What happened
On May 3, 2018, at approximately 19:00, a group of 23 skydivers exited a SKYVAN aircraft at an altitude of approximately 4,200 meters near Piotrków Trybuński, Poland. The group was performing a formation jump. Following the completion of a "diamond" formation exercise, the skydiver in question initiated the deployment of the main parachute.
The deployment was described as a very hard opening, which caused the lines and risers to twist. This twisting led to the parachute entering a spinning state. At an altitude of approximately 700 meters, the skydiver attempted to cut away the main parachute but was unable to release the canopy. At roughly 300 meters, the reserve parachute deployed. However, both the main and reserve canopies entered a "two-canopy" (madman) configuration, descending in a spiral pattern at approximately 55 km/h. The skydiver ultimately struck a pile of wood chips at a sawmill near the airfield, which helped absorb the impact of the fall.
The investigation
The PKBWL investigation focused on the deployment sequence, the functionality of the reserve deployment system, and the physical equipment used. The investigation examined the state of the parachute harness, the RSL (Reserve Static Line) tape, and the deployment handles. Investigators also reviewed the skydiver's attempts to manipulate the release handles during the descent.
Findings
- The skydiver was using a parachute harness that was too small for his body build. This improper fit made it difficult for the skydiver to reach the main canopy release handle and the reserve deployment handle, especially as the harness tightened during the opening process.
- The primary cause of the accident was an irregular main parachute opening process, specifically the twisting of the lines and risers.
- The skydiver was unable to successfully cut away the main canopy due to the physical constraints of the undersized harness.
- The investigation found that the reserve parachute deployment was likely triggered by the skydiver's physical struggle with the harness, which caused the reserve pin to partially pull out, rather than an automatic deployment system.
- The SkyHook system, designed to accelerate reserve deployment after a cutaway, did not function because the main canopy was never released.