WPR18FA073 · Piper PA 23-250
Air America Flight Center Piper PA 23-250 · Accident: turbulence encounter en route
From McClellan Airfield (KMCC) to Salt Lake City International Airport (KSLC)
Event
- NTSB case
- WPR18FA073
- Event typeAccident: someone killed or seriously injured, or the aircraft substantially damaged (NTSB definition). Incident: an occurrence that affected or could have affected safety, short of that. Glossary
- Accident
- InvestigationHow far the investigation had got when the record was published: preliminary, ongoing, final or completed. Unknown where the source does not say. Glossary
- Completed
- API-reported fatalities
- 1 · all aircraft and ground
- Ground fatalities
- Unknown
- OperationWhat kind of flying it was, grouped by the rules it flew under: airline (US Part 121), air taxi and commuter (Part 135), general aviation (Part 91 and similar), military or government. Glossary
- General aviation
- WeatherVisual meteorological conditions (VMC): good enough to fly by looking outside. Instrument conditions (IMC): cloud or low visibility, flying by instruments. Glossary
- Unknown
Piper PA 23-250
- Aircraft type
- Piper PA-23
- Category
- Airplane
- RegistrationThe aircraft's tail number, such as N12345 or G-ABCD. Registrations are reissued, so the same one years apart can be a different aircraft. Glossary
- N54857
- Operator
- Air America Flight Center
- Onboard fatalities
- Unknown
- Route
- From McClellan Airfield (KMCC), Sacramento, CATo Salt Lake City International Airport (KSLC), Salt Lake City, UT
- Aircraft age
- About 43 years (built 1975)
- Flight rulesThe regulations the flight operated under: in the US, Part 91 (general aviation), Part 121 (airlines), Part 135 (air taxi and commuter) and others; for flights abroad, the NTSB's coarser commercial or non-commercial code. Glossary
- Part 91: General Aviation
- Phase of flightThe stage of the flight when things started to go wrong: standing, taxi, takeoff, initial climb, en route, maneuvering, approach or landing. Glossary
- En route
- Defining eventThe single coded event the NTSB judges best describes what happened (records from 2008 on). Older records name the first occurrence in the sequence instead. Glossary
- Turbulence encounter
- DamageDestroyed: beyond practical repair. Substantial: damage that affects the structure, performance or handling and normally needs major repair. Minor: less than that. Glossary
- Destroyed
Cause areas
- Aircraft › Aircraft oper/perf/capability
- Environmental issues › Conditions/weather/phenomena
- Personnel issues › Action/decision
- Personnel issues › Task performance
Approximate · Coordinates from the NTSB case API, which marks them as estimated or does not say; no uncertainty radius is established.
NTSB narrative
The commercial pilot departed on the cross-country flight in night visual meteorological conditions over mountainous terrain. About 3 hours after takeoff, the pilot reported to an air traffic controller that he was encountering clouds and was going to turn around to avoid icing conditions. The controller provided the pilot with information for the nearest airport, which was about 40 miles north. The pilot replied that it was "getting super turbulent" and that he was going to "head over" to the airport. Communication and radar contact with the airplane were lost shortly thereafter. Examination of the wreckage revealed no evidence of any preimpact mechanical malfunctions or failures that would have precluded normal operation.
Radar and GPS data revealed that the airplane was flying east when it crossed less than 900 ft above the ridgeline of a high mountain peak and turned toward the downwind (or leeward) side of the ridge, where the airplane began to descend and its speed decayed. The accident site was found near the end of the radar track on the east side and near the summit of the peak, at an elevation about 10,090 ft mean sea level. Review of weather information indicated that the accident site was located in an area favorable for mountain wave conditions with downdrafts as strong as 1,200 ft per minute, and that icing conditions were likely present at the accident site at the time of the accident. It is likely that the downdrafts exceeded the airplane's climb capability and resulted in its descent into terrain.
Although the pilot filed a visual flight rules flight plan, a search of multiple official weather briefing sources revealed that the pilot did not request an official weather briefing before the accident flight. The area of the accident site at the altitude at which the airplane was flying was included in AIRMET's for moderate icing and moderate turbulence. Additionally, winds aloft forecasts near the accident site indicated favorable wind conditions for the development of mountain wave; however, since the pilot did not obtain a weather briefing before the flight, it is likely that he was unaware of these weather conditions along his route, and the hazards that they posed to the flight.
Probable cause
The pilot's inadequate preflight weather planning, which resulted in the flight over mountainous terrain into forecast instrument meteorological conditions, icing, and mountain wave, and resulted in an uncontrolled descent and collision with terrain.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record WPR18FA073
- Event ID
- 20180112X51351
- Case number
- WPR18FA073
- Dataset
- full-current
- Source SHA-256
- 5cf380f0061817c0331a6b2d8cc7e0ee3a79bea469a1001dc5c10e56f35f5ab3
Source notes (4)
- Unreviewed is an editorial label, not an investigation status. API-sourced is not report-checked or human-reviewed. Explicit event totals are used without summing aircraft injury tables; onboard allocation is withheld. Unknown values remain unknown. The operation category is mapped from the NTSB-reported FAR part and has not been reviewed.
- Filled from the NTSB case API where the bulk record had no value: local date, investigation status, coordinates. Values present in the bulk record are kept.
- The date is the local date; the NTSB stores the UTC date 2018-01-12.
- API snapshot SHA-256: 8125718e6dffda90309739a50e2d33d9f103256cbc2e873659aae5368d6c542d; retrieved 2026-09-15T06:29:40.988Z.