What happened
On July 18, 2015, an experienced skydiver with 1,507 jumps was performing a tandem jump with a passenger at the EPNC landing field in Chrcymno. The jump proceeded normally until the deployment of the second canopy. While the canopy inflated correctly, the skydiver noticed a lack of resistance when pulling down the left steering line. Upon inspection, the skydiver observed that the left trailing edge of the Sigma II 370 canopy appeared as though it had been braked by approximately 50-70%.
Due to the canopy's tendency to spontaneously turn to the left, which presented a landing hazard, the skydiver initiated emergency procedures. The main canopy was jettisoned, and the reserve parachute was deployed. The landing was completed on the operational part of the airfield, and both occupants remained without injuries.
The investigation
The investigation examined the deployment sequence and the physical state of the parachute lines and canopy. The analysis focused on the mechanical behavior of the steering lines and the structural integrity of the canopy's trailing edge during the inflation phase.
Findings
- The investigation established that the malfunction was caused by the entanglement of the outermost lines from groups C and D on the left side of the canopy.
- This entanglement caused the canopy to exhibit an automatic leftward turn.
- The root cause was identified as an error during the parachute packing process.