Investigation Summary
The investigation revealed that the crew filed a VFR (Visual Flight Rules) flight plan for a direct route that was not authorized by the airline's FAA operations specifications. This shortcut took them through the Owens Valley, a narrow corridor flanked by 14,000-foot peaks. As they progressed south, a cold front moved into the valley, bringing low clouds, snow, and icing conditions. Because the valley lacked reliable radio navigation aids, the crew relied on dead reckoning. However, they were unaware of a 35-knot headwind that significantly reduced their ground speed. Believing they had cleared the valley's high walls, the crew turned to a southerly heading, which instead led them into a bowl-shaped canyon on Mount Whitney. The aircraft impacted a vertical cliff at 11,770 feet in a cruise attitude, indicating the pilots never saw the terrain.
Final Conclusions
The NTSB determined the probable cause was the crew's deviation from the prescribed route, which resulted in the aircraft being operated in IFR weather conditions over high mountainous terrain without adequate radio navigation aids. The lack of wing deicing boots on the DC-3 and the crew's failure to account for significant headwinds were critical contributing factors.
Photographic Evidence (1)
Video Analysis
No video analysis linked for this case file yet.
Airframe & Maintenance
Crew Experience
Captain
Fred Hall, age 43. Employed by the company since 1965.
First Officer
Raymond Hamer, age 41. Employed by the company since 1968.
Systems & Failure Modes
Propeller Anti-Icing
Isopropyl alcohol system found in the 'full open' position, confirming the crew was battling ice.
ADF Receivers
Both Automatic Direction Finder switches were found in the 'OFF' position, suggesting they were not being used for navigation at the time of impact.
Altimeters
Recovered units showed a setting of 29.78 inches, which was correct for the local conditions, ruling out altimetry error.
Interesting Facts
- 01The aircraft was not equipped with wing or empennage deicer boots, only propeller and windshield anti-icing.
- 02The wreckage was located at an elevation of 11,770 feet, while the crew had filed for an en route altitude of 11,500 feet.
- 03Propeller anti-icing flow valves were found in the full open position, indicating the crew encountered icing before impact.
- 04The search for the aircraft was extremely hazardous; at least two aircraft (a search plane and a helicopter) crashed during the operation, though no fatalities occurred in those specific incidents.
- 05The airline changed its name to Air Nevada shortly after the accident and ceased operations by 1970, though the NTSB report was published under the original Hawthorne Nevada Airlines name.
Safety Actions & Advisories
Crash Locator Beacon Advocacy
Source ↗The NTSB used this accident to strongly recommend the mandatory installation of crash locator beacons (ELTs) to prevent lengthy, costly, and dangerous search operations for missing aircraft.