What happened
On August 7, 2019, a Hawker Beechcraft 390 (Premier I) departed from Hamburg Airport on a non-commercial flight bound for Karlsruhe/Baden-Baden. Shortly after takeoff from runway 33, at an altitude of approximately 500 ft AMSL, the flight crew noticed white smoke developing near the right cockpit windshield.
As the smoke increased and began to obstruct the crew's view of the flight instruments, the pilots donned oxygen masks and smoke goggles. The pilot flying handed control of the aircraft to the copilot. To ensure safety, the crew decided to abort the climb and return to Hamburg. Rather than performing the full emergency checklist to isolate the source of the smoke, the crew prioritized a rapid landing to minimize exposure.
The aircraft declared an emergency and performed a visual approach to runway 23. Following the landing, the crew shut down the engines and electrical power. While the pilot in command evacuated the passengers, the copilot remained on board and used a Halon fire extinguisher on the right windshield, which caused the inner pane to shatter.
There were no injuries to the two pilots or the three passengers on board.
The investigation
The BFU examined the aircraft's electrical systems and the windshield assembly. Investigators found evidence of heat damage on the terminal block responsible for supplying electricity to the right cockpit windshield heating element.
Further analysis of the windshield, conducted in coordination with the manufacturer and the NTSB in the United States, focused on the electrical circuit. The investigation confirmed that while most wiring remained intact, the heat development originated at the ground wire connection.
Findings
- The primary cause of the smoke development was a loose connection between the ground wire and the terminal block within the windshield heating system.
- This loose connection resulted in high heat generation, leading to the observed smoke and the subsequent degradation of cockpit visibility.