History of Flight
On February 5, 2019, at about 1815 Pacific standard time, a Cessna 172M airplane, N20556, was destroyed when it impacted terrain near Desert Hot Springs, California. The pilot and passenger received fatal injuries. The flight was operated as a Title 14 Code of Federal Regulations Part 91 personal flight.
The pilot departed from Corona Municipal Airport (AJO) about 1530 and landed at San Gabriel Valley Airport (EMT), El Monte, California, about 1 hour 20 minutes later to pick up a passenger. A witness at EMT observed the accident airplane parked and tied down on the ramp adjacent to his airplane about 1710. The witness described the pilot’s preflight inspection as “rushed and cursory.” The witness noticed that the left wing tiedown line was still attached when the pilot began to start the engine, alerted the pilot, and then disconnected the tiedown by mutual agreement. The pilot then taxied to and departed from runway 19 a few minutes later.
The flight departed about 1740, and about 7 minutes later, the pilot contacted air traffic control for VFR flight-following services to North Las Vegas Airport (VGT), Las Vegas, Nevada, with a planned en route altitude of 3,500 ft. The request was granted and the pilot was provided a discrete transponder code. The pilot advised he would “follow the road” for navigation. About 16 minutes later, radar services were terminated due to coverage limitations, and the pilot was instructed to return to transponder code 1200 and re-contact ATC east of Banning Municipal Airport.
Data indicated that after takeoff, the airplane climbed to 3,500 ft and maintained that altitude until about 1814. Groundspeed varied irregularly from about 95 to 123 knots. When radar coverage resumed at the east end of the Banning Pass, groundspeed had increased to about 135 knots and remained there until about 1813. About 1814, after turning north about 9 miles north of Palm Springs airport, the airplane began a steady climb of about 600 fpm, reaching a peak altitude of 4,100 ft at 1815:03. It then began a steady descent of about 1,325 fpm until 1816:12, where it appeared to momentarily level off at 2,775 ft. Radar contact was lost about 9 seconds later. The final radar return at 1816:21 showed an altitude of about 2,800 ft, with the airplane position about 1,500 ft southeast of the impact location. Shortly thereafter, the controller advised the pilot that radar contact had been lost; the pilot did not respond despite multiple attempts. The FAA issued an alert notice at 1843, and the wreckage was located about 2120.
Personnel Information
Representatives of the operator, Flight Academy Los Angeles (FALA), from which the pilot rented the airplane, reported that the pilot had come to FALA in January 2019 to build flight time. FALA records indicated the pilot accrued 31 flight hours on FALA airplanes in January and February 2019, all in Cessna 172 airplanes, including a 1.4-hour checkout by an instructor. As a result of this checkout, FALA approved the pilot only for VFR day flights. The instructor, knowing the pilot trained in Florida, focused heavily on navigation and flying in Southern California, including discussions of potential wind issues in the Banning Pass.
Meteorological Information
A search of Aviation Flight Service Station Leidos indicated the pilot had not contacted them for weather briefings or other services. VFR conditions prevailed generally between EMT and VGT, but high winds and turbulence were predominant in existing and forecast conditions. Remote Automatic Weather Stations (RAWS) reported nearby wind information. According to a local National Weather Service meteorologist, winds at the Whitewater RAWS were gusting from 45 to 60 mph during the accident period, and the flight would have traversed Banning Pass/San Gorgonio Pass, which funnels strong winds. Data from the Burns Canyon RAWS site (10 miles north of the accident site) at the time of the accident were from the west-southwest at 35 mph gusting to 56 mph, with a maximum of 69 mph within the hour after the accident. Sunset occurred at 1720, civil twilight ended at 1746. The moon phase was a waxing crescent with 1% illumination, and the moon was just setting at the time of the accident.
Wreckage and Impact Information
The airplane came to rest on a steep unstable hillside, about 800 ft west of and about 399 ft above a road, at an elevation of about 2,500 ft, about 1,500 ft beyond the last radar return. The wreckage was highly compressed, with only a few components completely separated. The road was near the bottom of a winding valley that forms a pass through a small mountain range separating a low, flat desert from more rugged terrain. Maximum elevations of nearby peaks range up to 2,700 ft. The area is sparsely populated and illuminated. Lower cowl and navigation light lens fragments were found at the apparent impact point, about 30 ft above where the main wreckage came to rest. Ground scars were consistent with the airplane falling or sliding downhill. Relative locations of lens fragments indicated the airplane was right side up when it struck the mountain. The forward section was upright and partially covered with soil and rocks. The fuselage was severely crushed and torn; wings and empennage were severely torn and deformed. Wreckage orientation was on a heading of approximately 230°. No fire was present. First responders reported the airplane was “covered in fuel,” but the fuel had disappeared by the time investigators examined the wreckage. The all-metal fixed-pitch two-blade propeller was fracture-separated from the engine at its attach flange. All flight controls were present and attached; control cable continuity was established for ailerons, elevators, pitch trim, and rudder. The pitch trim actuator was found in a position corresponding to 5° trailing edge up. Flaps and their actuator were fully retracted. The emergency locator transmitter was fractured and separated from its mount but remained attached to its external antenna. The fuel selector valve was set to the right tank. The B-nut attached to the “VAC” port on the attitude indicator was hand tight. The attitude indicator was disassembled; its gyro rotor was offset inside the housing, free to rotate, but exhibited no rotational scoring, sometimes indicative of lack of gyro operation at the time of the accident. The engine sustained significant impact damage; propeller, magnetos, starter, alternator, and portions of the carburetor and intake/exhaust systems were fracture-separated. Magneto-to-engine timing could not be determined. The left magneto produced sparks when rotated; the right magneto was too damaged to test. Spark plug electrodes displayed normal coloration. The rear-mounted vacuum pump remained attached; three of four hold-down nuts were present and secure, one absent, with no evidence it was removed by impact. The frangible drive shaft was intact, but one vane and the rotor were fractured. The airplane was not equipped with an engine-driven fuel pump. Carburetor fracture signatures were consistent with overload; the float assembly and needle valve were destroyed. Throttle and mixture controls had been moved beyond normal operating range during the accident. Examination revealed no evidence of pre-impact anomalies that would have prevented normal operation.
Additional Information
Review of sectional aeronautical charts showed that north of the pass, terrain elevations increased significantly, generally above 3,500 ft, with Minimum Elevation Figures (MEF) ranging from 5,000 ft to 12,300 ft. The FAA publication “Pilot’s Handbook of Aeronautical Knowledge” discussed turbulence associated with ground obstructions, stating that downdrafts can be severe in valleys or canyons due to terrain effects on wind. The handbook advised prudent pilots to seek a mountain checkout before flying in mountainous terrain. A Garmin Aera 660 was recovered from the wreckage, but the most recent data file was dated December 19, 2018; no accident flight data were recovered. The investigation could not determine the pilot’s intended route or navigation references beyond “the road.” No aeronautical charts were recovered. Radar ground tracks did not overlie any published Victor Airways. The pilot communicated equipment suffix “golf” (indicating GPS equipped), but the panel-mounted GPS device did not record the accident flight, preventing conclusive determination of whether it was operating.
Probable Cause
No probable cause was stated in the source.