https://www.facebook.com/WCSART/posts/2846129165401265 As previously reported, our team Chief was involved in a rappelling accident on the night of July 4th. We felt it was important to share our conclusions of the incident. On the morning of July 5th, Chief May, Deputy Chief Hackett and Training officer Ryan completed an AAR (After action report). During the AAR, the equipment that was used, how it was rigged and photos along with first hand reports were all evaluated. We also discussed the setup and equipment that was used with outside sources for additional evaluation. Our summary follows: Chief May was rappelling on a 240’ 10mm dynamic rope using a climbing belay/rappel device. A 6mm pre-sewn Prussik cord, with 4 wraps was in place as an autoblock or conditional belay. Chief May weights 252lbs and was carrying and additional 20lbs of gear counting his pack, harness and rope equipment. During his rappel, he noted some difficulty in controlling his speed of descent and was unable to come to a complete stop. As he continued down the cliff with his feet still in contact with the cliff face, his speed was still under control although faster than you would like. At approx 90’ from the bottom, his feet were no longer able to make contact with the cliff face, his descent speed became rapid and the friction of the rope began to burn his hands. Chief May then descended through some large trees before making impact with the ground. This particular rappel device is designed to operate 10mm rope without adding the “pin” used for smaller diameter size ropes. We have concluded that with the total weight of Chief May and his equipment, along with the stretching of the dynamic rope (which decreases the overall diameter of the rope) the device did not adequately control his descent. During the initial part of the rappel, the weight of the rope hanging below him partially helped maintain control, but as he lowered further down the cliff, this effect was reduced. As a result of his speed and how quickly this all occurred, his autoblock did engage but not sufficiently to arrest his fall (Pics below show the rappel device that was used and the burn thru on the autoblock/6mm pre-sewn cord).We train to never let go of the rope and from the burns on the Chiefs hands, that never occurred. It was also noted that the autoblock never came into contact with his rappel device during his descent. In conclusion, our internal after action review has determined the system was rigged within manufacturer recommendations and backup safety measures were utilized appropriately. However the combination of this particular rappel device and the overall rappelling load may have a contributing factor. We will be evaluating how this specific rappel device will be used with the team moving forward.