Overview
On 17 September 2015, a Boeing 737-400 operated by an unspecified airline was involved in an incident at EPBY (Bydgoszcz Ignacy Jan Paderewski Airport). The aircraft was in the process of pushback from the parking position with engines running when ground personnel observed white, dense smoke emanating from the area of the right main landing gear. In response, the flight crew shut down both engines and initiated an evacuation of the 160 passengers under the assistance of the airport fire service.
Details
After the aircraft was secured, maintenance staff inspected the main landing gear nacelle. They discovered a rupture in a brake line of the right main landing gear assembly. The smoke had been caused by the crew's use of the parking brake, which forced hydraulic fluid through the broken line onto the hot brake components. The fluid vaporized and created the visible smoke.
As a corrective action, the damaged brake hose was replaced. Additionally, wheel assemblies numbers 3 and 4, including their brakes, were replaced. The hydraulic system was replenished with fluid, followed by a leak test. The aircraft was subsequently released for unrestricted continued operation.
Cause
According to the investigation report, the incident was caused by a rupture of a brake line, which led to leakage of hydraulic fluid onto the hot brake assembly. The resulting vaporization of the fluid produced the observed smoke. No safety recommendations were issued by the commission.