What happened
On January 7, 1996, a paragliding accident occurred on the frozen Savulahti bay in Riistavesi, Finland. An experienced PP2-rated pilot was attempting to conduct low-altitude training for an inexperienced student using a snowmobile as a tow vehicle. The setup utilized a 24-meter-long, 5mm polypropylene rope attached to the snowmobile via improvised hooks and a homemade release mechanism.
After several successful low-altitude maneuvers, the crew attempted a higher-altitude tow. As the aircraft ascended to approximately 5–7 meters, the tension in the tow line increased uncontrollably. The tow rope snapped near the knot, causing the paraglider, an ITV Asterope 27, to enter a violent backward oscillation. The pilot fell onto the ice, sustaining severe injuries, including a fractured heel and multiple spinal fractures from the 12th thoracic to the 3rd lumbar vertebrae.
The investigation
The investigation examined the equipment, the crew's qualifications, and the towing procedures. Investigators tested the polypropylene rope and found it failed at 1950 N, whereas a safe tow would have required only 300–400 N. The investigation also reviewed the crew's experience, noting that while the pilot was qualified for independent flight, they lacked specific instructor and towing certifications. The person acting as the tow operator (the driver) had no prior aviation or paragliding experience, and the person managing the tow connection (the hook man) was also inexperienced in aviation matters.
Findings
- The primary cause of the accident was excessive towing force that led to the sudden breakage of the tow line.
- The use of an extremely short and inelastic rope made the flight dynamics highly unstable and dangerous.
- The absence of a tension meter prevented the tow operator from monitoring and regulating the pull force.
- The crew lacked the necessary instructor qualifications and specialized training for powered towing operations.
- The improvised attachment points and release mechanisms on the snowmobile were insufficient for safe operations.