What happened
On January 29, 2006, a Diamond DA40 CATANA, registration OE-KKS, was conducting a planned VFR flight from Dresden, Germany, to Neusiedl am See, Austria, at flight level 600. While operating within the Prague TMA, approximately 5km south of the Zbraslavice VOR, the aircraft experienced a failure in its electrical power systems.
The pilot in command (PIC) notified Prague Flight Information Center (FIC) of the malfunction and requested an emergency landing at the nearest suitable airfield. Following instructions from Prague Approach, the pilot was directed to the military airfield at Čáslav (LKCV). During the descent and approach, the crew failed to make contact on the Čáslav Approach frequency or the international emergency frequency (121.5 MHz). The pilot eventually established contact on the final approach for runway 137, though the transmission was noted as illegible. The aircraft landed safely at 12:13 UTC without further incident.
The investigation
The ÚZPLN investigation focused on the cause of the electrical system failure and the subsequent loss of radio communication. The investigation established that the aircraft's electrical power supply was interrupted, which directly caused the onboard radio station to operate intermittently. Technical inspections were conducted alongside technicians, confirming that the onboard electrical power source had failed.
Findings
- The primary cause of the event was a technical failure involving the loss of the onboard electrical generator.
- The intermittent radio communication was a direct consequence of the electrical power failure affecting the onboard radio equipment.
- The pilot held the appropriate qualifications and medical certification for the flight.
- The aircraft was airworthy and had undergone a periodic inspection five flight hours prior to the event.
Safety action
- The faulty generator was replaced following the incident.