Georgia, Cliff in vicinity of Camp Wahsega near Dahlonega—On 23 November, Robert D. Bridger (21), a Ranger student participating in scheduled training fell to his death. He was riding down on a suspension traverse constructed of a one inch manila, three strand rope. The rope was suspended with a total span of approximately 220 feet between two trees, one 18 inches in diameter on top of the cliff, the other 14 inches in diameter at the bottom. At the top it was secured with a round turn and two half hitches, and at the bottom with a “transport tightening knot”. The cliff was 60 feet high. The carrier for personnel riding the traverse consisted of two snaplinks on the static line, a carrier rope of 7/16 inch nylon passed through these snaplinks and down through the Swiss seat tied on the person. A belay rope of 7/16 inch nylon was tied to the center loop of the carrier rope by means of a “round turn and bowline”. The practice had been to allow the person riding the traverse to “run” down the static line to within approximately twenty feet of the pulley at the lower end of the traverse before the belayer arrested his descent.
The manila static line was very wet from a heavy rain storm the night before. The installation had been inspected by the Principal Instructor prior to its initial use and periodically during the morning which students were riding it. Twenty-two students had preceded Bridger down the traverse within two hours preceding the accident. The Principal Instructor reported that he had checked the rope not over a minute before it broke. At that time there was no evidence of fraying, bulging or excessive wear.
The fall resulting in death occurred when the one inch manila rope (static line) broke at a point approximately sixteen feet from the lower anchor and approximately ten feet from the “butterfly knot” used for the pulley in the “transport tightening knot.” It is estimated that the rope broke between one and two seconds after the man’s weight was placed on the static line. He had descended a vertical distance of approximately ten feet before the rope broke, allowing him to fall roughly fifty feet. The actual parting of the rope was witnessed by a man standing just below the breaking point and about two feet to the side. He reported that the rope just seemed to explode, fraying out in all directions immediately rather than just one strand breaking and unravelling followed by the other strands.
The exact age of the rope was not known but was estimated at about 6 months. It had been used for a variety of climbing operations during this period. When not in use it was cleaned and then stored loosely coiled in a dry building which was heated during the winter months.
Source: Newspaper clipping from F. Chamberlain. Report from U.S. Army Infantry School.
Analysis: This accident points up the inherent dangers of manila rope. It would appear that nylon rope is safer than manila not only because of its elastic characteristics but also due to its resistance to mould and mildew.