from beneath the door, the boarding bridge suddenly descended approximately 45 cm within a period of one to two seconds. The bridge moved downward and rested against the fully open aircraft doors. No passengers or ground personnel sustained injuries during the event.
The investigation
The investigation was conducted by the airport management and was based on CCTV footage and statements from the personnel operating the boarding bridge. Investigators found that following the sudden movement, the bridge operator did not immediately engage the emergency stop button. Consequently, the automated positioning system continued to operate, attempting to realign the bridge with the aircraft. The system was only fully immobilized after the emergency stop was manually activated.
Findings
- The primary cause of the incident was a malfunction of the automatic positioning system sensor, which generated an erroneous signal that triggered the rapid descent of the bridge.
- The automated system remained active and attempted to continue positioning operations until the emergency stop was pressed.