ERA15FA046 · Cessna 172 S

The student pilot had planned the instructional cross-country flight from his home base airport to another airport about 100 miles away with an intermediate stop to practice landings. However, just before departure, the flight instructor changed the destination to a different airport that was located further away and in mountainous terrain; however, he did not provide the student pilot time to plan the new flight route. No flight plan was filed nor was there any record of flight following for the accident flight. After conducting several landings at the intermediate airport, the flight proceeded toward the destination; the sun had set at this time. The instructor told the student to fly a heading of 240 degrees at 3,000 ft mean sea level (msl). The student asked the instructor about terrain elevation in the area, and the instructor responded that he was not certain of the elevations because the airplane was not equipped with a G-1000 navigation system. The student pilot reported that there were no aeronautical charts readily accessible while in flight to reference terrain elevation, and no aeronautical charts associated with the accident area were found in the accident airplane during postaccident examination. The aeronautical chart for the area showed a maximum elevation of 5,100 ft, and a mountain near the accident location with an elevation of 3,700 ft.

The instructor then began to demonstrate the autopilot to the student, including various climb rates. The student stated that the airspeed began to decline and he asked the instructor if he should add power, which the instructor did. The student reported that the engine was operating normally and responded to power inputs. However, shortly thereafter, the airplane impacted a mountain at an elevation of about 3,100 feet msl, which was about 300 feet below the mountain peak. Ground scar and wreckage information indicated that the airplane impacted the terrain in a wings-level attitude on a near horizontal flight path.

Postaccident examination of the airframe and engine revealed no evidence of any preimpact mechanical malfunctions or failures that would have precluded normal operation. Given the lack of onboard navigation charts for the area, the dark night conditions, and the instructor's decision to change the destination and not conduct preflight planning for that leg of the flight, the pilots were likely not aware of the altitude of the surrounding terrain, which resulted in controlled flight into rising terrain.

Verbatim NTSB analysis and probable cause from the NTSB dataset