Incident Overview
A Civil Air Patrol (CAP) pilot was traveling to administer a checkride to another CAP member when the aircraft struck a cable installed by the United States Geological Survey (USGS) to monitor river flow and depth. The incident occurred in a canyon along U.S. Highway 26, near milepost 125.
Eyewitness Account
A state trooper had made a traffic stop on U.S. 26 at milepost 125. While the trooper was writing a ticket, the violator observed an airplane flying through the canyon, following a river. She informed the trooper that the airplane was below the level of the highway and treetops. Shortly thereafter, the trooper located the inverted airplane submerged in the river.
Weather and Visibility
The trooper reported no clouds in the sky and unlimited visibility at the time of the incident.
Cable Details
Investigation revealed that the aircraft had struck and severed a 7/8-inch SSC (stainless steel conduit) EEIP (Extra Extra Improved Plow) braided cable used by the USGS. The cable spanned 324 feet from support to support and had a breaking strength of 80,000 pounds. It was anchored in concrete blocks approximately 30 feet above the river's surface. Due to slack, the cable hung about 25 feet above the surface at its lowest point (midspan). Evidence indicated the airplane struck the cable at approximately the 107-foot mark. The cable broke about 6 feet from the anchor on the opposite side of the river.