What happened
On May 27, 2017, skydiving and glider operations were being conducted at the Białystok Krywlany Aerodrome (EPBK). During the sequence of events, a jump aircraft was performing parachute deployments. Prior to the flight day, procedures had been established regarding the timing of jumps. As the jump aircraft approached the deployment phase, the pilot broadcasted a warning that jumps would occur in approximately two minutes. Despite this notification, one glider remained within the designated drop zone during the deployment process.
The investigation
The investigation, conducted by the operator, examined the communication and operational procedures in place during the flight day. The investigation established that the incident was reported via an anonymous 'Just Culture' channel. The inquiry focused on the coordination between the jump aircraft and the glider pilots, as well as the effectiveness of radio communications and the adherence to established drop zone clearance protocols.
Findings
Several contributing factors were identified regarding the presence of the glider in the drop zone:
- The glider pilot failed to adhere to established procedures regarding the clearance of the drop zone.
- There was a lack of effective radio communication between the involved aircraft.
- There was an overlap of various radio transmissions at the time the jump aircraft was providing the deployment notification.
Safety action
Following the incident, the flight operations manager and training instructors reviewed the causes of the event. The following safety measures were implemented:
- Pre-flight briefings must now include explicit reminders regarding the obligation to vacate the drop zone and the potential consequences of non-compliance.
- Pilots are required to verify radio communications by actively monitoring the frequency; if no transmissions are heard, the functionality of the radio must be checked.
- A strict prohibition has been placed on switching to different frequencies while operating within the EPBK ATZ.
- Increased vigilance is required during simultaneous glider and skydiving operations.
- The flight manager must confirm the scheduled jump times and re-broadcast this information to all gliders and aircraft operating in the EPBK vicinity.