The report shows that the new support arm that was fitted to Jetline in the spring of 2023 was manufactured incorrectly. It was missing a cross plate on the inside and also had serious welding defects. This led to the support arm having too little strength and breaking. The manufacturing defects were on the inside of the support arm and were not visible in the subsequent checks that were made.
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When ordering, manufacturing drawings from the original manufacturer were sent with it and an exact copy was ordered with a follow-up check of all welding joints. The supplier then outsourced the order to a subcontractor, something that Gröna Lund was unaware of.
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The Accident Commission's report shows that the subcontractor has had uncertainties about how the welding would be carried out and that these uncertainties are never discussed with their client or Gröna Lund. This led to the missing of the important cross plate on the inside. The report also shows that the original drawing has been abandoned and that there were serious welding defects on the inside. The welder who carried out the work had no formal welding training and no valid welding test certificate.