What happened
On February 1, 2020, a Sport Star RTC, registration SP-AZI, departed from Warsaw (EPBC) airport. Shortly after liftoff, the pilot observed smoke spreading throughout the cockpit. The pilot identified the smoke as exhaust fumes and immediately notified the EPBC information service, expressing the intent to land on runway 10.
To manage the situation, the pilot initiated a left turn while simultaneously removing his mask, reducing engine power, and opening the windows. These actions successfully prevented further smoke from entering the cabin. The pilot completed a safe landing on runway 10 and taxied the aircraft to a hangar. A subsequent inspection of the aircraft revealed that the exhaust pipe tip, located downstream of the silencer, had detached along a weld seam.
The investigation
The investigation focused on the structural integrity of the engine's exhaust system. The investigators located the detached exhaust pipe tip on the runway. The examination confirmed that the engine had previously undergone a service following manufacturer bulletin RTC-051b, which mandated the replacement of flexible exhaust pipes with more rigid pipes featuring ball joints. At the time of the incident, the aircraft had flown only 6 hours since the implementation of this modification.
Findings
- The direct cause of the incident was the separation of the exhaust pipe tip along the circumferential weld seam.
- A contributing factor was the installation of more rigid exhaust pipes with ball joints, as specified by the manufacturer's service bulletin, which may have influenced the stress on the component.