On November 8, 2001, at approximately 1230 mountain standard time, a Cessna 140, N76975, was substantially damaged when it struck transmission lines during a low level flight near Nephi, Utah. The commercial flight instructor was not injured, but his commercial flight instructor passenger received minor injuries. Visual meteorological conditions prevailed and no flight plan was filed for this flight being conducted under Title 14 CFR Part 91. The flight originated from Falcon Field, Mesa, Arizona, at approximately 0550. According to the pilot-in-command (PIC), they were delivering the airplane from Falcon Field to Spanish Fork, Utah. They had made three fuel stops, and were on the last leg of the flight. Due to low temperatures aloft, and a "minimal cabin heater", the PIC decided to maintain an altitude of approximately 800 to 1000 feet above ground level. He was following Interstate Highway 15, and descended to a lower altitude in an attempt to read a highway road mileage sign. A few moments after leveling off, the airplane struck transmission wires. The PIC made an emergency landing on the northbound lane of Highway 15, and taxied to the shoulder to be clear of automobile traffic. The airplane sustained damage to the right side engine cowling, both wing struts, and substantial damage to the windscreen.